Source for 1-1/4" x 8tpi nuts

[Woodmonkey]

In his video on my vacuum chuck thread Bob shows his home made face plates with wood threads, he used "hard maple"

 

[Phil Pascoe]

:idea: You could soak the threads with wood hardener as sold for decaying wood, then wax. That could give a quite hard thread.

 

[gregmcateer]

This is getting excitinger and excitinger!

Would you suggest making wooden 'nuts' with the wood in faceplate or spindle orientation?

An should they probably be 'long' - ie when done up, go right to the back of the spindle?

TIA

Greg

 

[jpt]

An easier way is to buy a spindle tap, http://www.toolpost.co.uk/pages/Chucks_ ... SpindleTap

They are no good for heavy work but then neither is the method you were thinking off, best £15 I have ever spent on a lathe tool.
John

 

[Woodmonkey]

Aren't they they same as what JG linked to in earlier post?

 

[bobham]

I use the Beall spindle tap for most of my vacuum chucks. It works very well and I have found that threads cut in hardwood seem to be quite durable. I usually make a hardwood disk which gets bored and tapped and then mount a disk of melamine coated particle board to the face of it for sticking my gasket material to. I did do a couple of videos on using the spindle tap. This series shows using it in end grain: https://www.youtube.com/playlist?list=P ... BB9F975C89

This video shows making a small chuck for my outside lathe using the 1" x 8 tpi version of the tap: https://www.youtube.com/watch?v=qm5GTFUQsy4

The best threads can be made in the fine grained woods like maple, cherry, birch, etc. Coarse grained woods like oak and ash may not thread as well, although I have done it successfully in a pinch. I actually have one chuck that is made from a pine disk threaded for my spindle.

Take care
Bob

 

[jpt]

Aren't they they same as what JG linked to in earlier post?

I missed that one sorry yes same thing different make.

john

 

[J-G]

Aren't they they same as what JG linked to in earlier post?

Pretty much - the difference is that from The Toolpost they are short - only 4 full threads - and cost £24.86 inc VAT & Carriage whereas from RDG they are full length (about 15 full threads) and cost £23.40 delivered.

 

[Spindle]

Would you suggest making wooden 'nuts' with the wood in faceplate or spindle orientation?

Hi

I'd go for faceplate orientation - top hat section let into disc to form a face plate:

Regards Mick

 

[Woodmonkey]

It's suggested on the site selling the taps that laminating a few layers of hardwood together with alternating grain direction will produce the strongest thread.

 

[bobham]

The instructions with the Beall spindle tap recommend only tapping face grain. Tapping into end grain will not yield as strong a thread, and depending on the wood may not yield any threads at all. I reinforce my threads with thin CA glue after cutting the treads and then run the tap in one more time to cut away any excess glue. Seasonal wood movement may make the treads quite tight on the spindle as the seasons change but running the tap through them again if they tighten up eases the fit again.

I can't see any reason to make the faceplate using the "top hat" configuration suggested above. I bore and tap a hardwood disk and then glue and screw a plywood, mdf, or melamine disk directly to the face of it after truing it up.

Good Luck!
Bob

 

[gregmcateer]

Bob, Mick, J-G et al,

Many thanks for all the time you have taken explaining the niceties of this. I really appreciate your knowledge and generous sharing of it - and I am sure WoodMonkey does too. I was beginning to add up the costs of all the faceplates, etc I was going to have to buy and getting cold feet. Now I know it's possible to self-tap, it's a go-er.

Cheers,

Greg

 

[gregmcateer]

Sorry to be a pain again, but should the tapped hardwood be 'long' - ie when done up, go right to the back of the spindle?

TIA

Greg

 

[Woodmonkey]

Just noticed that the tap wrench on jg's site to hold that size tap is over £40! Is there another cheaper way of holding it? Pair of mole grips?

 

[CHJ]

Just noticed that the tap wrench on jg's site to hold that size tap is over £40! Is there another cheaper way of holding it? Pair of mole grips?

Make your own, only need to file a square hole in a metal bar or even some good hardwood for that matter.

 

[J-G]

Just noticed that the tap wrench on jg's site to hold that size tap is over £40! Is there another cheaper way of holding it? Pair of mole grips?

Ahhh !

Since I have all the basic engineering hand tools already, it didn't occur to me that you might need a wrench

In all probability you could use a spanner (or two) if you have them - but as CHJ suggests make a wrench from a hardwood off-cut, or probably better still, two 150mm lengths of 10mm square steel bar with two screws (one each side of the tap). The amount of torque needed to cut this thread will be relatively low so the strength of the cast steel body isn't needed.

I would concur that cutting into end-grain is a no-no and the idea of 'layering' three thicknesses is very good. I would definitely make the 'nut' long enough to reach the back of the lathe nose.

JG

 

[Woodmonkey]

Ok thanks chaps, you are a useful bunch

 

[Duncan A]

Sorry, going off thread here slightly.. In case anyone is considering a similar project with a M33 x 3.5mm lathe, it is worth noting that a nut of this size should be relatively easy to source as M33 x 3.5 is a standard Metric Coarse thread. In fact, a similar discussion to this one was on the AWGB forum almost exactly two years ago, but looking for M33 x 3.5mm nuts. (not sure if I'm allowed to post a link).

sterlingbolt.co.uk may well do them, but I can't see their website properly at the moment, so can't be sure.

Duncan

 

[gregmcateer]

Ok thanks chaps, you are a useful bunch

Ditto to that! =D>

 

[bobham]

Hi:
For tapping the hole you need to have the tap aligned exactly with the hole. The easiest way to do that that I know of is to mount the wood on the lathe, bore the hole using a Jacobs chuck in the tailstock, then switch back to your live center and seat the point of the live center in the dimple in the end of the tap with the cutting end of the tap started in the hole. Lock the headstock spindle of the lathe so the workpiece can't rotate and then use any wrench that will fit the squared section of the tap (a crescent wrench works well) to turn the tap into the hole, cranking in on the tailstock ram at the same time to keep the point engaged in the dimple which keeps the tap aligned with the hole. When I want to back the tap out of the hole I usually just unlock the tailstock so it can be pushed back along the lathe bed as the tap threads out. It is unlikely that the tailstock ram thread is anywhere close to the same as the thread you are cutting, so it would be extremely difficult to co-ordinate backing out the ram and backing out the tap while keeping the center point engaged. In the video I linked to I moved the tailstock away when I was backing the tap out, but that is not really a very good practice since it would be easy to mess up the threads while backing the tap out.

Greg, yes, you want the wood to thread completely on and seat against the shoulder at the base of the spindle thread since that is what squares it up, just like chucks and faceplates. In most cases that means you need to cut a relief at the hole entrance since most spindles won't be threaded all the way to the shoulder. At the same time I am cutting the relief I also square up the face of the threaded piece and take away material from the outer areas of the face that might rub against the front of the headstock, leaving a raised boss around the threaded hole 1/4" to 3/8" wide to seat on the spindle shoulder.

Take care
Bob