Help with air tool thingy

[brianhabby]

Hi everyone,

I have an air nailer that says it uses a ¼" thread on the bit that screws into it to connect the air hose to. However, when I measure the actual device, the thread is anything but ¼" more like a half inch. (see photo)

Looking in a catalogue gives me two sizes for this screw adapter ¼" and ⅜" but I'm not sure which one to order. Why does the instructions call it a ¼" thread when it actually measures more like double that?

I'm confused :?

Also does anyone know of a good book about all things compressor related - this stuff seems complicated what with all the different fittings etc that are available? I'd also like to understand how to maintain the compressor properly.

Any help on this would be much appreciated.

regards

Brian

 

[MooreToolsPlease]

Those are the same fittings as mine, I just ordered some fittings from Axminster, they were all 1.4" BSP fittings if I recall

 

[oddsocks]

the thread is 1/4" BSP as are most. You can get different diameter hoses but typically they all end up in the same size fitting (i assume the bigger ones -8mm - have faster flow).

look at this link for connectors http://www.sealey.co.uk/PLPageBuilder.a ... results=10

Also, a good page i found some years ago when looking for similar info is this one
http://www.diy-compressors.com/spraying-painting.htm
gives relevant practical advice

I would advise fitting a lever controlled connector at the compressor end - makes it safer to remove tools as you can discharge the air in the hose

 

[mailee]

Yes that looks like the item you require Brian. It is named : 1/4" male PCL fitting. This type screws into the base of your nail gun, Why it states 1/4" thread I have no idea but it refers to the actual fitting at the airline end which is actually 1/4"BSP. There is also a 3/8" type too but they are for larger airline. Not too sure where you will get a book from but a trip to your local compressor sales shop would be of help to you. The only maintenance of your compressor would be change the oil regularly and keep the air filters clean and always put a few drops of oil into the airline end of the gun after each session. Air tool oil that is which is thinner than the stuff used in the compressor. :wink: Oops! Almost forgot, make sure you drain the water from inside the compressor reciever each week too. :wink:

 

[Travis Byrne]

Hi Brian

On tapered threads like the one you have pictured(called pipe threads over here), They measure the internal dia. Check and see if the hole in the the part is 1/4 inch.

Travis

 

[9fingers]

Hi Brian,

BSP (British Standard Pipe) threads are steeped in history and are based on the thread cut on a pipe of a certain bore. As manufacturing technology for pipe has improved the OD has stayed the same to make the thread work but the wall thickness need to meet the specification for pressure has reduced to make the pipe cheaper. Often there will be no dimension of modern pipe that equates to the nominal thread size.
Transfer such a thread to the context of an adaptor or fitting and as you have found, dimensional confusion reigns.

HTH

Bob

BSP is common almost world wide apart from US where they have a slightly different thread pitch and form known as NPT (National Pipe Taper). These look very similar to the uncalibrated eye but will not interchange with BSP

 

[brianhabby]

Thanks for your help guys,

I'll order one of the ¼" ones based on the comments above. At least then I'll know for sure next time.

Incidentally, I've just measure the inside diameter of the part and it is nearer 5/16 to 3/8.

regards

Brian