Mounted Points On A Lathe

[sbx]

Hello,

So, I've been pondering using my mini Air Die grinder in my AXA boring holder as a mini tool post grinder (South Bend 9A). I've seen some use this with success. But, am a little concerned with grinding dust. Even if I use a vitrified type stone while adding way protection, I am a little clueless on the optimal shapes to use for various purposes. I am guessing a selection of grits and shapes would be worth having. Here I am just looking for some of the most common shapes and sizes that would fit this application.

So, I thought it would be a good discussion topic. One other thought that came to mind was to see if there were any CBN type mounted points, or if anyone has used them to any level of success. The idea would be less grit to deal with.

What about Cratex, or buffing wheels? Other cool things I haven't even thought of yet?

So, with a 1/8" Shank in mind, what comes to mind for what uses?

Me, I am just trying to expand the usefulness of my lathe, and potentially add some nicer finishes and ground angles, points, or flats to my projects. Thats what I had in mind anyway.

Thoughts?

 

[ch2co]

Abrasives, no matter in what form, are abrasive. I have a full size electric die grinder that I made a tool post holder for and it works very well, with cut off wheels or grinding stones, sanding discs, etc. I always cover as much of the lathes workings as possible with shop cloths. After finishing, I carefully remove the shop cloths and wipe everything down with clean cloths and finally oiled cloth. An air driven grinder might compound the dust/grit problem with its air flow?

CHuck the grumpy old guy

 

[Big Bore Builder]

As you have a lathe, one of your projects should be making a tool post grinder. Two shown below, a conventional grinder and a small belt grinder. Both made from finds in the scrap boxes.



About that dust problem: Suck it up!

Grinder is running in reverse, throws the column of grinding dust up and the shop vac takes care of it.



Another use for the belt grinder, this time using the contact wheel instead of the "slack belt". In fact, this type of tool post grinder is called a "slack belt grinder".





Grinding a center:

 

[David VanNorman]

Darn nice grinders. Did you use angular contact bearings or regular? I've been wanting to build a grinder but I've wondered about bearings.

 

[DSaul]

I can't be of much help on tool bits, but for a grinder, I bought a Dremel mount from Alisam engineering that allows you to mount a dremel to a quick change tool post. You can't beat it for $19.99 http://alisam.com/page/14g9f/Metalworking.html Sure, its a simple project to make one, but I didn't have a mill at the time.

 

[Big Bore Builder]

Darn nice grinders. Did you use angular contact bearings or regular? I've been wanting to build a grinder but I've wondered about bearings.

Angular contact.

Both grinder projects were born out of the junk boxes with nothing purchased. I have collet type chucks for the tool post grinder allowing using both 1/4" and 1/8" shank grinding points.

Motor on the tool post grinder is a 1/2" drill motor, universal AC/DC. Up to 5000 rpm.

Motor on the belt grinder is a DC from a salvaged blue print machine.

Both are driven using a variable DC power supply, an old Minark that I rescued from a dumpster. Only thing wrong with it was a blown fuse. In addition to controllable output DC it has forward/reverse. It is mounted on the lathe stand, the grinders have QD plugs to fit the power supply.

 

[rpmMan]

can you tell us more about the custom steady rest ?
thanks

rich

 

[rgray]

I've been wanting to build a grinder but I've wondered about bearings.

Watch Ebay for a dumore tool post grinder spindle. The entire tool post grinders on ebay sell for real high out of reach prices for me, but the spindles are usually in the $100.00 range.
Once you have a spindle the job of building a TPG is much easier.

 

[Big Bore Builder]

can you tell us more about the custom steady rest ?
thanks

rich

Made it 25 or so years ago for rifle barrel work.



Works like a 4 jaw chuck. The axis of the steady spindle is aligned with the axis of the lathe.






Made from an old babbitt bearing pillow block. I bored out the babbitt and cast iron housing to fit large diameter angular contact ball bearings, then turned a hollow spindle fitted with SKF bearing lock nut.





Ten times easier to use than one of these. And it does not marr the barrel!



I have used it for truing M700 actions, sorry, no photos.

 

[rpmMan]

big bore:
thanks... very nice work