Leg Threads

[Chris_Sav]

More from the mine of useless information!

I  have always thought that the older fatter leg thread on a Jelks table was 3½ TPI on an inch and three eighths post. The newer thread being 4 TPI on an inch and a quarter post.

Well I have the Market Inn table at home, removed because of the landlord enforcing strict social distancing. It's the older round leg and has thread damage where it was dragged around the pub by a band.

Looking on FleaBay, to my amazement, I saw a 3½ TPI RH thread internal (will do both) chaser (That's a first for me). So I thought I would grab that and did.

The chaser duly arrived and I offered it up to the thread on a damaged leg from the Market table. To my amazement it did not quite match! Out came the expensive digital caliper (yes should have done that before) and the thread appears to be metric! 35.00 mm post and a 7.0 mm pitch thread. It equates to approximately three and two thirds TPI.

I suppose that might not be imperial due to Jelks copying French tables when they started producing bar billiards tables or was it just the accuracy of the thread cutter?

The newer thread varies from light oak octagonal tp later mahogany octagonal tables. Mahogany tables are 4 TPI on an approx 32.50mm post. The light oak thread is slightly tighter with eight threads take 1.96 inches. I think one size socket would fit all 4TPI but am only 90% certain.

Ah well! back to the drawing board on finding a 3½ TPI thread cutter. I may have to repost which I don't want to do.

[dillon]

I'm still looking for a solution to my mostly knackered threads on my otherwise lovely Jelkes table. Males and females both knackered! Isn't there a metal insert solution yet?

[Chris_Sav]

The only time I dealt with a serious one before I had a spare post and reposted the leg

Other than that I have found gluing the female dowels back together and/or rebuilding the male thread with epoxy and a file has worked well enough.

Metal is not thought a good way as attaching the rod to the leg permanently is problematic with it pulling out unless you cut a hole in the leg and insert a nut and that is messy.

I'm having a look at the problem fairly obviously as the female dowel is too buggered but won't be rushing. Got very close to making the female part out of aluminium but the screw threading on the lathe was not man enough.

[Chris]

I believe AEBBA purchased a set of thread cutters to Dave Adler ?

Seems silly to get anymore.

Not sure where they are ?

And maybe I have no idea what I am talking about and they were something else..?

But I know they dealt with threads on legs and inserts.

Chris

[Chris_Sav]

Denis Atkins helped with a mould to reform the male 4TPI threads.

AEBBA bought a thread cutter from the States but a smaller diameter, not fitting either of the existing threads. That has the advantage of leaving thicker walls on the sockets but complicates table set-up and risk of cross threading, Matt J. has the cutter last I heard 

Fine Tools in Germany do the 4TPI cutter principally found on octagonal legged tables.

I don't think 3D printing of the sockets would be as easy as the rings as it's difficult to photograph and scan a picture of a hole!

I'm making enquiries in the lathe world but it's difficult during social distancing. I feel rigid plastics or aluminium could be a better way forward for the fragile female sockets.

[daveuk1]

If you have something to use as a template I'm sure my son could knock up some carbon fibre bits

[alanturner]

Aug 13, 2020 8:07:23 GMT Chris_Sav said:

Denis Atkins helped with a mould to reform the male 4TPI threads.

AEBBA bought a thread cutter from the States but a smaller diameter, not fitting either of the existing threads. That has the advantage of leaving thicker walls on the sockets but complicates table set-up and risk of cross threading, Matt J. has the cutter last I heard 

Fine Tools in Germany do the 4TPI cutter principally found on octagonal legged tables.

I don't think 3D printing of the sockets would be as easy as the rings as it's difficult to photograph and scan a picture of a hole!

I'm making enquiries in the lathe world but it's difficult during social distancing. I feel rigid plastics or aluminium could be a better way forward for the fragile female sockets.

WIXROYD INSERTS  

Order No.34693.W0724

d1      M24

d2      56,5

d        360

h        150

h        212

Max. static load kN10,0

See full product selection


 4 = APPROX £28.00  PLUS M24 THREADED BZP £12.00 "ISH" PLUS CHEMICAL EPOXY

[Chris_Sav]

Aug 13, 2020 17:30:34 GMT daveuk1 said:

If you have something to use as a template I'm sure my son could knock up some carbon fibre bits

I'll email a picture and if it looks possible I cost send up an insert.

Better still ferry up an insert for close examination, possibly over a pint

[Chris_Sav]

Re Wixroyd I have used their stuff before, lift hinges for Jelks scoreboards and found hinges for bars as well.

Have you tried posting with threaded  bar Alan?

[Chris_Sav]

Alan Mee has kindly supplied some thread offcuts of the older thread and we are going to have a go at moulding inserts

[Chris_Sav]

Unfortunately the male half of the thread is once again different.

Back to the drawing board.

[alanturner]

M24 Inserts took ages to arrive , but when they did brilliant , so today...............bonded them and the studs in with resin.......... Success ( I think , going away for a few days..........further up north , so resin will have cured when i return )


 THESE INSERTS AR CRAP , WHEN YOU TIGHTEN THE LEG INTO PLACE IT PULLS THEINSERT OUT OF THE RESIN/POLY SURROUND ...........................

[alanturner]

Sept 14, 2020 20:22:20 GMT alanturner said:

M24 Inserts took ages to arrive , but when they did brilliant , so today...............bonded them and the studs in with resin.......... Success ( I think , going away for a few days..........further up north , so resin will have cured when i return )

Photos 3 and 4

[Dave J]

A number of people have asked if its possible I could make the threaded leg inserts and posts.

36mm x 7mm pitch (90 degree thread form). I also did a plastic post just as a trial.

I can also make the 4TPI version.

The other one I was asked about was the feet so here's a couple I knocked up.

[Dave J]

First set of legs repaired with 1" 1/4 x 4 TPI

[Chris_Sav]

Bit late for me now unfortunately, but nice work Dave