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TeaMan
01-07-2013, 10:22 PM
Hello everyone. I'm new to this forum and machining in general. I have a ShopMaster 3 in 1 machine and need some help with it. My interests are Archery, firearms, and cars. The machine isn't what I thought it would be, but I have what I have.

Hopefully this post isn't duplicated. I got logged off before I could send the last one, so it was lost.

1. I have been doing a lot of reading. I have a book "Machine Shop Essentials" that has been helpful as well as forums like this. The book shows the turning lathe running counter clockwise in forward. This turns the work into the tool top to bottom so the chips come off the top. My machine runs clockwise in forward. It turns the work against the tool from bottom to top, so the chips come off the bottom. Which direction should the machine run in when cutting?

2. My machine came with three carbide tools, they are 1/2" shank. When I put them in the toolpost, they are about .231" above center. Should I be trying 1/4" tools and mount them so they cut with the cutting face up and the machine running counter clockwise?

3. My machine has belts to change speeds. The charts on the machine show it to be adjustable from 80 to 1200 RPM with the low speed belt tightner, and 145 to 2160 RPM on the high speed adjuster. I tried it at 2160 RPM since my reading said carbides should be run faster and the machine obviously can't handle this speed. The motor kicked the breaker once and just plain stopped a second time. The 1.5HP motors don't have enough torque. With this in mind, would it be smarter to try HSS tools instead?

4. Tools. Can anyone recommend a good starter set of tools for me. I don't know anything about tools so I'm at your mercy. I read they have styles from A to H. Not sure what the advantages of each of them is. Also what angles and types such as left, right, thread cutting. Any help is appreciated. I also have not found a good source to purchase them, nor what good pricing is. Could anyone recommend sources also?

5. Vise. My machine was supposed to come with a vise, but did not, so I'm looking for a good one that won't break the bank. I found a few on EBay, but am not sure what I'm looking at. Could anyone recommend a good size vise for my machine. I have found 4", 5" and everything up to 8". I'm thinking more like 4" or 5", but again don't know much. Also, would having a swivel vice be advantageus?

6. level. This is again something I don't know anything about. I have roughly leveled my machine, but don't have a machining level. Can anyone recommend a good machining level for my home shop?

Thanks in advance for the help.
TeaMan

Mike Amick
01-07-2013, 11:19 PM
wow .. its refreshing to see someone even greener than I am .. grin ..

I also have a shopmaster (2000) without quadralift. I have installed variable speed DC motors and a DRO

1. no .. the normal operation is CCW with the work coming down into the tool. But you have a
reverse button .. someone just hooked it up backward.

2. You haven't said what type of tool holder you have .. Most would agree to get a QCTP
quick change tool post .. you want the AXA it will take 1/2 " cutter.

3. Generally ... carbide is for steel .. and HSS is for Aluminum and while thinking about that ..
as far as endmills go ... 2 flute for Aluminum .. and 4 flute for steel. This is the quick answer
and is not written in stone.

4. Lots of places to get some starter tools ... http://www.cdcotools.com/ comes to mind
at your stage of the game

5. Here is where I made my big mistake .. If you get a junk vise .. you can forget about
consistent accurate results. I'm not saying the you have to get a Kurt .. but .. get the
best lockdown vise you can afford. 6" is a little big .. but .. you could go with a 4" and
maybe even a 5".

6. Leveling your machine is important .. but .. spend your money on stuff you really need.

anyways .. welcome
Mike

2ManyHobbies
01-07-2013, 11:33 PM
Milling speeds depend on the number of flutes, material being cut, and tool diameter. With limited power, one sacrifices tool diameter and/or depth of cut.

Start with the manuals. They should be able to help you get everything dialed in. If something doesn't make sense, then post back and attach pictures if you can (there is a thread on how to do this back in the topics list). Some of the tooling is custom though you could probably use standard tooling if you want. There will be plenty of people here that can help from a picture even if they don't know the custom tooling.

As far as the cutting upside down? I wonder if that is related to why the tools seem so high and off-center.

Ian B
01-08-2013, 01:29 AM
TeaMan,

Welcome. There's lots of information on the web about basic machine operations - here's an example: http://www.bbssystem.com/manuals/Lathe-Tutorial.pdf

It's not specifically for a 3 in 1 machine, but it contains a lot of good, basic information that'll get you started. Others, I'm sure will have more links to tutorials etc.

Certainly, start out with HSS tooling. Buy blanks and a bench grinder, grind your own from scratch. They'll work fine, and you'll learn a lot about what cuts well, what doesn't. The carbide tools that came with the machine - they're the type where the carbide is brazed to a steel shank? I've had these over the years, and they normally gather dust. A handful of cheap HSS blanks will get you a lot further. You can certainly buy sets of tools - Ebay is always a good source.

And yes - the work should normaly rotate towards you (counterclockwise if you're looking from teh tailstock end), and the cutting tip should be at centre height. Put the centre in the tailstock, use this to set the tool cutting tip height. There are many different ways to set tool height, but this'll work fine.

