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brian Rupnow
09-05-2011, 06:22 PM
I was so taken by the twin cylinder Potty Overcrank Wall Engine designed and built by Sbwhart http://www.homemodelenginemachinist.com/index.php?topic=12367.0 that I may attempt to design and build a single cylinder Overcrank engine. One or two years ago I built my version of Elmers #33 mill engine, and it turned out quite fine. http://www.homemodelenginemachinist.com/index.php?topic=7340.0 (That was the engine that powers my Pumpjack.) It was a double acting single cylinder engine, with a slide valve arrangement similar to the valve arrangement on the Overcrank engine built by sbwhart. I will probably plaegerize the design of both the aformentioned engines and add some unique design elements of my own. Although I doubt that my work will ever approach that of Elmer Verbourg or Stew's, my engines do seem to run reasonably well. I will be simplifying the design, and configuring it to work with my favourite #5-40 fasteners. The Elmers#33 engine had a 1/2" bore and 1" stroke, while the Overcrank engine by sbwhart had a 20mm dia bore and a 36mm stroke. (Roughly 3/4" dia. and 1 1/2" stroke). I don't like to work on very small parts, however I don't want to design an engine so large that the modellers with smaller capacity lathes and mills are unable to build from my plans. The design will be done in Imperial units----(I can work in metric, but I'm much more comfortable with inches.) I will design in Solidworks 3D software, but the published drawings will be saved and posted here in a .pdf format. Welcome aboard, hope you enjoy the ride.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKSINGLE--COMPLETE.jpg

brian Rupnow
09-05-2011, 06:22 PM
Thank you for the interest. I just checked my inventory of chucking reamers, and see that I have a brand new 5/8" diameter reamer. Since this is "half way" in size between the two engines which I am using as examples, I believe my engine is going to have a 5/8" bore and a 1 1/4" stroke. I like to machine my bores using a reamer, because it gets around the issue of tapered bores very nicely, and I can turn the piston diameter "to suit". This only works when I can machine my cylinder bore as a complete "thru-hole", and since the cylinder will have a bolt on endcap at both ends, this will work out very well.---Brian The following link will take you to the completed twin Overcrank engine by sbwhart.--an amazing piece of work.
http://www.homemodelenginemachinist.com/index.php?topic=14847.0
http://madmodder.net/index.php?topic=4201.msg52284#new

brian Rupnow
09-05-2011, 06:23 PM
Well, there we go---that wasn't so bad!! Basically, I took the 1/2" bore x 1" stroke cylinder from my version of Elmers 33 mill engine, and redesigned it for a 5/8" bore x 1 1/4" stroke. I am going to use the exact same steam chest and valve, so I kept the cylinder the same in the critical area where the steam chest fits up to it. Of course the raw stock for the cylinder jumped up from 1.031" square to 1 1/4" square to accomodate the larger bore. The #33 engine cylinder was 1.375" long with a 1/4" thick piston and a 1" stroke, so I pro-rated sizes to accomodate a 1 1/4" stroke with a 1/4" thick piston, which changed the overall cylinder length to 1 5/8". This is my starting point only. As this design progresses I may have to change/re-arrange things, but now I have a "baseline" to work outward from.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERSUBASSEMBLY--OVERCRANKSINGLE.jpg

brian Rupnow
09-05-2011, 06:24 PM
Thanks Stew.---After a quick check of available stock, a corporate decision has been reached to use 5/16" diameter stock for the crankshaft with 1/4" x 1/2" bar stock for the crankshaft "webs" or "throws" depending n what you call them. the crank will be built up, pinned, and loctited.
I am going to post one of Stew's video links here so I can find it for reference as I build.
http://www.youtube.com/watch?v=FBEsz7imfh8&feature=youtu.be

brian Rupnow
09-05-2011, 06:25 PM
Dang!!! I got this far this morning, and then an engineering job thats been on hold for 3 weeks was released. That means I have to stop this fun stuff for a while and do some real "money earning" work for a bit. Don't ya just hate it when you have to stop playing so you can earn some dirty old money!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERSUBASSEMBLY--OVERCRANKSINGLE-2.jpg

brian Rupnow
09-05-2011, 06:25 PM
Job is on temporary hold again. Thats okay---I have sussed out the overcrank guides and the connecting rod. It all works well and everything clears okay. if you click on the top picture you will see an animated video of it working. I just spent 20 minutes talking to my Solidworks provider figuring out how to make an animated video that lasted longer than 10 seconds.
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_CYLINDERSUBASSEMBLY--OVERCRANKSINGLE-5.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=CYLINDERSUBASSEMBLY--OVERCRANKSINGLE-5.mp4)

http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERSUBASSEMBLY--OVERCRANKSINGLE-3.jpg

brian Rupnow
09-05-2011, 06:26 PM
GENTLEMEN----We are ready to ROCK!!!! I squeezed out an hour at the end of my day to complete the model and I think it looks great!!! Tomorrow I will root through my pile of aluminum bits and see if I have a peice to start the cylinder. I will create detail drawings and post them as I progress, but my advice is that you don't copy them right yet, because this is a "prototype" and the drawings may change as I get deeper into it. I will post a download for all of the updated drawings at the end of this game, when I have this engine running.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKSINGLE--COMPLETE.jpg

brian Rupnow
09-05-2011, 06:26 PM
Well, there's nothing like beginning at the beginning!!! Here we have $92 worth of the material that will be used to build this engine.---It won't all be used----Its just that my metal supplier gets a bit oinky if I go in and buy 3" of this and 7" of that---and I don't really blame him. The majority of what you see here is in one foot lengths. The exception to that is the short peice of 5" x 1" x 6" long aluminum flatbar which was found as an "off-cut" and will be used to make my flywheel. And---a couple of peices af brass are shorter than one foot because that stuff costs like gold, and sells by the linear inch.
http://i307.photobucket.com/albums/nn294/BrianRupnow/RAWMATERIALFOROVERCRANKSINGLE.jpg

brian Rupnow
09-05-2011, 06:27 PM
FINALLY!!! I get to work on my own stuff!!!! Tomorrow morning I will start machining the cylinder. Don't bother to save these preliminary drawings, as they may change before the game is finished. I will post updated and corrected drawings when I know this one runs.---Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERFOROVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERFOROVERCRANKSINGLE--MODEL.jpg

brian Rupnow
09-05-2011, 06:28 PM
I don't usually make any sort of step by step plan when I machine somethng, as it is not usually needed. However, there are enough steps in machining a cylinder that if you get the sequence wrong you have to end up scrapping it and starting over. Last night I sat at the kitchen table and worked things through in my head and made sketches as I went along. So----this is the sequence in which I will machine the cylinder. I will have to make a drive dog to suit the 1 1/4" sq. bar, but it will be added to my arsenal of strange fixtures.
http://i307.photobucket.com/albums/nn294/BrianRupnow/LATHEDOGSANDSET-UPS-1002.jpg

