How do I reliably attach 1/4" ID hose to smooth 1/4" OD Stainless Tubing?

I'm working on a project I hope to share soon, but it involves attaching 1/4" ID vinyl hose to 1/4" OD stainless steel tubing. It will be subjected to room temperature carbonation pressures (possibly 60 PSI?) and I don't trust clamping the hose onto the smooth bore tubing.

My thoughts were to create some 'barbs' on the SS tube. I can get 5/16" OD SS that is just over 1/4" ID - I could silver solder (or lead free solder, I guess - I'll check the 'sticky' again later) a small ring of that 5/16" over the 1/4" to form a 'barb', and then clamp behind that 'barb'. Or maybe a 1/4" copper ferrule would do (coated with solder)? Or maybe rings of X gauge copper wire wrapped and soldered to from a barb?

This connection would not need to be removed, so I'm also thinking of adding a bit of aquarium silicone to the connection. Hose clamp behind the 'barb' after curing.

Those are my ideas, but maybe this has been tackled before and I'm missing the obvious. Any thoughts? Will my ideas work? Are there better/simpler approaches?

TIA - kenc

You could flare the end of the tube a bit, then heat the vinyl tube to go over it. Put your hose clamp in front of that and it should hold pretty good.

I'd say you have two realistic choices- either find somewhere nearby that has a tube beading tool, or use some compression unions on the end. Anything less than that is not going to reliably hold 60psi, most likely.

I bet a flare tool would put a nice flare into your SS pipe depending on the wall thickness and then a worm gear clamp would hold it down just fine. I really don't think 60PSI is that much and really a good socket wrench on a worm gear clamp would work just fine.

I also suspect the smoothness of the SS will help the tube to create a seal and would be worried about adding/soldering a bump onto it to keep it on. I'm thinking to how many automotive applications I've seen that run very high pressure and only use a tube and worm gear clamp...

Maybe some pics. Let us know what works for you.

McMaster doesn't seem to like links, but go to

www.mcmaster.com

tube fittings > push to connect > coupling

The 1/4" push to connect union should work for you.

I would get a 1/4" compression to 1/4" NPT fitting amd a 1/4" FNPT to 1/4" Hose Barb fitting.

Here are my results testing various clamping systems:
https://www.homebrewtalk.com/f11/wh...silicone-tubing-hose-barb-190317/#post2232957

Thanks, some good suggestions/info here. Though I may need to do this on quite a few connections, so I'm trying to do it on the cheap, if I can also do it reliably.

Let me re-phrase the question:

Rather than 1/4" ID hose, if I use some of that thick-walled beverage line (my LHBS carries the BevLex 200 series), 3/16" ID x 7/16" OD, heat it in near-boiling water to soften it and force it over the 1/4" SS - will that hold reliably with a clamp? I've tested one sample and it seems good.

I also didn't see any references to these types of hose clamps in the above link:

http://www.usplastic.com/catalog/item.aspx?itemid=23427



Anyone have experience with them? Look cheap and are re-usable, no special tools and won't corrode. Looks like they have a pretty limited range - you need to get the exact size for your hose OD.

-kenc

The one downside of the plastic clamps that you have pictured is that it's hard to get them really tightened down. I've had systems that leaked with those guys, but worked great when I replaced them with a decent worm clamp.