Don't worry about levelling the machine - really, it doesn't matter too much. You could bolt it to the wall, it'd work just as well. More important is that it's stable, and all the feet are in good contact with a solid surface. Bolting it down to something solid (a lump of steel I beam for instance) would probably help to reduce vibration and chatter.

Good luck,

Ian

darryl
01-08-2013, 03:48 AM
Level in a general sense means that the liquid in a cup of water sitting 'level' won't be slanted to one side or the other. Level in the machine sense is assuring that the front and rear ways that the carriage rides on are in the same plane- in other words, the bed is not twisted. It can be out of general level to some degree and not affect anything, but if you were to place a precision or high sensitivity level on the front and rear ways, the reading should be the same. A typical level is not sensitive enough to give this indication.

My opinion is that you have more to learn before you need to concern yourself with this. About all that you should take into consideration at this point is if you go to bolt the machine down, you should shim the mounting points until the machine does not rock at all before bolting it down. If it does rock, and you bolt it down, you're going to be introducing twist that probably will give a worse error than it may currently have.

You could begin by checking the stand and shimming the feet so the stand is generally level, and doesn't rock at all. A carpenters level is all you need for this.

SGW
01-08-2013, 05:12 AM
Books are your friend.... These aren't' specifically for a 3-in-1, but you might want to find "How to Run a Lathe" originally published by South Bend Lathe, and "The Amateur's Lathe" by L.H. Sparey. Both are fairly old and a bit dated, but there iis still a lot of good basic information in them. Go to Amazon and search for "Workshop Practice." It should display a set of books about various workshop topics. I've bought a few of them and they have all been good.

I suggest you use HSS toolbits. You'll need to learn to sharpen them, but it's a useful skill. You'll need a 6" bench grinder, and you will probably want to replace the wheels that come on it with better ones, but you can get by with the originals.

You'll have much better luck at slower speeds.

You will (or do) undoubtedly feel overwhelmed by your seeming stupidity and the vast amount you need to learn to be able to do anything. I know I did. When I was just starting I was acutely conscious of a lack of traction -- I was so ignorant I didn't have any reference points to build my understanding on. So I read books. I subscribed to magazines (that's a plug for our BB hosts), and gradually built up knowledge. This hobby is a great one for teaching patience. And humility. And there is always more to learn. I've been doing this since about 1978 and on occasion I still feel pretty dumb. Don't be afraid to make mistakes. All of us have a box of "learning experiences" somewhere.

dian
01-08-2013, 06:08 AM
"The motor kicked the breaker once and just plain stopped a second time. The 1.5HP motors don't have enough torque."

this is very weird. it is a very powerfull motor for this machine, so this really shouldnt happen. what diameter were you cutting, were you cutting at all?

TeaMan
01-08-2013, 09:27 PM
Hey, thanks for all the replies and great advice.

There were several questions and points and I'll try to address them all.

mikeamick, once I figured out the machine was working backwards or the FWD / REV switches were wired backwards, it's simple enough to run in reverse making it operate in the proper direction. I also have DRO, and got the CNC too. I decided to learn more about the machine before I install them. I suppose the DRO wouldn't hurt, but I need to know more about the machine before I attempt CNC.

What does AXA mean? I have pictures of my machine from behind showing the toolpost as well as the threading bit mounted upside down showing how it's at center on a piece of aluminum. Another picture shows the LH cutting bit right side up and you can see how high it is on the aluminum shaft. Both of the tools are mounted as low as they go in the toolpost. I have a third picture from the front of the machine showing more of the toolpost. I don't have permissions to post attachments though. I appreciate any help here.

You mentioned you converted to DC motors and drives. After I prove the machine and I can do I want to do with it, I want to make the same upgrade. If you wouldn't mind sending me a PM with a list of what you purchased to convert. I'd be grateful. It would help me a lot.

Last, you mentioned a little about a vise. Here is a link to one on ebay that is imported. It gives the specifications of it's precision. Not sure what it all means or if it means it's any good at all. Price is about $100 less than a Kurt. Any opinions? http://www.ebay.com/itm/SHARS-4x4-1-8x1-1-4-Lock-Down-Precision-Milling-Machine-Vise-w-Swivel-Base-NEW-/330717190280?pt=BI_Tool_Work_Holding&hash=item4d0047d888 My table is about 8.5 X 18.75" if that matters.

Ian B, I do have a 6" bench grinder but don't think the wheels are up to par to do any sharpening of this caliber. What would you recommend for wheels to sharpen or form HSS bits? My carbide bits are exactly as you mentioned, carbide brazed to a steel shank. You can see it in the pictures if I can get them attached. Hey thanks for the link.

darryl. I leveled the machine as you said with a carpenters level. The machine came with a table with adjustable legs. I used these to get it as level as I could, and made sure all 6 were tight on the floor. The machine feels very stable. If this is fine, I'll run with it that way to learn more before I worry about making it any better.

