Author Topic: Tool Post Grinder (Read 186564 times)

sbwhart · « **Reply #50 on:** October 11, 2009, 01:45:41 AM »

Hi Chaps

Johns got it spot on correct

By mounting the Router the other way round I can drive the spindle clockwise, this will also give me a better view of the action.

I did think of using the router direct but it had two things going against it:- The lower speed of 11800 rpm is far too high for external grinding and may burst the wheel so I've got to gear it down:- I stripped the motor down and its bearing just wont be up to the job of grinding they are located in a plastic housing.

Cheers

Stew

NickG · « **Reply #51 on:** October 12, 2009, 07:51:06 AM »

Stew,

does the chuck on your lathe screw on and off or does it bolt directly to the spindle? I know some of the chester ones do.

Nick

sbwhart · « **Reply #52 on:** October 12, 2009, 10:03:34 AM »

Nick

The chuck is held on with three M8 cap screws so no fear of it unscrewing.

Stew

bogstandard · « **Reply #53 on:** October 12, 2009, 10:47:41 AM »

What you need to remember, when toolpost grinding, the grinder is going full tilt, but you only have the job rotating fairly slowly, and the grinding pressure on the job is miniscule, so there is very little chance of your chuck coming undone if run in reverse.

You are only removing very small amounts, maybe only 0.001" (0.02mm) or even less at a time. Some people seem to think it is a quick way to remove metal, far from it.

Bogs

NickG · « **Reply #54 on:** October 12, 2009, 11:25:58 AM »

Yeah, the only time I used a surface grinder I seem to remember taking cuts of 0.0001" ! I made finished off a 4 way tool post I made for a small lathe on it, it made even my machining look good!

Nick

sbwhart · « **Reply #55 on:** October 15, 2009, 12:14:45 PM »

I bet you thought I'd given up on this, you should know me better than that.

Any way wasn't too happy with the base plate tried to repoistion the motor on it and made a right cock up of it:- it now had more holes than a piece of Swiss cheese.

So re made it and positioned the rotar so that it drove the spindle clock wise.

Now to sort out mounting the wheels.

I made some blank quils with a female fixing.

To mount the quils the shaft required turning down for a male fixing

To do this I decided to try my ER32 collets on the lathe, I had to turn and drill the adaptor plate so that it would fit the lathe and my RT, for the ER32 mount instead of fitting it on a spigot I just fixed it to a flat face with the three fixing screws, I just nipped up the three screws clock the bore up dead true tighten the screws clocked the bore corrected the error tightend the screws some more so that it was realy tight clock the bore again spot on.

Took the shaft out of the spindle and mounted it in the ER32 clocked it up it was running dead true

Gently turned it down so that the concentricity wouldn't be spoilt.

I can mount external wheels on this.

Then mounted one of the blank quils to it and turned this down to a Dremel mounting.

Her it is with the chuck and point in place.

Thats all for now next job put some spanner flats on the shafts, sort out the dead man switch and thats just about it.

Stew

John Hill · « **Reply #56 on:** October 15, 2009, 02:15:33 PM »

Stew, have you run your router motor yet? I have great difficulty in finding a suitable belt for the speeds involved. A 6mm urethane round belt just expands into a big elliptical shape then flies across the room! The most effective so far has been half a dozen individual strands of cotton fishing line.

sbwhart · « **Reply #57 on:** October 15, 2009, 03:55:00 PM »

Hi John

Yes I've ran the router low and high speeds the radthane belt copes OK, it does throw a curve up on the slack side but so far its been OK, tried loading the system by getting hold of the shaft still ok until my hand starts to burn then I let go. Only fun I had was when I ran it with the bearing too tight I didn't noticed it had picked up on the pully, it burnt the belt through in less than a second.

Cheers

Stew

CrewCab · « **Reply #58 on:** October 15, 2009, 06:02:05 PM »

Nice going Stew

CC

sbwhart · « **Reply #59 on:** October 18, 2009, 06:03:21 AM »

OK first trial run, I saw some belts at the midland show for £2 each for the enco lathe just the right size for the grinder and a bit harder rubber so they don't balloon out the same as the redthane belts.

Rigged up a dimond for dressing the wheel (thanks John)

For want of something to grind I decided to give my centre punches a clean up.

And this is the result:- real nice finish and good sharp point.

Quite pleased on how it went

I think I need another way of mounting the internal points other than the dremel collets system I've got.

But that job can wait until its required.

Cheers

Stew

Darren · « **Reply #60 on:** October 18, 2009, 06:12:40 AM »

Very nice Stew,

Very inspiring

Darren · « **Reply #61 on:** October 18, 2009, 06:39:56 AM »

Stew,

You can't be that far off regrinding your endmills, add another angle, index the lathe chuck ?

sbwhart · « **Reply #62 on:** October 18, 2009, 07:26:27 AM »

Darren

Thats my next project, I think I'll call it the "Potty Tool and Cutter Grinder"

I wont be using the lathe, and I don't think I'll be using the tool post grinder, I'll be using something far more simple. I will use:- a Table, a Verticle slide, a bench grinder, a Stevenson Indexer, all put together using the sony walkman school of design principles.

