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redchief344
05-15-2006, 09:30 PM
I have a question concerning the drawing for the Finger Engine in the May/June HSM. Item 7 shows Lever length, thickness, hole placement and end width dimensions ...but... I cannot figure out what the major width dimension would be at it's widest point with the given information (i.e. 1/2" on one end and 3/8" on the other).

Am I not seeing this measurement, or is it assumed that you make it any width you chose, as long as it clears the base?

Thanks,

Bill

PTSideshow
05-15-2006, 11:01 PM
Your not missing anything there isn't a measurement given for the widest part in the other set of drawings for the same engine that was i n the NAMES program as the project for 2005 no measurement but if I remember it's an 1" wide at the center of the pivot screw.:D The only real crital distance of the project is the connecting rod end to base so it clears as the engine gets to spinning.

JCHannum
05-15-2006, 11:06 PM
I don't see any dimension either. The drawing is about 1/2 size, and measuring it gives about 7/16", so 7/8" or 3/4" will work OK.

The dimensions ae not critical as long as the hole spacing is per drawing and everything clears it will work.

IOWOLF
05-16-2006, 05:01 AM
3/4" it's simple to figure out,But as said it is not a critical dimention.

redchief344
05-20-2006, 10:16 AM
Glen, Jim and IOWOLF...thanks for your input.

Bill

ShawnR
06-23-2006, 09:06 AM
Hello

I just joined. I have a metal lathe but just learning how to use it. I got it mostly to supplement my other shop activities but find it fun to use. I found the article on the Finger Engine and subsequently, through trying to find ""several NAMES vendors",as quoted in the article, found this forum. I had no luck finding vendors of the flywheel.

Does anyone know whos sells that flywheel?

Thanks

Shawn

JCHannum
06-23-2006, 10:04 AM
Shawn;

Try Myers Model Engine Works at myersmodels@aol.com

Or Martin Model & Pattern at www.martinmodel.com

You will have to order by the OD of the flywheel. They both have cast, spoked flywheels for sale.

Clarence Myers is at the Thresher's reunion in Wauseon OH, this weekend, and you might not connect with him this weekend. I'm headed there now.

I edited to correct Clarence Myers contact information, it is an e-mail address.

Tin Falcon
06-23-2006, 08:16 PM
Shawn:
Pm Research sells flywheel casting there web site is http://www.pmresearchinc.com/store/customer/home.php
I think you will find several options in aluminum or bronze/brass
you may also want to browse the site for other neat things. They sell steam engine casting kits as well as casting kits for model machiery. They exhibt at cabin fever. I have met and talked with these folks as well as purchased there product. Normal disclaimers just a happy customer.
Tin Falcon

smagovic
06-25-2006, 08:51 PM
Guys, I believe the URL for Myers is actually: www.myersengines.com/ . Take care. Vic Smagovic

smagovic
06-25-2006, 08:52 PM
sorry duplicate again

Sprocket
07-09-2006, 09:39 PM
I needed a break from the project I was working on, and this seemed like the right one. It is a simple enough project that my wife wants to build one, but quite satisfying and fun to play with. As with any project, I had to embellish a little.

http://img.photobucket.com/albums/0903/Sprocket/DSCN0346.jpg
http://img.photobucket.com/albums/0903/Sprocket/3f8db215.jpg

IOWOLF
07-09-2006, 10:01 PM
Nice,very nice.

Millman
07-09-2006, 10:06 PM
Hey now; what do you mean with{SUCH} finishes like that???? Tryin' to make Evan work harder? Fine work!

Millman
07-09-2006, 10:07 PM
I take that back; noticed some tooling marks!

ShawnR
01-09-2007, 09:28 AM
Wow, after I posted the request, a butterfly flew in the shop and I never got back to the Engine. I actually started my engine recently and hope to submit a photo but it sure will not look as nice as Sprockets. It is my first serious (for me :o ) lathe project. Rounding up the 1/2" aluminum was my stumbling block but I was in the steel yard a couple months ago and found some so I guess that was the catalyst needed.

I have not ordered a flywheel but thought I would try one from mild steel. That lead to making a circle cutter for the torch... :cool:

I did not put lightening holes in mine and the outside is not the suggested 1/2"...it is 3/8"...the web is 1/8" with a hub about 1 " and the OD is 3 1/2". the shaft is standard so I can replace it with a cast iron wheel in the future.

If this works (even meagerly OK), I will likely make some more for gifts and lathe,layout,milling practice. I will check out the links more thoroughly then.

Thanks for the responses and sorry for not jumping on it. I did not have the auto notification set up but do now.