2ManyHobbles. The manual I got with the machine isn't very good. No setup information at all in it except for a small blurb on threading. I'll need to ask more questions to help me with basic setup.

SGW. Thanks for the tip on the books. I will be ordering them shortly. I do a lot of research for my job as an engineer, so books have always been my friend. You mentioned grinding HSS bits, can you recommend wheels?

dian, yes you hit the nail on the head. The motor is lacking torque for it's HP. Since it's made in China, who knows why. It could be poor windings, or more possibly poor iron. The mill motor smoked the run capacitor on startup so I had to replace that right away. I'd like to upgrade to drives and either AC or DC motors in the future, but need to prove myself and the machine first. The first time it kicked the breaker I was taking a couple thousands off of a mild steel 1/2" bar. Really light work. It just stopped under the load of the machine without cutting at all. The motor was warm but not hot. I'd rather run slower with HSS than replace the motor so I can run faster with carbide. This is one reason I'm not real happy with the machine. It does seem solid and most things seem pretty solid.

TeaMan

TeaMan
01-08-2013, 10:04 PM
I think I have it figured out how to attach the pictures. Here they are:
http://s1277.beta.photobucket.com/user/TeaManMachine/media/IMG_8018_zps413b7fab.jpg.html?sort=3&o=2#/user/TeaManMachine/media/IMG_8018_zps413b7fab.jpg.html?sort=3&o=2&_suid=135769932195209777279351039602

http://s1277.beta.photobucket.com/user/TeaManMachine/media/IMG_8019_zpsab0c128c.jpg.html?sort=3&o=1#/user/TeaManMachine/media/IMG_8019_zpsab0c128c.jpg.html?sort=3&o=1&_suid=135770050455209407878751729743

http://s1277.beta.photobucket.com/user/TeaManMachine/media/IMG_8020_zpsd476c2ad.jpg.html?sort=3&o=0#/user/TeaManMachine/media/IMG_8020_zpsd476c2ad.jpg.html?sort=3&o=0&_suid=135770017323006797196548497952

TeaMan

Fasttrack
01-08-2013, 10:40 PM
Ian B, I do have a 6" bench grinder but don't think the wheels are up to par to do any sharpening of this caliber. What would you recommend for wheels to sharpen or form HSS bits?


A good wheel is definitely worth something but I would say having a wheel dresser and a good rest are worth more than the wheel. A great place to buy tooling is Enco (link below). They typically have sales once a month where you can get 10% off or free shipping or sometimes both. If you search the forum, you'll find that the folks here regularly post the promo codes for everyone to use.

I don't believe Enco carries them anymore, but Camel or CGW is a good brand when it comes to abrasives. I have a 6" Camel 60 grit wheel that gets used the most often. I also have an 80 grit silicon carbide wheel that gets used occasionally for touching up tools after they've been roughed out. It also gets used on harder cutting tools like Rex 95 and Tantung G (two types of "tool steel" used for cutting tools - the word "steel" is used loosely here!).



darryl. I leveled the machine as you said with a carpenters level. The machine came with a table with adjustable legs. I used these to get it as level as I could, and made sure all 6 were tight on the floor. The machine feels very stable. If this is fine, I'll run with it that way to learn more before I worry about making it any better.




Don't worry at all about it. You'd be kidding yourself if you think leveling a three in one machine will make any difference in its performance. The guys here all tried to tell me not to buy one but I was young and eager and broke so I bought a Smithy Midas. It was a decent enough little lathe to learn on but the mill was a joke. I'm sorry you are disappointed in your machine but it's not a surprise and you're definitely not alone! It's a good place to start and once you learn more you can start shopping around for something a little more serious (if you have room for it, anyway).

Leveling machines becomes important when you need a great deal of accuracy or when the machine is very long. A short stout machine like my Smithy 3-in-1 doesn't need to be level to still perform poorly :p :D Leveling with a carpenter's level is good (now drill bits won't roll off the table) but it's not the same as "leveling" by a machinist's standards. For instance, when leveling my nice lathes, I use a "master machinists level" that has graduations on the vial. Each graduation is 0.0005" per foot. The body of the level is heavy and cast iron with a plastic insulator to prevent body heat from changing the dimensions of the level. The bottom is scraped flat (actually they're very slightly concave by design). Also, new, these things cost somewhere on the order of $700 <holy cow!> Not your typical carpenter's level :)


http://www.use-enco.com
Enco has some high quality stuff and some junk from China. I started off buying a lot of import stuff and then, as I learned, I would save up for the high end tools/tooling.




By the way, if you don't mind paying for shipping, PM me your address and I'll put a couple of HSS blanks in the mail. I'll grind one of them to a "standard" turning tool so you'll have something to look at when you go to grind your own later. One of the advantageous to HSS is that you can quickly grind speciality tools. Over the years, I've amassed a collection of turning, boring, threading and facing tools that I've ground for special jobs. I've also got ones ground to make certain size o-ring grooves, snap ring grooves, etc, etc. Having a simple turning one to play with makes the learning process much easier, though. (And you'll have to let me know what size you want - I've got quite a bit of 1/2" on hand and some 1/4" ... have to look a little harder to find my 5/16" and 3/8" though.

