Thread: Diamond Tool Holder

Well I made a start on it yesterday. Here are some pictures.
It has yet to be "unuglyed"
Its one takes 1/4" HSS I will make at least one more that takes 5/16", but may add more tool support.

Bob has made one as well and used different angles, will be interesting to compare.

Stuart

Well it's functional, still ugly though.
I put in two bolt holes as it was much easier to do that now than later if I feel it needs two. I think some sort of washer under the bolt will help with the grip but it did the test just fine without it.
I ground the end of the tool by eye to somewhere around 30Degs. Tried it on a piece of Alum, no attempt to work out feeds or speeds, just one adjustment to gee the tool height right. There are a few things to change and clean up a little. I won't be able to do 360deg with it in the tool post. I'll get over that, as the center height is fixed taking it out is no biggy.
So far my thoughts are. For the amount of work they are to make, everyone should try one. But I'll have to test it a little more before I'm 100% sold. I'm still thinking heavy cuts will be its down fall.
Stuart

Stuart,
It looks like it will do the job.The grind on does not want to be any more than you have. The two bolts/washers would be a good idea. A couple of suggestions for you to think about, if you put the largest washer on the lowest bolt and put a smaller one on the top bolt you will be able to machine larger diameter work and still maintain good clearance.Also when doing heavy cuts along the job rotate the tool post to get the tool point slightly behind the front face of the tool ie make contact with the rear of the front face first. I found that positive side rake on the tool wants dig the tool in especially when you come to shoulder as it is well below centre. I hope this makes sense.
Bob

Hi Bob,
Mine looks more than a little rougher than yours lol.
I moved the holder out from the tool post to check a few things. Taking 4mm doc off 12.7mm bar works really well except there is chatter as you slow down and stop. This was with the tool in (I guess we could call it) the facing position. I'll try turning it around a little when I get back out there.
Have you tried radiusing the tip at all?

Stuart

Hi Stuart,
With the tool in the facing position you can get some chatter, angle the tool and it is more like a sliding cut and I am sure you will get better results. I have some rounded nose bits but rarely use them as most of the time I need to work up to shoulder. I take all my heavy cuts with the tool angled to the work then square it up for finishing and shoulder/face cutting. With a razor sharp tool with a small radius and low speed eg 50-100rpm you can achieve a very nice finish even on black steel bar. Have fun.
Bob

Well that wasn't a very successful test
Nasty nasty chatter and it forced the tool down. Maybe I over did the angle?
I'll have a play tomorrow if I get a spare minute.
Stuart

So that was the 1/4 slot you where doing. looks like it works fine.
The one's I have seen are angled in the holder when looking down on them, would the tool benefit from this?

Dave

Hi Stuart,

Looks promising, it seems the idea is sound, and worth a bit of effort to fine tune the angles..

Regards
Ray

Dave, I'm still thinking about this. In the end I'm not sure it matters. Maybe mine won't be a good turning toward the tailstock, I'll try and check tomorrow.

Ray, Thanks I'm pretty please with how well it works so far although, there's some finishing up to do that will let me use less over hang.

I should add, as I said in another thread, the tool angles I generally use are pretty shocking. So to use a woodie analogy I might be comparing my new chisel to an old screw driver rather than an old chisel lol.

Stuart

Dave,
You were right. While I can turn towards a shoulder at the tail stock, I'd need about 100mm of shaft before the shoulder to fit in.
Not sure if I will go with a redesign of what I have or left and right holders.

Stuart

Hi Stuart,

Any chance of a sketch?

I'd like to make one and see how it goes.

Regards
Ray

Ray,
Sure but I wont get a chance before Sunday.
Its not really finished though
Stuart

Here is another one John Hill made. It is a 2 piece clamp style.
Tangential tool holder!

Dave

Hi Dave
Here are a few pictures of the Diamond Tool holder that I made a couple of years ago, I had to just take a punt on the angles. It works quite well and I use it a lot. It is a more complicated design than Stuarts. This one takes 5/16" tool bits and can be used for cuts in all directions. They do require a fairly ridgid lathe as the tool sits out further from your tool post.Mine has a 35 degree angle towards the chuck when viewed from above, and the tool bit is tilted 20 degrees as well.
Bob

Hi Bob,
Really nice work and it looks almost the same as a bought one.
I have no trouble grinding HSS tools, but am thinking of giving one of these a go to see what all the talk is.

For guys looking at making one, I can see a cheap piece of steel would be an old 40mm square box trailer axle, which can be found for near nothing if you keep an eye out.
I have picked up a fair few over the years and the steel always comes in handy.

Dave