brian Rupnow
09-05-2011, 06:28 PM
Those of you who are sharp of eye will have noticed that the dimensions on my hand sketch didn't agree with the detail drawing. I noticed that just in time, so no metal was cut, and I have corrected the sketch and reposted it.
The first step involved today was to cut a peice of the 1 1/4" square aluminum bar to a rough length (in this case 4"), lay out the centers in the ends of the stock, and put in a countersink in each end in my milling machine.
http://i307.photobucket.com/albums/nn294/BrianRupnow/LATHEDOGANDSET-UPS001.jpg

brian Rupnow
09-05-2011, 06:29 PM
The next step was to build a "drive dog" to transfer torque from the chuck to the part when it is held between centers in the lathe. I meant to take a picture of this drive dog before it was mounted, but forgot. I will post a picture of it later----Basically, it is two peices of angle with the toes welded together and a scrap bolt welded to one corner to engage one of the chuck jaws. Before they were welded together I milled out the radius in the inside corners of the angle so the radius wouldn't interfere with the corners of the aluminum bar. It is drilled and tapped for two 1/4" bolts that are used to "snug it up" to the aluminum part. You will also notice that I am not using a live center in the tailstock.--Why----Because my live center is so short and the lathe saddle is so wide, that I can't engage the tool with the end of the part closest to the tailstock. My "work around" for that is to machine the proper angle onto a peice of 5/8" round bar, give it a liberal dose of lithium grease, and mount it in my tailstock chuck.
http://i307.photobucket.com/albums/nn294/BrianRupnow/LATHEDOGSANDSET-UPS-1005.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/LATHEDOGSANDSET-UPS-1004.jpg

brian Rupnow
09-05-2011, 06:29 PM
Here we are at completion of the first lathe operation. No magic here---Used a conventional tool to machine the diameter closest to the tailstock. Then used a cut off tool to plunge cut on the far side of the rectangular "lump" left in the middle. I made about 5 plunge cuts side by side, enough to get my conventional cutting tool into the resulting groove, then machined up to the other square bit still captured in my "drive dog". Then put in a reverse ground tool and took a finish cut from left to right, stopping at the rectangular bit left in the middle. I make use of my home made "carriage stops" for repetitive cuts parallel to the lathe bed, and also the ones I have built and installed for the carriage cross feed.
http://i307.photobucket.com/albums/nn294/BrianRupnow/MACHINECYL-1001.jpg

brian Rupnow
09-05-2011, 06:30 PM
As promised, here is a picture of my "drive dog" by itself.
http://i307.photobucket.com/albums/nn294/BrianRupnow/drivedog002.jpg

brian Rupnow
09-05-2011, 06:30 PM
Sticking with THE PLAN---ports and other holes are drilled in milling machine.
http://i307.photobucket.com/albums/nn294/BrianRupnow/cylindermachining-2001.jpg

brian Rupnow
09-05-2011, 06:31 PM
Square lump of excess material is cut off end---
http://i307.photobucket.com/albums/nn294/BrianRupnow/cylindermachining-2002.jpg

brian Rupnow
09-05-2011, 06:32 PM
Peice is set up in lathe and center hole drilled and reamed to 3/8" diameter.
http://i307.photobucket.com/albums/nn294/BrianRupnow/cylindermachining-2004.jpg

brian Rupnow
09-05-2011, 06:32 PM
First end is "faced" in lathe.---And thats enough for one day!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/cylindermachining-2005.jpg

brian Rupnow
09-05-2011, 06:33 PM
Here is a little tip, for what its worth---as you have seen, in a previous step I drilled and reamed the cylinder to 0.375" in the chuck. The finished bore will actually be 0.625", so why did I do this? Well, because the angled steam holes that run from the ends of the cylinders up 20.22 degrees to the ports in the steamchest area actually have there "start point" almost exactly on the edge of the 5/8" bore. By leaving the bore undersized, this gives me a good solid place to start that .074" dia. drilled passage. So----why did I ream it to 0.375" then?--well that answer comes when I go to put the cylinder back in the lathe chuck.The lathe chuck is only gripping a very short area at the end of the "spare material" so that I can part the cylinder off to length in the final lathe set up, and I don't want the part to set "cocked off" at an angle in the chuck jaws. So---I chuck up a peice of 3/8" dia. cold rolled in my drill chuck and slide the cylinder over it. This ensures that the long axis of the cylinder is truly in line with he center of the chuck. Then I open the chuck jaws to accept the part and slide it into place while it is still supported on the 3/8" rod. I lock down the tailstock, then close the main chuck jaws, then unlock the tailstock from the lathe bed and slide it with the 3/8" rod back out of the way.
http://i307.photobucket.com/albums/nn294/BrianRupnow/settingupcylinchuck001.jpg

brian Rupnow
09-05-2011, 06:34 PM
We're almost down to the wire here. As you can see, a new peice of kit has been added, a digital angle meter by Wixey. I really like this one, because it has the flip up screen, that lets you view the readout panel without having to stoop way over or stand on your head to read the numbers. Both of the angled passages came out "dead on" in the correct place.
http://i307.photobucket.com/albums/nn294/BrianRupnow/finalcylmachining002.jpg

brian Rupnow
09-05-2011, 06:34 PM
This is the cylinder after it was taken back over to the lathe and drilled/reamed to its finished 0.625" bore. You can see where the ends of the angled holes end up in relationship to the finished 5/8" bore---It would have been impossible to start the drill in the correct place if the 5/8" bore had been put in first. Now for a bit of quality time on the rotary table to get the 6 tapped holes in each end.
http://i307.photobucket.com/albums/nn294/BrianRupnow/almostdonecylinder001.jpg

brian Rupnow
09-05-2011, 06:35 PM
Can't do anymore untill tomorrow. I just checked, and my 0.106" tap drill is broken and my #5-#40 and #10-24 taps are both dull and due to be replaced. Once I get this cylinder finished tomorrow, I won't be doing such "in depth" postings on every little bit that I build. Its just that cylinders are kind of a "special animal" and as such rate a bit more explanation for the new-bees out there.

vpt
09-05-2011, 06:56 PM
Very nice! I'll watch this thread!

dp
09-06-2011, 01:23 AM
Wow - all that work in under 3 minutes - that's a new record for you, Brian!

Nice looking engine.

DFMiller
09-06-2011, 01:50 AM
Brian,
Looks very interesting. I look forward to watching this grow.
It's amazing how much you can get done as Dennis says in 3 minutes.
Dave

brian Rupnow
09-06-2011, 07:34 AM
Wow - all that work in under 3 minutes - that's a new record for you, Brian!

Nice looking engine.

