Thread pitch

[pgrbffParticipant @pgrbff]

I recently bought an old chandalier. The candle(light) holders are threaded but a standard M10x1.0 nut would not fit. I bought a pitch gauge and they measure 0.9mm pitch. I cant find any refere nce to M10 x 0.9 pitch, nuts, tap or dies. Is this a size that may have been produced at some time?

Where might I found some nuts?

Should point out it is most likely an Italian chanadalier.

[pgrbffParticipant @pgrbff]

[Michael GilliganParticipant @michaelgilligan61133]

25.4 ÷ 0.9 = 28.2222

and the old 1BA thread pitch was nominally 28.2 tpi

It is, of course, common practice to use convenient fine threads on "tubes".

Looks like you have a standard UK fitting there; so just look for an Electrician with some old stock.

MichaelG.

[pgrbffParticipant @pgrbff]

Thank you for the quick reply. As I understand it 1BA is around 5.3mm diameter. Is it possible for me to find a nut with 1BA pitch that will fit a nominally 10mm tube?

[JasonBModerator @jasonb]

3/8 x 28tpi brass thread was a standard electrical thread.

Could also be 1/8 BSP which is 28 tip and just over 3/8"  OD

J

Edited By JasonB on 25/09/2012 22:10:00

Edited By JasonB on 25/09/2012 22:25:33

[John Stevenson 1Participant @johnstevenson1]

I'll go with Jason.

Used to make some light fittings and these were, as Jason says 3/8" x 28.

[Michael GilliganParticipant @michaelgilligan61133]

Agreed

and, as I said; friendly local Electrical shop is the place to look.

… failing that, it's a good excuse to poke around the Car Boot Sales.

MichaelG.

[pgrbffParticipant @pgrbff]

Thanks for all your replies. May not be so easy to find 3/8 28tpi here in Venice, but I may be wrong. I don't have the thread with me but I think it measured about 9.7mm OD, I guess this would be about right for threaded 3/8 rod?

I may have to look online.

Sorry I didn't pick up on the replies last night but the notifications went to spam for some reason.

[pgrbffParticipant @pgrbff]

Found one nut in electrical shop, 5 to go.

[pgrbffParticipant @pgrbff]

1/8 BSP, bought myself a tap and re threaded the fittings. Thanks for the help.

[mickParticipant @mick65121]

When I was involved with the manufacture of light fittings the lengths of threaded tube were known as "all thread" which is M10 x1.0

[pgrbffParticipant @pgrbff]

Current fittings are M10 x 1.0 but I jave found several older pices which were 1/8 BSP.

[Speedy Builder5Participant @speedybuilder5]

Uh – thought model engineers screwcut things like nuts !

[Author]

Posts