HERMS help - compression fitting doesn't fit!

[aangel]

Hey all. I bought some of the "true bulkhead" style weldless bulkheads with compression fittings. They're the 1/2" NPT to 1/2" compression type.

I also bought a 50' roll of 1/2" soft copper tubing.

Sadly, these two items do NOT fit together. The tubing's too big for the fitting. I checked the standards for this refrigerator tubing and it's supposedly exactly 0.50" outer diameter. And yet the two stainless steel bits that make up part of the compression fitting do not fit.

Help? Making matters somewhat worse I ordered from aliexpress so local return isn't an option.

 

[jcav]

Since you can't return the tubing you could try not using the two small ferrules that go inside the compression fitting. Instead put on two or three silicon keg post O-rings on the copper tubing and then put the compression fitting on. If it fits you can tighten down the compression fitting enough that the O-rings will make a seal and hopefully it won't leak. It will not be a permanent connection and can be removed in this fashion but it just may work for you. The "Electric Brewery" site does this on their counter flow chiller build. They use the O-rings on copper pipe and then attach a compression fitting. The pipe does fit in the first place though......

Here is a link to what I am talking about:

http://www.theelectricbrewery.com/wort-chiller?page=3

Brewers Hardware also does this with their compression fittings.

https://www.brewershardware.com/1-2-Compression-X-1-2-MNPT-Fitting.html


John

 

[Bobby_M]

Sometimes it pays to support vendors that take care of customer problems. Not that we've trademarked the name "true bulkhead" but I want to make sure people don't think the product I sell is the same as anything you find directly from Chinese vendors. My fittings are custom manufactured to my CAD drawings.

Put some calipers on the tubing and see what the measurement actually is. Do the same for the ID of the compression fitting. Which one is off? Are you sure the ends of the tubing aren't out of round? If the tubing is not marked "refrigeration", it's probably 1/2" nominal ID and will be 5/8" OD.

 

[aangel]

Hey Bobby, I would've loved to have bought the fittings from you but it's just as hard - I've had a lot of stuff from the USA get stuck at the border here in Canada. Somehow the Chinese vendors seem to be immune to this. Doing returns can be just as difficult to either country.

The tubing IS marked refrigeration; ASTM B-280 and that spec shows OD of 0.50" I'll be buying a tube cutter today to see if a pristine cut of it is to spec.

Hey JCAV: thanks for the info, I'll try that!

 

[aangel]

Followup: using a tube cutter, carefully, worked and the fittings went on. All except for one the one we tried to tighten on yesterday, and in doing so warped/compressed the inner two pieces enough that you can't slip them onto the copper tube now.

Now I just have to find a place to buy swagelok ferrules in Canada

 

[sasky7777]

On a side note, I have bought from Bobby a few times, and have never had border issues. 90% of my brewery came from the US and I never had issues.

 

[Bobby_M]

True, about 5% of our sales are to Canada and I don't remember the last time we had a delivery issue. USPS works well.

 

[jcav]

Just so you know I did buy my "True Bulkhead" compression fittings from Bobby, to install my herms coil in my HLT. The fittings Bobby sells are top notch! I could not get over the quality, they are extremely well designed and made with a solid piece of hex bar stock, and are very heavy stainless steel. The way the O-rings fit in the machined grove is genius and once you tighten it down it will not leak. Here is a link https://www.brewhardware.com/product_p/truebulkhead12comp.htm
Also if there is a problem with anything you order from him, he will always stand by his products and make it right. Real quality items that last..........

John