Nah, I'm not quite as fast as seem!!!:D :D I started this thread a week ago over on HMEM and decided to copy it over too this forum last night.

brian Rupnow
09-06-2011, 12:15 PM
This is the final step in machining of the cylinder. When I built the Elmers #33 a couple of years ago I used co-ordinate dimensions to drill the 6 holes in each end to be tapped for the bolts which hold the inner and outer cylinder heads in place. This time around I elected to set the cylinder up and drill the holes on my rotary table. I'm not sure that one method is preferable over the other, as they both seemed to work out alright. I had one "Oh $hit" while drilling the second end. I used a small c'sink to start all the holes before I drilled them, to keep the drill from wandering. On the second last hole, the HSS tip broke off the c'sink tool in the hole!!!! It wouldn't come out with any of my small picks, so I drilled completely through the cylinder from the other end and was able to tap the broken off peice out. Now I'm off to do a bunch of tapping (18 holes) and if the tapping Gods smile on me the cylinder will be finished.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLONROTARYTABLE001.jpg

brian Rupnow
09-06-2011, 12:30 PM
Tapping went okay. Now I'm off to build some ends for the cylinder.
http://i307.photobucket.com/albums/nn294/BrianRupnow/OUTBOARDCYLHEAD--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/INBOARDCYLHEAD--OVERCRANKSINGLE.jpg

brian Rupnow
09-06-2011, 03:04 PM
Yowsir,Yowsir!!!----That'll do just fine!!!-----------Actually the piston rod is just a blank peice of rod that I stuck in the hole. ;D ;D
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLWITHENDCAPS003.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLWITHENDCAPS002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLWITHENDCAPS001.jpg

brian Rupnow
09-06-2011, 04:09 PM
Time for a piston and rod----
http://i307.photobucket.com/albums/nn294/BrianRupnow/PISTON--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/PISTONROD--OVERCRANKSINGLE.jpg

383 240z
09-06-2011, 04:44 PM
Brian, I just read this whole thread, I want to say a few things to you. First off "Thank You" You have helped me so many times in several ways. You supplied me drawings for the under dash brake master. The thread you wrote on how to build a early hot rod frame was a HUGE help (on the HAMB)

The reason I am saying this is to let everybody else on here know what kind of guy Brian is. Very helpful, very knowledgeable, and eager to help. Keith

brian Rupnow
09-06-2011, 04:46 PM
Well---Aw Gee---Thanks Keith!!!!

brian Rupnow
09-06-2011, 08:07 PM
Here we have a piston and piston rod assembly----Screwed and glued----but not tatooed. And yes, it does have a quite a bit of wobble to it when the chuck rotates. The clean-up machining of the piston will fix that.
http://i307.photobucket.com/albums/nn294/BrianRupnow/piston-1001-1.jpg

Frank46
09-07-2011, 12:15 AM
Brian, your post was one that I find really interesting. Little story here, for about 25 years at the place I worked I scrounged just about all old fuel oil meter parts, screws, caps, plugs. and some different sizes of bronze boat shafting. All in a 5 gallon bucket. I had a small booklet that detailed building one of the little one cylinder steam engines. So I hop on over to my mom's place and spent the next hour trying to find it. No luck, call my brother and ask him. Good old brother just a week before took it to the junkyard and got $65 for it. Told good old brother you owe me $65 bucks. Course there were a few other well chosen words exchanged. But did get my $65. So there went my steam engine project. I used to hit every boat yard asking them for scrap pieces of boat shafting. Many times I was told that they save them for the scrapper. Darn it. Frank

Black_Moons
09-07-2011, 03:04 AM
I used to hit every boat yard asking them for scrap pieces of boat shafting. Many times I was told that they save them for the scrapper. Darn it. Frank

Consider offering them going rate + 50% for first choice of scrap?.. in cash? :)

brian Rupnow
09-07-2011, 10:08 AM
This morning I finished machining the piston to about 0.6255 (when I get into that fourth digit its more good luck and guess work than anything)---added the oil grooves, and faced both ends of the piston a bit "in place" on the rod. I had deliberately made the piston about .040" too long to leave a bit of material for this facing process. I then lapped the piston into the cylinder using some of the lifetime supply of lapping compound which I accumulated when building the Kerzel engine. I noticed that the loctite didn't Loc as much as I had expected. so I took a sharp centerpunch and dimpled the exposed end of the piston rod to keep the piston from ever unscrewing off the rod.
http://i307.photobucket.com/albums/nn294/BrianRupnow/pistonandrodassembly002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/pistonandrodassembly001.jpg

brian Rupnow
09-07-2011, 11:00 AM
Now its time to get the valve stuff out of the way---
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVEPLATE--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVEBODYCOVERPLATE--OVERCRANKSINGLE.jpg

DFMiller
09-07-2011, 11:06 AM
Brian,
On the picture of your finished piston and rod it shows a really nice fillet on the rod to piston transition. Is this a fillet of loctite?

Looking very nice.
Thanks
Dave

brian Rupnow
09-07-2011, 12:17 PM
Brian,
On the picture of your finished piston and rod it shows a really nice fillet on the rod to piston transition. Is this a fillet of loctite?

Looking very nice.
Thanks
Dave

Thats just Loctite.

brian Rupnow
09-07-2011, 01:22 PM
It may be difficult to see, but I have completed the steel valve plate that the valve slides against, and the cover plate which is made from a 1/16" clear lexan welders shield. (It is the clear cover that fits over the tinted glass on an arc welding helmet.) Of course there is a large part called the "steam chest" which is not completed yet, nor the actualslide valve itself.
http://i307.photobucket.com/albums/nn294/BrianRupnow/LEXANVALVEPLATE002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/LEXANVALVEPLATE001.jpg

brian Rupnow
09-07-2011, 02:18 PM
And now the steamchest---
http://i307.photobucket.com/albums/nn294/BrianRupnow/STEAMCHESTFOROVERCRANKSINGLE.jpg

brian Rupnow
09-07-2011, 06:31 PM
I haven't quite finished with the "steam chest" yet, but its close. The only thing standing in my way now is some finish filing on the saw cut edges. I love some of the weird and wacky set-ups I get into with this small stuff. In the picture of the peice standing on end in the vice, I am just getting ready to drill and ream the hole for the valve rod. My general procedure is to lay out the profile on the peice I am going to cut, then set it up in the mill vice, indicate off two edges, and put all the thru-holes and slots in. Then saw out most of the profile on the band saw. The only reason that I didn't cut it out completely before drilling and reaming the hole for the valve rod was that I wanted that long side of the bar to act as a "witness surface" to make sure I got it set up vertically before drilling the hole.
http://i307.photobucket.com/albums/nn294/BrianRupnow/STEAMCHEST004-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/STEAMCHEST001.jpg

brian Rupnow
09-08-2011, 08:04 AM
I have to build the valve rod now, because in its semi-completed state it will be used as a tool to finish turning the bosses on the steam chest.
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVERODFOR--OVERCRANKSINGLE.jpg