Mike Amick
01-09-2013, 01:46 AM
Hey Teaman ...

Once you get into your machine a little .. I can help you with the treadmill conversion .. its actually quite
easy. The CNC can be installed without sacrificing manual use of the machine which is sort of unusual. You will
want to install and appreciate the DRO quickly .. but .. by all means .. learn the dials a little first.

Here is a vid of my machine and the lathe conversion ..
http://www.youtube.com/watch?v=mqZRVOb29u4&feature=plcp

I don't know what the AXA means .. but .. there is AXA BXA & CXA .. incrementing in size. The
AXA is what I have and perfect for your machine. What you have are these tool holders that only
cost about $8 .. each loaded with a different tool (cutter). It only takes seconds to change from one holder
to another one. Pretty neat thing actually.

That vise looks like it would be good for your machine .. take note though that the guy wants like $60
for shipping .. so you may want to look at Enco .. they have a free shipping offer most of the time.
http://www.use-enco.com

All the suggestion about learning are great .. you can't go wrong. I personally love youtube .. there are so
many vids showing how to machine .. its great.

One of my favorites at my stage of experience is Keith Fenner .. the git er done guy
http://www.youtube.com/user/KEF791
He likes to think out loud so you can see/hear his logic.

Another great one is Tubalcain
http://www.youtube.com/user/mrpete222/videos

Anyways .. get your machine set up normal .. go buy some aluminum and steel and stainless rod and
start making chips ..
An hour on your machine will answer about a million questions ... and create 2 million more .. lol
These guys have the patience of saints .. and are as good as it gets knowledge wise .. so you
came to a good place.

Mike

SGW
01-09-2013, 12:16 PM
Re: Grinding wheels.

I do it wrong. :) I use silicon carbide "green grit" wheels for everything. They are meant to sharpen carbide, though to really sharpen carbide properly you need a diamond wheel. Anyway, I find they work well for HSS. They cut fast and don't heat the work as much. They do wear more rapidly. If I were grinding with them for 8 hours a day that might be an issue, but touching up a toolbit once or twice in an evening doesn't wear them enough to matter. I've got #80 and #120 wheels.

andywander
01-09-2013, 12:58 PM
That tool post is one I haven;t seen before.

It appears that the block in which the tool is held is adjustable up and down, but it looks as if that one is all the way down....

There is no reason you can;t use the lathe in REV, though, with the tool upside down.

kwoodhands
01-09-2013, 06:45 PM
Your tool post is adjustable for height. I see a place for a large Allen wrench on the tool post.
Loosen the clamp and adjust the height. Tighten the clamp with the tool at dead center with the spindle. The rotation should be towards you. The tool should be right side up at dead center for almost all work. You do not need another tool post as the one you have looks to be superior to anything on the market.It appears to be very heavy,well built and can hold two different tools at the same time. Both cutters can be adjusted to different heights if needed.I think the tool post was custom made.Maybe by the former owner.
Buy high speed tool blanks and grind your own. McMaster Carr, Enco ,Wholesale tool and Little Machine Shop are just a few online suppliers.
You can buy Pre sharpened tool cutters from Little Machine Shop (LMS). Buy one set of 5/16" square cutters for a sample of how the cutters should look. LMS also has tutorials on grinding the cutters.
mike

sch
01-09-2013, 06:50 PM
Another resource for the novice, the FAQs on chaski: http://www.chaski.org/homemachinist/viewforum.php?f=44 Lot of dross and sparks there but some useful info.
Here is a primer for HSS tool grinding: http://www.sherline.com/grinding.htm
A 4 or 5" vise is appropriate for your machine, 4" is ~40-50# weight and 5" will be in the 50-65# range. The rotary base is fairly useless and on your machine takes up
valuable vertical space when milling. 6" vise is 80#+ and too big plus expensive to ship. Enco does motor freight for items at the mid and upper end of UPS weight range
which makes shipping prohibitive for small $ items. The solid shank brazed carbide tools are not very useful and I don't recommend any of the sets of these that are
available. I have a set of 40 I have mostly never used..... http://www.cdcotools.com/ is a reasonable source for tooling for your machine and the AXA holder is on their
home page. The $30 insert carbide tool sets (such as the indexable turning set under cutting tools on the CDCO site) are only marginally better as the inserts are not
very high quality. www.carbidedepot.com is a site with much better inserts. Grinding 1/2" HSS tool bits is a chore, even with a good grinder, you would do better with
3/8" HSS blanks. The sherline site is a good start for grinding your own. The Shoptask/Master doesn't have a halfnut so manual threading is dicey, not to mention 80+RPM
is a little fast for manual. The CNC will make short work of threading, if you get around to that though. In short, start with HSS tool blanks in the 3/8" size for your tooling
and learn to grind tools. Your machine doesn't have the speed needed to make carbide on aluminum happy though it is up to carbide tooling on steel. Chinese or Indian
HSS tool blanks are usually acceptable metallurgically. You will have to hunt to find US or European tool blanks and they will be pricey (though victornet has some 5/8" Rex
tool blanks for $3.50, they are too big for you).

