How to attach Auber RTD sensor in my Blichmann pots?

[kal]

Yup, metal on metal is not good, but take a look at the picture I posted above from the Blichmann manual on how it works. It's not metal on metal:

Maybe it's just me then but I really like the way Blichmann does it as it makes sure you don't overtighter the nut. You could throw an extra washer on the inside but I don't think it's probably needed.

BTW, I emailed John Blichmann last night and I already had an email this morning indicating that he'd update the next print run of their Boilermaker and Brewmometer manuals to include more labels like my Figure 2 above (to make it clearer for people what's what). I've always been impressed with their service. 5 thumbs up!

Kal

 

[kal]

Justin,

What's that little plug called that the probe screws into?

Kal

 

[Boerderij_Kabouter]

Thats a hex bushing or simply a bushing. Here is a page:

Bushings-Hex

That site has the cheapest stainless I have been able to find.

 

[Evan!]

I'm confused. You shot down every suggestion and still claimed confusion.

I'm confused about your confusion over his confusion.

 

[kal]

Thats a hex bushing or simply a bushing. Here is a page:

Bushings-Hex

Cool. Thanks.

Oh crap. I ordered three of these metric M16x1.5 threaded sensors from Auberins (before I thought about putting one or two in the plumbing instead of the pots):

How am I going attach one of these into a Hex Bushing which screws into the 1/2" stainless tee? I need some sort of M16x1.5 to 1/2" NPT hex bushing, no? (Doubt anyone makes something like that).

Should I have ordered sensors with 1/4" NPT thread instead for the ones going in the plumbing?:

These would then fit into 1/2" x 1/4" Threaded NPT Hexagon Bushing on this page right?: 1/2" x 1/4" Threaded NPT Hexagon Bushing SS I=.94 J=.83

(This would then go into the 1/2" stainless tee that I've also ordered).

Crap.

That site has the cheapest stainless I have been able to find.

I just bought a couple of hundred worth of valves and fittings from BargainFittings.com (got it off your spreadsheet). Good prices and cheap shipping (I'm in Canada).

Prices are great too. For example: A stainless steel 1/2" full port ball valve with Stainless nipple, washer, coupler, locknut, and 2 Silicon o-rings: $26 USD. NorthernBrewer wants $37 and the locknut is brass not SS either (not that that really makes a difference since it doesn't contact the wort - just doesn't look as purdy).

Kal

 

[Boerderij_Kabouter]

oooooo if you can change your order I would. It will be difficult to find that adapter.

If you are stuck with the metric, your best solution may be to buy a 1/2 to 1/8" hex bushing then redrill and tap it for the M16. That may be difficult in the stainless though....

sorry

 

[kal]

Order's already on the way. Looks like I'll just have to order some more RTD sensors (at least 1 or 2). Oh well. I knew there would be some redesigns/mistakes.

I can't (won't) get into trying to drill/tap my own bushing.

Thanks Justin.

Kal

 

[The Pol]

Why would you ever buy metric anything? Isnt it just as easy, or easier to build anything with the english equivilent?

 

[Boerderij_Kabouter]

Yuri suggested the metric, maybe because it had the smallest footprint...?

 

[kal]

I don't know. Maybe because the NPT is not a straight thread? Will the 1/4" NPT probe even fit in the bushing?

In other words, with a bit of plumbers tape wrapped around the thread of this 2" probe:

Will it fit into this 1/2" x 1/4" Threaded NPT Hexagon Bushing bushing?:

The 1/4" NPT probe order page says:

"It can be easily installed either on the tank or on the pipeline (with a T joint)."

Kal

 

[conpewter]

Yup, metal on metal is not good, but take a look at the picture I posted above from the Blichmann manual on how it works. It's not metal on metal:

Maybe it's just me then but I really like the way Blichmann does it as it makes sure you don't overtighter the nut. You could throw an extra washer on the inside but I don't think it's probably needed.

BTW, I emailed John Blichmann last night and I already had an email this morning indicating that he'd update the next print run of their Boilermaker and Brewmometer manuals to include more labels like my Figure 2 above (to make it clearer for people what's what). I've always been impressed with their service. 5 thumbs up!

Kal

A couple thoughts.

I like the above idea not only because it keeps you from squishing the O-ring but also because you can crank down on it and make it really sturdy (My ball valve on the keg is a bit wobbly, but it seals...)

Also Yuri suggested to go with the metric most likely because you don't want NPT, you want a straight threaded (not pipe thread). That way you can screw the nut all the way on to get it tight enough to seal.

Edit: I'm not sure if that bushing will work, it will need to screw down far enough to pull the O-ring taught.

Also I wouldn't use any pipe tape, you arn't making the seal on the pipe threads, it is all up to the O-ring.

