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Matthew
04-04-2019, 11:27 PM
Can any one here give me pointers on a Thompson model B 6"x18" surface grinder? Quirks of the brand, general troubles, known points of concern with them, etc. The machine itself has been well taken care of by the current owner.

I've got a small knife shop / smithy & its picked up to the point that I've not got the time to hand file a blade flat anymore. Good problem I suppose.

I've used plenty of surface grinders before, but they've all been 40 to 50 years newer & far out of my budget. So old school it is. Also picked up a Roku-Roku drill press.

Any advice is greatly appreciated. Thank you.

rickyb
04-05-2019, 09:05 PM
Can any one here give me pointers on a Thompson model B 6"x18" surface grinder? Quirks of the brand, general troubles, known points of concern with them, etc. The machine itself has been well taken care of by the current owner.

I've got a small knife shop / smithy & its picked up to the point that I've not got the time to hand file a blade flat anymore. Good problem I suppose.

I've used plenty of surface grinders before, but they've all been 40 to 50 years newer & far out of my budget. So old school it is. Also picked up a Roku-Roku drill press.

Any advice is greatly appreciated. Thank you.

I have a TML but not sure of the model #. It is a nice machine as the ways are covered nicely. Ways are soft. No oil cups on the X axis which I need to add.

The only quirk of the machine is on the X axis. Ways are too short and nothing holds the table down except gravity. When I was grinding my 13" wide mag chuck the table would lift as I got to the edge of the chuck. There is so much overhang on the opposite side that the table lifts off of the ways. You will need to hold it down to prevent the wheel from digging a hole in the chuck. One inch from the edge is no problem. It is that last 1/2". My chuck is a heavy electric LW Chuck 6x13x3". Lift may not be a problem with a longer flatter manual chuck.

Mine grinder was well taken care of also. Yah, right. 0.020" wear on X and Y ways. About 0.004 on the Z. Totally un-useable with out the chuck. Had to scrape in the entire machine and then scrape and grind 0.020" off of the chuck. Since I was doing a deep dive I changed out all of the bearings.

You say you don't have time to file knives flat. I don't think you will save much time using a surface grinder. I'm thinking it may take longer. It will however look prettier.

Matthew
04-06-2019, 11:18 AM
You say you don't have time to file knives flat. I don't think you will save much time using a surface grinder. I'm thinking it may take longer. It will however look prettier.

Pretty is the money maker in my business unfortunately. I'd much rather be at my anvil swinging a hammer forge welding a billet than doing surface prep by hand.

The main difference between this machine & everything else I've used, is the cross feed head vs a cross feed table. So that should be interesting.

rickyb
04-06-2019, 12:44 PM
Pretty is the money maker in my business unfortunately. I'd much rather be at my anvil swinging a hammer forge welding a billet than doing surface prep by hand.

The main difference between this machine & everything else I've used, is the cross feed head vs a cross feed table. So that should be interesting.

You will need to experiment with wheel to optimize material removal against burning and warping. Soft wheel with open grit would be a good start.