Hand threading - spindle speed?

[Matj16]

Hi all,

New to the forum and equally looking to buy a first lathe. I have already decided what im buying but had a little query.

My experience in woodworking comes largely from my education. i spent as many hours as possible in the workshop and was privileged to have full size lathes, band saws etc at my disposal. I recall that for hand threading, which is something i intend to do on my new lathe, slower rpm's are vital to ensure the thread is not stripped. In your experience is 500rpm slow enough to achieve this?

I am conscious on buying a lathe with the ability to run at slow enough speeds for threading successfully but want as much budget available as possible to invest in a decent grinder, chisels, safety gear etc etc. I am fully expecting the accompanying items to cost as much if not more than the lathe.

I will be buying from axminster so will have the benefit of visitting a brick and mortar store but an awareness of how much money im expecting to part with when i leave will be very useful!

Thank you in advance.

 

[Alpha-Dave]

I thread at 280-320 rpm. I have only made ~20 threaded boxes so this is not gospel.

John Barclay is my reference for threading, his books and DVD are very good in my opinion.

Try practicing on a soft plastic first to learn the ‘feel’ for the movement and speeds. My tutor recommended knitting needles.

 

[Matj16]

Thanks for your response dave. Around the 300 rpm mark is what i thought as well. Leaves me a tough decision as the lathe i wanted will go down to 500rpm but no lower whereas its slightly bigger brother will go much lower but at the expense of another £170 which i wanted to put to better use.

May be the case that i get them to demonstrate on both before buying. If they know they will get the sale either way im hopeful they will accommodate the request.

I will actually mainly be working with acrylics and resin so the materials i will be using will be relatively "soft". May use woods at some point but no immediate plans.

 

[loftyhermes]

The slowest speed of my lathe, a Record DML24 is 450 rpm, I've learnt to hand chase threads at this speed.

 

[Matj16]

I will have the same problem. Slowest will be 500 rpm unless i go for the more expensive model however the rpm benefit is in essence the only benefit i will get from the more expensive model. Having said that it will impact on almost every project i make...
Will mull it over. Im in no rush to buy it.

 

[marcros]

What is the budget and what capacity do you need?

 

[Robbo3]

Even John Barclay admits (as a practicality) that you can hand chase threads at 750 rpm, as many have had to do, because that's their lathes lowest speed. Just means you have to quicken the hand speed to match & be pretty deft at removing the chaser before it hits the end.

 

[Matj16]

Thank you for your responses all. Although im not new to using lathes for larger projects im much less experienced on smaller items. I had hoped to keep the post away from a "which lathe discussion" as im sure you get plenty of them but i do appreciate the valuable advice on hand chasing.

In terms of budget i was hoping to stick at 300ish and was going with the axminster hobby range. That was until i realised its lowest speed was 500rpm which made me consider its bigger brother at £500 which will go substantially slower which will make hand chasing easier. My main purpose is to be making kitless fountain pens as im somewhat bored of spending £150+ on every pen i buy when i could make them myself out of much nicer materials.

If im honest i would rather spend £300 but i am conscious that i will benefit from the lower rpm and therefore tempted to buy the more expensive model.

In terms of capacity... 8 inches in length with a diameter of 1 inch. I dont need a big lathe at all and equally do not have enough space for a freestanding lathe. Thats not to say my projects may not grow in size later so im erring on the side of caution and looking to get a lathe i shouldnt outgrow anytime soon.

 

[Alpha-Dave]

Having spent a short time looking into this, I came to the conclusion that for kitless pens you will want to make a triple start to the thread. You can either buy triple start taps at £100-£200 each or use an engineering lathe with a geared headstock.

http://www.beaufortink.co.uk/3leadtapsanddies.html

 

[Inspector]

I've made a few kit-less pens on the metal lathe and used triple start taps and dies. I hope the 8" capacity is the working length after you take account of the chucks and drill bits etc.

There are pen makers in Japan and India that hand chase multi start threads for their pens. There is nothing wrong with single start threads on a pen as long as you keep them from being too long. Most people want to get the cap off in a couple turns and not half a dozen. Upside to them is that the pattern in the material can be aligned when capped instead of only from one start position.

https://www.youtube.com/watch?v=08pUuLREZR4
https://www.youtube.com/watch?v=1F12qUyIACM
https://www.youtube.com/watch?v=SByOoh2XK6c

Pete

 

[marcros]

Probably off topic, but for the kitkess pens I have done (a few) I thread with taps and dies. The triple thread cap thread is not one that I have, so I use a single start die. M12*0.75 or M14".75 I think, generally the smaller. The triple thread is nice but not essential, and with a single start thread the pattern is guaranteed to match up. Horses for courses.

 

[Happy amateur]

Anybody thinking of doing kitless pens I would suggest you have a look at youtube maker rjbwoodturner who has several videos on starting and making kitless pens
https://www.youtube.com/user/RJBWoodTurner

Fred Taylor
orchard-woodturners.org.uk

 

[Matj16]

Thank you all for your input.

Inspector the 8 inch comment was what i need from a machine. In reality the lathe i intend to buy is over 17 inch with the ability to buy an extention if i ever wanted it. This should ensure i have more than sufficient capacity for whatever i decide to do with it.

I have considered the 3 vs 1 thread argument and can see the merits of a three thread approach but for me the cost outweighs the benefit. The vast majority of pens i own (ranging from £30 to £150+) all use single threads. I have seen a few videos whereby pen makers hand chase a triple thread however i wish to keep my sanity and not spend all my time cursing or ruining blanks.

The masters of japan video series is amazing not only in terms if the work they produce but the basic tools they actually use. I have seen the vast majority of the youtube videos already.

I will have a more thorough look through rjb. I have seen some but not many of his videos.

Thanks for all your help.