Bought my first lathe - tooling question

[stioc]

After years of wanting a lathe I finally bit the bullet and picked up a 7x10 mini lathe from HF http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93212

I want to buy a couple of basic tools/bits locally so I can play with the lathe this weekend - I'll order the nicer tools from littlemachineshop.com later. However, I'm a total noob I'm not sure which tools from HF are the correct size for this lathe (1/4", 5/16", 1/2" etc)

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=40637

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=39933

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90742

 

[rsanter]

you see the tool holder on the lathe.....
measure the area where the tooling would go and that size or smaller will work for you.
by eye it looks like 1/4 and/of 5/16

bob

 

[Uncle Buck]

you see the tool holder on the lathe.....
measure the area where the tooling would go and that size or smaller will work for you.
by eye it looks like 1/4 and/of 5/16

bob

You can bet given the size of the machine it will be one of those two for sure.

 

[sk farmer]

1/4, 5/16 way to big for that baby.

 

[stioc]

Based on what I've read so far about these lathes it points to 5/16 "blanks". So say it's 5/16" I figure 1/4" should work just as well kinda like running a 3/8" drill bit in a 1/2" chuck, am I right?

 

[toolchaser]

As long as you can get the top edge of the tool bit up to the center height of the lathe I.E. the point of the center

 

[jeffg]

you need 5/16 tools for that lathe. You can use 1/4 but you will need to fabricate a shim to go under them. The cutting edge of the tool needs to be on the centerline of the lathe.

Do some searching on Google for mini-lathe. there are a lot of people that use this lathe and have done some cool projects that will make you life easier. Carriage stops, tail stock clamps, etc.

 

[independentrider]

you need the tip of the tool to run just below center of whatever your turning. I looked into these lathes before and i'm 99% sure its the 5/16. it should tell you in your operators manual. also if your gonna mess around will aluminum get high speed steel tools

 

[Kevin54]

Indexable inserts will give you three or six cutting edges depend on the rake of the insert. But you will have to find a place to order the inserts plus the fact that the inserts themselves can tend to be a little expensive. The first pic you showed of the 1/4" carbide inserts will get you by, but if you don't have the tool set correctly, go past center, get a hard spot in material, you can ruin the tool. If id doesn't break the carbide completely you can resharpen it. BUT you need a diamond wheel on a bench grinder to do it as carbide is hard as Kelseys nuts. Also carbide is very brittle. For $5+ for a 5 pack of bits, the carbide is probably very low grade. You may want to pick up some High Speed Steel bits and learn how to sharpen them. You can get them very reasonable from Flea Markets, Swap Meets, CL, etc. Do not pay a lot for HSS. Also check www.practicalmachinist.com for tips on running a lathe. Lots of good info there and also there are quite a few machinist here that can answer questions for you.

 

[Diesel_Crawler]

It's more of a piggy bank then lathe.

I don't know after having a lathe that can take 3/4 of an inch in one run I do not think I could handle not breaking that one. But for just starting out and toying around should be great for you

What you need is one of those nice one's they use at the ship yards, were you get to sit down right on the tool post and go with it.

 

[stioc]

Thanks for all the tips and info guys. I picked a 5 carbide bit set, just got done cleaning the lathe (it was covered in red grease) and playing with it for a little while. I have to say I really didn't have a clue what I was doing. I chucked up a small piece of 1" OD steel pipe, screwed down the carbide tool btw I didn't know exactly which way they go they all have different shapes, I put the tip side down and started turning the knobs. It was slow going...for some reason I expected it to cut a groove into the pipe and face it square quickly but took a while. Also at times I wondered if I was pushing the tool in hard enough or too hard to ruin the motor's ball-bearings. I guess I'll go bug one of my neighbors tomorrow and see if he can show me the basics. He used to be a toolsmith for a medical company and still has a full shop in his garage.

DC, that's one huge lathe! something tells me I'll never need one that big.

 

[rsanter]

the guy that taught me machine work used to operate a lathe with a 10 or 12 ft turning capacity.
the guy also has made some of the parts for the original mars lander from the 70s

bob

 

[A_Pmech]

Russel,

For a machine of that size and weight, I'd use only dead sharp HSS toobits, ground for the application, then honed. That type of machine isn't very ridgid, so a dead sharp grind with zero nose radius will keep the tool load down.

Blanks can be purchased from any machine shop supply. I use Victor Machinery Exchange in NY city fairly often. MSC is another good source.

You should locate a copy of South Bend's book "How to Run a Lathe". I believe Gingery re-published it. All you need to know is contained within.