brian Rupnow
09-08-2011, 08:44 AM
Wouldn't you know it---I also have to make this part as well in order to finish machining the steam chest!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVENUT---OVERCRANKSINGLE.jpg

brian Rupnow
09-08-2011, 11:35 AM
Now this, Me darlins' is why I needed the semi completed valve rod and the semi completed nut to finish machining the steam chest! I left the nut extra long on one side, and left the valve rod extra long as well on the 3/16" diameter end. I inserted the valve rod into the steam chest, then screwed it through the nut. The .094" dia. end was setting in the .094 c'bore in the other side of the steamchest. This allowed me to set it all up in my lathe,use my long dead center in the tailstock with just a dab of lithium grease, and use my cut off tool to machine the round bosses on each side of the steam chest.---The "nut" was my drive dog to transmit torque to the steamchest and make it turn. After the diameters were turned I removed my set-up from the lathe, walked over to the belt sander and ground off the extra long boss on the steamchest (where the tailstock dead center had been). Then popped the other boss back in my lathe and used a file to turn a nice radius on that ground off boss. Now all those bits are finished.---Trust me---They are NOT BIG!!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/MACHININGVALVEBITS003.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/MACHININGVALVEBITS005.jpg

brian Rupnow
09-08-2011, 12:47 PM
A few more bits to finish off the cylinder---
http://i307.photobucket.com/albums/nn294/BrianRupnow/AIRINLETTUBE---OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVE---OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/EXHAUSTSTACK---OVERCRANKSINGLE.jpg

brian Rupnow
09-08-2011, 06:51 PM
I worked my butt off today-----and its a big butt!!!! I finished all of the peices related to the cylinder and valve. They are only little peices, but there is a lot of work in them. I have to set up the rotary table tomorrow to drill the holes in my exhaust stack. Tomorrow morning will be spent making up oiled paper gaskets for both ends of the cylinder and between all of the various valve plates. Once that is done, I should be able to shift the valve by hand and have the piston travel fully back and forth in the cylinder. If that works out all right, I will post a little video of it. There is no point in me proceeding with the rest of the build untill I know this part is going to function properly.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERFINISHED001-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERFINISHED002.jpg

brian Rupnow
09-08-2011, 06:55 PM
Ever since I started this project, I have been referring a lot to the build I did on my version of Elmers 33 mill engine. I have used the identical valve set-up, because it works so well, but have increased the cylinder size from the original 1/2" bore x 1" stroke to 5/8" bore x 1 1/4" stroke. Here is a picture of the new cylinder along with the Elmers 33 for comparison sake.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERFINISHED004.jpg

ftownroe
09-08-2011, 11:01 PM
Brian,
Absolutely incredible project. I did have one comment about the materials. You said that you only paid $92.00 for your materials, including the brass. Even with your better exchange rate, I could never find a load of materials like that for even twice that price. You have a great source of materials.

brian Rupnow
09-09-2011, 08:28 AM
Today we are building gaskets. The material I have on hand is about 0.030" thick, but as I noted on the drawings, 0.020" thick material would probably be better. These small engines are very sensitive to air loss, so you really do need these gaskets.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERHEADGASKET.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/VALVECOVERGASKET.jpg

brian Rupnow
09-09-2011, 11:32 AM
Yeahhhhhh----Success--of a sort!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_VIDEOOFVALVEOPERATION.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=VIDEOOFVALVEOPERATION.mp4)

sid pileski
09-09-2011, 12:18 PM
Brian- Nice build!
Here is a trick that I've done on numerous engine builds. I model the gaskets in CAD (ProE), SW in your case. Then put all of them that I need on an A size format (8.5 x 11) and print them on manila folder stock.
I take a regular old folder of what ever color suits your need, and cut it to 8.5 x 11 and put it in my HP printer. Hit print. Out comes a sheet of gasket out lines ready to cut and punch as needed. Soak in oil if you want before installation.

One other thing. Not to be critical. In your next engine design, I challange you to use smaller screws throughout. Sometimes the screws overpower your other fine details.

Again, nice build.

Sid

blwn31
09-09-2011, 12:52 PM
Hey Brian looks great. Not to go OT, but the guys over at CHR were asking about ya. If ya get a free minute, drop by and say HELLO.
I wish I had the time do something like that. To much to do on the boat and the hot rod is never done.

Keith

Black_Moons
09-09-2011, 01:18 PM
Nice, im amazed how much travel that little cylinder has! Shame about the valve cover plate, im sure that would of been fun to watch in action.

dockrat
09-09-2011, 01:28 PM
Brian, I really enjoy following all your builds. Just wish I had the time and patience to do the same.

AS an aside, I have the same lathe with that wide saddle and I know what its like to reach across. You should maybe pick up a MT2 to MT2 adapter so you could use your live center.

http://i253.photobucket.com/albums/hh67/Dockrat1/IMGP1331Medium.jpg

brian Rupnow
09-09-2011, 03:30 PM
Sid---Thanks for the tip about CAD generated gaskets. I've got an old package of gasket materials that I bought about 25 years ago that I am still using bits and peices from. I just lay the part to be gasketed on the gasket material and draw around it with a pencil. As far as the fasteners---I like the "big fastener" look. Really, they are #5-40 shcs. However---If anybody wants to build from the plans I post, feel free to use whatever size of fastener rings your bell. I find that using smaller fasteners results in a lot of broken taps.----Brian

brian Rupnow
09-09-2011, 03:32 PM
Dockrat---Thats a good idea. I didn't even know ther was such a thing!!!

brian Rupnow
09-10-2011, 07:19 AM
I lay in bed last night, thinking about the design of this engine. (I do this quite often at the end of the day, reviewing what I have done and what my next steps will be.) My train of thought was---What actually stops or limits the travel of the piston in the cylinder? Its not the length of the cylinder barrel,---Its the throw of the crankshaft. Because--At its maximum limits of travel, there is in theory, a 1/32" gap between the end of the piston and the cap on each end of the cylinder.----and thats not even taking into account the thickness of the gasket under each cylinder cap. Now the overcrank mechanism is connected solidly to the end of the piston rod. The cylinder is bolted in place, and the crankshaft bearing is fixed in place. If everything is not located with "dead nuts" accuracy, and the connecting rod is a fixed dimension between ends, then how does one adjust things to get that piston centered exactly in the cylinder the way it should be. I can not (Or at least don't want to) adjust the crankshaft position.---So---I must be able to adjust the position of the cylinder in relationship to the crankshaft! Sure enough, I opend Sbwharts drawing package, and that is exactly what he had done.---Put slots in the baseplate to allow him to move the cylinder closer to or farther from the crankshaft. I have any number of things which I could build next, but the danger of that now finished cylinder getting bumped off my bench onto the floor is too great. I think I will tackle the main backbone of this thing, the main spine which everything sets on, and the baseplate.

