Busm & Pearson Hm6 Needle Clamp Screws Size/system

[gordond]

Hi all

in conversation with Constabulary about needle clamp screws for the BUSM HM6- what screw system are they?

none of mine line up with BSW [or BSF] or any other system..

I believe Al has been through this before and ordered some offshore - but they didn't fit?

just putting this out in the public domain 'cause no doubt; it will be asked again [unless it has been already!]

[amuckart]

AFAIK all the screws in the BUSM machines are BSW. I have a mate who go,unreels at MOTAT who has access to all kinds of thread guages. If you want to send me one I can get him to measure it.

[gordond]

Thanks Al - will send you one that is "intact"--

we put 3 screws over all our gauges at work and no match on common BSW...

thought they might be a very old BA system- but we don't have a gauge

here is one that has been stretched and basically cross threaded

Edited April 18, 2015 by gordond

[Constabulary]

Any new insights on this topic?

[gordond]

sorry taken so long to get this sorted ...I took out the screws out of 4 machines and took them to work to size before sending to Al.

but they are all different !@!.an array of retapped metric [4mm] ,maybe Whitworth and munched up odd screws...everything from 3.5 - 4mm

Conclusion: ?? -without knowing if they have been altered - it's really a best guess to fit something

[not the answer we were looking for but if this is the state of affairs[altered] - then ordering an "original" is going to be hit and miss with these antique machines]

[Constabulary]

I´m about getting 2 new (hopefully original) screws. If they don´t work I´ll tap a 1 size bigger metric thread.

[Singermania]

HI All, I managed to get off the shelf ones that fit, the people that bought the Canadian ones found they don't....