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SteveHGraham wrote:To anyone else out there who has this problem, my advice is to turn an 18 TPI fitting with an OD of 0.505". It should screw right in.
I'm a little concerned about the internal diameter. I used a 1/4" bit, and that appears to be a little smaller than the original fitting, but I guess I can fix that later, and anyway, it will work fine for a blow gun and filling tires.
FYI, 1/4" schd 40 pipe has an ID of .364", schd 80, .302" ID.
Small compressor, short orifice....I doubt you'll notice.
Just because a part is made in China do not automatically assume it will be metric. I have a new Chinese lathe and the thread on the back of the spindle is Whitworth. I was told by the company I bought it from that this is common, in the early days they copied various countries lathes and thats what you end up with today, a mish mash.
And BSP is not NTP. It is a whitworth form of 55o .
This is super annoying. I decided to replace the hard-to-reach discharge valve on this compressor with a Husky extension, and I ran into the same crazy thread again. I remembered that I had had this problem before with another fitting on this compressor. Lo and behold, when I Googled, this discussion from 2014 popped up. I saved my own hide.
Now I have to make a fitting that's 0.505" in diameter with an 18 TPI male thread on one end and a 1/4" NPT thread on the other. Don't know if I'm even capable of doing that, but I guess I'm going to find out.
When you do it, you will like it. Really it should be done suspended above the bench or vise. It could be two boards or plates with nails or bolts sticking out. The heat is not evenly applied when on a bench, scorching the surface while the heat is disappated. You've cleaned the brass of oil film and heat it before it becomes oxidized apply flux. Before the flux is boiling out, apply solder. The heat is applied to where it draws the solder but suspended, the union is turned so liquid solder doesn't escape. When it is good, it is done. Anymore heat bakes it all out.
SteveHGraham wrote:I have a little Chinese (Eaton) compressor I used for cleaning and tire inflation. It has a really cheap vinyl-looking hose that goes from the pressure switch to the panel where the valves are. This hose is total crap, and to make it worse, it's held on by compression fittings which seem to guarantee that the end will split every few years.
I have some spare 3/8" hose, and I was going to replace the factory garbage with it. Problem: the valve/regulator manifold has regular threads that work with 1/4" NPT (ID) stuff. The valve on the pressure switch has a thread that looks the same, but it's actually about ten thousandths smaller in diameter (around 0.510" on the outside of the male fitting), and an American fitting won't go in.
Does anyone have any idea what size the thread is? It must be some crazy metric thing. I put the old hose back in today, but I want to order a fitting and put the other hose in it.
The rest of the world uses British pipe threads. 55 degree and I have run into them often on imported machines.
National PIPE thread, over here (and Europe) PIPE threads are classified by their bore. A 1/2" pipe thread goes on a 7/8" diam. I doubt if the thread is a proper metric one, its just some machine where the die box has not been adjusted properly. Depending on the pressure, just use sealer.
Frank
