Are smaller lathe cutting tools available?

[ScanmanDan]

As a newbie lathe owner ( Baby Seig C-0). I'm having a little trouble turning very small parts. I have been using the 8mm shanked cutting tools that came with the lathe and while they cut very well they aren't the easiest to use to turn really small parts. I don't have a bench grinder or the skill to grind my own from scratch so I was wondering if there are some smaller cutting tools commercially available. Or is it just a matter of my lack of skill with the lathe?

Are there any good books that describe how to use a lathe for the hobbyist?

Thank you all for all the great ideas and information on this forum as it was a great help to me in the purchase of my lathe and got me started turning.

Dan

[chola]

G'day Scanman Dan,

You won't really find cutting tools much smaller than 8mm, I think I have seen 6mm in the past, but not very often.

If you need a really thin section to machine say, a groove into a piece of rod, this is a method I have used with great results....

Get on ebay and buy a selection of HSS blanks (4mm square). Then if you don't have a bench grinder or even a Dremel type rotary tool, go and buy a cheap set of grinding / cutting wheels and shanks from a hardware store, should be less than about $20 (get the ones designed for the Dremel type tool).

Attach a 'green' grinding wheel to one of the shanks and secure it in the chuck of the lathe, let it hang out a bit. Then secure the tool blank in the tool post at 90 degrees to the wheel. Start the lathe and slowly move the cross-slide past the grinding wheel (left and right), keep moving it in and repeating until you have ground a suitable angle on the front of the tool (there are numerous references to this on the web). To get a very thin section (say .5mm wide), move the cross-slide to the edge of the wheel and slowly crank it in so the wheel is grinding lengthways down the HSS blank. You don't need to go down far is you only need to make shallow cuts, keep repeating this process until you have ground enough away to get the desired sized tool.

Essentially this is using your lathe as a bench grinder, but by mounting the HSS blank in the tool post it give you much greater control of the cuts / grinding that is being done.

This is not an ideal setup, but has produced pretty good results for me when I have needed to machine very small grooves in alloy.

Don't worry about lack of skill, we all had to start somewhere, just keep having a go and you will work out how to overcome little hurdles like this.

If you don't have already, get yourself a proper parting off blade and holder, this will immediately allow you to make thin grooves in metal as they generally range in size from 1.5 to 2mm wide. You may not want the expense of a quick change tool post at this stage, but that would also be worth considering later.

You also need to spend some time planning how to cut the piece to minimise waste, and to make the operation easier.

Let me know if you need more info, happy to help.

Good luck.

Colin

[ScanmanDan]

Thanks ever so much Colin.

I would never have thought of using the lathe itself to grind cutting tools. Great idea but I shudder to think what a commotion it will make in my shop which is in a small back bedroom of the house. Maybe I'll wait until SWMBO is out of the house before I give it a try. I take it from your description that I should go very slowly and not over tax the motor of the lathe. Will I need to worry about the temper of the cutting tool? Or should that not be a problem with cutting aluminium and or brass with a HSS tool. I'm itching to give this a try now, Thanks!

I can already see the advantages of a quick change tool post as swapping out shims for the different cutting tools is becoming a bit of a chore. I also have one of those thin parting off tools on back order and I think it will do a much better job than the broad (3mm) one that comes in the pack of cutting tools.

Thanks for the encouraging words they mean a lot to me as I am slowly learning as I go along. I've never had any training on a lathe and the company that sold me mine doesn't have anything in the way of books/DVD's for metal lathes as they specialize in large wood turning machines. Are there any good books/DVD's relevant to the hobbyist on the market?

I must confess to getting a lot of pleasure out of working things out for myself but there are a lot of times that I feel I'm reinventing the wheel so to speak. I'm most concerned about the safe use of this little lathe. I waited 30 years to afford one and I sure don't want to blow it up doing anything foolish.

Most of all I'm having a great time with my little machine and wish I'd saved up for one years ago.

Thanks again,
Dan

[chola]

Hi dan,

No worries. It's pretty quiet doing this grinding procedure, just go slowly and smoothly and you'll be right.

Just get any standard HSS tool blank and it will work fine with cutting alloy, actually HSS gives a very nice finish on alloy and brass.

The parting tool that comes in the set (3mm), puts a lot of pressure on the lathe when parting, as well as a lot of wasted material.

I don't know of any books on the subject (most seem to be very pricey), really just get in and have a go, you will soon learn what works and what does'nt... if in doubt ask the question here, or send me a PM and I'll lend a hand where I can.

Another suggestion is to get on you-tube and look under lathes, cnc lathes and the like, and see the directions and methods these machines use to make cuts and perform various operations like drilling. This will give you a good idea on how to proceed.

Safety is something of great importance, so always wear goggles / safety glasses when machining, never file a part while it is turning in the lathe either, if you must do this, always use a file with a proper handle on it, the steel 'tang' of a metal file can do some serious damage if it catches and gets forced back into the palm of your hand!

Make sure you also have a few spare fuses handy, trust me, you will blow some from time to time.

Good luck with it, and let us know how you get on.

