Forum sponsored by:
Diamond tool holder.
| Frank Dolman | 20/02/2010 23:21:44 |
| 106 forum posts | Excellent though most aspects of these ingenious devices are, it seems to me that there is a difficulty that has not been mentioned. On intermittent
cuts, there will be a tendency for the tool to be driven down into the holder
like a tent peg and some sort of positive means of preventing this would
be a good idea. |
| mgj | 20/02/2010 23:30:27 |
| 1017 forum posts 14 photos | Agreed Frank - I thought that, but it seems to be OK on mine. The commercial one has an even more powerful clamp. |
| chris stephens | 21/02/2010 00:52:49 |
| 1049 forum posts 1 photos | Hi Frank,
A positive stop is not really necessary, but agreed, you would think that it were. The gripping power of just a 5 or 6mm Allen screw head is enough to hold the tool bit in place. On the commercial item there should be more than enough grip. There is some merit in having a tool bit that will slip under extreme duress, but as the tool cuts so easily there is more tendency for the tool to cut than to slip. If it should slip there is no harm done, the tool will come out of engagement with the work, you just have to reset to centre height and start again. All it would show is that you were a bit ham fisted in your knob twiddling.
I, at first, thought of a positive stop, not to hold the tool securely but to aid resetting after sharpening. I quickly dismissed this as impractical because the tool bit gets shorter every-time you sharpen it, rendering the stop useless. What is needed is a gauge to set the cutting tip back on centre height after sharpening.
Going back to an earlier post, although I am a self appointed spokesman for these tools, I did a count up of my QC tool holders this evening, and only one of the 17 had a Tangential in it, make that two the other is a GHT radius turner. The rest is a mixture of assorted tools, both HSS and carbide, plus a DTI and a Knurling tool. I like to have both hands free to work my lathe.
 chriStephens |
| ivan kustura | 21/02/2010 10:53:17 |
| 4 forum posts | G'day to all.
Thanks Chris for welcoming me, greatly apreciated.
 Regards. |
| Les Jones 1 | 21/02/2010 12:06:06 |
| 2292 forum posts 159 photos | Hi Chris, This is a reply to your post at 18:43 yesterday. I went down to my workshop this morning to have another look at the tool holder. I milled the top of the clamp screw flush with the side face of the holder. (Rather than facing it in the lathe.) This gave me the required clearance and left enough metal left on the screw head. I have put a few pictures of it on an experimental web site I am building. I did try ticking the remember me button a few days ago and it seemed to solve the logging out problem but I forgot to do so yesterday. Les. |
| Paul Boscott | 03/07/2010 14:07:31 |
 99 forum posts 21 photos | All
Just got a Diamond tool / holder from Eccentric Engineering UK it works very well
Paul |
| chris stephens | 03/07/2010 19:31:06 |
| 1049 forum posts 1 photos | Hi Paul,
Another convert?
Welcome to the club (of enlightened turners).
chriStephens |
| Mark Bus | 05/07/2010 17:03:04 |
| 50 forum posts 21 photos | Hello everyone,
I finished making one of the MEW 156 toolholders two weeks ago and I just want to add my praise . I tried it out on different types of steel , brass, and bronze and it worked well on everything. I liked it so much I made a second one to hold .250" toolbits. This one has a about a .500" shank with the bit holding screw lowered slighty.On this holder I used a truss headed machine screw to hold the bit; no nut. It seems to hold the toolbit securely. Apparently a truss head machine screw has a larger head than a regular machine screw.
I know the toolholder won't work in all situations but I appreciate the ease of grinding the toolbits. I've never been able to get the hang of grinding toolbits freehand and I've never gotten around to building a proper grinding rest with fences.
I too would like to see that description of the threading toolholder. And does anyone have any ideas about making a round bit toolholder?
For what it's worth I have a Chinese mini-lathe.
Mark |
| _Paul_ | 05/07/2010 19:23:45 |
 543 forum posts 31 photos | Mark, I'm keen to make one of these also do you have any pictures of yours you could post please Regards Paul |
| chris stephens | 06/07/2010 01:11:14 |
| 1049 forum posts 1 photos | Hi Mark,
If that was my threading toolholder you were referring to, it was on show at Sandown last year, but no one took much notice of it. The trouble with putting things on show, especially toolholders, is that they are so very much unspectacular when just sitting on a stand. The only way that any one can see the benefit of a particular tool is by watching it wok, or better still using it.
have not written up the way of making it, yet, but due to various restrictive practices the only place that I would be tempted to do a write up is in the SMEE journal. Thinking of which, there is a picture in the latest issue (photo 7 page41) of my Mk 4 tangential toolholder, this one looks a bit like an Eccentric but is of one piece construction. If you are not a member of SMEE shame on you but I am sure you must know someone who is and have a look at their copy.
