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what is the best type of disconnect for coolant hoses

rimcanyon

Diamond
Joined
Sep 28, 2002
Location
Salinas, CA USA
I need to plumb a new little giant coolant pump for my lathe. The pump takes ½" male fittings, the lathe has ⅜" female for the inlet from the sump and ⅜" male for the coolant pipe/nozzle. I'm thinking of using Parker 801 ½" hose for the inlet and ⅜" clear tubing for the outlet (tygon?). Barbed mpt fittings are plentiful, but I'm still looking for barbed fittings that are part of a threaded union of some kind. The original coolant hose fittings are 80 years old and don't seem to be a style that is readily available any more, but maybe I just don't have the right search terms. Also I am sure something with o-rings might be a better choice. Looking for some help. Here are a couple of pictures that show the original disconnects.

Intake hose:
IMG_0424.jpg

Outlet hose:
IMG_0425.jpg
 
There are a lot of hydraulic fittings available with swivel capability on a pipe thread. They're mostly plated steel, but should be ok for coolant. You don't need to use the crimp ferrules either. For low pressure a hose clamp is fine. I used these types of fittings for my TIG cooler.
 
There are a lot of hydraulic fittings available with swivel capability on a pipe thread. They're mostly plated steel, but should be ok for coolant. You don't need to use the crimp ferrules either. For low pressure a hose clamp is fine. I used these types of fittings for my TIG cooler.

That is what I am looking for: a swivel fitting with a barb.

This one is JIC: https://www.mscdirect.com/browse/tn...ZqfLvskv1QmL7HEkyW8f_9KLGYAxP9hsaApGTEALw_wcB

Is JIC a good choice for a coolant hose? I see lots of other standards, BSPP, o-ring boss, ...
 
Gotta be threaded union? If not, cam-lok may be an option. Inexpensive, available, available in a wide array of materials. They're not a swivel fitting, but they'll connect in any rotation.
 
That is what I am looking for: a swivel fitting with a barb.

This one is JIC: https://www.mscdirect.com/browse/tn...ZqfLvskv1QmL7HEkyW8f_9KLGYAxP9hsaApGTEALw_wcB

Is JIC a good choice for a coolant hose? I see lots of other standards, BSPP, o-ring boss, ...

For being able to switch back and forth between neat oils and Ho-Cut, have a look at "AN" series of Stainless, Brass, or Aluminium goods common on fuel systems.

"In other news...."

I don't like Tygon. But that's probably only because it has never held up as well for me as braid-in Neoprene & cousins.
 
Well, you can't afford 'best', but in lieu of that, look to the AN fitting world for hoses that are tough, versatile, compact, and will last beyond your lifetime. The new breed of braided hoses with the PVC (nylon?) liner is cost effective and rated for coolant and oil.

anplumbing.com
 
I'd rather go for stainless JIC instead of bling-bling rice tuner "AN" fittings.
JIC is same connector but "real AN"(SAE aerospace) is with tighter tolerances. Rice tuner "AN" fittings can be anything that looks similar. :angry:
 
I'd rather go for stainless JIC instead of bling-bling rice tuner "AN" fittings.
JIC is same connector but "real AN"(SAE aerospace) is with tighter tolerances. Rice tuner "AN" fittings can be anything that looks similar. :angry:

OK...if you paid attention, you'd see I recommended high quality, US made hoses. Not ricer hoses. If they're good enough for NASCAR and Formula 1 cars, they're good enough for you.
 
Gotta be threaded union? If not, cam-lok may be an option. Inexpensive, available, available in a wide array of materials. They're not a swivel fitting, but they'll connect in any rotation.

The smallest camlock fittings I could find were for ¾" hose. I think I will go with JIC. Not looking for bling.
 