COlin

[Murray Kish]

http://www.ares-server.com/Ares/Ares...oduct&ID=82761

[ScanmanDan]

Colin-- Thanks for the further advise. Especially about safety, very appropriate as I'm not the best with power tools. I've been using googles but I'm thinking of going to using a full face shield as I like to wear close up glasses to get a better view and I not too keen on getting swarf in the face.

I'm still awaiting my overseas order for thin parting tools and I haven't managed to get any small tool blanks to try and grind my own. Though I have obtained the green type Dremel wheel. I did notice that Dremel rates these for polishing hard materials and the orange ones are rated to grind hard materials. I'm going with your recommendations and see how I go.

Murray-- Thanks for the link to the 3mm cutting tools. Has anyone any experience with using these? I notice that MicroMark have three different tool holders for these cutting tools. Left, right and straight. Any real difference in them apart from the obvious? I've been turning the tool post to adjust the angle of the tool to the work. Is this bad practice?

I appreciate the time you guys take to help out us newbies. Thanks.

Dan

[Murray Kish]

I noticed those 3mm tool holders as well. I thought the same thing... why not just turn the tool post? You'll still need some sort of adapter to fit the 3mm tool into the larger toolpost, but being machinists, my guess is that we could rig some sort of adapter up pretty easily?

Murray

[MPWR]

Welcome, Dan! Glad to hear you're finding the forum to be useful. The more you ask, the more help we can be.

Using a lathe as a precision grinder is a clever idea but for one thing- you wind up with alot of grit on your lathe, which can quickly and completely destroy it. The abrasive dust worn from the grinding wheel can get into the slides and leadscrews, and that's bad, bad news. If you ever do this kind of grinding on your lathe, cover everything (everything!) with aluminum foil to protect your components, and be very careful unwrapping afterwards.

The clever machinist makes a precision toolpost for grinding lathe bits on his bench grinder. Design it to move in X and Y with leadscrews (1/4 x 20 are the same screws on my tooling), and to hold a bit at any angle relative to the grinder wheel that you need. When the parts wear out, remake them.

I've been turning the tool post to adjust the angle of the tool to the work. Is this bad practice?

No problem at all.

And if you don't have a tool post that will hold a bit the way you need it, make one that will!

[MPWR]

Those are great!



May have to get myself a set....

[ScanmanDan]

Just a little update.

Received a small package from Micro-Mark on Friday which contaned a micro cutoff holder and some extra blades. It was my first order from them and their prices seems quite good and the overseas shipping wasn't too expensive. Now that I know they are okay to deal with I have a shortish list of goodies to get from them .

I've had a little play with the cutoff blades this morning and I have to say they work great. The one that came with the holder worked out to be 1.3 mm wide and cut a nice slot into the aluminium test bar. I only cut in a few millimeters but all seemed well with only a tiny bit of chatter, not the howling I had experienced before. The tool also left nice square shoulders and would work especially well to tidy up the angled shoulders I sometimes end up with when using the angled cutters. (I'm probably using the wrong cutters for my turnings and leaving these angled shoulders.)

I did try and thin down one of the spare blades to 0.5 mm using the green Dremel grinding disc as suggested by Colin. Once I got the blade all squared up in the holder and alined the toolpost I took tiny little cuts with the grinding disc until I got the blade thinned to 0.5 mm. I only cut into the blade a few millimeters to notch the cutting edge with the idea of using these blade to make some thin slits or fins in a turned piece. All worked well and used a diamond lap to polish up the finished edges. The modified blade will now cut 0.5 millimeter slots to about 2.5 mm deep. Plenty for what I want it to do. In grinding this blade I do see MPWR's point about getting grit everywhere. I don't think I'd try shaping a 3mm HSS blank this way with out a bigger lathe and/or covering the lathe bed to keep out the grit. But for dressing and minor shaping like this the method worked well enough and gave me quite good results.

I've got to say again a big thanks to you guys for giving me the confidence to try this stuff. As a newbie this stuff is all new and quite scary. I can see now that with a little guidance and care plus a watchful eye towards safety even a fumble futz like me can get expectable results. It's a blast turning bar stock into something useful. I'm going to purchase those micro cutters and a straight holder from Micro-Mark this afternoon and I've found a place that sells replacement fixed tool posts for the Baby C-0 lathe. I'm thinking of getting a few spares so that I can set each one up with a tool set to the correct center height and swap them out, kinda like a poor mans quick change tool post. These lathes cost more in tooling than in the original purchase but gee they are fun bits of gear.

Hmmm, that baby micro mill looks pretty interesting...


Thanks again for all your help and support. Comments and guidance always appreciated.

Dan

[ScanmanDan]

Just a little update.

I received my 3mm cutting tools set and straight tool holder. I haven't the time to play with it until the weekend but I thought a quick picture might help others who are thinking of getting a set. The red tool in the picture is my normal 8mm sized cutting tool. I very much like this set but the proof will be once I get to cut some metal.

I can already see that it will be heaps easier to get into tight spaces with these new tools. It is a bit strange though that I'm spending as much on cutting tools and holding vises as I spent on my lathe in the first place. Still, it is all fun .



I hope this helps.

Dan