M 1.4 threaded steel rod

I've been asked to source a few feet of 1.4 mm diameter grooved steel rod. For all practical purposes the size and groove depth match M 1.4 thread so some threaded rod will do just fine.

I can only find it in short lengths of brass which won't do. Does anyone know of a source in steel?

If not is it practical to make my own. Tracey tools can supply a die, E-Bay also offers a thread rolling head at a not impossible cost, but what material to use and where to get it from. Common piano wire will clearly be far too hard to thread.

I imagine stopping something that slender from twisting during the threading process will require care and creativity.

Thanks

Clive

I would have thought that thread rolling is the way to go, much stronger and no swarf to clear when doing long lengths. finding material of the right dia might be harder as you need material smaller than 1.4mm. As far as the material twisting I would have thought that the torque to do the thread rolling is relative to the size after all you will not be the first person to make some.

Try somewhere like radios spares.

I used to buy a lot of screws and studding fromJML.

Also a clockmakers supplier like Shesto.

Found it on EBay but steel might be out of stock. Available in brass though.

M1.4 Allen screws are available but may be to short for your use.

To cut the slots in steel, you might be able to use a dremel elastic wheel.

Just bought some M2 studding but nothing smaller available. I found few places went below M3.

If stuck for finding a material to make your own from then I offer the suggestion of Kirschner wires - surgical stainless steel used (usually) as temporary pins in bone reconstruction or for attaching small fragments. Available in lengths upto about 300mmm but with one or both ends sharpened usually as spade ended.
I did see some on eBay in sizes near to your need - 1.2mm and 1.4mm were available but I’m sure an orthopaedic supplier would stock 1.3mm ("veterinary instrumentation" as an example)

Edit - for some reason my brain read that you wanted 1.3mm until I posted and reviewed the title

pgk

Edited By pgk pgk on 01/04/2022 22:16:39

I think this place may stock it. www.component-shop.co.uk It's quite a while since i bought from them, but they had some at one of the shows i went to.

Dek.

Thanks for the advice gentlemen.

It's for something to do with renovating a harpsichord. The grooves that are important to retain the parts in wood so it doesn't need to be a screw in thread. The pieces need to be straight too, the ones that came out certainly aren't. I found the M2 studding last year. Acceptable then but considered oversize now the man comes to do the job.

After further searching it looks like 1.4 mm steel rod can be got from Hobby Holidays at about 50 pence a foot so I'll probably go with that. Tracy Tools have dies at £18 each so sticker shock shouldn't give him a heart attack.

Thread depth is 0.15 mm so I guess I'd need 1.25 mm steel rod to start with which seems pretty unlikely. Translates to 0.049" which is near enough 18 gauge (0.048" ) so thread rolling is possible if suitable material can be found.

No luck at component-shop, nearest kirschner wires from UK suppliers appear to be 1.2 mm which may not be enough to thread roll. Fascinating how much stuff I didn't know about can be found by asking here.

Clive

Edited By Clive Foster on 01/04/2022 22:36:19

If its for the harpsichord, they used short lengths about 3" long I seem to remember. I had to make a few many years ago in brass for a friend. I believe they were used for the connection between the keys and the "pluck". So apart from wastage, short lengths would be OK

Bob

1.4 mm is 0.055" in old money.

The nearest stock size would be 17 SWG, which is 0.056"

This ought to be available in soft iron wire.

The problem is likely to be that it might be supplied m,as a coil. In which case, the first job would be to straighten it; which probably means making a wire straightening tool!

Howard

The easiest way to straighten a length of wire is to hold it vertical with the top end gripped securely, with a weight attached to the bottom end heavy enough to make it straight, then to twist the weight in order to 'bend' it rotationally.

Reckon Speedy Builder5 is right about what this M 1.4 rod is for. Certainly looks so from the sample "fit to this" parts I have. Interesting that brass has been found acceptable before as my man says it has to be steel.

Trying hard not to be sucked deeper into this job. Big difference between half and hour or so on t'net to unearth a "get it from here" and deep involvement in making it. Straightening wire is definitely about 4 steps too far. Would soft wire even be stiff enough to thread?

Looks like options are:-

1) die cut thread using 1.4 mm rod from Hobby Holidays and a die from Tracy Tools

2) thread rolling head and 1.2 mm kirschner wires, both off E-Bay

Interestingly that E-Bay thread rolling head is for bicycle spokes but 18 gauge spokes don't seem to be made.

I'll see what he says.

Clive

Looking on Veterinary Instrumentation's site there's 1.25mm arthrodesis wire and 1.5mm threaded rod available.

https://veterinary-instrumentation.co.uk/catalog/product/view/id/6118/s/arthrodesis-wires-125mm-long/category/1094/

https://veterinary-instrumentation.co.uk/catalog/product/view/id/6129/s/fully-threaded-arthrodesis-wires/category/1108/

Without looking further I’d speculate that Imperial sizes are available from a US orthopaedic supplier or an Indian/Pakistani supplier who sells to the US. How accurate any of these dimensions are might need checking. Also the thread on arthrodesis wire will be designed for holding in bone - would likely be fine in a denser timber but also may not be 'standard' if wanting to use off the shelf nuts.

pgk

pgk pgk

Thanks for that. Looks like I do have an option for correct size to thread roll then.

1.5 mm fully threaded would be too large. Specific thread isn't important, its the grooves that matter as they help it hold in place.

Clive

I threaded a 100mm long piece of 1.3mm springy stainless with a 12BA die and had no problems.

Gary

Nice to know that such things go quite easily given reasonable care.

Clive

If the threads are only there to grip in wood would some type of knurling suffice?

Bernard

Very probably knurling would do fine but probably even harder to arrange than threads on that diameter.

Clive

I have seen small round bar semi knurled /roughed up by having the bar laying on apiece of timber and a bastard file laid on it and rolled along with good downward pressure. this was for an araldited joint in wood.