Thread cutting

[boysie39]

I think this is what boysie was asking about
http://www.ebay.co.uk/itm/WOODTURNING-L ... 43ae6a89fe

Thats the one ,it looks to be an easier way to cut threads for boxes , I'm just not sure if it can be used for the inside threads as well.
My lathe has V/S fitted and can go from 0 to 3000 I've had it at 0 many times but havent got up to the top speed yet .
I have watched John Berkley ? many times but I know it's not as easy as he makes out to be .
The spindle thread on my lathe is 1"1/4 x 8 tpi and for some reason they need to know this . Has anyone used or seen it used , would it be worth buying .
Thanks for all the replys .

 

[Harlequin]

here u go boysie
Dunno if these can be got locally
http://www.youtube.com/watch?v=L1rel_WKFfw

 

[CHJ]

....The spindle thread on my lathe is 1"1/4 x 8 tpi and for some reason they need to know this . .......

That's so that you can use your existing chucks on it.

 

[Paul Hannaby]

Hi Eugene,
Get yourself a pair of thread chasers and give it a try! You'll be surprised how easy it is once you get the hang of it. If you want to borrow a pair to have a go, let me know.

 

[Robbo3]

John Berkley is a master of hand thread chasing. He recommends 16 TPI (Threads Per Inch) as the easiest for beginners & a speed of 400 RPM if your lathe will go that slow otherwise use 500 RPM or the lowest speed.
His home page, - https://sites.google.com/a/obxcompguy.c ... aintenance
& a video - http://www.youtube.com/watch?v=i73lWmUO9gQ

I agree with everything Ian (flh801978) said in his earlier post.

The Ebay jig works along the same lines as the Bonnie Klein jig & will cut both internal & external threads,
- http://www.bonnieklein.com/turning-prod ... eading-jig

Robbo

 

[jasonB]

A woodruff cutter won't work as there is no relief and the cutter won't follow the helix angle. Same as trying to screwcut a square thread on an engineering lathe without grinding clearance on the tool.

And 7/8x16 taps are available from about £12 not £30-70.

J

I said woodruff type (not form) and a small dia cutter will create its own threadform like a hob it is a common way to mill threads. The price I quoted was the price I had seen for Whitworth form threads UNF are much cheaper. Anyway enough of trying to be helpful after 50 years in Engineering I obviously learnt nothing apart from how to create argument. I'll stick to asking stupid questions rather than trying to help anyone. Obviously thats all I'm fit for practically every post I have made over the past few days has been picked on really not what I was looking for in a forum.

I was only pointing out that if the purchaser wanted to do smaller threads then taps can be had for less and they were whitworth form 55deg that I quoted, 7/8" x 16 is not available in UNF.

You don't seem to have grasped how this jig works because you said "if you are thinking of threading large diameters or long pieces then not of much use" because you thought it only cut the male thread, if you look closely at the picture on the e-bay advert & Robbo's B&K link you will see that the cutter is of the "woodruff type" you talk about so will indeed act much like a thread mill and will cut internal threads from 1" upwards. Again I only raised these points to correct the wrong information you were giving to the OP and you did say "that you may have got it wrong again" , think you did :wink:

J

 

[Frank S]

Morning, Jonzjob,
that looks an interesting piece of kit, any chance of a heads up on it ? I have the Record CL 2 lathe.
Frank.

 

[duncanh]

At least one of the members of the Northumberland club has one of these jigs bought off Ebay and commented that he really liked it and it worked every time. I've never seen it in person but he's a fairly experienced turner so should know what he's talking about.

 

[CHJ]

Here you go for some better images of a thread cutter made by Kym and Co. of this forum, the only difficult bit is locating the 60 deg cutter, not common and not cheap. To a purist the thread form may have a small margin of error due to the lack of cutter relief but as both internal and external threads are cut the same way they will match, and the error will be so slight anyway that it would probably be un-measurable on wood. A single point turning tool would be an alternate but would need a much higher headstock rpm to provide the same cutting performance.

 

[Wildman]

A woodruff cutter won't work as there is no relief and the cutter won't follow the helix angle. Same as trying to screwcut a square thread on an engineering lathe without grinding clearance on the tool.

And 7/8x16 taps are available from about £12 not £30-70.

J

I said woodruff type (not form) and a small dia cutter will create its own threadform like a hob it is a common way to mill threads. The price I quoted was the price I had seen for Whitworth form threads UNF are much cheaper. Anyway enough of trying to be helpful after 50 years in Engineering I obviously learnt nothing apart from how to create argument. I'll stick to asking stupid questions rather than trying to help anyone. Obviously thats all I'm fit for practically every post I have made over the past few days has been picked on really not what I was looking for in a forum.

I was only pointing out that if the purchaser wanted to do smaller threads then taps can be had for less and they were whitworth form 55deg that I quoted, 7/8" x 16 is not available in UNF.

You don't seem to have grasped how this jig works because you said "if you are thinking of threading large diameters or long pieces then not of much use" because you thought it only cut the male thread, if you look closely at the picture on the e-bay advert & Robbo's B&K link you will see that the cutter is of the "woodruff type" you talk about so will indeed act much like a thread mill and will cut internal threads from 1" upwards. Again I only raised these points to correct the wrong information you were giving to the OP and you did say "that you may have got it wrong again" , think you did :wink:

J

my apologies bad case of mad cow disease yesterday got me all riled up. the cutter shown above are easy to make and when I have time I'll make a batch to be offered on here. Lack of top relief is not a problem in wood I have used one before.

 

[jasonB]

J&L do the 60deg cutters but as you say not the cheapest with teh smallest 3/4" dia being £42 + VAT. Though the mini-mouldcutters from Weladen are a possibility if doing larger dia work

As Wildman says anyone with access to a lathe or friendly engineer could make one up from silversteel without too much problem.

J

 

[boysie39]

I made one of these

And for doing ths

I got one of these as well

http://www.axminster.co.uk/axminster-ax ... prod21303/

Hey Jonz, that looks a great bit of kit, I know an old turner that makes up his own jigs and things like that .We had a workshop at his place a couple of years back and he should how a carrage like yours could be used for threading and for mounting a router on and making grooves and spirals .
I've got a great responce to this thread and will give it my full attention and see which will suit me if any .
I may just do as Paul has suggested and try the hand chasers , although I hate the sight of blood
Off soon to the Hospital for a bit of proddin and pookin ,as I going to be in the Big Smoke I may just get a pair of them chasers .