As to books: try www.abebooks.com and search on Steve Krar "Technology of Machine Tools" the text not the workbook, an older edition is fine and will be under $20 (new
current edition is $140 or so). Haven't seen the workbook but I used the text for my CC course and it is comprehensive for manual machines. Mine is the 5th edittion.

An omnium compendium site for 3n1 is on Yahoo groups: http://groups.yahoo.com/group/3_in_1_Lathe_Mill_Drill/ Particularly look under the files and links section.
Another site: www.cnczone.com scroll way down in the forums for the Shoptask group.

Mike Amick
01-09-2013, 08:09 PM
I agree with Sch .. if you can get that tool post to the right height .. I would use it. Nice and solid
looking. From the peeks I got from you pics .. it looks like you have a quadralift. This makes the
mill much more rigid than a normal 3_in_1. Normally the mill is hanging out in space and flexes like crazy ..
the quadra fixes this. It also has the benifit of giving you a decent range of mill head height movement.
I don't have this on my shopmaster and my work is always too high or too low .. so much so that I
bought a big ol knee mill to cure this ...

For the guys that arn't familiar with the quadralift .. you can see what I am talking about on the
home page of the shopmaster site. If I could only have one (hobby) machine .. this would be it.

http://shopmasterusa.com/

You can call or email those guys .. and a guy by the name of JT will be more than willing to help.

Mike

TeaMan
01-09-2013, 11:16 PM
Thanks again everyone for the great responses and feedback. There are a couple clarifications and questions I'll answer. First on the toolpost. This toolpost came from ShopMaster with the machine. I am the original owner of the machine and it's technically brand new. I've had it for about 3 years, but it's been in storage up until the last 3 or 4 months. If you look at the pictures, there is an allen bolt that can be loosened which I have done. The top of the tool holder has a shelf that bottoms out on the top of the toolpost. This stops it from going down any further and with the tool right side up, it is about .231" above center with a 1/2" tool mounted which is what came with the machine. This is the tool shown in the pictures. I see a couple possible solutions. First, I could take the toolpost off it's mount, turn it upside down in a vise and use the mill to remove about 1/4" from the bottom lowering the entire toolpost. Second, I could take each of the 4 tool holders and put them in a vise and remove about 1/4" from the shelf at the top. This would reduce the amount of material that the adjustment screw has that you can see in the pictures in the center, but there is no force on the screw, so that may not be a problem at all. Third, I could just try a smaller tool, probably in the 1/4" range to see if it would drop things into place. I suspect this solution would limit me to HSS tools and eliminate the use of an insert holder. I think the insert holders are larger in diameter. One of the 4 tool holders has a "V" cut on bottom which I have to assume is to hold a round shank tool like a holder for inserts.

Any suggestions on this?

There were lots of suggestions for youtube videos and other web sources as well as books. All great, and again thanks. The one for video's from Keith Fenner, he's not only informative, he's entertaining which makes it even better. There were others that were excellent also.

I played with the machine a little more tonight and found that my reverse which is actually forward runs the machine much better than running it in reverse or clockwise. The belt tightner has issues moving the machine in the clockwise direction. It doesn't want to grab well, probably the torque on the pulleys and position of them with respect to the tightners. With this in mind, I'd really like to figure out how to run the machine counterclockwise or the direction it seems from feedback I've gotten, is the correct direction.

I do have a question about speed and tools I'd like to get clarified. It was my understanding from the reading I've done that the main difference between using HSS and Carbide is the speed at which you turn the work. My understanding was that HSS had sort of a sweet spot for steel and one for aluminum which could be somewhat machine specific, and carbide should run 2 to 3 times faster, and was mainly used to gain productivity. Help me if I'm wrong here. Could anyone comment on what those sweet spots are for steel and aluminum, at least general starting points?

The consensus seems to be with HSS especially for hobby and a home shop and learning to grind them. This is new to me, but I'm more than willing to try. I'll order a couple good wheels for my grinder and definitely give it a shot. I do have to figure the tool post out and find the proper size of tool to start with though.

Mikeamick, I'm definitely interested in your conversion to the drive. I think you only did it on the lathe, and I'd like to do it on both the lathe and the mill. I do have the extra arm so my mill is supported with a bridge. I think ShopMaster calls it a BridgeMill. This does give the mill lots of support although I haven't messed with it yet. I need a vise to make it more useful. My belts and pulleys on the mill are also way out of alignment, so I have to deal with that first. Shouldn't be a huge deal though.

Last, sch, what is a halfnut and what does it do? You said the shopmaster doesn't have on, but I'm not even sure what it is. Mostly curious.

