Shop Made Tools

[Hopefuldave]

Do you mean tungsten carbide?

Tungsten electrodes for TIG welding torch? I use much the same (diamond disc on the end of a small grinder, spin the electrode with cordless drill) for mine...

Dave H. (the other one)

[RMinMN]

No. The diamond wheel. I understand they can be easily ruined by grinding something other than carbide????

Grinding steel hard on a diamond wheel will ruin the diamond wheel as the hot ( like red hot) steel will absorb the carbon (diamond) into it.

[MattiJ]

Thanks Matti, I'm going to look that up and consider it as an option to a diamond side wheel for my tool grinder.

Considering the price they are excellent option for sharpening occasional lathe tool or carbide scraper. 3000 grit gives you mirror finish and razor sharp cutting edge.
I use them also to touch up HSS tools.

[Tungsten dipper]

Do you mean tungsten carbide?

Tungsten for TIG welding.

[DennisCA]

I honed one of my HSS tools for my wood lathe on the 3k disc and I've never had a tool cut that good.... Just a few seconds touch up work really.

[Dave C]

Is it a flexible disk?

[hornluv]

It's not much, but I just finished some little magnet handles so I can hold prints near my machines. The magnets are rare earth magnets from Harbor Freight, SKU# 67488. They're really cheap, less than $3 for ten of them. Then I just used some aluminum round I had sitting around and epoxied the magnets in. It took me longer to make a form tool for the ball end than it did to make six handles. Here's a video showing how I did it: https://youtu.be/JI1yYuvh_Tk

[DennisCA]

Is it a flexible disk?

It's steel, it flexes somewhat under pressure but not a lot. I've thought of making a backing plate.

[BCRider]

Hey wbc, if you're still reading in on this I just want to add my own kudos to your amazing work. That's some serious dedication to shop tooling and done to very high standards.


I'm getting stoked on the idea of lapidary discs. I'm finding full coverage single sided face cutting "lapping" discs in grits from 240 to 3000 at around $20 each even in my lowly Canukistan Copeks Currency.

I also like the idea of a wet operation for this work. Not only to increase the life of the diamonds but also to hopefully reduce the amount of carbide dust floating in the air afterwards. So the disc will be shrouded by a recurved peripheral mist recovery guard and drain. To keep it simple I'll feed water onto the disc via an overhead jug and small line that delivers the water to the center of the disc just outside the flange nut and let the centrifugal force spin the water across the surface.

I'm thinking of an integrated setup for a backing disc that has a center pilot to center the disc and a thin ring nut with two holes that uses a wrench much like angle grinders use. This would make for rapid and easy grit changes.

Thanks to the spray collection shroud and a flinger groove I'll include I should be able to keep any water even after shut off from migrating along the motor shaft and going into the bearings. So I should be able to use a regular grinder. Or perhaps I'll buy a tile saw and use the motor from that. I'll have to have a look at my own tile saw to see what the shaft size is....

I'm getting stars in my eyes from the CBN grinding wheels that showed up in the "you may also like" sidebar while looking at the discs. I'd like one for doing HSS and my more pedestrian carbon steel tools. Between this new direction and wanting a nice belt grinder I may end up totally "stoneless" in the next year or so for all my grinding.

[Dave C]

It's steel, it flexes somewhat under pressure but not a lot. I've thought of making a backing plate.

Ok, thanks. I was looking on eBay and there are a bunch of different types. A backing plate sounds like a good idea.

[wbc]

BCRider: The kudos -Gratzie.

Re: the recently mentioned diamond lapidary discs and diamond wheels...I use a wet sponge on the end of discarded
lamp flex-arms to keep wheels damp on a grinding jig made up of junk which I use to sharpen drills and the ends of
endmills, both carbide and HSS. No ill iron-diamond wear on wheels that I have found at 1800rpm/ 6" on a 1950's
Teletype motor-bolted-to-a-chunk-of-iron rig. Cheapo Aliexpress lapidary discs seem fine, but then I don't know better.

Also use a wet-sponge-arm on vertical and horizontal 70-200rpm lapidary disc grinders (partial view of horizontal platen
in right background.) No Glendo Accu-finish grinder contender, but those cost $1000 more than $6 and some assembled junk.

[BCRider]

So I'm over thinking things again.

I'll start with the backing disc and see how it goes for the water wetting.

[ATW]

I wanted some physical stops on the rotary table too stop me getting too carried away cutting some radii, came up with these little clamps to sit on the edge of the table between the lip the lock clamps act on and the table top:

The toes at the bottom are slightly angled so they rest tangentially to the edge of the table.

Was thinking of using the lock clamps (reversed) as something the stops could act against, but with only a single bot to hold them they seems not very substantial, so made a more substantial bracket from a bit of angle:


All together:

You can't quite see in the last photo, the stops are just tall enough to allow a piece of shim stop to be fitted to prevent the set screws marking the table top.

The one possible drawback I can see, is what happens when you want the stop at/near one of the T-slots - oh well that will be a project for another day, maybe need to make some wider stops for those occasions.

Andy

[Dr. Rob]

Dude, i have wanted stops on the rotab for ages. Just never got around to it. Thanks for the inspiration.

[rcaffin]

When grinding with either diamond or CBN, you should (emphatically) NOT be applying all that much force. Let the abrasive do the work. Otherwise you will trash the disk.

Yes, you should use diamond WET. I cover the whole tool when grinding basalt (it's hard, Mohr 8-9) with diamond. Good tool life when I do that.



When drilling ruby balls (Mohr 9) I immersed the whole lot too.

The white ring is ruby powder from the drilling. Had to be very careful with the ruby: delicate spring-loading of the ball against the drill.

Cheers
Roger