chriStephensI |
| Ray Lyons | 08/07/2010 22:06:31 |
| 200 forum posts 1 photos | Hi Everyone, I saw the item in No 156 and when visiting the Midlands Exhibition last October,bought a suitable piece of metal and put it in the stock rack when I got home. Forgot all about it until last week, when looking for something else, this piece of bar popped out. I immediately pulled the item in 156 and copied it for use in the shed. I did make some changes, increasing the length to ensure all clamping screws on the toolholder are gripping, Cutting a V instead of a channel to hold the tool and threading the bolt direct into the tool rather than using a bolt. I also made a square washer to act as a clamp on the toolbit. My 1/8" toolbit which I pulled from stock is something other than HSS, much too hard for the purpose, something special. Could be something I bought some time ago but forgotten now, so I had to use the next nearest, a piece of 3/16" HSS, When I tried the tool in the QC tool holder on my Myford S7, it would not fit, too high by about 1/4". The only way I could use it would be to remove the toolholde and go back to the old clamping method so I tried it on my Warco BG600. It fitted perfectly and I was impressed with the trial cut on a piece of 11/2" MS. I then tried a deeper cut only to find that chatter set in when the toolbit was pressed back into the tool. On examination, it was obvious that the 3/16" was relying on the grove for location only so tonight, I cut a deeper V and again tried it on the Warco. I made two cuts, one about 1/16" followed by another much deeper. Very impressed, this time it was an old piece of heavy gauge galvanised pipe, not the best of steel but the cut was clean and without cutting fluid, the swarf was very hot and discoloured.
I now intend to make another tool for the S7 but with the head set down by about 1/4" and a slightly greater width of body to take the extra depth needed for a 1/4" toolbit.
Putting this on the must buy list for the Bristol Exhibition next month. |
| John Shepherd | 09/07/2010 14:42:00 |
| 222 forum posts 7 photos | There is probably enough endorsement already to justify owning one of these tools but I have just finished making one to the basic design by Peter Boonham in MEW but using a 3/16 toolbit and I am very impressed with the results so far.
Most importantly I have just been able to easily machine a small eccentric for a 1" Minnie lubricator that has previously proved impossible for me using inserted carbide tooling.
For the same reason that you would not have just one spanner in your toolbox, I will not be making my other tooling (that includes HSS, brazed and inserted carbide) redundant but I can see that the tangential will spend a lot of its time in the toolpost.
On the basis that good value is not necessarily cheap, had I bought the commercial version I am sure I would have regarded it as good value for money if it performs as well as the home made one.
Thanks to Peter for the article and the inspiration to make it. |
| Mark Bus | 09/07/2010 16:24:14 |
| 50 forum posts 21 photos | Hi Paul ,
I'm working on trying to post some pictures. i don't have a computer so it's difficult ; I have to rely on the kindness of friends.If all else fails I can talk you thru how I made the toolholder.
Mark
|
| John Haine | 01/01/2011 14:29:22 |
| 5563 forum posts 322 photos | Well I spent quite a while making my own version last winter, but only yesterday got around to grinding a tool up for it. After machining a bit more off to obtain enough clearance I found it works a treat, though I think I need to have a slightly greater clearance on the tool. So, a question to those who have used these a lot: though it cuts very easily, the finish isn't wonderful, I think because of the very sharp tip. How much rounding do you give the tip, and how do you do it? I rubbed the appropriate edge of the 3/16 toolbit on a diamond lap and just took the sharp corner off. Is there any other secret to getting a good finish? All suggestions gratefully received! |
| Michael Cox 1 | 01/01/2011 15:02:09 |
| 555 forum posts 27 photos | Although the tangential toolholder described in MEW 156 is not difficult to make I have designed a similar tool which avoids having to set up compound angles for milling. The holder is easily made from a piece of 1/4" steel plate. Full details are on my website:
Mike |
| chris stephens | 01/01/2011 15:47:15 |
| 1049 forum posts 1 photos | Hi John,
It's been a few years since Ascot!
Now about your problem, I usually just round the corner with a few strokes on a diamond lap down the whole length of the HSS bit, don't just do the top or you will loose clearance. The angles you need to work to are 12 deg forward and to the side and grind the tool's top to 30deg. If you use a clamp screw and it touches, can you lower the holder and have more tool projection to give better clearance?
When you say you don't get a good finish, is that with a roughing or a finishing cut. The finish cut (2-3 thou) will be be better, unsurprisingly. One way to improve your finish is to make a cut and then, while the work is still turning, slowly run the tool backwards if the tool is sharp you will get "angels hair" and a pretty damn good finish. If you want a tool for "super" finish, raise the tip slightly above centre and cut backwards, this gives you a shearing cut with a tool of "infinite radius" and a near perfect finish, depending on material of course.
Another thought occurs, how are you sharpening your tool? Do you merely grind or do you hone after? Personally I find honing counter-productive, I grind with an 8" 80 grit wheel and leave it at that. This gives a fairly flat curve to the top which is a bit stronger than say a worn 6" one would do. Which type of holder do you use for sharpening, I find the 30 deg Vee type to be superior to the commercial design, but that is just my jaundiced view. The commercial design is great for sharpening threading bits, so should not be dismissed.
