Issue with compression fittings

Hey guys,

I got my fittings order in today and I have a slight issue. I ordered 3x 1/2 MPT x 1/4" tubing compression for my temp probes. The fittings I received are Swagelock, however they do not work as I expected. The 1/4" compression is tapered so that the probe will not fit all the way through. Is there another name for the fitting I'm looking for? I want to me able to stick the temp probes through the fitting and tighten for water tight.

Use o-rings around the probe to get them to seal up tight. Brewer's Hardware, and Brew Hardware both sell these ready to go. You can also find the o-rings on McMaster-Carr's site.

I have a few of the fittings from Brewer's Hardware and have one fitted in the assembly that goes onto my plate chiller, before feeding either to the kettle (recirculate) or into primary. I have the fitting set so that the thermometer probe will go all the way down past the ball valves, close to the output from the plate chiller. I'm also thinking about replacing the dial thermometer in my mash tun with one of these fittings, and use a k-type sensor through it (1/4" diameter sensor housing).

The Swagelok fitting needs to have the letters "BT" at the end of the part number for bore through needed to pass 1/4" probe all the way through. An example would be SS 400-1-8 BT for a 1/4" tube X straight fitting X 1/2" NPT male connection Bore through.
If you are careful and use a 1/4" - 9/64" cobalt bit you can drill out the fitting from the NPT side back to the compression side shoulder to make the probe fit. With a 1/4" bit a bit of effort is usually needed because the bit never seems to track perfectly on the first try and you have to wobble the bit a little to get the opening straight enough to work.

kladue said:

The Swagelok fitting needs to have the letters "BT" at the end of the part number for bore through needed to pass 1/4" probe all the way through. An example would be SS 400-1-8 BT for a 1/4" tube X straight fitting X 1/2" NPT male connection Bore through.
If you are careful and use a 1/4" - 9/64" cobalt bit you can drill out the fitting from the NPT side back to the compression side shoulder to make the probe fit. With a 1/4" bit a bit of effort is usually needed because the bit never seems to track perfectly on the first try and you have to wobble the bit a little to get the opening straight enough to work.

Click to expand...

I was going to post this exact thing. You have to specifically get the BT = "bored through" fittings from Swagelok if you need to have them go all the way through. I've drilled out a few of them with no issue, it's easiest with a drill press to make sure it goes in straight but it's actually pretty quick. The 1/4" are a little tough, 1/8" are wonderful to drill through, and 1/16" are a ***** because it's easy to break a tiny 1/16" drill bit.

Thanks guys, don't have a drill press but I know someone who does. I'm just going to drill out the fittings I have.

Another question if I drill out from the NPT side, would wort get "trapped" in the fitting since it would not be watertight on the NPT side? Granted it's not a lot of a room and probably only hold a tiny amount, just afraid of future infections.

Buy fittings from BrewersHardware they are ready for use with the correct o-rings

I hope this is for hot side and not fermenter temperature measurement, threads and tube fittings are a sanitation problem. Tube fittings should be dissassembled and cleaned after each use as trapped material will get infected, speaking from experince here with a CFC.

OneHoppyGuy said:

Buy fittings from BrewersHardware they are ready for use with the correct o-rings

Click to expand...

Hi

Well worth the money....

Bob

I also used swagelok fittings. All I had access to were non bored through. I went ahead and drilled them a bit small (I think it was 7/32") and then used a 22 caliber brass bore brush with different levels of polishing compounds on a drill to open them up to the perfect size as well as put a nice finish on the interior. I found that even using a press and drilling to exactly 1/4" with a bit of inaccuracy from the old drill press i used left a bit more slop for the 1/4" probe then I liked.