Thanks again.
Teaman

Fasttrack
01-09-2013, 11:56 PM
I do have a question about speed and tools I'd like to get clarified. It was my understanding from the reading I've done that the main difference between using HSS and Carbide is the speed at which you turn the work. My understanding was that HSS had sort of a sweet spot for steel and one for aluminum which could be somewhat machine specific, and carbide should run 2 to 3 times faster, and was mainly used to gain productivity. Help me if I'm wrong here. Could anyone comment on what those sweet spots are for steel and aluminum, at least general starting points?


Have a look here:
http://www.southbaymachine.com/setups/cuttingspeeds.htm

Cutting speed and feed tables can be found in the "standard" reference book: "Machinery's Handbook". The rpm at which you turn is dependent on the work diameter so cutting speeds are typically given in surface feet per minute rather than RPM. You then have to determine the best rpm by dividing the SFPM by the circumference of your work piece.

The consensus seems to be with HSS especially for hobby and a home shop and learning to grind them. This is new to me, but I'm more than willing to try. I'll order a couple good wheels for my grinder and definitely give it a shot. I do have to figure the tool post out and find the proper size of tool to start with though.




Last, sch, what is a halfnut and what does it do? You said the shopmaster doesn't have on, but I'm not even sure what it is. Mostly curious.



A halfnut is used for threading. Basically it's a clutch that allows you disengage the carriage while the machine is still turning. It is used in conjunction with a "thread dial" which is basically an indicator that lets you know when to "close" the halfnuts to pick up the thread again.

Why is this useful? Well, think about trying to cut threads to a shoulder. You can't cut a thread in one pass so you will have to stop the carriage, retract the cutting tool, return the carriage to the start of the cut, move the cutting tool back in and take another pass. With halfnuts, you leave the machine on all the time and you can stop the carriage at exactly the same place each time. With these 3-in-1 machines, it's very tricky because the best you can do is shut off the machine and let it "coast" to a stop. You always run the risk of overshooting the shoulder and crashing the tool bit into the shoulder - resulting in a great deal of cussing. I found the best way to avoid this problem was to shut if off early and turn the chuck by hand the last couple of revolutions - it sucks but it's "safe". Also, without halfnuts, you will have to retract the tool and then run the machine in reverse to return the carriage before proceeding with another pass. You MUST retract the tool. The backlash in the leadscrew will kill your threads if you try to cut in both forward and reverse.

By the way, this "clutch" is referred to as a halfnut because it is basically two pieces of a nut that get clamped together around the threaded leadscrew. For a visual example, here is a picture showing the half-nuts on my Pacemaker lathe as I disassembled the apron.

http://i108.photobucket.com/albums/n22/fasttrack237/Pacemaker/100_0555.jpg

mixdenny
01-10-2013, 10:48 AM
I do have a question about speed and tools I'd like to get clarified. It was my understanding from the reading I've done that the main difference between using HSS and Carbide is the speed at which you turn the work. My understanding was that HSS had sort of a sweet spot for steel and one for aluminum which could be somewhat machine specific, and carbide should run 2 to 3 times faster, and was mainly used to gain productivity. Help me if I'm wrong here. Could anyone comment on what those sweet spots are for steel and aluminum, at least general starting points?


I have the same machine with Quadralift and my own bridgemill conversion. I use carbide all the time. carbide does not need high speed, it simply allows high speed, which makes production faster. I'm currently making 8 rollers from 6061 aluminum 2 1/8" diameter. The lathe was set at 352 rpm, so I used it and am getting mirror like finishes.

As for books, there is one and only one for the Shoptask. "Precision Rifle Rebarreling and Case Preparation on a Home Shop Lathe" by John Stranahan. Don't worry if you are not planning rifle work, as the book has an extensive and precise method of aligning everything, plus innovative fixturing photos. Unfortunately, it appears his web site is gone, so you may need to hunt down a copy, you will not regret it.

The bridgemill will probably need to be trammed after you moved it to your place. You must do it in the following order. First, make sure the Quadralift moves straight up and down, in both planes. Measure this with a dial indicator mounted on the spindle and indicating against a good angle block. If it needs correcting, place shims under the Quadralift bottom plate. Then tram the mill head using normal means, ie, swing a spindle mounted indicator around in the circle, with the tip on the table. (Lift it over the T slots). Loosen the bolts holding the mill head in between the two mounting plates and gently tap it around. It is unfortunately not very precise, and may take a lot of fussing to get right. It tends to move back when you tighten the bolts, shims can help.

Finally, make sure the mill head does not shift when you tighten down the sliding clamp on the bridegemill post.

Dennis

mixdenny
01-10-2013, 11:02 AM
A halfnut is used for threading. Basically it's a clutch that allows you disengage the carriage while the machine is still turning. It is used in conjunction with a "thread dial" which is basically an indicator that lets you know when to "close" the halfnuts to pick up the thread again.