Cheers,

Shawn

DeereGuy
01-09-2007, 09:45 AM
This looks like something fun to build and set at my desk at work.

mlucek
01-09-2007, 05:04 PM
I just ordered a few flywheels from PM Research's web site .... in preparation to build 1 or more of these cute little thangs :D

ShawnR
01-25-2007, 12:24 AM
Well, finished it up. As expected, it is not nearly as nice as Sprockets, but considering my experience, it spins so I am happy.

http://i150.photobucket.com/albums/s82/Shawnr_bucket/fineng.jpg

The timing is very critical though. Is it the nature of the beast or is it that my flywheel is too heavy in the middle, ie no lightening holes? I was not sure how to make those, with the tools I have and still have the flywheel balanced. I will probably order a wheel from PM as previously suggested. It should slip in as a replacement now that the rest is done.

Does anyone have any good links to articles on laying out projects? This one was pretty simple and it showed me how little I know about laying out, ie measuring in decimals. (I come from the woodworking hobby) I realized that the dimensions were factors of 16ths so that helped but if I had to measure in from an edge say some other number ie .523, how does one do that?

Sprocket
01-25-2007, 06:24 PM
ShawnR -

It's not just you, it's the nature of the beast. Finger timing is critical, it may help to both push and pull on your pedal to smooth things out. I think the overall weight of the flywheel may mean more than the holes.

Measuring things like .523", I would use the table feed to measure. Wiggle up the edge, with the play taken out (your moving the right direction already) then use the dial to measure your distance. Sometimes you can make those measurements with a dial caliper, but moving the table is usually pretty easy.

Good job. Things get easier every time.

Doug

ShawnR
01-25-2007, 11:20 PM
Hi Doug

Thanks for the reply. I was wondering about connecting link lengths and things like that. My wife was considering using it in the classroom for a lesson on motion and I was trying to relate it to levers, pulleys, etc. things she has taught already. It was frustrating to try to get it to run smooth enough to demonstrate motion, but on the other hand, good to demonstrate the importance of timing. Fun anyways.

As for the measuring, I do not have a mill so no table to move. ie, In woodworking, if I had to make two holes, the first 1.5" from an edge (or anywhere on a surface) and the second 2.25" from that, I could measure in the distance to the first hole, then measure in the distance to the second hole, (3.75"). Since machining involves so much accuracy and rulers (that I use) don't go to thous, how does one do that? For this project, I tried to be really careful and it worked out OK, but I wondered how you guys working on stuff that is not as tolerant as the finger engine is, got the job done.
I used the dividers with the bent end (herma....?) and layout dye. It worked well but I found out, don't keep scratching or you get more lines than you need. :o

Well, I am sure some are snickering at my inexperience. That is good. The project was fun. Now I think I might order some real flywheels and see if it makes a difference, and tackle one of the small engines that PM sells.

Thanks and cheers,

Shawn

ShawnR
02-11-2007, 12:07 PM
My husband made me a finger engine for my grade 6 class. In grade 6 students have to classify different motions as being either linear, reciprocating, rotational or oscillating. Then they study (and build) devices that use one type of motion to produce another (so we look at engines quite a bit).

I'm wondering what type of motion you would classify the lever on the finger engine as? At first glance we want to say reciprocating because you use your finger to push the finger pad up and down, but because it has a fixed point in the centre of the lever (the screw) is it an oscillating motion, as it is "swinging" back and forth around that screw (fixed point)?

ShawnR's teacher wife

Lew Hartswick
02-11-2007, 12:57 PM
to: ShawnR's teacher wife

I think the problem may be how to define "reciprocate" and "oscillate" without
also including another descriptor. ie. linear or circular.
...lew... A frustrated pyhsics major. :-)

mlucek
06-07-2007, 06:56 PM
I just ordered a few flywheels from PM Research's web site .... in preparation to build 1 or more of these cute little thangs
OK, I finally built one of these little cuties :D.

Flywheel casting from PM Research (http://www.pmresearchinc.com/store/customer/product.php?productid=3226&cat=34&page=1)

PM Research main flywheel casting page (http://www.pmresearchinc.com/store/customer/home.php?cat=33)

A few pix of mine, turned out pretty nicely. I haven't had the chance to polish it up yet. Stock dimensions from the print.

One change I did was to make brass sleeves/bushings and use socket head cap screws for the pivot points instead of making the brass screw/bushing as called for in the print. I had about 4 weeks left in the semester after finishing my 2nd steam engine, so that was a lot simpler and faster since I wanted to finish this engine by the end of my shop class semester (this week).

Another minor change you can see in the 2nd picture was to use a set screw on the flywheel, this way you can experiment using different flywheels very easily. I used an 8-32 set screw, bit overkill but easy to find.