brian Rupnow
09-10-2011, 01:09 PM
A question for all the slide valve gurus out there. I am still messing about with the slide valve and cylinder that I showed in the previous video. It seems that when I shift the valve in one direction, I get lots of force to extend the piston rod. However, when I shift the valve thru its correct travel (which is only 0.100" on this engine), the retraction force of the piston rod is pretty wimpy and weak. I have tried numerous different valve positions, I have lapped the face of the valve plate and the sliding surface of the valve, and it doesn't seem to make a great deal of difference. Strong push on extend, weak retract. This puzzled me to such an extent that I switched my new valve gear with the valve gear on the Elmers 33 that I built two years ago (its the exact same) and the Elmers 33 runs fine with my new valve gear on it. I then put the complete valve set up from elmers engine on my new cylinder, and it still acts the same. Strong extend, weak retract. Common sense and science tells me that the force should be the same in both directions, but it isn't!!! Can anybody offer a reason for what I am seeing?---Brian

brian Rupnow
09-10-2011, 02:14 PM
Yes, I have tried all the suggested tricks. I know that the area of the rod must be subtracted when doing force calculations on the return stroke, but in this case the rod is too small to account for such a large difference. I have done the soapy water test, the gunk in the passage test, all the tests which make sense. I have spent a day screwing about with this, but have decided to forge onward and sort it out at a later date if necessary. Tests show the same effect on my Elmers#33 and it runs fine, so I'm not going to worry about it right now.---Damn the torpedoes!!! On to the next part!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERRISER--OVERCRANKSINGLE-1.jpg

dp
09-10-2011, 04:58 PM
Can anybody offer a reason for what I am seeing?---Brian

Asymmetry in the way the piston seals in the bore, perhaps, or the valve timing is asymmetric?

brian Rupnow
09-10-2011, 05:14 PM
And this is how I spent my afternoon!!! Whatever is happening with the valving will get sorted out "eventually". Really, it is losing very very little pressure where the piston rod passes thru the cylinder end cap. Right now, its "On with the build".
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERRISERINPROCESS001.jpg

brian Rupnow
09-11-2011, 07:58 AM
GOOD NEWS THIS MORNING!!!! I came down to my shop, took both end caps of the cylinder, and hooked the airline to my valve. I cycled the valve in both directions, and air flowed out, full blast at each appropriate end when the valve was shifted. ???? I then reversed the caps on the cylinder, and when the valve shifted, the piston rod went roaring in and out like gangbusters.???? What the heck------So, I reversed the end caps again, back to where they should have been and it still worked great!!!! Must have been a peice of "spooge" (I think thats Marv's word, I like it) in the air passage drilled thru the cylinder to the rod end and it blew out when I had both end caps off. I feel much better about the world now!!!----Brian

brian Rupnow
09-11-2011, 12:49 PM
So here we have a "Cylinder Riser". Other than a bit of cosmetic work and some hole tapping its finished. I am very pleased with it, and I have come up with "Rupnows Theorum"---Namely, that "The more work you have invested in a single part, The more terrified you become that you are going to do something irrevocable and screw it up"!!! It has turned out fine, and its just to darn nice outside for me to spend anymore time in the machine shop today.---Thanks for looking.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERRISERFINISHED003.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERRISERFINISHED002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERRISERFINISHED001.jpg

brian Rupnow
09-11-2011, 02:00 PM
Time for some miscellaneous bits---
http://i307.photobucket.com/albums/nn294/BrianRupnow/BEARINGSUPPORT--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKGUIDES---OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/PIN-1OVERCRANKSINGLE.jpg

brian Rupnow
09-11-2011, 02:02 PM
And a few more---
http://i307.photobucket.com/albums/nn294/BrianRupnow/PIN-3OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CONRODSPACER.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/PIN-2OVERCRANKSINGLE.jpg

brian Rupnow
09-11-2011, 03:46 PM
And more yet---
http://i307.photobucket.com/albums/nn294/BrianRupnow/CONNECTINGROD-3.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CONNECTINGRODCAP-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/BASE--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CON-RODLINK--OVERCRANKSINGLE.jpg

brian Rupnow
09-11-2011, 08:15 PM
Well guys, so far everything I've built is according to drawing. I have noticed, as I build from the prints that I have posted, that there are a few missing dimensions, and I have added them but not reposted to Photobucket. The drawings will all be saved as .pdf files when the engine is completed, and I will post a download link for anybody that wants them. So far I am liking the proportions of this engine, but thats the "magic" of 3D cad, in that it lets me get a good feel for sizing before I cut any metal. I was quite concerned about the weakness in the "retract" stroke of the cylinder, but fortunately that is sorted out now. It just makes me absolutely crazy when something doesn't work right, that logic tells me should work perfectly and I can't find any mistake in how I have machined the part!!!!! I will start tomorrow to make the parts that I have just posted drawings of, and will keep you updated with pictures as things progress. Thanks for looking.----Brian

brian Rupnow
09-12-2011, 10:39 AM
This mornings offerings to the Machining Gods is a nice pair of bearing stands. Now, a little story about these---Firstly, much to my chagrin, I discovered that my metal supplier doesn't stock any 5/16" aluminum flatbar.---Only 3/8". This means that I either machine these down to 5/16" thick, or decide on a minor "work around" to use them as they are. The one on the flywheel side of the engine doesn't matter. The one on the other side though---well, we'll see. Fortunately I haven't yet built the main baseplate, so I can probably make it work.---Secondly, you will notice a pair of 1/8" holes just inboard of the two bolts holding the bearing plates in place, that weren't on the drawing. They have now been added to the drawing,and here is why.-- I like to Loctite the bushings in place, and bore them to final size "in assembly'. This works great untill the first time you have to remove one or both bearing plates, and then you can NEVER get them back into proper alignment without a bind on the crankshaft. So---once everything is set up and the bushings bored in place, I will use the bearing plates as guides to drill 1/8" holes in the side of the "cylinder riser" for dowel pins. That way no matter how many times things have to come apart, the bushings stay lined up perfectly. And thirdly---the oil holes are not in the bearing plates yet. That is because I add them after the bushings are loctited in place. The small 0.074" dia. hole goes thru the bearing housing AND the side of the bushing. The larger oil reservoir hole is added in the same set-up, for the sake of concentricity.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/BEARINGSTANDS002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/BEARINGSTANDS001.jpg

brian Rupnow
09-12-2011, 02:28 PM
Everybody likes a nice baseplate----BUT---NOW I HAVE TO WARN YOU---I have changed and reposted the base and the bearing support drawings, as of right now!!! This was necessitated by the fact that I chose to keep the bearing supports as 3/8" plate, and consequently the holes in the baseplate shifted by 1/16". Again,I will be posting updated drawings at the end of this build, however where a drawing already posted has dimensional changes I am reposting them as I go along here, rather than have incorrect drawings posted.
http://i307.photobucket.com/albums/nn294/BrianRupnow/BASEPLATEFINISHED002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/BASEPLATEFINISHED001.jpg