 

[Kevin54]

Russell.........the carbide tip goes up or to the top. The carbide tip is your cutting edge. Also when you set your tool, you want the tip of the tool at the center of your pieve you are going to cut. It is hard to tell with a piece of tubing, but if you had a solid piece in the lathe, you can turn the lathe on and take a pencil and kind of mark center while it is running. This gives you a visual to go by to start to set your tool. Once you get it set you can start to go across the face. When you get close, you can see whether the tool needs to go up or down to center it. If you are too far down, the piece will want to walk over the top of the tool and break it. If it is too high, you will not be able to cut as the closer you get to the center, your tool will be cutting on the side of the tool and not the top edge. And as I stated, check out practional machinist as a lot of time there are video clips of different things going on that you can pick up on.

One other thing that may help immensly....do a searh for "metal lathe" or "lathe turning" on YouTube. I just did and a lot of clips show up.

 

[rjspitz]

Congrats man!! I've got the HF lathe too. I've found that it's a real stress reliever to just sit behind it and cut some stock.

1/4 or 5/16 tools will work just fine, just need to shim them.


Here's a few Titanium rings I've made for my girlgriend to sell at her craft shows.

 

[A_Pmech]

"How to Set Tool Height" or "Another Use for the 6" Rule"

With a lantern-style toolpost every tool change needs a center reference. A quick way to do this is to place your 6" rule between the work and the tool. Lightly apply pressure with the cross feed. If the rule is dead vertical, you're on center. If the bottom of the rule is pointing away from you, the tool is below center. If the bottom of the tool is pointing towards you, you're above center.

With your mini turret-type toolpost, you may find it quicker and more accurate to set the tools to you tailstock center. However, the "rule trick" works well with a little practice.

 

[crashbumper]

You should locate a copy of South Bend's book "How to Run a Lathe". I believe Gingery re-published it. All you need to know is contained within.

If you can't find that, I have a pdf I found from the army. (Uploaded to Box.net, not GJ)

"Training Circular 9-524 Fundamentals of Machine Tools"

309 pages, covers mills, lathes, grinding, drilling, sawing, etc. I like to read it all the time even though I have no lathe or mill.

Training Circular 9-524 Fundamentals of Machine Tools

 

[Uncle Buck]

Here you go, they ought to have some good books aimed at learners.

http://www.lindsaybks.com/prod/index.html

 

[Uncle Buck]

If you can't find that, I have a pdf I found from the army. (Uploaded to Box.net, not GJ)

"Training Circular 9-524 Fundamentals of Machine Tools"

309 pages, covers mills, lathes, grinding, drilling, sawing, etc. I like to read it all the time even though I have no lathe or mill.

Training Circular 9-524 Fundamentals of Machine Tools

That is quite a resource you found there! That would be very beneficial for a new learner. Good stuff indeed.

 

[A_Pmech]

"Training Circular 9-524 Fundamentals of Machine Tools"

Crash, that's a good find! There are several other Army and Navy Technical manuals out there on the subject of machining and machine shop operations.

While trying to find the Army's TM manual server, I found this:

Army Machinist Course - Lathe Operations

More here:

http://opensourcemachine.org/us-army-courses

 

[Uncle Buck]

Fantastic resources guys!

 

[SWA Guy]

Russell,

I used to own a 7x10 mini lathe also, then graduated to a 9x20 and now have my dream lathe - a 1951 Southbend Heavy Ten.

You have already discovered one of the greatest resources for the 7x10, Little Machine Shop at www.littlemachineshop.com.

Another awesome place for information and help with these machines is a Yahoo Group dedicated solely to them. There are more than 7,000 members here - http://groups.yahoo.com/group/7x10minilathe/?yguid=297007105

Good luck and have fun!

Guy

 

[kbs2244]

There is a pretty active yahoo group centered aound that lathe.
Check it out for a lot of info.

The only problem is they seem to put up with a lot of off topic stuff.
But there are some nuggets in the gravel.

 

[stioc]

Thanks guys. I've bookmarked some links and have looked at some youtube videos and even signed up for the yahoo group.

I think my biggest frustration is the cutting speed, it takes forevaaaaar to cut a groove in, I'm sure part of it is me and part of it is the cheap HF bits. I'm not quite to the point where I could cut my own tools yet.

Speaking of cutting do you guys have any online sources for stock material like round bars etc? Any recommendations for the size and material to practice on?

 

[crashbumper]

Any recommendations for the size and material to practice on?

I have frequently seen people in the HF lathe community recommend delrin, aluminum, nylon, etc. as the material is very soft. Easier to get the hang of the machine on something more forgiving.

That being said I do not own an HF lathe, so take that for what its worth.

 

[rjspitz]

Onlinemetals has been my sole source for stock. Good prices and great service. They keep an online history of all orders so you can easily re-order the same material later.

I've practiced mostly on aluminum, but have cut a lot of delrin and titanium. Not too much steel. I've had luck with these HF tools:

The carbide tipped tools are nice too since you can turn the tip 3 times before replacement.

This has been my favorite cutting tool:

Make sure to get yourself a set of center drills and boring bars too.

