Harold Hall simple grinding rest

Technical Ted

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Just finished phase I of making Harold Hall's simple grinding rest... Drew it up in Fusion 360 first and converted it to inch units from metric. Now, to buy a dedicated bench grinder and make the required accessories for tool holding and end mill sharpening and get everything set up and operational!

This should keep me busy for a while!

Ted

20171004_161628.jpg 20171004_161703.jpg Simple T&C Grinding Rest v18.png
 
Nice job, looks like you stoned everything too. His grinder rest is on my list of tooling I want to make.

Rich
 
Nice job on that you would not by chance have the converted drawings or the 360 file we could get would you.
 
Great job. Any possibility you could share the dimensioned drawings or the F360 model?
 
Nice job on that you would not by chance have the converted drawings or the 360 file we could get would you.

Out of respect for Harold I wouldn't feel right giving out his drawings. The complete plans are in his book "Tool and Cutter Sharpening" and I think I got it on Amazon for a little over $10. Pretty cheap.

If I designed it myself I would be more than happy to share. I don't get an income from selling books. Actually, going through that conversion process helped me get a better handle on metric measurements, so working from his original drawings was a plus.

Sorry,
Ted
 
I have 3 copies, or I should say 1, I wore out the other 2. I can convert them myself, just being lazy.

Rich
 
Nice job! Did you pick up a set of magnetic bases for mounting the rest, like Harold does in his video? Looks like a great idea.

I have 5 of Harold's books and visit his website frequently. He's an ingenious person and I'm amazed at the designs he comes up with. I've already made a few of his tools; the lining tool, his end mill sharpening fixture (ends only), slitting saw sharpening jig and I'm currently about 3/4 of the way through completion of his end mill sharpening jig (for both the ends and flutes). After completion of the end mill jig I was going to start on the complex grinding rest but have now changed my mind and will go with the simpler one as you did.

I did the same as you and converted all hole sizes and threading to imperial sizes. But did it in pencil on the drawings in the book. Computer would be much better method. Wish I could get my hands on an inexpensive metric drill index, then I wouldn't bother with the conversions.

What did you use for the 1" plastic ball and where did you get it? Does it need to be a hard plastic?
 
Nice job! Did you pick up a set of magnetic bases for mounting the rest, like Harold does in his video? Looks like a great idea.

I have 5 of Harold's books and visit his website frequently. He's an ingenious person and I'm amazed at the designs he comes up with. I've already made a few of his tools; the lining tool, his end mill sharpening fixture (ends only), slitting saw sharpening jig and I'm currently about 3/4 of the way through completion of his end mill sharpening jig (for both the ends and flutes). After completion of the end mill jig I was going to start on the complex grinding rest but have now changed my mind and will go with the simpler one as you did.

I did the same as you and converted all hole sizes and threading to imperial sizes. But did it in pencil on the drawings in the book. Computer would be much better method. Wish I could get my hands on an inexpensive metric drill index, then I wouldn't bother with the conversions.

What did you use for the 1" plastic ball and where did you get it? Does it need to be a hard plastic?

I just ordered a dedicated bench grinder last night ( Powertec BG600 6-inch - https://www.amazon.com/gp/product/B004A8ZA94/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 ) and plan on ordering two mag bases today. I've already got some old stones that were used by the tool grinders where I used to work so all I have to do there is make the bushings for them for mounting. I also have to figure out where I'm going to put this setup... maybe on a table with wheels so I can move it around to get it away from machines especially when dressing a wheel.

I bought his book "Milling a Complete Course" as well and most likely will build his advanced rest in the future. I can have one mounted for each wheel on my grinder. I started with the simple one since I had the material on hand for it and it was a quicker build. When I converted dimensions to inch I rounded to the nearest 1/64" or 1/32" inch instead of just a direct conversion, always rounding up. This certainly wasn't necessary, but it seemed to make sense to me at the time. I also went with a little bigger screw sizes when I could (#6-32 being the smallest I went) because I had the screws and taps and bigger is easier and safer if you can use them.

I didn't use a plastic ball, I made one out of steel with the ball turner I made (see my post on this site for that). I sized the ball so that the two mating clamping pieces were parallel. I wondered about using plastic and wondered whether Harold had a "gripping" reason for plastic or if the plastic ball was just more readily available. I do have some Delrin I could have used, but decided to try steel first and see how that worked out. Steel seems to be working quite well, but time will tell since I haven't actually used it yet!

Are you or did you go with cast iron for the bearings for the end mill jig? I don't have any CI, but I do have both brass and bronze and was thinking about using some of it. I like to use any material I have on hand if I can since half the fun of making this stuff is to make it on the cheap out of what you have. I'm thinking that I'll have less than $100 in this project including the bench grinder and I don't think that's too bad for being able to sharpen your own cutting tools.

Ted
 
I did the same thing with the threading sizes, bigger is safer, as long as there's enough "meat" on the part.

I did use CI for the bearings. I didn't have any other materials I could use, other than steel, so I ended up buying some CI from a machine shop.

I didn't use a plastic ball, I made one out of steel with the ball turner I made (see my post on this site for that).

Crap, now I have to make a ball turner too, lol. Odd thing about this hobby (for me anyways) is that I don't have any real work to machine and spend pretty much all of my time making tools for some future project or making things to maintain the stuff I already have.
 
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