brian Rupnow
09-12-2011, 05:08 PM
And to end the day off in style---We have a pair of "Overcrank Guides". I have no idea what the proper name for some of this stuff is, so I'm making it up as I go along. Damn, this is a lot of work---I could never have done this (machining) for a living!!! I am rapidly closing in on the "exciting" part of this build----The Overcrank mechanism itself. I imagine it will be quite a "task" to get everything lined up so that it slides and doesn't bind the cylinder. I have absolutely no engineering design work at the moment, so I am able to really spend the entire day working on this project. Fortunately, I did get paid today for a small job I did three weeks ago, so good wife promptly went up and bought a bottle of red wine and a bottle of white (His and Hers) ----and I'm headed upstairs ro make some inroads on it as soon as I finish posting this!!! I hope you are enjoying the build. Talk to me people----Its lonely here when I don't hear from you.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKGUIDES002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKGUIDES001.jpg

brian Rupnow
09-13-2011, 04:04 PM
Today was major thrash time in my little machine shop. There are only---count them---five new parts, but its 4:00 PM now and I started at 7:30 this morning!!!! The overcrank mechanism machined up exactly according to drawing, and with only minor tweaking went together real well. I was quite excited about getting these parts done, as they truly are "Something new". Right now, as it sets, the flat head capscrews are setting about .008 proud of the slide bars, and I have to decide wheter to deepen the countersunk holes or cheat a little bit and grind .010" off the top of the flat head capscrews.---At any rate, its together----TA-DA!!!!!! I guess its almost time to start thinking about a crankshaft and con rod.
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKMECHANISMASSEMBLED002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKMECHANISMASSEMBLED001.jpg

brian Rupnow
09-13-2011, 08:47 PM
I guess since I plan on building this tomorrow, a drawing would be in order. WARNING WARNING--I got thinking about this last night and decided that I needed two raised bosses to keep the con rod from floating around, so the drawing has been modified.
http://i307.photobucket.com/albums/nn294/BrianRupnow/SUBASSEMBLYOFCRANKSHAFT--OVERCRANKSINGLE.jpg

brian Rupnow
09-14-2011, 08:56 AM
I just did some detective work with my suppliers and came up with the following.---I can buy a #5-0 tapered reamer which has a 1 3/16" flute length, is 0.0966" dia on the big end and and 0.0719 on the small end. It takes a #5-0 tapered pin, which another supplier is trying to source for me. Nobody knows what drill size you use first, before the tapered reamer. The size range sounds about right for use with a 5/16" diameter crankshaft, but I am totally in the dark on this subject, having never used a tapered pin in my life.----Can anyone shed some light on this for me please.----Brian

brian Rupnow
09-14-2011, 11:50 AM
I'll make bushings while I wait for tapered pin information.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CRANKSHAFTBUSHING---OVERCRANKSINGLE.jpg

dp
09-14-2011, 02:19 PM
Nobody knows what drill size you use first, before the tapered reamer. The size range sounds about right for use with a 5/16" diameter crankshaft, but I am totally in the dark on this subject, having never used a tapered pin in my life.----Can anyone shed some light on this for me please.----Brian

If you draw your taper it should be fairly simple to add 3 or more different drill sizes to the drawing to indicate how to step-drill the bore before tapering begins. If the metal is not particularly difficult to work then you need only drill slightly smaller than the final diameter of the small end of the tapered bore. The beauty of tapers is that it is difficult to screw it up - you just grind the pin to length and ignore the perfect bore dimensions. Repeat as needed. Just try not to mix exchangeable parts that have been tapered as no two tapers will match for plunge and alignment on all axes.

Toolguy
09-14-2011, 04:07 PM
I've done lots of tapered pin holes. Just use a drill size that the end of the reamer will fit into. Run the reamer in till it comes out the other side a little, run it slow with cutting oil pretty much like any other reamer. If you set a depth stop and do all holes to the stop, the finished pins will be fairly exchangeable, though the other parts must remain matched as they were originally drilled as mentioned above. Check the first hole with a pin for depth inserting by hand, remembering that it will go deeper when seated with a hammer.

brian Rupnow
09-14-2011, 04:17 PM
The bushings are finished and installed. Since I want to continue the momentum of this build, and not wait for a week to get in tapered pins, I will just go back to my original plan and use 3/32 dia. cold rolled rod for my pins instead of the split dowel pins. If it all flys apart at some point in the future, I will remake it with tapered pins then. At the speed and power this engine will develop, I doubt that any buildings will be destroyed or lives lost if the crankshaft does "Come a cropper!!!"

brian Rupnow
09-14-2011, 07:02 PM
Here is a "How I did it" shot---Turning the boss on the crankshaft "throw" (also called the web". I have drilled and reamed the 3/32" holes which will eventually pin the throw to the crankshaft, and also a "throw away" peice of 5/16" rod about 1 1/2" long. The long peice of 3/32 dia. rod has a dab of Loctite on it to hold it from falling out, and the 5/16" rod is gripped in the 3 jaw chuck. I know there are other ways to do this, but this method seems to be working well---so far. Tomorrow morning I will heat it up a bit, remove both the 3/32 rod and the 5/16" rod, machine the other "throw" the same way, and then be ready to set them up on the final 5/16" peices of rod that form the actual crankshaft, then cross drill, pin, and Loctite.
http://i307.photobucket.com/albums/nn294/BrianRupnow/BOSSONCRANKWEB002.jpg

brian Rupnow
09-15-2011, 08:46 AM
I guess its time for some valvey type drawings--
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENDFORVALVEROD--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/SUBASSYOFVALVEROD--OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENDFORVALVEROD-2-OVERCRANKSINGLE.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/ECCENTRIC--OVERCRANKSINGLE.jpg

brian Rupnow
09-15-2011, 03:44 PM
In case I never mentioned it---I HATE 4 JAW CHUCKS WORSE THAN SNAKES!!! I hate them worse than Canadian Winters!!!---And Damn, I really hate them when I make a cam thats supposed to have an 0.050" offset and somehow ends up with a .025" offset!!!

brian Rupnow
09-15-2011, 05:12 PM
Not much to show for a hard days work!! A cam, the big end for the valve rod, and a rather be-snotted looking crankshaft. Why does the cam have a set-screw in both sides?---Because the end broke off the miserable 1/8" dia. c'sink, tool I had and I couldn't get it out---so I had to drill thru from the other side and push it out. This left me with an extra hole that I didn't want, so I just threaded both of them. One set screw will get a dab of Loctite and just be a "dummy" while the other does the actual holding work. I totally messed up my first attempt at the cam, but other than hurt feelings I survived it. That nasty crankshaft will get all cleaned up tomorrow and the extra bits cut off. In my heart of hearts, I only want to install that crankshaft once, so I wanted to finish all the bits that fit on or over the crankshaft today.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CAMANDCRANKSHAFT001.jpg

