The Diamond Tool Holder

Duncan,

Both these were for 1/8 toolbits, so would suit a small lathe, and included drawings of the jig for resharpening.

Autumn 2009 for the one needing setting compound angles to machine the shank.

The version with a trapezoidal shank (to avoid the need for setting compound angles to machine it) was in August 2011.

A friend made both RH and LH versions, to use on his mini lathe.

Howard

fat fingers again!

Edited By Howard Lewis on 20/01/2019 16:55:35

If you give them a call and ask for a quote on express post they should be able to sort it for you and it is not that much more expensive , you should have it in a couple of days at the most .

My difficulty was making a neat fracture of a 3 inch length of the HSS toolbit. Then, as said found that it fouled the Top slide when trying to rotate the 4 way toolpost.. My solution was to slacken off the clamp, a long way so that the toolpost would lift clear of the pawl so that it could be rotated backwards before reclamping.

The American toolpost is an invention of the Devil, as far as i am concerned. Four way every time for me (which when I made a rear toolpost, it was a fourway, also!)

Howard

Forgot to say (if it needs to be said) that a Centre Height Gauge makes setting the tool after resharpening, an absolute doddle. The genuine article seems to lift the bit a tiny amount when the Allen screw is fully tigthened, but hardly enough to cause a problem.

Tangential tools have a long history, stretching back to the early 1900s, and keep being rediscovered. None the worse for that, though!. Still a boon.

Howard

For cutting off HSS I use an angle grinder with a thin cutting disc mounted in a pivoting stand.

My DTH would foul the topslide even without the toolbit, unfortunately.

I have never used an American toolpost and have no plans to do so!

Thanks Howard, both references consulted, another job on the to do list

Pictures please when you’ve done it!

Question, I sharpen the bit for mine on a belt sander so the grind is flat. I noticed on the video that sharpening on a bench grinder gives a noticeable hollow grind. Is there any advantage or disadvantage to this? I hasten to add that mine cuts fine, just wondering.

Vic

Hollow grind gives two line contact for the honing stone so its much easier to hone for a really sharp cutting edge. Just the job when you want to touch up a tool in the machine.

With a flat grind its really easy to tilt the hone a fraction at the ends and beginning of a stroke. Basically making the tool blunter rather than sharper which, probably, isn't quite what was intended.

Not sure which is harder. Honing dead flat or filing dead flat. After over 4 1/2 decades of home shop metal bashing I still need a following wind, a touch of luck and the shop gremlins temporarily distracted to consistently achieve either.

Close no problem.

Dead on. First time. Every time. Now thats different!

Clive.

Thanks for that info xd351,never thought of that, I,m

not actually sure of the size I want,my lathe is a smart and brown model A with the standard four tool tool post if anyone knows which size tool.

Graham.

I've had a diamond tool holder for years and I love it. The surface finish I get on steel for general turning has improved no end.

I'm not great at grinding tools so in the past I've cut threads on the lathe using cutters with no top rake. The surface finishes were usually poor and needed finishing off with thread nuts to be useful. I was aware from their videos that the diamond tools could be used to cut threads but couldn't see how to grind them. I e-mailed Gary at Eccentric Engineering and he was kind enough to grind both 55 degree and 60 degree threading tools for me. They work brilliantly with the metal peeling smoothly off the work and giving a beautiful surface finish even on steel which is of dubious quality.

After seeing what the tools look like, and practising grinding them with key steel on the jig that came with the holders, I found it to be quite easy to do.

Regards,

Alan

I made my own that use 2mm square and 3mm round best german carbide.

https://www.homemodelenginemachinist.com/threads/carbide-tangentials-for-small-lathes.25950/

I use a homemade M8x0.5 Unbrako screw for clamping to day

Edited By Niels Abildgaard on 21/01/2019 05:50:54

I made both left and right handed tools from the article in MEW. The same info is on "mikesworkshop" site.

Graham,

The Eccentric Engineering web site explains how to choose the correct size tool to suit your lathe. The cutter height is adjustable but I would get the largest holder that will fit into your toolpost rest for best rigidity.

Paul.

Thanks for your info Paul, unfortunately I am 10,000miles away from the workshop and don't know the measurement from the base of the tool post to the centre height and won't be home for two weeks but thank you for taking the trouble to post.

Graham.

Graham

According to the manual and sales brochure the standard tool size for the Smart & Brown Model A Mk1 is 3/8 x 5/8 deep. I assume that is for the American style lantern toolpost as that is the one listed in the standard equipment section. A four way being an option.

For what its worth the 1024 is also listed as using 5/8" deep tools and that did come with a four way as standard.

Unfortunately we don't have any more detailed information in the files on the Smart & Brown Yahoo group. If you aren't signed up I could ask.

Clive.

I bought one of these in 1980 something. Work took to me to Australia so I arranged to buy 8 plus grinding fixtures, not all for me! I think that there were only two sizes then, I had one of each.

Initially I was impressed, they worked well enough on my relatively light weight lathe. I upgraded to more rigid machinery, and found that the the tool would move downwards under a heavy cut/feed. Could also be the source of vibration. Easily sorted with the large butt-welded HSS tooling I had. Not as easy to sharpen though! For a while longer I used the diamond tool holder as a finishing tool until I got to grips with disposable tips. The tool holders went when I upgraded the smaller of my two lathes, something I have occasionally regretted.

A couple of criticism I have of them is how often is an internal square corner needed? Best avoided if at all possible. A good friend who worked in a toolroom ground radii along the edge of several pieces of HSS for me. Was this something offered by the supplier at on time?

Also, tougher steels would soon bring on the need for frequent sharpening that (near) square corner could be a bit delicate.

John

Thanks for the reply Clive,didn know about the s and b Yahoo group, I'll see about joining

Regards Graham.

Quick picture of mine, more in my album.

I made the tool holder as per Mikesworkshop for my ancient Drummond lathe and as a beginer found it to be one of the best tooling parts that I have ever made. So easy to sharpen for the beginer. I have just made two more to suit my Myford/Drummond M. Have mounted them on a Norman Patent style tool post mounted on the crosslide.

John

Can attest to what John said about tool being pushed downwards on a heavy cut, but in my caseI hadn't tightened the holder enough.

That moving down, however, saved my bacon when I had a dig-in, due to not paying attention, the toolbit being pushed clear of work.

Here's my Edge gizmo for setting the toolbit heights, and what a pleasure using it:

Upside down tools a little tricky to set in my rear QC though, but I can put up with that.

Geoff - Ham & cheese followed by Rooibos tea