Drummond Round Bed Lathe No 1

[rtbcomp]

I'll be getting another for the other lathe as that didn't come with a toolpost, then I'll have 8 tool holders to share between the two machines.

 

[MattF]

Any info on the QCTP?

 

[rtbcomp]

https://www.ebay.co.uk/itm/Universa...rentrq:3fa78b851650ad41723f145bfffa5323|iid:1



The whole construction is aluminium.

Been giving it a bit of a workout today. Decided to turn a point on the end of a M10 HT bolt, had a problem with the workpiece riding over the parting tool when the diameter was down to about 2mm. I could feel movement between the tool holder and the body of the QCTP, but there's absolutely no movement if you try to force it by hand. There is also backlash in the cross slide thread which allows the tool to move forward when the tool grabs. Added to that there's slight play in the spindle. I adjusted that out but it returned.

 

[Seadog]

Piston type QCTPs are not rigid. I had the same problem too when parting. Went to a wedge type and the problem disappeared.

 

[rtbcomp]

^^ I've heard that before, but it's a case of you spends your money and takes your choice, are there any budget wedge type QCTPs out there?

I think the biggest problem on my setup is the backlash in the cross slide screw, I've had another go adjusting the spindle bearing and parted off a 3/4" dia bar OK, just need to take it slowly.

 

[rtbcomp]

Made a chuck-mounted dead centre




Went very well in spite of the fact I could actually see the tool moving in the QCTP. Just had to take the pointed end very slowly, with a light cut and a sharp tool.

Piston type QCTPs are not rigid. I had the same problem too when parting. Went to a wedge type and the problem disappeared.

Any chance of a link to the sort of thing you mean?

 

[Seadog]

https://www.arceurotrade.co.uk/Cata...s/Tool-Posts/Model-111-Quick-Change-Tool-Post

 

[eLuSiVeMiTe]

Im using one of these I bought sh from here

https://www.ebay.co.uk/p/RDG-Tools-...rd-Lathe-With-2-Holders-Swiss-Type/1057399841

Been nice and rigid.
Only issue other than the cast handle
Im struggling to find spare holders.

Will make some with a better height adjustment

 

[rtbcomp]

I've upgraded the motor control to a system that uses input from the tachometer to keep a constant motor speed.

I got it from this guy on Ebay https://www.ebay.co.uk/usr/motor.uses?_sp=p2488211.m41214.l9763



If you want to do some research Google TDA1085C, this is the controller chip.

This is the revised circuit

 

[rtbcomp]

I've just parted a 1" diameter bar without jamming or throwing the belt, which it used to do regularly. With this system I can use one hand to feed the tool and the other to hold the oil can, I don't need the 3rd hand to keep the speed under control.

 

[Robotstar5]

I've just parted a 1" diameter bar without jamming or throwing the belt, which it used to do regularly. With this system I can use one hand to feed the tool and the other to hold the oil can, I don't need the 3rd hand to keep the speed under control.

We don't need to know what you were doing with it instead

 

[winchman]

Excellent I have just bought my first drumming its a 1908 model!

 

[rtbcomp]

https://www.ebay.co.uk/itm/Universal-Quick-Change-Tool-Post-Holder-Kit-Set-for-7-x10-12-14-Lathe-Tool-Set/253043771912?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908105057&meid=9849d2320f604ae8a4c813608abd69bc&pid=100675&rk=6&rkt=15&sd=232776570816&itm=253043771912&_trksid=p2481888.c100675.m4236&_trkparms=pageci:9443c793-a0d8-11e8-9d05-74dbd180dd4f|parentrq:3fa78b851650ad41723f145bfffa5323|iid:1

View attachment 150329

The whole construction is aluminium.

Been giving it a bit of a workout today. Decided to turn a point on the end of a M10 HT bolt, had a problem with the workpiece riding over the parting tool when the diameter was down to about 2mm. I could feel movement between the tool holder and the body of the QCTP, but there's absolutely no movement if you try to force it by hand. There is also backlash in the cross slide thread which allows the tool to move forward when the tool grabs. Added to that there's slight play in the spindle. I adjusted that out but it returned.

This has had some use over the weeks and unfortunately it's not holding up well, although it feels solid you can definitely see the tool moving under load and there are wear marks where the height adjusting screw abuts the body.

So, I made these, the Drummond original is on the left



I don't have a mill so they were made from three blocks of mild steel welded together.

You set the height of the tool with the bottom screws and clamp it in place with the top ones. So far so good and it's nearly as quick to change tools as with a QCTP, you just have a holder for each tool.