Duffy
09-15-2011, 06:45 PM
Brian:-Two points. First, you only have to step-drill for the larger/longer taper pins, such as #4 and up. Second, I note that you use locktite for crank throws and wonder why not silver solder? I know that it taks a bit of practice, but once you get the hang of it, it sure makes life simpler. Hell, if I can do it ANYONE can!
An unrelated point. If you REALLY hate 4-jaw chucks, there is a "magic formula" for calculating shim thickness for one of the three jaws to get a desired offset when turning eccentrics. The system really does work; it was posted in a Model Engineer issue many years ago. if you FORCE me, I will try and find it. Duffy

brian Rupnow
09-15-2011, 07:25 PM
Brian:-Two points. First, you only have to step-drill for the larger/longer taper pins, such as #4 and up. Second, I note that you use locktite for crank throws and wonder why not silver solder? I know that it taks a bit of practice, but once you get the hang of it, it sure makes life simpler. Hell, if I can do it ANYONE can!
An unrelated point. If you REALLY hate 4-jaw chucks, there is a "magic formula" for calculating shim thickness for one of the three jaws to get a desired offset when turning eccentrics. The system really does work; it was posted in a Model Engineer issue many years ago. if you FORCE me, I will try and find it. Duffy
Duffy--I can and do silver solder a lot of my stuff. The problem with silver soldering on a crankshaft, is that the damn stuff runs everywhere and then has to be machined off. I was just attempting to avoid the clean up issue by using Loctite and pins. I know there are formulas out there for making eccentrics in 3 jaw chucks. I do hate 4 jaw chucks, but its very rare that I have to use them, and it is really something I have to learn to use better. I was being somewhat facetious when I said that I hate them worse than snakes---but not too facetious.:D :D

brian Rupnow
09-16-2011, 02:34 PM
Well, Darn---That turned out nice!!! The crankshaft cleaned up beautifully, and seems very solid. The con rod is exactly per drawing, other than the fact that I bought a 3/16" ball nosed milling cutter this morning while I was out, and put a cosmetic groove down each side of the con rod.----I've never done that before. Can you believe that I only have two parts left to make!--A very small simple spacer for the end of the con-rod where it attaches to the overcrank mechanisn, and the flywheel. I am going to make a drawing of the flywheel as a one peice, turned from steel or brass. The reality however, is that I still have a big chunk of 3.5" o.d. heavy wall bronze tube left over from my kerzel build, so I will build a two part flywheel with an aluminum center, same as I did on the Kerzel.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CON-RODANDCRANK002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CON-RODANDCRANK001.jpg

brian Rupnow
09-16-2011, 03:57 PM
I think this is the last detail drawing.
http://i307.photobucket.com/albums/nn294/BrianRupnow/FLYWHEEL--OVERCRANKSINGLE.jpg

brian Rupnow
09-16-2011, 06:51 PM
Thanks guys. I just turned a peice of aluminum to the correct size and Loctited it into the bronze ring that I cut off the heavy wall bronze tube. Its time for me to buy a new pair of digital Vernier calipers. My micrometer only goes up to 1", and when I turned the aluminum to what was supposed to be a "light press fit" according to my current digital calipers it ended up being a "falling in fit". Damn!!! Issue was resolved by going around the perimeter of the aluminum blank and giving it numerous good 'whacks" with a center punch and hammer. This raised the material enough to get a good interferance fit, and so , liberally coated with Loctite 638 it will be ready to finish machine in the morning. Its going to be a heavy little bugger, but my gut tells me that with the added drag from the overcrank mechanism it will need to be.
http://i307.photobucket.com/albums/nn294/BrianRupnow/FLYWHEEL-1002.jpg

dp
09-16-2011, 09:47 PM
Brian - the fit and finish on this project is the best of your projects, and all those were pretty darn good.

brian Rupnow
09-17-2011, 07:35 AM
Brian - the fit and finish on this project is the best of your projects, and all those were pretty darn good.
Thanks Dp----Practice makes---better:rolleyes: :rolleyes:

brian Rupnow
09-17-2011, 10:34 AM
So---This is it!!! All the parts are finished. Now if I can only get it all together.---Jeez---I hope this thing runs!!!
http://i307.photobucket.com/albums/nn294/BrianRupnow/FLYWHEELFINISHED001-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/FLYWHEELFINISHED002-1.jpg

Toolguy
09-17-2011, 02:06 PM
Great looking project Brian! :) I'm sure you'll have it spinning away in no time!;)

brian Rupnow
09-17-2011, 06:29 PM
Well kids----There it is assembled. All the parts fit. As expected, I have numerous binds and hard spots, but I will chase them down tomorrow. I'm just very happy that it went together so nicely.
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENGINEASSEMBLED002-1.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENGINEASSEMBLED004.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENGINEASSEMBLED003.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/ENGINEASSEMBLED001.jpg

rode2rouen
09-17-2011, 07:44 PM
Very nice work, Brian!!
Out of curiosity, what drawing package do you use?


Rex

brian Rupnow
09-17-2011, 07:48 PM
Very nice work, Brian!!
Out of curiosity, what drawing package do you use?


Rex
Solidworks. Started with it 10 years ago, after 33 years on a drafting board and two years of Autocad.

Black Forest
09-18-2011, 03:41 AM
Great job Brian!

Tel
09-18-2011, 05:12 AM
"-It would have been impossible to start the drill in the correct place if the 5/8" bore had been put in first. "

:D Nothing is impossible mate. I always take my bores straight out to finished size and then cut a little ledge with an end mill to start the drill for the passage(s). Way back when, we used to file a little flat on the rim of the bore and centre pop that.


http://inlinethumb21.webshots.com/49492/2421803950105506259S500x500Q85.jpg (http://news.webshots.com/photo/2421803950105506259Ytmxwp)

brian Rupnow
09-18-2011, 12:26 PM
. Here we are in "Run-in" mode. 10 minutes at mid range rpm with the bolts all just snug, everything drenched in oil. Then 15 minutes with all bolts snugged up "fairly tight"---Then 20 minutes with all bolts torqued down to finished torque. Then it should be very free to turn over.
http://i307.photobucket.com/albums/nn294/BrianRupnow/RUNIN001-1.jpg

Al Messer
09-18-2011, 01:59 PM
HEY, TEL!! Please post a thread on that 3 cylinder radial in the picture------PLEASE!!

Al

j king
09-18-2011, 03:05 PM
looks great Brain..

Tel
09-18-2011, 04:34 PM
HEY, TEL!! Please post a thread on that 3 cylinder radial in the picture------PLEASE!!