Stew

bogstandard · « **Reply #63 on:** October 18, 2009, 07:35:55 AM »

Nice one Stew, that is one of this clutch working, are any more members having any luck.

With regards to the Dremel chuck, I thought I had advised you to use a pin chuck. A normal chuck will try to vibrate itself apart and come loose very easily, and also it would soon lose it's accuracy because it is a nice haven for grinding dust to settle inside it.

But well done on your success.

John

sbwhart · « **Reply #64 on:** October 18, 2009, 07:52:03 AM »

Hi John

You did indeed advice a pin chuck, but I stubidly though you ment the dremel pin chuck, having fitted one I soon realised I got it wrong I'll have to have a look at what you mean by pin chuck.

Thanks

Stew

Darren · « **Reply #65 on:** October 18, 2009, 07:59:49 AM »

No gears or key on a pin chuck Stew, just a threaded nut like a collet holder.

The rotation, if in the right direction, can only cause it to tighten.

Edit, looks like what you have, so I'm lost now too

Maybe takes a small collet?

bogstandard · « **Reply #66 on:** October 18, 2009, 08:53:12 AM »

What Stew has is a mini chuck, slidy bits wiv springs inside.

This is a pin chuck

http://www.axminster.co.uk/product.asp?sessionID=QOL&pf_id=33442&name=pin+chuck&user_search=1&sfile=1&jump=0

But unfortunately it doesn't go up to the size required, but they are very accurately made.

These are pin vices

http://www.axminster.co.uk/sessionID/QOL/product-Axminster-Pin-Vice-Set-33440.htm

Not as accurately made as a pin chuck, but do go up to the size required. With a little bit of work, they can be made accurate enough to do the job.

Before doing any of the below, you will have made one of your adapters to fit the grinder and drilled a nice concentric hole in the end, say 1/4".

Find the pin vice you want, say to fit a 1/8" mounted point.

Get rid of most of the handle and leave about 1/2" under the thread.

Mount a short length of 1/8" silver steel into your lathe mounted ER collet chuck.

Then grab the stub of SS sticking out of the chuck with what is left of the pin vice.

Using you newly made toolpost grinder, gently grind back the stubby area under the threads until it is nice and concentric and is a nice snug fit in the hole in the end of the adapter you have made.

Stick the two together with loctite.

That is basically how the one on my grinder is.

Bogs

sbwhart · « **Reply #67 on:** October 18, 2009, 09:04:08 AM »

Ha Haaaa the penny has dropped

I can remember you showing me this but it was all too much for me to take in at the time.

Thats a real neat idea John, When I got the mini chuck it just didn't seem right, and when I fited it I knew it wasn't up to the job.

I place an order for some pin chucks.

Thanks John

Stew

John Hill · « **Reply #68 on:** October 18, 2009, 01:34:41 PM »

Excellent work Stew! Meanwhile I have a little way to go with mine.

sbwhart · « **Reply #69 on:** October 18, 2009, 02:23:31 PM »

Thanks Chaps

I hope to make good use of it in future projects, they realy are a usfull bit of kit that helps you to take on jobs that you would have strugled with.

Cheers

Stew

sbwhart · « **Reply #70 on:** October 20, 2009, 07:35:14 AM »

Wow what quick delivery

Ordered a set of pin chucks from Axminster yesterday lunch time, came in from the shop today to have some lunch and look what was on the door mat

Stew

sbwhart · « **Reply #71 on:** October 21, 2009, 07:49:52 AM »

Ok after the desaster with the Dremel chuck, had a go making a grinding point chuck using a pin chuck as suggested by John.

Make another quil this time I drilled it out 9mm

Then get rid of the parts of the pin chuck not wanted.

Then grip a bit of 1/8" silver steel good and tight with the pin chuck, then gripping the silver steel with an ER collet gently turn the end down to 9mm + 0.20mm, then gently flash down to size with the tool post grinder so that it fits nicly in the quill.

Then supper glue the pin holder in the quill and thats it job done, the points run dead true.

Well pleased with the result 1000 times better than dremil chuck.

Cheers

Stew

bogstandard · « **Reply #72 on:** October 21, 2009, 08:16:36 AM »

"Super glue", he says in a high pitched voice.

I told you to use hi strength loctite.

I told you it should work better than that grotty chuck.

BTW. This message is now being sent with my all singing, all dancing, new desktop computer.

From a bare bones box, to being on the net, 1.5 hours.

Bogs

sbwhart · « **Reply #73 on:** October 21, 2009, 09:02:37 AM »

When I was gluing it I thought Supper glue or loctite one of them is brittle

which one did John say:- eene, meeni, mine, mo and I got the wrong one

.

Happy new computer John

Stew

NickG · « **Reply #74 on:** October 21, 2009, 10:56:08 AM »

That's great Stew, you'll be able to do all sorts of stuff with that.

Nick

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Author Topic: Tool Post Grinder (Read 186564 times)

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