Damaged Screws & QCTP help!!!

[duncan webster 1Participant @duncanwebster1]

Posted by Margaret Trelawny on 30/07/2023 00:12:45:

………..

I am pleased to say we got the damaged screws out! As suggested, starting with a 2mm drill, worked all the way up in .5mm increments carefully until we were able to gently wind a 5mm tap into the holes which split the remainder of the cores and they wound out. Yey!

……….

excellent, now I can breathe again! I think Jason is correct that the old stud is useable

[Margaret TrelawnyParticipant @margarettrelawny34058]

Thanks gentlemen. I have just purchased the relevant machine screws with socket fitting from GWR as per your recommendations.

Jason – I am not sure the original stud is long enough? I tried to photograph it against the QCTP but the phone camera distorts it somehwat. The stud collar is aligned with the base of the QCTP in the pics and to me, looks about 15mm too short?

[Margaret TrelawnyParticipant @margarettrelawny34058]

Sorry about the higgledy piggledy post above – adding photos on a phone is tricky!

[JasonBModerator @jasonb]

Yes looks a bit short to use the existing nut.

What is the diameter of the thread on the old stud, as I said a custom nut with a shoulder that will reach down into the toolpost hole may be all that is needed.

Also to check the size of toolpost to suit your machine what is the thickness from bottom of the old 4-way tool post to the surface that the lathe tools rest on?

[not done it yetParticipant @notdoneityet]

It is a fairly minor job to replace/extend that existing threaded part. Best done with an operational lathe, mind. That old stud reminds me of lug studs for fitting wheels to vehicles.

[File HandleParticipant @filehandle]

I know it is now irrelevant in this case, but as anyone tried using LH drills to remove stuck screws?

[not done it yetParticipant @notdoneityet]

Posted by Keith Wyles on 30/07/2023 14:29:07:

I know it is now irrelevant in this case, but as anyone tried using LH drills to remove stuck screws?

Not always first choice, but is, for sure, for anything broken off flush and stuck.

Not a chance of trying cheap chinese ‘easy-outs’! They are only good for loose screws or the bin.🙂

[Howard LewisParticipant @howardlewis46836]

Margaret,

You have two PMs. Look for the flashing envelope at the top of the screen

[Margaret TrelawnyParticipant @margarettrelawny34058]

Howard

replied to your dm’s. Thank you.

Jason, I’ll check the measurements you suggested tomorrow.

Thanks

[Margaret TrelawnyParticipant @margarettrelawny34058]

Jason

do these photos help at all?

 

Edited By JasonB on 30/07/2023 20:46:37

[Margaret TrelawnyParticipant @margarettrelawny34058]

Not done it yet – I will be returning the ‘easy outs’ 👍😉

[JasonBModerator @jasonb]

Let me know the two shown

Edited By JasonB on 30/07/2023 20:48:45

[Margaret TrelawnyParticipant @margarettrelawny34058]

Jason:

[JasonBModerator @jasonb]

Thanks for those Margret, Both the QCTP you have and the 111 would work with larger tooling but the 000 may not suit the smaller sizes. To check exactly what works could you put something pointe din the lathe chuck or tailstock and take the measurement from that to the top surface of the top slide as below

Also if you could measure the diameter of the threaded portion of your toolpost stud that would help deciding what's the best way to modify that. I suspect it's an M8 thread so should be 8mm or a bit under.

[Howard LewisParticipant @howardlewis46836]

As jason says, the thread on the original toolpost "bolt" is probably M8, while the new stud for the QCTP may be M10.

IF long enough the "bolt", having a 10 mm shank, wsould be useable with a new washer, Top Hat or conical, with the QCTP.

The damaged csk screws can be replaced by ordinary csk Allen screws. No need to anything different.

Howard

[Margaret TrelawnyParticipant @margarettrelawny34058]

Hello chaps,

sorry for my late responses but I am at work.

I am awaiting responses from arceuro and Amadeal.

Jason – putting the tool in and offering up to a workpiece looks fine – although I did have to adjust the tool holder up a little (not sure if this is normal practice as i have nothing to compare against) – but a standard tool of the size I generally use does reach the work piece ok. See pic. I will try the stud later when home tonight but it looks likely that the stud will work or worst case, I need a new stud. The threads on the original stud look a bit worn don’t they?

 

i’ll send dimensions of the stud later when home and reply to all the pm’s.

 

thanks all

M

 

Edited By JasonB on 31/07/2023 11:26:56

[JasonBModerator @jasonb]

Thanks Margret.