If you have a specific question you can PM me, or if the others might benefit ask in this open forum.
Are you going to Ally-Pally?
chriStephens
|
| wotsit | 01/01/2011 19:09:56 |
| 188 forum posts 1 photos | The following link has some useful info on tangential tools and toolholders - may be of interest (whole site is pretty good IMO) KeithW |
| John Haine | 02/01/2011 16:56:22 |
| 5563 forum posts 322 photos | Thanks for the suggestions Chris. I took the same approach to rounding, but maybe it needs a few more strokes. My holder has the clamp screw from the opposite side with a clamping piece in the tool slot (which is twice as wide as in the simple design - seemed a good idea at the time but was fiddly to make). Clearance problem was at the front, but easily sorted. I was using a finish cut of 0.1mm (4 thou) under CNC, but using a turning wizard which only cut towards the h/stock ... I need to play around a bit with speeds and feeds I think, and maybe rewrite the wizard to allow a finish cut in the opposite direction. Good idea to try finishing with the tool a bit high, I'll give it a whirl. I ground the tool on the Quorn with a cup wheel, this gives a flat face, and if I finish off with passing the tool across the wheel until it sparks out it has virtually a mirror finish. However, first impressions are that this is a great tool. Yes, I should be at Ally Pally, are you demonstrating again? John. |
| George Scollay | 02/01/2011 18:57:38 |
| 19 forum posts | Hi Chris,
You will not be disapointed with the tool,I purchased one about a year ago and never looked back I know it is a bit expensive but everything is there and it is so easy to sharpen again even for a beginner as I was at the time (and still learning) |
| chris stephens | 02/01/2011 19:17:19 |
| 1049 forum posts 1 photos |
Sorry if this sounds like a PM on an open thread;
Hi John,
Yup, will be on the SMEE stand again, we will be allowing anyone who wants a go to have a try on our new SuperC3, which was generously donated by ARC. One of the tools will, most likely, be a Tangential tool so you can have a look provided the youngsters don't get in the way.
I tried sharpening my bits on a Quorn, but had more success, no change that, it seemed to be better on an ordinary grinder. I wonder if the very fine striations left be a grinder act like little saw teeth and help the cut, rather like scissors only work properly with a little roughness.
chriStephens
PS I have you, John, a PM
Edited By chris stephens on 02/01/2011 19:22:41 |
Please login to post a reply.
Magazine Locator
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
Sign up to our Newsletter
Sign up to our newsletter and get a free digital issue.
You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy
Latest Forum Posts
- *Oct 2023: FORUM MIGRATION TIMELINE*
05/10/2023 07:57:11 - Making ER11 collet chuck
05/10/2023 07:56:24 - What did you do today? 2023
05/10/2023 07:25:01 - Orrery
05/10/2023 06:00:41 - Wera hand-tools
05/10/2023 05:47:07 - New member
05/10/2023 04:40:11 - Problems with external pot on at1 vfd
05/10/2023 00:06:32 - Drain plug
04/10/2023 23:36:17 - digi phase converter for 10 machines.....
04/10/2023 23:13:48 - Winter Storage Of Locomotives
04/10/2023 21:02:11 - More Latest Posts...
- View All Topics
Support Our Partners
Shopping Partners
Subscription Offer
Latest "For Sale" Ads
- Reeves** - Rebuilt Royal Scot by Martin Evans
by John Broughton
£300.00 - BRITANNIA 5" GAUGE James Perrier
by Jon Seabright 1
£2,500.00 - Drill Grinder - for restoration
by Nigel Graham 2
£0.00 - WARCO WM18 MILLING MACHINE
by Alex Chudley
£1,200.00 - MYFORD SUPER 7 LATHE
by Alex Chudley
£2,000.00 - More "For Sale" Ads...
Latest "Wanted" Ads
- D1-3 backplate
by Michael Horley
Price Not Specified - fixed steady for a Colchester bantam mark1 800
by George Jervis
Price Not Specified - lbsc pansy
by JACK SIDEBOTHAM
Price Not Specified - Pratt Burnerd multifit chuck key.
by Tim Riome
Price Not Specified - BANDSAW BLADE WELDER
by HUGH
Price Not Specified - More "Wanted" Ads...
Get In Touch!
Do you want to contact the Model Engineer and Model Engineers' Workshop team?
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.
Digital Back Issues
Donate
Register
Log-in
Model Engineer Magazine
- Percival Marshall
- M.E. History
- LittleLEC
- M.E. Clock
ME Workshop
- An Adcock
- & Shipley
- Horizontal
- Mill
Subscribe Now
- Great savings
- Delivered to your door
Pre-order your copy!
- Delivered to your doorstep!
- Free UK delivery!
All Forum Topics > Beginners questions > Diamond tool holder.