Looking for an odd adapter, can you help? 3/8" UNF male union

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TT_Vert

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My IP gauge has a threaded adapter to convert it to the LP inflator hose QC however I want to screw it directly into the first stage. The gotcha here is that the IP fitting is a female 3/8 O-ring UNF and the 1st stage is also 3/8" O-ring UNF. So I need an adapter (union) that is male 3/8" O-ring UNF on both sides. I looked online at a few larger fastener stores and also home depot w/ no luck. I would screw the adapter into the 3/8" LP port on the first stage and then screw the IP gauge onto that adapter. I'd even consider male 3/8" UNF to something like 1/4 NPT then an adapter from NPT back to male 3/8" UNF. I did find this but it doesn't state its thread type or pitch.. https://www.fastenal.com/web/produc...ipcode=&filterByStore=&filterByVendingMachine=

Thanks for any help you may have!

Dave
 
None of those will work for me. This is being done just to test the IP of m first stage after rebuild. I want to connect my IP directly to my 1st stage LP port, not through a hose as the current adapter w/ the IP gauge allows me to connect to the inflator LP QC. To do so I need to unscrew the existing 3/8" UNF male fitting from the IP gauge and screw in an adapter that will make the other end of the IP connection a male 3/8" UNF to screw directly into my first stage. SO I need male/male 3/8" UNF on both sides of the adapter. If I could find out if "straight threads" are the same as UNF I have found an adapter that will work (I linked above.)


**EDIT** Sorry, I misread and thought that you didn't know what I was looking for.
Dave
 
Thanks, scubatools has mostly tools it seems. Didn't see it at northeastscubasupply but I do have an email into them. Perhaps someone can answer if UNF is the same as "straight threads"

Dave
 
My understanding is that "straight threads" simply means not tapered. They could be UNF, UNC or a host of others. (but not NPT, for example)
 
Thanks, I've got an email into Fastenal to see what type of threads their fitting is. Basically what I need is below but in 3/8" o-ring UNF.


a.jpg
 
Is there an adapter that converts male NPT threads on the gauge the Q.D. fitting? If so, then you could probably remove that adapter along with the Q.D. fitting and replace it with a female NPT to 3/8-24 male fitting such as this.

http://www.northeastscubasupply.com/1-4-npt-female-to-3-8-o-ring-1/

CAUTION: I should not have to ask this, but I will anyway. Do you have a means of relieving pressure in case of IP runaway? (i.e. a second stage attached or a pressure relief valve.)
 
There is and I though of this but by going gauge right to the 1st stage I lose my over pressure valve and also the relief to disconnect. This is the gauge I have and you can see that either I unscrew the QC adapter or the entire pressure relief body.. https://www.divegearexpress.com/regulators/regacc.shtml#2918

And for adapter I'd need an NPT FEMALE from the gauge to 3/8 UNF
004-893__75360.1408189621.1280.1280.jpg
This is another option I suppose if this is a 3/8" UNF o-ring. This would screw right into the first stage. Orrrrr, I just use the 22" LP inflator hose and not deal w/ any of these adapters. I wonder how much of a variance I'd have doing it this way vs. directly at the first stage.
040-163__70816.1408191209.1280.1280.jpg

Dave
 
https://www.shearwater.com/products/perdix-ai/

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