Why is this useful? Well, think about trying to cut threads to a shoulder. You can't cut a thread in one pass so you will have to stop the carriage, retract the cutting tool, return the carriage to the start of the cut, move the cutting tool back in and take another pass. With halfnuts, you leave the machine on all the time and you can stop the carriage at exactly the same place each time. With these 3-in-1 machines, it's very tricky because the best you can do is shut off the machine and let it "coast" to a stop.


The Shoptask does not have half nuts in the carriage. It disengages the leadscrew with sliding gears in the headstock with a handle which has forward, off and reverse positions. It stops the feed instantly. It has a an auto-stop feature which will disengage the feed at whatever point you set it. Because of this setup, the Shoptask uses completely a different threading procedure which does not use a threading dial.

Dennis

Fasttrack
01-10-2013, 01:59 PM
The Shoptask does not have half nuts in the carriage. It disengages the leadscrew with sliding gears in the headstock with a handle which has forward, off and reverse positions. It stops the feed instantly. It has a an auto-stop feature which will disengage the feed at whatever point you set it. Because of this setup, the Shoptask uses completely a different threading procedure which does not use a threading dial.

Dennis

How do you pick the thread back up again? My Smithy is the same way; it has a lever with forward, reverse and off but there is no way to pick up the thread in the proper place so you have to leave the leadscrew engaged the whole time.

mixdenny
01-10-2013, 03:22 PM
How do you pick the thread back up again? My Smithy is the same way; it has a lever with forward, reverse and off but there is no way to pick up the thread in the proper place so you have to leave the leadscrew engaged the whole time.

Put a mark on the chuck perimeter (anywhere) and a matching mark on the headstock. Set the auto stop for the start and the end of the threading run. Engage the leadscrew, release the spindle brake (the Shoptask is the only 3 in 1 with a spindle clutch/brake) and run the thread. It will disengage the leadscrew at the end of the thread. Back out the tool, feed backwards until the autostop kicks out. Stop the spindle and rotate the chuck until the marks line up. Engage the leadscrew. Repeat. It sounds odd because it is different, but it goes like clockwork once you get used to it.

By the way, it uses this unusual feed method because the Shoptask has been setup for CNC since at least 2000. This permits the CNC motors to hook directly to the headstock end of the leadscrew. All you need to do is add the motors and controller.

I think the Smithy would work the same, except you would have to stop the motor, not the spindle. The carriage has to return to the exact same starting spot each time (you would need to set up a dial indicator, or use a DRO). The autostop and spindle brake makes it much faster.

Dennis

Fasttrack
01-10-2013, 04:34 PM
Put a mark on the chuck perimeter (anywhere) and a matching mark on the headstock. Set the auto stop for the start and the end of the threading run. Engage the leadscrew, release the spindle brake (the Shoptask is the only 3 in 1 with a spindle clutch/brake) and run the thread. It will disengage the leadscrew at the end of the thread. Back out the tool, feed backwards until the autostop kicks out. Stop the spindle and rotate the chuck until the marks line up. Engage the leadscrew. Repeat. It sounds odd because it is different, but it goes like clockwork once you get used to it.

By the way, it uses this unusual feed method because the Shoptask has been setup for CNC since at least 2000. This permits the CNC motors to hook directly to the headstock end of the leadscrew. All you need to do is add the motors and controller.

I think the Smithy would work the same, except you would have to stop the motor, not the spindle. The carriage has to return to the exact same starting spot each time (you would need to set up a dial indicator, or use a DRO). The autostop and spindle brake makes it much faster.

Dennis

Sounds like there are a lot of places to introduce error, especially when cutting fine threads. (Which is a fancy way of saying it sounds like there are a lot of places a guy like me could screw something up - no pun intended!) I think I'll stick to my half-nuts and 1940s machines :)

2ManyHobbies
01-10-2013, 05:25 PM
Okay, after looking at the pictures of the toolpost I see 2 things.

1) The cutting tools are too big. Smaller shanks would dial in properly.
2) The upside down tool is compensating for #1. This is okay if the carriage is designed for that. Some machines use an upside down parting blade that engages the work when the usual toolpost is backed away from the work.

I have a 1/4" air gap above a 1/2" tool shank for comparison.

TeaMan
01-10-2013, 10:06 PM
Thanks 2ManyHobbies. Looks like I need to try 1/4" tools. I think 3/8" would be too high also, but will use a center and measure this weekend to be sure.

What did you mean by your last line in your post? "I have a 1/4" air gap above a 1/2" tool shank for comparison. "

TeaMan

2ManyHobbies
01-10-2013, 10:23 PM
The slots in my 4-way toolpost are nearly 3/4". With a 1/2" shank I have about 1/4" of air to the top plate that contains the tool retention screws.

2ManyHobbies
01-11-2013, 12:24 AM
Thanks 2ManyHobbies. Looks like I need to try 1/4" tools. I think 3/8" would be too high also, but will use a center and measure this weekend to be sure.
I looked at your pictures again but can't tell enough to be sure...
The shank of the tools are 1/2" right? How much higher is it with the brazed on carbide tip?