You might also consider using a bigger set screw on the small steel pivot/eccentric plate (or whatever it's called) on the other end of the flywheel axle. The 4-40 set screw takes a rather tiny allen wrench something like 0.050 that can get lost very easily. Though I'd check the larger hole diameter 1st to see that a bigger set screw would fit in the plate thickness. I don't remember if it was 1/8" or 1/4" ??

http://lh5.google.com/image/ChooChooMike/Rmh2ld-jRLI/AAAAAAAAAAk/JowbKsMkdN4/s400/C%3A%5CMike%5CPix%5C062007%5Cfingerengine01.jpg"

http://lh5.google.com/image/ChooChooMike/Rmh2ld-jRMI/AAAAAAAAAAs/oVOIYEghwpQ/s400/C%3A%5CMike%5CPix%5C062007%5Cfingerengine02.jpg"

http://lh5.google.com/image/ChooChooMike/Rmh2ld-jRNI/AAAAAAAAAA0/aAQt1t2bo7w/s400/C%3A%5CMike%5CPix%5C062007%5Cfingerengine03.jpg"

Here's a short video of it running. (http://www.youtube.com/watch?v=9o4-QGYkGn8)

My first steam engine model. (http://youtube.com/watch?v=kB7EUj63UvY)

My 2nd steam engine model (PM Research wobbler/oscillator) (http://youtube.com/watch?v=CP3lvAoXU_w)

I would highly recommend getting a heavier flywheel than I used. Try a heavier brass one, or at least a larger diameter aluminum one. My engine runs very smoothly, there's very little play and no binding in the axles/joints and everything moves pretty freely. As expected, there are 2 dead spots in the linkage motion used. The flywheel momentum is what's supposed to get the linkage/motion past those dead spots. A heavier flywheel will help a LOT to power past those dead spots (finger lever all the way up and all the way down).

It's kinda fun to try to get a steady rhythm going in either direction. Takes a bit of practice. Incidentally, just pushing down on the lever is a single-acting engine, while pushing down/pulling up on the lever would be a double-acting engine/motion.

My shop instructor is planning on changing the beginning machine shop class project to this finger engine. It's much simpler to make than the C-clamp that's been the stock beginning project for decades. That'll allow more students to finish a project. He's planning on CNC-ing the flywheel so the students get an intro to CNC right off the bat. He'll CAD/CAM it, then have the students put in the aluminum plate and press the start button. I think that's a great idea !

Mike

ShawnR
06-08-2007, 08:24 AM
Nice job Mike.

I have not looked at this thread for some time. Your engine runs much the same as mine. My flywheel might be heavier as I made it from a steel plate with no lightening holes. My wife took it to school for her chapter on Motion. The kids liked having it on her desk. She said they would come up to the desk and just start running it. I have considered some of the other engines that you mentioned too so thanks for supplying the videos.

Shawn

hitandmissman
06-09-2007, 09:41 AM
Good looking project and it would make a fine gift. I just started getting HSM this year. What issue is the plan or drawing in or what back issue should I order to get this. Thanks in advance.

ShawnR
06-10-2007, 09:20 AM
Hitandmissing

If you go back to the beginning of this thread, you will see some comments on this project. The issue is May/June, 2006

Good Luck

Shawn

mlucek
06-12-2007, 02:12 AM
Nice job Mike.

I have not looked at this thread for some time. Your engine runs much the same as mine. My flywheel might be heavier as I made it from a steel plate with no lightening holes. My wife took it to school for her chapter on Motion. The kids liked having it on her desk. She said they would come up to the desk and just start running it. I have considered some of the other engines that you mentioned too so thanks for supplying the videos.

Shawn
Thanks Shawn ! It was a nice ending to this semester's shop class :)



Good looking project and it would make a fine gift. I just started getting HSM this year. What issue is the plan or drawing in or what back issue should I order to get this. Thanks in advance.

Like Shawn mentioned May/June 2006 HSM. It's only 2-pages, 1-page with pictures/text and 1-page drawing.

It's a nice simple project !! I highly recommend it !!

Mike

lugnut
06-14-2007, 08:32 PM
I just finished my version of a finger engine. I didn't have any drawings or measurements so I used Sprocket’s and mlucek’s photos as a guide. The flywheel I machined from a cutoff of 6061 four-inch shaft that I picked up on ebay. The rest is cut from a piece of 1” square 6061-bar stock. The top hat brass bushing are made from some old worn out air fittings. The bearings on the main shaft are from skate board wheels. Fun project to do. Thanks for putting me on to it.
Mel
http://img.photobucket.com/albums/v671/lugnut/010198019Small.jpg

mlucek
06-15-2007, 07:29 PM
Nice job !! Great project cause nothing is really that critical here.

Pretty soon we're going to have to have a Finger Engine Maker's convention of some sorts LOL :D

lugnut
06-16-2007, 10:05 PM
Mlucek, I think the length of the linkage arms are the cause of any dead spots in your engines motion. Try adjusting the length with some arms made from some scrap pieces to see if it will smooth out some.
Mel
:)