Al

Gee Al, it's so long ago I'm not sure if I can remember exactly what I did! I'll see what I can dig out for you ol' buddy!

brian Rupnow
09-18-2011, 08:28 PM
Now I'm at the difficult time. The engine overcrank mechanism works beautifully, and is totally free, to the point where a flip of the flywheel carries it through two or three revolutions. I am again fighting issues with my slide valve. The cylinder extends quite marvelously under air pressure, but doesn't want to retract when I shift the valve. The last time this happened, I took the cylinder end caps off and shifted the valve, resulting in a blast of air out of the cylinder passages and clearing a peice of what Marv so aptly called "Splooge"---and that fixed things. I can only hope that repeating this will clear anything remaining and fix it again. When I first assembled the cylinder, I didn't want to use a cardboard gasket between the slide plate and the aluminum cylinder, so I resorted to using some liquid silicone from a tube. This has now came back to bite me on the butt. The silicone extruded into the air passages when I tightened the four bolts holding the steam chest in place, and I think (hope) thats what is causing my issues with the piston not retracting properly. I won't be posting anything more on this build untill I have a video of the engine running. I can just tell from the action of the mechanism that its going to be a beautifull thing under power.

Al Messer
09-18-2011, 10:02 PM
Gee Al, it's so long ago I'm not sure if I can remember exactly what I did! I'll see what I can dig out for you ol' buddy!


Many thanks, TEL I'm sure that it will be of interest to us all.

Al

brian Rupnow
09-20-2011, 09:19 AM
I FOUND IT!!!! At least I'm pretty sure I found it. I pulled the cylinder apart this morning for "Investigation and analysis". Remember when I drilled the bolt pattern in the ends of the cylinder way back at the very beginning, and the end broke off my c'sink so that I had to drill that one hole completely thru from the far end of the cylinder to pop the tip of the broken c'sink out and tap the hole at that end. Well that long hole intersected with one of the four tapped holes which hold the steam chest in place, and break thru into the cylinder body. This acted as an air bleed internally in the cylinder body. I just epoxied a peice of .093" diameter steel rod and plugged that hole in the center with it, leaving the thread at both ends for the bolts that hold the end caps on. Cross your fingers.---This may have it!!!

JCHannum
09-20-2011, 12:15 PM
Many thanks, TEL I'm sure that it will be of interest to us all.

Al
Not to hijack Brian's thread any further, but perhaps it is the Westbury Cygnet engine?

http://www.hemingwaykits.com/acatalog/The_Cygnet_Royal___Edgar_T_Westbury.html#aCygnet

brian Rupnow
09-20-2011, 01:19 PM
Some how, in some way, I have angered the machining Gods. Having tried everything else, and not having success, I just went down to my metal supplier and bought a foot of seamless steel mechanical hydraulic tubing. I am going to hog the cylinder bore out to 11/16" diameter and Loctite in a liner, then ream the liner in place. Yes Marv, you are right. Elmers plans didn't call for any tapped holes breaking into the cylinder bore. I did that on the Elmers 33 that I built because I couldn't figure out how else to tap such short blind holes.---And I got away with it. My bad---I'm learning as I go along here. I didn't get away with it this time. The holes which break thru into the cylinder bore are leaking air from end to end. I consider myself duly chastised and won't make that mistake again. Sometimes I wish I was smart instead of good looking!!! Stay tuned.----Brian

brian Rupnow
09-20-2011, 03:47 PM
So this is my save for today. The steel tube I bought was .750" o.d. x 0.610" i.d. I turned the o.d. to .688" and while in the same set-up in the lathe I took a skim cut off the i.d. with a boring tool, then finish reamed it with lots of oil and a .625" reamer. My initial thought was to ream it in place after it was installed in the cylinder, but decised for the sake of concentricity to turn the o.d. and the i.d. in one set up. I cut the tube to length 3/32" shorter than the length of the cylinder, to allow for the intrusion of the ends on the inside of the cylinder caps. I also filed a v-groove in both ends to line up with the holes in the cylinder that let the compressed air into either end. I set the cylinder up in my milling machine and bored it out to .689"
http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=CYLINDERLINER002.jpg
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERLINER001.jpg

brian Rupnow
09-20-2011, 03:51 PM
And here we are with the cylinder liner Loctited in place with #638 Loctite. I washed both parts with methyl alcohol before installing the liner to wash away all traces of oil and grease first. Tomorrow I will hone the i.d. of the liner with my brake cylinder hone to give it a somewhat smoother finish than the reamer leaves.--And yes, I did clean that loctite out of the tapped hole.
http://i307.photobucket.com/albums/nn294/BrianRupnow/CYLINDERLINER003.jpg

brian Rupnow
09-21-2011, 10:40 AM
Old age and treachery triumph once again!!! I got up early this morning, machined a new closer fitting piston from brass and lapped it into the cylinder with #400 and then #600 lapping compound. That extra flywheel on there was not necessary, it was still on from yesterday, but the engine is now setting here on the corner of my desk chugging away without the extra flywheel. The only change necessary to the drawing of the cylinder is that the tapped holes must not break thru into the cylinder bore. Or else do like I did and install a liner after the fact. The slide valve is obviously working just fine. In the video, the engine is running on 40 psi, but I expect that after it runs for a while it will run on less. after I let it run for a couple of hours I will clean it up and post a better video.----Brian
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_OVERCRANKSINGLEFIRSTRUN.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=OVERCRANKSINGLEFIRSTRUN.mp4)

brian Rupnow
09-21-2011, 02:33 PM
Here is the official 'Cleaned up' video.
http://i307.photobucket.com/albums/nn294/BrianRupnow/th_OVERCRANKSINGLECYLINDERENGINE.jpg (http://s307.photobucket.com/albums/nn294/BrianRupnow/?action=view&current=OVERCRANKSINGLECYLINDERENGINE.mp4)

Toolguy
09-21-2011, 03:00 PM
HA! I knew that would happen. You did get it running!:D It turned out very nice Brian! Thanks for sharing the build with us! :)

brian Rupnow
09-21-2011, 03:15 PM
And a drawing to tie all the parts together---
http://i307.photobucket.com/albums/nn294/BrianRupnow/OVERCRANKSINGLEASSEMBLYDRG.jpg

brian Rupnow
09-21-2011, 03:48 PM
Here is one more drawing I forgot.
http://i307.photobucket.com/albums/nn294/BrianRupnow/ECCENTRICSTRAPRETAINER.jpg

brian Rupnow
09-21-2011, 04:06 PM
Now, if I have remembered how to do this correctly, clicking on the link will get you a download of all the drawings in .pdf format from MediaFire. They will be in a .zip file. Click on the "start download" link and select "save" and it will ask you where you want to save it to. After you have saved it to somewhere on your computer, double clicking the file should open it and make all the drawings accessable. If anybody sees any glaring errors or omissions, please let me know.
http://www.mediafire.com/?s1wx05r8347s2y3