temp gauge

[CJBrew]

The male stud coupling was MC104/081
(it can be 1/4" bsp if you preferfor a greater depth of thread, as long as you get the correct back nut).

and they also supplied the back nut seperately, no idea what part number that was, all you need to ask for a 1/8" bsp back nut or a back nut suitable for the stud coupling.

The thing I can't figure out with these fittings is what the big nut on the other side is (the side that's not 1/8" diameter). Is this a 15mm compression female fitting? I am looking to buy one of the thermometers that have a 1/2"BSP threaded part on the stem, and am hoping to be able to just screw this into the coupler.

I think what I am looking for is something like

Code: Select all

[code]Cross Section:

Inside                     Outside
 
              |P|  /---- Pot skin
              |P| /
     back     |P| 
      nut ||  |P|
         /||  |P|  ------------------
        |nn|  |P|  |AA|\/\/\/\/\/\/\/
  /\/\/\/\/|       |AA|      \
  |AAAAAAAA|-------|AA|       \ thermometer screws in here
  =====================
  
                    ---- thermometer stem passes through
                    
  =====================
  |AAAAAAAA|-------|AA|
  \/\/\/\/\|       |AA|
        |nn|  |P|  |AA|/\/\/\/\/\/\/\
         \||  |P|  ------------------
          ||  |P|
              |P|
              |P|              

[/code]

[mooj]

The compression side is 4mm, the other is a 1/8"BSPP thread and not the same as 1/8" diameter. The compression fitting clamps and seals the temp probe.

With regards to your idea, I assume you are talking about a thermometer with a taper threaded stem? If so the fitting you describe/show is a bspt socket to bspp male adapter - I'm not sure how common this fitting is but check it will have a flange to seal against the pot. Other than that you could try a BSPTM -BSPF bush, again I don't know how common this fitting is or whether it will have a flange to seal against.

I can't help thinking you're complicating things by wanting to do it this way as I can't see the benefit over Chris' suggestion.

[Johnnyboy]

Would it be possible to fit one of those to a cool box type mash tun, as there are two walls and I presume you would get leakage into the insulation area????

John.

[CJBrew]

I can't help thinking you're complicating things by wanting to do it this way as I can't see the benefit over Chris' suggestion.

possibly. But why else do the thermometers have the BSP tapered threads? Surely it's so you can screw them into a fitting on a pot...

[mooj]

I can't help thinking you're complicating things by wanting to do it this way as I can't see the benefit over Chris' suggestion.

possibly. But why else do the thermometers have the BSP tapered threads? Surely it's so you can screw them into a fitting on a pot...

They are common in industry for sure. I've just not seen the fittings you would need readily available or if even they would suit the purpose. I'm still not sure what benefit you think it will have.

[CJBrew]

I've just not seen the fittings you would need readily available or if even they would suit the purpose. I'm still not sure what benefit you think it will have.

Someone suggested using a combination of bushes and nipples -- I don't know.

Can I confirm, you're suggesting ignoring the threaded connection on the thermometer pocket (stem) and sealing the stem in with a compression fitting + olive?

[Scooby]

I've just not seen the fittings you would need readily available or if even they would suit the purpose. I'm still not sure what benefit you think it will have.

Someone suggested using a combination of bushes and nipples -- I don't know.

Can I confirm, you're suggesting ignoring the threaded connection on the thermometer pocket (stem) and sealing the stem in with a compression fitting + olive?

You need a 1/2"bsp full socket, 1/2" nipple, washer, back nut and 'o'ring/washer. It's sometimes sold complete as a weldless fitting and is very commonly used to fit thermometers, ball valves and sight tubes. The socket, nipple and 1/2" stainless lock nut can be had from BES and the M22 form B washer from Stig's stainless fasteners

[CJBrew]

I think the right "bulkhead fitting" would probably do the job

http://www.airlines-pneumatics.co.uk/we ... de=S010128

[mooj]

Can I confirm, you're suggesting ignoring the threaded connection on the thermometer pocket (stem) and sealing the stem in with a compression fitting + olive?

Chris' method is for a plain temperature probe with no thread but yes the olive and nut provide the seal.

You need a 1/2"bsp full socket, 1/2" nipple, washer, back nut and 'o'ring/washer. It's sometimes sold complete as a weldless fitting and is very commonly used to fit thermometers, ball valves and sight tubes. The socket, nipple and 1/2" stainless lock nut can be had from BES and the M22 form B washer from Stig's stainless fasteners

I must admit I'm surprised you get a good seal between the taper thread and the parallel socket but it must work so who am I to argue. Scooby, do you need any additional sealant for this between the washer and socket and / or the thread?

I think the right "bulkhead fitting" would probably do the job

http://www.airlines-pneumatics.co.uk/we ... de=S010128

If the above works for Scooby, then provided you can get a o-ring / gasket to suit I don't see why this shouldn't work also.

[Scooby]

I must admit I'm surprised you get a good seal between the taper thread and the parallel socket but it must work so who am I to argue. Scooby, do you need any additional sealant for this between the washer and socket and / or the thread?

It's normal practice to apply teflon tape to a taper thread, no leaks on the thermometer and I also use the same system on my ball valve but with the socket on the inside which means I have a 1/2" male thread to attach the valve and 1/2" female thread to attach hop filters or add a nipple for a male.

The socket on the outside is ideal for mounting a thermometer such as that to a cool box tun as it bridges the gap between the inner and outer skin.

There must be hundreds of them in use, although no HB shop sells them here they are freely available in the States and Ross at Craftbrewer sells them.

[beer today]

great thread guys, anyone be a little more idiot tolerant with regard to fitting a temp probe thru a coolbox, nipples/pockets/ 1/2" whatnots ,all a bit too vague for a numpty like me, any pics please ?
thanks

[Scooby]

Just carefully drill a clearance hole in the outer skin and remove the insulation down to the inner skin.

Drill a hole and fit a stud coupling to the inner skin as per Chris's example. The probes are normally 100mm plus in length so they should clear the outer skin but still have 50mm plus inside the tun which is enough to read the temp accurately.

[beer today]

ah I see, so the coupling will obviously be flush to the inner skin but not sit proud of the outer skin, it will just sit in the area where the insulation has been removed.
I was thinking the coupling would be external to the outer.