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Air tool threads

I recently bought a small compressor which has (appaently) 1/4" BSP fittings - I haven't measured them, just accepted what is in the manual (There is no mention of BSPT).

To compliment this I am now looking for various accessories - Simply blow gun, Tyre inflater etc.

Looking on eBay I see quite a few '18 piece' and '21 piece' sets and none of them specify what thread the fittings are. I've sent mesages to four different sellers and none came back with any answer until I sent a 'sort of' snotty message detailing a sentence from his eBay Shop text where he said that he was a caring and conscientious seller and asking for at least a 'Sod Off - I don't know'. To which he simply replied '??????????????'.

Eventually we did get into a conversation and he appologized for not knowing what I was talking about (My question was simply are the fittings NPT or BSP) and giving me details of the manufactureres web site.

No details were available there but there was a 'contact us' form so I sent them the same question. This is their response:-

"I am sorry that you were not able to get the appropriate answer from our online reseller.

To answer your question, they are ¼? NPT (Euro/US) couplers but all the threads are in fact BSPT as is all our air tool range."

Can anyone turn this into a definitive statement with regard to the thread on the fittings they make? Or correct my misunderstanding with respect to Air Tool fittings?

TIA.

JG

Reply to
JG
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1/4" BSP is 19tpi and 1/4" NPT is 18tpi, the diameters are about 20thou different. If the tools have adaptors fitted, then they could support both threads by removing the adaptor, or not. All of the tools I've got so far, over here, have been 1/4BSP even when of obviously Chinese origin.

None of that is very helpful :-( If the tools look to be a sufficient bargain, then get them and assume that you may have to get 1/4"NPT to PCL whip hoses if they don't have 1/4"BSP fittings.

Mark Rand RTFM

Reply to
Mark Rand

All air tools I've got have been 1/4" BSP, or at least the 1/4" BSP fittings have screwed in and sealed. Normally with air tool stuff, the female threads are straight, and the male threads are tapered, but I can't actually remember seeing any tool catalogues that mention that.

Reply to
moray

Hi JG, not my world I'm afraid but have a look here about half way down they discuss the fit and where they will leak if the two different sizes are assembled together:

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Like Mark says, if it is cheap enough and a good tool I would look to make up an adaptor hose. My cheap Chinese compressor came with 1/4BSP and an even cheaper set of "tools" from a market type stall fitted perfectly, but that could just have been my good luck of course.

Keith

Reply to
jontom_1uk

from Mark Rand

Thanks for the speedy responses. I didn't expect anything until at least tomorrow.

That is precisely why I am looking for a definitive statement from the manufacturer. The answer he came back with tells me that he is not the manufacturer at all (as you suggest - probably Chinese) and he has no idea that there is any difference. First he says they are 1/4" NPT and then contradicts that statement by saying they are BSPT.

That is something I hadn't considered - there are various connectors in the kit which may just be there to cover this problem.

They're on a B.I.N. @ £9.49 + £2.99 Postage so it's not a fortune - I would have expected anyone selling this type of equipment to know what he was doing though - another dream shattered :))

I will not be using this equipment on a regular daily basis to earn a living so I'm not looking to buy the best there is to las me a professional lifetime. Now I have a compressor (bought to drive a sand blasting cabinet) it simply makes sence to use it to blow swarf out of oily holes to save me getting a face-full.

JG

Reply to
JG

Every air tool I have bought (and that's quite a few, both cheapies and proper tools) has had a 1/4 bsp female thread.

Reply to
SimonJ

The only different threads on my air tools is die grinders with 1/8 bsp[or was that NPT} and 1/4 NPT on some spray guns.

Reply to
integerspin

If you're in the UK, have you had a look in the 'Machine Mart' catalogue, they do a huge range of air tools, pipes fiting and stuff for 1/4" BSP. I've had stuff from there before and its all been fine! OK its all imports (but isn't most everything these days? - including the 'quality' badged stuff you pay a premium for!) Tracy Tools down in Devon will sell you tapping drill & taps for a very modest price if you feel adventurous.

Regards Mike

Reply to
MikeH_QB

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