View Full Version : Where to buy that adapter female 16x1.5mm / male 1/2 NPT

Boyan Silyavski
23-06-2015, 12:12 PM
I would like to fit to my Stalhwerk plasma a proper Thermal Dynamics torch /SL100/.

Now being a China plasma it has 16mmx1.5 male protruding connector and at the other side i have 1/2 NPT female.

So I need something like that:

female 16x1.5mm / male 1/2 NPT

It seems difficult to find and where i found it they want 2 euro for the connector and 30 euro for handling :listening_headphone

here is another one i found but am still waiting to seeif there is something better and cheaper. Or at least from Europe

Siemens 3SX1997 International Limit Switch Adaptor For 3SE, Metal, M16 x 1.5 to 1/2" NPT (http://www.amazon.com/gp/product/B009B1Q5P8/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B009B1Q5P8&linkCode=as2&tag=dogshockcol06-20&linkId=WVUO5FALVWYDHR5K)

Any idea on that? It seems its a kind of some electrical standard adapter. I searched RS, couldn't find it.


23-06-2015, 11:36 PM
Are you sure it's 1/2" NPT you need?
Only reason I'm asking, is that image is totally wrong if it is. 1/2" NPT has an OD of 21.6mm, whereas the M16 has an ID of 14.5, so the male threaded section should be larger than the female section.
Have you tried hydraulic connectors?
I'd have a look, but all my hydraulic fitting catalogues are in the workshop, and I won't get anywhere near them until late tomorrow. How much room have you got, as it may be easier to go via BSP fittings.

24-06-2015, 07:43 AM
Think the NPT is the female thread and the male the Metric end.

24-06-2015, 10:11 AM
Think the NPT is the female thread and the male the Metric end.
You're right. I'll blame lack of sleep!
Nothing in any of the hydraulics catalogues I have, but the above link will be for conduit.
M16 is quite popular in industry for electrical/cable glands, and the yanks love their imperial steel conduit. Europe just goes for plastic conduit or armoured cables, so it's not something likely to be found as easily over here.

Boyan Silyavski
24-06-2015, 04:34 PM
Hi guys,

i believe i mislead you, also due to a lack of sleep :cat:

The connector is smaller than the m16x1.5 chinese connector.

I was browsing some forums for an answer and somewhere i read that 1/2 NPT is the standard for the american made plasma machines so i assumed without thinking it further that this is the case here. Cause the Thermal Dynamics universal torch sells or in ATC Connection or in something called O2B Connection . I bought mine with the ATC connector which is proprietary, looking something like a Mig Euro-plug and additionally bought the short adapter which adapts it to something which i assumed was the 1/2 NPT

Now here are some photos, the thread seems similar like the 1.5mm thread but this i can not confirm as i dont have all thread gauges and the ones i have dont enter properly so its difficult for me to judge.

Maybe hopefully its some popular thread. Now my bad was that i went to industrial shop and there was a fitting that almost fit at the side of the hose, but i did not ask him which size was, as i was still under the 1/2 NPT impression. :beaten:

Right photo is the new one, left is the bigger Chinese 16x1.5mm

PS.Just checked again with the thread gauges i have, the thread seems more near 1.25mm size or 20G 1/4 BSW



24-06-2015, 11:30 PM
Going by the hydraulic fitting chart I have, inside diameter of 12.5mm would likely be M14x1.5, or 12.9mm would be 9/16"-18 UNF. The chart only covers BSP, UN, NP and Metric threads though.
However going by the charts here - http://www.motalia.com/Html/Charts/thread_charts.html, the only thing near given the ID and pitch, would be 9/16"-18UNF, which given the American origin, I'd say is the most likely.

Boyan Silyavski
24-06-2015, 11:47 PM
Thanks for that.

Arent they bastards. I read this evening that american companies, like Miller and so tend to use metric or rare threads. Why? To f___ck their customers and discourage them from "this fits to that"

9/16"-18 UNF, i hear for that one for first time in my life :-). I also concluded that that M14 is a worthy candidate. As there are some Chinese adapters on the market that fit China plasma torches to 14x1.5 machines. Unfortunately the opposite to what i am going to do.

Will go tomorrow again to the local industrial supply to see what was the one that fit. A bit shameful having a lathe and don't know how to make the adapter myself :distracted:, but don't have the time to dig into that

Boyan Silyavski
25-06-2015, 12:05 AM
Ok. I found it. It does not show from ebay search from Spain :mad:. Fortunately found it from the .com site :cat:. Item number 251342793854, 4.50$ . Just ordered it.

I hope that's the one. If not i will brutalize it and make it fit :anonymous:


25-06-2015, 08:43 AM
A lot of Companies use special(odd) size threads so you are tied into buying there spares.
The fitting shown should be fine if its got a cone in the M14 end and if not that's easy enough to do on your lathe.