Looking at the first photo the tool does not look like it is not yet lined up with the ctr of what you have in the chuck so could do with going up maybe another 2mm. This will put you right at the limit for that height of tool (10mm? ) and anything smaller won't really come upto ctr height without being packed up. So I would be more likely to opt for the 111 toolpost with standard holders so smaller tooling can be used. (hope the bottom ring is screwed on in that photo)

The other advantage of the 111 is the hole in the middle of the toolpost is 14mm which would be better to allow the existing stud to be retained and a shouldered nut made.

[Margaret TrelawnyParticipant @margarettrelawny34058]

Hello chaps,

sorry for my late responses but I am at work.

I am awaiting responses from arceuro and Amadeal.

Jason – putting the tool in and offering up to a workpiece looks fine – although I did have to adjust the tool holder up a little (not sure if this is normal practice as i have nothing to compare against) – but a standard tool of the size I generally use does reach the work piece ok. See pics. Although I am concerned how far I have had to adjust it. There doesn’t seem to be much thread left on the adjuster- is this normal?

I will try the stud later when home tonight but it looks likely that the stud will work or worst case, I need a new stud. The threads on the original stud look a bit worn don’t they?

i’ll send dimensions of the stud later when home and reply to all the pm’s.

thanks all

M

[Margaret TrelawnyParticipant @margarettrelawny34058]

Hi Jason, just read your latest response during a break (lol). Yes I think you may be right, it does seem quite near the extremity of it's adjustment – I think the 111 might be a better option. See pics below, they show clearly how near it is to the limit of adjustment.

Do you agree?

How I would make a shouldered nut though, I have no idea!

[Margaret TrelawnyParticipant @margarettrelawny34058]

I have just asked my brother to measure the distance from the top of the top slide to the centre of the workpiece/chuck – it is 20mm.

Does that help in anyway? Looking at arceuro's spec, I can't make head nor tail of which QCTP is the correct one for this!

[JasonBModerator @jasonb]

That sounds a bit low to me, from the photos I would put it closer to 25-28mm maybe check again when you are home.

The tool opening in a holder is 13mm so your tool looks to be about 10mm square. Max height of the bottom of the holder is 17mm but your adjuster is a couple of mm from max so lets say 15mm. so add the 15mm and 10mm and the edge of your tool is 25mm from topslide surface.

As for the nut well it only needs to be hexagonal if you want an extra spanner to loose. Simpler to go with something like you have that is cylindrical with either a fixed tommybar or just a hole for one. You could use the washer that comes with the toolpost then it is just a case of turning one end of some say 25mm bar down until it fits inside the toolpost and threading that end to suit the stud assume M8. Last thing is a hole for the tommy bar.

Not far off what I use on mine, the hole is drilled so I can use the chuck key to tighten the "nut"

the larger 14mm hole in the 111 toolpost gives a decent amount of metal around the M8 thread that you would not get if it had to fit the 10mm hole of the 000 size

[Margaret TrelawnyParticipant @margarettrelawny34058]

Hi Jason,

Thanks, I'll check the measurement when I get home. That is a nice QCTP you have on your machine, where is that from please? Would it fit my machine do you think?

Many thanks

Margaret

[Margaret TrelawnyParticipant @margarettrelawny34058]

Hi everyone,

OK, I have come to a decision. It's been a day of lots of conversations and to-ing and fro-ing. I have been overwhelmed by the helpfulness of Ian at Arceurotrade but the long and short is, I am reverting back to my original 4-post tool holder.

The QCTP has defeated me and being honest, my abilities are not sufficient enough to make a stud (or even Jason's suggestion of a shouldered nut). Kind offers from you gentlemen have humbled me, but realistically, I don't use the lathe enough yet to warrant going to all the effort to get one made.

Thank you all for your support and effort. It's been quite a weekend of broken screws, drilling, tapping and generally messing about with something which I had hoped would be an easy conversion.

But that's it, in a nutshell. It's not the end of the world. It's a learning curve and I may revisit this in the future if I find I am using the lathe more and more.

Again, thank you all.

M

[Margaret TrelawnyParticipant @margarettrelawny34058]

Although the decision has been made – like any good government does – I may do a U-turn lol. I ‘may’ swap the 000 for a 111 anyway and keep it for a rainy day when I have more experience. Although it will present the same issue with the rogue stud, it will at least be more suitable for smaller tools and not need the extreme adjustment position them as the 000 need.

Jason – you were right about the measurement. Somebody (who shall remain nameless) didn’t do it correctly – it’s 22mm. Does that help in anyway?

[Margaret TrelawnyParticipant @margarettrelawny34058]

Ps: it could be more than 22mm Jason but my topslide is not bolted together at the moment while I await those new screws.

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