 

[crashbumper]

This has been my favorite cutting tool:

If you feel ambitious, here is a link to plans on how to build that ball/radius turning attachment.

http://www.metalwebnews.com/howto/baltool/balltool.html

Another version:

http://www.bedair.org/Ball/ball.html

 

[doug.j]

Thanks guys. I've bookmarked some links and have looked at some youtube videos and even signed up for the yahoo group.

I think my biggest frustration is the cutting speed, it takes forevaaaaar to cut a groove in, I'm sure part of it is me and part of it is the cheap HF bits. I'm not quite to the point where I could cut my own tools yet.

Speaking of cutting do you guys have any online sources for stock material like round bars etc? Any recommendations for the size and material to practice on?

I buy from McMastercarr. They are not cheap but they are fast. They have a table that tells you the characteristics of the alloy (machinability, wear resistance, etc.). Avoid using mystery metal until you get a feel for how things should be cutting. Cheap metal with hard spots will drive you mad. The Lowes, Home Depot metal rack is not a good place for getting metal to turn. You probably know that already.

 

[kbs2244]

The best idea I have heard of for just pratice and learning what knob does what was to use scraps of PVC pipe.
You can throw it in the chuck and pratice cutting threads, turning down a dia, whatever.
For between center work it may take a big cone on the tailstock, but that would be a good starter project.

 

[stioc]

wow that ball cutter looks to be the tool someone was using to make weighted shifter knobs on the Miata forum several years ago when I had a Miata - that's cool!

BTW, I forgot to say that's a cool titanium ring...most of my projects are car related but you just gave me an idea. While my wife doesn't tell me not to buy tools every now and then she'll question "what for? you already have so much 'stuff' that you don't really use".

Doug, hahaha the Home Depot metal rack is where I was yesterday looking at what to get. I guess I'll get some aluminum and brass stock so it's easier to cut. The thing with non-steel stuff is that usually I would weld stuff but I can only weld steel with my Hobart...I guess I'll have to put a TIG on my wish list. Until then I'll use the welder that comes in tubes.

Oh yeah I saw a youtube video where someone was using a pvc pipe in the lathe, that's a good idea I'll have to try that.

 

[stioc]

Are there any forums like this one or welding web dedicated to lathes or machining. I'm interested to see what people can do with a lathe. I'd love to see some useful projects that I can duplicate.

BTW, I found this website projectsinmetal.com with lots of free plans etc but they're fairly advanced.

 

[jhn9840]

http://bbs.homeshopmachinist.net/index.php

http://www.practicalmachinist.com/vb/index.php

http://groups.yahoo.com/group/7x10minilathe/

I don't own a mill or lathe but wish that I did. Good luck with yours.

jhn9840
John

 

[Uncle Buck]

Russell, head to the scrap yard, or look in the yellow pages under steel and do your shopping there for material.

 

[Jack Olsen]

Russell, if you could use a small practice project, I've got three die wheels for a rolling bender I need cut out from 1/2" to 1". I'll even throw in a set of HF bits for your trouble.

 

[stioc]

John, thanks for the links, I'll check them out.

UB, there aren't really any scrap yards around me so I'll have to do some digging. There are plenty of machine shops though. In fact, I found out that there's a machine shop at my work (Manufacturing) that recently threw away a bunch of scrap metal

Jack, I'd love to help but I'd also hate to screw up your expensive die wheels

Nevertheless, what's the length and diameter of the die wheels. By "cut-out" I'm assuming you need the length shortened (not the diameter)? Also what material are they? I'm finding out that HF bits are not the sharpest bits out there for anything other than PVC pipes

I'm in South OC and you're welcome to come make some chips in my garage if you want.

 

[ahaidet]

I always buy my metal at a local salvage. The prices are usually less than half of what McMaster/Lowes/HD would charge and the metal is good stuff. Hard to request a specific alloy as they do not always know but for most stuff "steel" is good enough...

 

[A_Pmech]

Be careful of the scrap yard.

There's a lot of tough "mystery metal" in there.



I'd start with a few feet of 1" Aluminum and work from there. Aluminum is very free-machining. As such, it is forgiving of poor tool grind and speed/feed errors.

Alloys 2011 and 2024 are a joy to work with using sharp high speed steel tooling.

 

[murph64]

http://bbs.homeshopmachinist.net/index.php

http://www.practicalmachinist.com/vb/index.php

http://groups.yahoo.com/group/7x10minilathe/

I don't own a mill or lathe but wish that I did. Good luck with yours.

jhn9840
John

There's a good bunch on HSM. PM is a great place to lurk, but be careful of posting there. Don Thomas (Milacron) who owns it, is NOT TOLERANT AT ALL of postings on HF/Grizzly type machines. He will rag on you and lock the thread.


Andy

 

[stioc]

I just wanted to take a moment and say a huge thank you to Jeff (79pacecar) who read this thread and then offered me his lathe tool bits from when he used to be a machinist True to his word the tools bits arrived today, how cool is that?

Jeff if you read this thank you, if not, a PM is on its way too

 

[A_Pmech]

Cool beans!

That should keep you going for a while.