Member postings for Margaret Trelawny

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Edit: rotated photos.

Edited By SillyOldDuffer on 27/08/2023 14:13:56

Edited By SillyOldDuffer on 27/08/2023 14:14:41

Chatter 2

Morning everyone, my machining marks continue.

To recap:

1: I have checked the centre height of the tool - it looks apot on.

2: purchased a piece of CZ121

3: purchased the tool tips recommended from APT.

4: feeding the cross slide with both hands (which has helped).

But, although an improvement - I would say I am far from happy with the results so far. The facing off is better after the second pass, but the turning isn’t.

Any suggestions where I am now going wrong please?

Thanks everyone - super advice as always. Thank you for the pics and video - it really does help a learner. I have digested all the info (I think!) and it has given me new heart. I have purchased the silver inserts Jason linked (from APT) and some CZ121 bar to try. Will report back when I can.

Again, I cannot stress how valuable and helpful you all are. I very much appreciate your help.

M

Thanks Nigel

Thanks guys. Appreciate your help.

Jason - this is the tool - which of those inserts for non-ferrous would fit? I’m not familiar with the coding and how you match up inserts.

thank you!

Thanks Stuart. Could you recommend a tool I could purchase please? I am not experienced enough yet to grind things.

How can you tell when you buy brass whether it’s any good for machining? I just buy off ebay.

Could you enlighten me about the six inch ruler trick please?

many thanks

The tools should be sharp Jason - they are both fairly new and not used much. Would being the wrong height give those results?
I can purchase another tool and try that perhaps? Any recommendations for best brass turning tool? Just straight reduction work at this point.

many thanks

Sorry, just had to reply off hubby’s phone as mine died and realised it was signed in on his account! 🫣

My friends - HELP!
Not sure what is going on but I am getting excessive cutting marks - chatter!?

I love a good natter but not this chatter! It’s driving me mad! Everything seems to be tight: the cross slide and compound are tight but moving freely. The gib is tight(ish) on the compound. The tools are fairly new - carbide inserts and HSS are giving me the same results.

Any ideas please? The thinner brass stock is hopeless to turn - it’s bending when the tool is applied. Even facing is giving me rings!

The only tool which cuts without leaving marks is the parting blade. But that isn’t moving right to left.

I am so frustrated! (Using the original tool post from the lathe - as I can’t even begin to think about machining a new stud for the QCTP until I get this headache sorted.

Thanks

Very nice solution John - thanks for sharing.

Just watched a YouTube video where a chap had a problem

mounting a 111 due to the spindle being incorrect - so he drilled the supplied internal mounting bolt of the 111 and tapped it - then fitted it over his spindle. Seemed to work

well.

I do fancy a crack at the nut.

Would the stud need the serrated part - could it not just be machined to a tight fit?

Thanks Jason - great info.

Should I decide to have a crack at the stud, what material would you suggest? Mild steel? Did we say it was an M10 thread on the QCTP top? I can’t find the post with it on!

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

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?

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

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

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!

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!

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