Quick Grinding Graver Blanks

[jimzim75]

Hi All,
I bought some one eighth carbide rod a while back to see if I could make
a stiffer version of the John B gravers. I was at a loss as to how to index it.
JC had said that you might as well just grind a flat on the rod.
I was looking at the post with an idea about using a drill press for the
grinding wheel and everything clicked into place.

If you could run the drill press at a higher speed, it wouldn't take as long to
grind blanks. I normally use a GRS graver hones and dual angle fixture.
Having had two shops, I actually have a double set up. One set of diamond discs
was sitting idle. So I found a carriage bolt the fit exactly in the center hole of
diamond disc and with a couple of nuts & washers. So, I had a third grinding
station but this one had a big difference. I could run the drill press at
whatever speed I was comfortable with.

So I'm a little crazy and got it to 3400 rpms and it works great!

I wanted to make a 110° graver for a job I'm doing in 14k White gold.
This is the same job I was talking about in the thread about bright cutting.

Making a blank out of the 12 inch rod is easy by scoring the rod with a diamond disc.

You don't have to cut all the way through carbide, you can score it and then break it like glass.
Making sure that Allen screw is tight and everything is aligned on the dual angle fixture.
I chucked up the new blank and cut two index flats at 90° to each other.
Putting the new index end in the dual, I could start cutting the 110° on the other end.

Then cutting the new blank only took about five minute. I think using the higher speed also
reduces wear on the disc. You don't wind up grinding the powered carbide because it spins off.
Also the more speed means, the diamond doesn't take a large a bite, but since your grinding a ten
times the speed. It's ten times quicker.

Continued in the next post.

 

[jimzim75]

Part 2

Hi again.

Then I simple took the blank to the power hone and finished in the normal manner. Using the
600 disc for fine cutting and the laps to put on mirror polishes on all faces.
Finally stropping the finished graver.

Not bad for about ten minutes.

This was the job I was working on. It's the ladies version of a pendant I did about month ago.

I am happy with the results of how the system is working and it will save some time in
making new gravers. I also like the fact that I already had the drill press and the
dual angle fixture. So not having to spend money was great.
I can also be a bit more productive.

Talk to ya later,
Jim

 

[Sam]

Another quality tutorial by Jim! Thanks, Jim, and it's been added to the tips archive. I really appreciate the trouble you go to to share these with us.

 

[fegarex]

Jim,
Great tips! I've used my horizontal mill with a diamond wheel for doing this but frankly the drill press and the dual angle fixture looks easier and faster!
I might advise anyone doing this to watch for overheating tools if you are doing something other than carbide. It won't hurt carbide but some of the others can lose temper if you get them too hot.

 

[John B.]

Hi Jim,
Thanks for the input, a great way to do it for those folks that have the equipment.
Great pictures too, thanks.
You mentioned wanting a stiffer carbide graver and your method made one.
Another way to do this.
Ngraver sells 3/32" square micrograin carbide graver blanks for a low price.
These are very rigid and can be made even more rigid by shortening.
They index in any fixture. The micrograin carbide polishes like a mirror.
They can be shaped and sharpened with the available sharpening systems and fixtures.
Naturally, using your system with the drillpress would speed up any shaping that is required.
This grade of carbide is very fine and wear resistant.
A couple of of these blanks would be a lifetime supply for most engravers.
Best to you, John B.

 

[jimzim75]

Hi John,
I bought some of Ray's gravers while at Reno. When I finally got sorted out after getting home.
I was delighted with the quality of his Ngraver blades.
I put in a order and am waiting for it to come in.
I actually gave my order to Ray himself. What a nice guy.

I really like making and using new graver just for the heck of it.
Thanks for the tips.

Talk to ya later,
Jim

 

[Peter E]

Very good tutorial Jim. Thanks for taking the time to do it.

I had purchased some 1/8" square 10% cobalt steel. What I did to speed up grinding was to buy an 80 grit diamond lapidary disk and use it on the power hone.

The drill press would reduce that time even more but as Rex mentioned, heat must be considered.

Peter

 

[jimzim75]

Hi Peter,
Not with carbides, they can get really hot and not be effected.
High speed steel with cobalt on other hand, with most other types of gravers, will be very much so.

I have a lapidary horizontal grinding wheel, which has a platform for a faceting mast.
The dual angle sits comfortable here for blanking heat sensitive blades.
Doing the chore of blanking with a wet grinder can be nice on a hot summer afternoon with the water
flying everywhere. Luckily it's made of aluminum so you only have to dry off the mast itself to keep
rust free. This unit has four speeds so it's still double the speed of the power hone.

The wall of the grinder has a removable gate, so that the outside of the wheel can also be use to thin point.
It doesn't take much to over heat a blade with a bench grinder and a orange juice can of water.
Don't just hate it when the can gets knocked over. The last time I used the method, I settled on a
Bourbon glass cool the blades in.

Anyway, enough about grinding for tonight.
Talk to ya later,
Jim