Bazyle | 21/12/2022 14:00:18 |
![]() 6956 forum posts 229 photos | Posted by Martin Connelly on 21/12/2022 09:03:49:
because two parallel vee shaped mountings are always going to be fighting each other if there is even the slightest error, No, the two Vs are not meant to both be fitting perfectly to the corresponding projections. Either the two outer or the two inner faces should contact only. If you want a V to define the alignment you make a plain flat face where the other V would be; this is a good way to make your own as actually not so much precision is needed. |
Simon Johnson 2 | 06/01/2023 16:00:36 |
9 forum posts | I've only just picked the thread up.
For what its worth, I have a 'modern' Myford QCTP for my ML10 purchased about 5 years ago. The tool holders are all stamped with the W or M so this probably shouldn't be seen as a mark of age or originality.
I think Bison/Toolmex still make Myford size Dickson type QCTP for those with an eye to quality and matching deep pockets |
Peter Simpson 3 | 06/01/2023 16:57:26 |
122 forum posts 2 photos | I got a full refund less the cost to ship the items back. I will try some RDG one's when I get round to it. |
Bo'sun | 06/01/2023 18:22:11 |
754 forum posts 2 photos | I'm not surprised that "after market" Dickson type tool holders can be a bit of a gamble. Four things need to be made to to a "standard" with close tolerances. Namely, the tool post, the tool holder, the top hat clamp and the cam. I guess over time, some of the tolerances have been slackened off for reasons of economy. As gets said many times, "you get what you pay for". I naively thought that buying so called "T51" holders would be OK, but I'm afraid not. |
Bob Unitt 1 | 06/01/2023 19:48:52 |
![]() 323 forum posts 35 photos | Posted by Simon Johnson 2 on 06/01/2023 16:00:36: The tool holders are all stamped with the W or M so this probably shouldn't be seen as a mark of age or originality. My understanding is that the 'W' holders were made by a particular sub-contractor in the south-west. I got mine in 1997, is there any chance that yours were old stock ? |
ChrisLH | 06/01/2023 21:08:47 |
111 forum posts 7 photos | I was lucky that some kind soul at an exhibition alerted me to the fact that there were variations. Just having looked at my stock of holders purchased at least 20 years ago they are all marked with a "W" and fit perfectly. But I agree with Martin C., a vee and a flat has always been the way to go with lathe ways so why not with tool holders ? I can't agree with Bazyle, as to my mind, fitting on the inners or the outers of the vees creates part of a near cylindrical surface where positioning would be dependant on mating and angularity of very narrow flats. Quite easy to clamp down in a variety of positions. I await the protests! |
ChrisLH | 06/01/2023 21:09:46 |
111 forum posts 7 photos | I was lucky that some kind soul at an exhibition alerted me to the fact that there were variations. Just having looked at my stock of holders purchased at least 20 years ago they are all marked with a "W" and fit perfectly. But I agree with Martin C., a vee and a flat has always been the way to go with lathe ways so why not with tool holders ? I can't agree with Bazyle, as to my mind, fitting on the inners or the outers of the vees creates part of a near cylindrical surface where positioning would be dependant on mating and angularity of very narrow flats. Quite easy to clamp down in a variety of positions. I await the protests! |
Pete. | 07/01/2023 00:09:37 |
![]() 910 forum posts 303 photos | When I purchased my Boxford Industrial Lathe it had the original Boxford branded Dickson tool post and 2 holders, one standard and one a part off tool holder. I had a look around for extra holders and came to conclusion that to buy OE parts I'd most likely have to source them individually on Ebay at £50 to £70 each with individual postage, so it would have turned in to a very expensive addition. I decided to just buy the Multifix size A tool post as any future tool holders could be bought new with a guarantee of fitting for less money than OE Dickson holders sell for second hand. My Multifix order was about £400, someone offered me £100 for the original Dickson and 2 holders, so it only set me back about £300 to upgrade to a Multifix set up. |
samuel heywood | 07/01/2023 00:33:47 |
125 forum posts 14 photos | Posted by Peter Simpson 3 on 19/12/2022 08:10:32: ......The tools could not be set at centre height so I milled a millimeter of all the tool.
Wow! You milled 1mm off a set of hss tools?? Respect! Call me a luddite, i never did get QCTP's . My minimal research prior to buying a mini lathe suggested it was an almost essential accessory, so i bought with the lathe. Only used it a couple of times, Standard 4 way TP & shims are quick enough & easier for me. |
Michael Gilligan | 07/01/2023 09:04:08 |
![]() 23121 forum posts 1360 photos | Posted by Bazyle on 21/12/2022 14:00:18:
Posted by Martin Connelly on 21/12/2022 09:03:49:
because two parallel vee shaped mountings are always going to be fighting each other if there is even the slightest error, No, the two Vs are not meant to both be fitting perfectly to the corresponding projections. […] . I spent a while yesterday, searching Espacenet for a definitive description of this fundamental feature, which I presumed would have been patented by Dickson … I failed. I did however locate two related patents that are worthy of note: https://worldwide.espacenet.com/patent/search?q=pn%3DGB1127018A https://worldwide.espacenet.com/patent/search?q=pn%3DGB1215583A The first [which I have referenced previously] covers the Indexing Mechanism The second covers a useful Tool-Setting Fixture. If anyone does find the original patent for the ToolPost and Holders, it would be helpful to reference it here. MichaelG. . P.S. __ the Aloris design, however, is very well documented: https://worldwide.espacenet.com/patent/search?q=pn%3DUS6230595B1 Edited By Michael Gilligan on 07/01/2023 09:16:04 |
JohnF | 07/01/2023 09:30:50 |
![]() 1243 forum posts 202 photos | Posted by Michael Gilligan on 07/01/2023 09:04:08:
https://worldwide.espacenet.com/patent/search?q=pn%3DGB1215583A
The first [which I have referenced previously] covers the Indexing Mechanism The second covers a useful Tool-Setting Fixture. If anyone does find the original patent for the ToolPost and Holders, it would be helpful to reference it here. MichaelG. . Interesting Michael, the first item the indexing 4-way tool box is from memory the same as the one originally fitted to Smart & Brown Model A & 1024 toolroom lathes in the 1960's The second I used this fixture around 1967/68 with Dickson tooling on a 1024 lathe when evaluating an early DRO system made by Ferranti the fixture being used to preset tools to a zero point. The system did not work particularly well and at that time the cost was far too high ! A two axis readout was more than the cost of a new S & B 1024 at the time. One must also keep in mind disposable tipped tooling was still in its infancy then - times have changed ! John
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Anthony Knights | 07/01/2023 09:35:35 |
681 forum posts 260 photos |
Call me a luddite, i never did get QCTP's . My minimal research prior to buying a mini lathe suggested it was an almost essential accessory, so i bought with the lathe. Only used it a couple of times, Standard 4 way TP & shims are quick enough & easier for me. Me too. For me it is easier to make a new toolpost than spend lots of beer tokens on QCTP gadgets. It might be different for people with bigger machines, but a CL300 does for me.
Edited By Anthony Knights on 07/01/2023 09:41:26 |
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