The Shopmaster website says it can use lathe tools from 1/4" to 1/2", so my thought is that the carbide may be putting you up higher than your machine can handle.

I wonder if they created specs so that it can hold a 1/2" tool but the tool profile has to have a lowered or recessed contact point. It is clear from the photos that the tool holders won't go down any lower. I don't want to tell you to go mill some of the top off of the toolpost so the holders can drop down farther, but that almost looks like an option. :confused:

Deja Vu
01-11-2013, 10:14 AM
I don't want to tell you to go mill some of the top off of the toolpost so the holders can drop down farther, but that almost looks like an option. :confused:
I have the same tool holders/post on my shoptask. I DID mill the top surface down off the post to allow the holders to drop lower. However, I only needed an eigth inch. The base/bottom looks like it could be shaved off some too.
The holder securing screws on yours seem to be located lower on the post so you may be able to take more off the top.
I did the milling while the post was secured and just milled around the post nut on top with the handle removed.

My compound has a lower profile than yours.
Shoptask rebuild: note.... some pics no longer appear on first few posts. Pics start in post #33
http://www.cnczone.com/forums/showthread.php?t=2139

Home built gantry router:
http://www.cnczone.com/forums/showthread.php?t=5049

TeaMan
01-11-2013, 08:00 PM
2manyhobbies: The pictures don't show it well at all, but the carbide is even with the top of the tool. The shank of the tools is 1/2". What is strange to me is these tools came with the machine, but they don't appear to fit. The manual for my machine says the toolpost will handle tools from 1/8" to 5/8". Not sure I trust the manual it doesn't match my machine exactly. For instance it describes a chain driving my lathe, and I have a toothed belt.

I didn't think of milling the top off the toolpost. That is an interesting option.

Deja Vu: Nice machine. It is slightly different than my machine. I like your handles more, especially the one for your mill. Mine are not quite as nice for some reason.

I see you got both DRO and CNC with your machine. I ordered both with mine too, and neither were installed. I didn't get a manual explaining how to install either. Did you? I emailed shopmaster, but don't have much luck with the support. It would be nice to have a reference, rather than have to poke at it myself until I get it figured out.

Also, what shape were your shifters in that move the tables in the X and Y directions. Mine almost wouldn't move and they were installed backwards, the ecentric inside was upside down so they moved the tables in the opposite directions they should. The auto stop would push the lever in the direction it was in causing it to engage, not disengage. I took it all apart, worked it a lot, cleaned and lubed and now am rebuilding the essentric and shafts to make it fit tighter. My shifter that engages the gears in low or high speed (threading gears) is also way off center. It touches the machine in low and is in the center position in high. Center is somewhere in between. It also shifts pretty hard, so I will look into it too. Just messier because that gearbox is full of oil.

It's like they overlooked a lot of things and didn't test the machine like the manual shows they did, or they would have seen these things.

I'd like to install the DRO this weekend but without some kind of instructions, I see a long weekend of fiddling around figuring it out.

TeaMan

Deja Vu
01-11-2013, 09:28 PM
These pics might be large...didn't take time to size. These were some of the pics that don't show anymore in CNCZone's thread as posted earlier.
Aside from some obvious problems upon delivery, I just made everything fit and work properly when assembling. I did a lot of fiddling in the gear box and in the belt pulley area as it went back together..not to mention everywhere else.

But that's alright! I got this at a good price and just wanted to learn as I put it together again.

The CNC and DRO350 were gotten as separate kits to solder, screw and assemble. Heh! I remember I was so green then that Dan Mauch was hesitant to sell me the CNC kit...thinking he would be inundated with support calls from me. ;) But all went well.

I'll see if I have a manual in PDF format...I know I have the binders. I think you might be able to get legacy files from the Shoptask site.
The auto stop was completely removed.

http://memberfiles.freewebs.com/78/43/42124378/photos/Shopmaster/PDRM0004.JPG

http://memberfiles.freewebs.com/78/43/42124378/photos/Shopmaster/PDRM0023.JPG

http://memberfiles.freewebs.com/78/43/42124378/photos/undefined/Down%20the%20steps.jpg

TeaMan
01-11-2013, 10:18 PM
Wow, I thought I had ambition. That is a real pile of parts. I should really take your lead and do the same. I know the machine needs lots of work to make it work right. Too bad a person has to do it to a new machine. I keep thinking if I purchased a new car would I expect to take it home and disassemble it, fix a bunch of things and reassemble it. Sounds kind of bad thinking of it that way. I got a deal on mine too, but JT doesn't seem to want to support it either. Maybe because of that.

TeaMan

Deja Vu
01-11-2013, 10:21 PM
I tried to approach the machine like an elaborate lego display model that I got off the shelf at a reduced price.:D

But it really does perform well now since I got to know it inside and out. It did great making all the parts that required machining for the CNC router table build.