compressorhosetools
I have the compressor which can be seen below and I would like to connect one of the the two Alligator Compressor Nipples.
Question
Will the hose work with the first nipple?
Does there exist a special hose for the second nipple? Or does there exist a converter?
In addition to amperage, you should decide what voltage you want to be able to use, and if 220, which type of outlet you're likely to need.
A 220v welder will take about half the amperage of a similar 110v welder. 90-100 amps is fairly common, but you can find smaller (and larger) welders. An air compressor will probably take a lot less current, maybe 20-30 amps for 220v or 20-50 amps for 110v.
Look around at air compressors and welders you might eventually be interested in and you can get a good idea of the amperage you want to wire for.
You are correct that it is a good idea to use teflon tape on the threaded fittings, however no sealant is required or advised on the quick-connect part itself. These are designed to seal using internal o-rings.
There are multiple types of quick-connect air line fittings that at first glance appear similar, but are not necessarily compatible. It is very likely that you have connected two incompatible types, resulting in a leak. This is very common.
The two "main" types are often referred to as "automotive" and "industrial", though each can have sub-types that are typically letter designations, e.g. Industrial can be M, H or G. There's also a type called ARO, and one called Lincoln, but these are somewhat less common (at least in the US consumer market).
(image from Legacy Manufacturing)
The documentation for your air compressor may specify exactly which type of fitting you have. Otherwise head to the local big box store with your male coupling that leaks, and look for a similar-while-slightly-different male coupler to try.
Legacy manufacturing has published a very informative guide on the evolution of the various types of quick-connect fittings that lists the common types in use, with some images of each.
Milton Industries has also published a document that may help identify the type of plug you have, though their letter designations may not exactly match those of other manufacturers.
Best Answer
You are going to need an adapter to get the hose attached to the compressor, then another adapter to get the compressor nipple attached to the hose. The adapters look like this:
This nipple comes in a variety of sizes, so you have to match it for intended usage. This nipple will go into the coupler on the compressor and female threaded end would be attached to the top end (as looking at the picture) of the hose. You'll need another similar nipple attached to the end of the tool end which looks like this:
You'll notice the big difference here is that it has a male threaded end. This (obviously) will go into the female threaded end on the tool.
These adapters can be made out of brass, aluminum, or what have you. For best results, I've used Teflon tape around the threads to minimize air leakage.