I started replacing the pipe unions on my machines with camlock fittings. They are inexpensive and easy to use. No tools required to disconnect the pump and slide the whole coolant tray out. They make different gaskets for them too. Make sure you get the ones that are compatible with your coolant (oil resistant). They are available in poly(glass filled nylon), Aluminium and stainless if you really want to go fancy. 3/4” pipe is not too big either, unless you robbed your pump out of a fish bowl. With the larger hose, you will find your coolant flow will be much improved. You can always neck it down at the nozzle if you want to increase pressure or restrict flow
 
OK...if you paid attention, you'd see I recommended high quality, US made hoses. Not ricer hoses. If they're good enough for NASCAR and Formula 1 cars, they're good enough for you.

Sorry, Murican made blingbling tuner fittings ;)
No reason to use lighter weight alu fittings on a cast iron lump called lathe :D
 
Well, if aluminum bothers you for some reason, you can always specify steel fittings.

What you find, if you actually do it, is that the average machine tool has some very clunky and pain in the ass plumbing....and the flexibility, high flow, and wide variety of fittings used by AN plumbing is an 'upgrade' in every way.
 
The JIC fittings say "45° SAE/37° JIC" How can one fitting be both...


I don't get that either. They screw together and work, for low pressures in the few hundred PSI at least. The one size that doesn't intermingle is #6 - -6 45° is a larger thread than -6 37°, and that's probably the size you want for coolant.

I've used brass garden hose couplers with NPT thread fittings to make a no-tools disconnect, substituting an o ring for a gasket makes it compatible with coolant.
 
I don't get that either. They screw together and work, for low pressures in the few hundred PSI at least. The one size that doesn't intermingle is #6 - -6 45° is a larger thread than -6 37°, and that's probably the size you want for coolant.

I've used brass garden hose couplers with NPT thread fittings to make a no-tools disconnect, substituting an o ring for a gasket makes it compatible with coolant.
Maybe line contact for 45, and the whole face contact for 37 ?
 
I don't get that either. They screw together and work, for low pressures in the few hundred PSI at least. The one size that doesn't intermingle is #6 - -6 45° is a larger thread than -6 37°, and that's probably the size you want for coolant.

Maybe that is what is making this harder than it has any right to be ... I'm using ⅝" O.D. SS braided hose (already have it from an automotive project), ½" I.D., so I need (1) ⅜ mnpt x male 37 deg JIC at the sump, (1) ⅜ fnpt x male 37 deg JIC at the outlet stand pipe, and (2) ½ mnpt x male 37 deg. JIC at the pump (both directions). And I need (4) ½" barbed to 37 deg JIC swivel fittings for the hoses. I can't seem to find the ⅜" pipe fittings, and I keep hitting problems of knowing whether the swivel threads are the same as the threads on the male 37 deg. fittings. The info given in the listings on Grainger and MSC is really inconsistent in details like that, it assumes you know what you are doing and have been down this path a hundred times before ...

I'm trying to order from home, due to coronavirus stay-at-home orders, but a trip to the Parker store in town may be the best option.
 
McMaster has specs in depth on what they have in fittings, that is helpful, but I can't always find what I need in their listings. My Parker store always can fix me up, some few things need to be ordered like BSP threads.
1/2" swivels should be the same as 1/2 tube fittings, 3/4-16 threads whether 37 or 45 degree.
3/8 tube fittings are 9/16-18 for 37 degree and 5/8-18 for 45 degree. Any of these to any pipe size should be a readily available flared fitting.
Zoro/Grainger got me an odd fitting recently that McMaster didn't have and was too minimal to order from a local store, it was an oddball BSPP 3/8-19 90° to -4 7/16-20 JIC adapter with Oring swivel nut seal on the BSPP. I looked it up in Granger then ordered the number from Zoro. Took 10 days - go figure :)
What you are looking for I could pick out of the racks at my local Ace farm/hardware store plumbing department as long as i didn't need 3/8 37° flare fittings, for those I have to go to a hydraulic store or truck store.
 








 
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