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loose nut
01-25-2008, 06:43 PM
Little Machine Shop has two tool post grinders for sale for small lathes, has anyone had any experience with them, will they produce good work? For hobby work I can't justify the cost of an industrial model like a Dumore. Any feed back would be helpful.


http://littlemachineshop.com/products/product_view.php?ProductID=1275&category=

http://littlemachineshop.com/products/product_view.php?ProductID=1275&category=

garyphansen
01-25-2008, 08:35 PM
The both look like the same one to me! Gary P. Hansen

oldtiffie
01-25-2008, 08:49 PM
The both look like the same one to me! Gary P. Hansen

Nope.

The first has an adjustable speed and the second is fixed speed.

Herm Williams
01-25-2008, 09:26 PM
I have one at home and there is a couple where I work. In the last five years I have used it one time. When you need one it will pay for itself.
re

oldtiffie
01-25-2008, 09:32 PM
Little Machine Shop has two tool post grinders for sale for small lathes, has anyone had any experience with them, will they produce good work? For hobby work I can't justify the cost of an industrial model like a Dumore. Any feed back would be helpful.


http://littlemachineshop.com/products/product_view.php?ProductID=1275&category=

http://littlemachineshop.com/products/product_view.php?ProductID=1275&category=

Hi Loosenut.

Not a bad grinder at all for the money really.

Get the variable speed one - the first/dearest one.

I have one.

You will need an adaptor for the grinder to fit on your cross-slide - the following drawing supplied by LMS might help.
http://littlemachineshop.com/Projects/Drawings/ToolpostGrinderMountAssy.pdf

As usual with most of my Chinese stuff, I had to made a few minor alterations.

The main problem was the cheek-plates for the grinding wheel.

I replaced them as the inner one did not locate on the spindle as well as I'd have liked and the outer one was only a loose fit in the grinding wheel bore and did not locate on the inner plate.

The result was a lot of "out of balance" problems.

I made new cheek plates. The inner one (10 deg included angle taper) was pressed onto the spindle - the spindle was held against a centre in my lathe head-stock and the cheek plate was pressed on with the quill in my tail-stock to keep everything true and square.

Once the new cheek plates were fitter, the grinder performed marvelously. I was very pleasantly surprised to see just how smooth it was -especially so as there is no means of balancing the wheel and cheek-plate assembly.

The spindle speed adjustment is very good and it holds up under load. It is also reversible.

The small 3-jaw chuck (supplied) can be used for small cutter end-milling or drilling. The chuck ran very true.

The grinder can foul the tail-stock quill but with care is OK.

For $US200 it does a very passable job.

The taper that I put on the inner cheek-plate was good enough to "wring" on as good as a MT adaptor.

There is a good "Emergency Off" switch as well that works well.

I pulled mine apart - other than the spindle bearings - just to see how it was made and put together. The multi-vee flexible belt drive is excellent. Getting the belt tension right is OK - not too easy, but as it doesn't have to be done all that often is OK.

I would make a point of keeping several of each grade of grinding wheels and a driving belt as spares.

It won't act as internal grinder if the bore to be ground is much under about 3".

I bought the top of the line "Roxxon" grinder (and wheels etc) from LMS as well for internal grinding.

http://littlemachineshop.com/products/product_view.php?ProductID=2891&category=

They also have a tool-post adaptor for the "Roxxon" but it is easily made but its cheap as well.
http://littlemachineshop.com/products/product_view.php?ProductID=2935&category=

That "Roxxon" grinder is a really class machine. It is not cheap at all - but IMO was well worth the price. The "Roxxon" is accurate, has plenty of speed adjustment and it holds its revs under load. The collets supplied are very good too - but being small are easily lost - so take care. It is the best die-grinder I have ever had.

IIRC, Paul Allicoterie had several posts regarding using a spare spindle that he had to make either or both of the TPG external/internal grinder/s. They were very well done indeed. Perhaps you might like to PM Paul A for assistance/advice - he knows his stuff. AIR, Paul's spindle was something like this:
http://littlemachineshop.com/products/product_view.php?ProductID=2892&category=

He did it very well and lots cheaper then the "Roxxon". I'd guess that spindle or similar might do for both internal and external grinding if you make a spindle adaptor/extension for internal grinding.

All of this pre-supposes that only light grinding loads are going to be applied.

I hope this helps.

Optics Curmudgeon
01-25-2008, 09:39 PM
They'd better look the same, both links are the same, exactly.

Joe

loose nut
01-25-2008, 10:18 PM
Oldtiffie, that was exactly the info I was looking for, Thanks.