 

[kal]

I like the above idea not only because it keeps you from squishing the O-ring but also because you can crank down on it and make it really sturdy (My ball valve on the keg is a bit wobbly, but it seals...)

I never thought of that as being a benefit but you're absolutely right. I'll have to see if I can find larger washers for my setup to do this for all my valves and other weldless fittings.

Also Yuri suggested to go with the metric most likely because you don't want NPT, you want a straight threaded (not pipe thread). That way you can screw the nut all the way on to get it tight enough to seal.

Good point.

So I've learnt a few things after looking up NPT on Wikipedia.

NPT (National pipe tread) is tapered by definition. This would most definitely be the reason why you want straight thread if you going through a bulkhead and using a nut to attach. But to go into a NPT bushing you'd use an NPT probe I would think.

Slowly getting clearer and clearer. I'm an electrical engineer, not mechanical.

Edit: I'm not sure if that bushing will work, it will need to screw down far enough to pull the O-ring taught.

Also I wouldn't use any pipe tape, you arn't making the seal on the pipe threads, it is all up to the O-ring.

O-ring? I was referring to Justin's suggestion to do the following:

No o-ring required right? Just screw the 1/4" NPT temp probe into the 1/4" NPT bushing. No?

Kal

 

[Boerderij_Kabouter]

As far as the bushing goes, just screw it in. I would use pipe tape and not an o-ring.

Thios straight thread stuff is interesting.... I will have to look into it more.

 

[conpewter]

No o-ring required right? Just screw the 1/4" NPT temp probe into the 1/4" NPT bushing. No?

Kal

Right I was still thinking of having it in the wall of the keg/bulkhead fitting (how I think mine will be), you are correct on using the NPT bushing with plenty of pipe tape.

 

[BrewBeemer]

(the washer doesn't compress the o-ring). It would seem they do it this way to ensure that the o-ring doesn't get squashed by someone over-tightening the nut on the inside. I think they're trying to patent the idea too.

Kal

I really doubt this is something new and requires a patent on with those rubber coated washers, this was applied to the fuel petcocks on british motorcycles especially Nortons back in the 60's, and way before this is nothing new here.
Questions I have is there a 1/2" threaded RTD or probe available? just order a 1/2" rubber coated washer and be done with it? I still would add a thin nylon washer preventing scoring up the inside surface of that new pot if it were mine. If the 1/2" threaded probe is not available and that probe you have is 1/4" or a metric thread this is what I would do. Take some stainless stock and thread the ID to match the probes thread, thread the OD to 1/2-13 unless you want fine thread. Cut this threaded sleeve the same length as the probe thread minus the thickness of the stainless washer you might have to add, the washer ID should match the original probes thread diameter then screw on the sleeve. I bet across the flats of the 1/4" probe this space is about as wide as the 1/2" hole already or less. Use silicone sealer on the threads inside this sleeve as liquid will leak up the sleeves threads plus I would use a fiber washer remember those red washers used on carbs and fuel line connections? Available at any "GOOD AUTOMOTIVE PARTS STORE". Add some silicone on the fiber washer plus the sleeve OD, after inserting into the pot before adding a thin nylon washer and nut. You can crank down on the nut rather tight. Wipe off excess silicone, let air it dry overnight and be done with. Just ideas unless as I said before there is a 1/2" probe available? Adam should be able to chime in on what's available on different available probes unless you look on line yourself.....Carl.........

 

[kal]

I really doubt this is something new and requires a patent on with those rubber coated washers, this was applied to the fuel petcocks on british motorcycles especially Nortons back in the 60's, and way before this is nothing new here.

Just quoting Blichmann. Don't shoot the messenger.

Questions I have is there a 1/2" threaded RTD or probe available?

Not that I've seen. Otherwise that would be an easy solution.

If the 1/2" threaded probe is not available and that probe you have is 1/4" or a metric thread this is what I would do. Take some stainless stock and thread the ID to match the probes thread, thread the OD to 1/2-13 unless you want fine thread. Cut this threaded sleeve the same length as the probe thread minus the thickness of the stainless washer you might have to add, the washer ID should match the original probes thread diameter then screw on the sleeve. I bet across the flats of the 1/4" probe this space is about as wide as the 1/2" hole already or less. Use silicone sealer on the threads inside this sleeve as liquid will leak up the sleeves threads plus I would use a fiber washer remember those red washers used on carbs and fuel line connections? Available at any "GOOD AUTOMOTIVE PARTS STORE". Add some silicone on the fiber washer plus the sleeve OD, after inserting into the pot before adding a thin nylon washer and nut. You can crank down on the nut rather tight. Wipe off excess silicone, let air it dry overnight and be done with. Just ideas unless as I said before there is a 1/2" probe available? Adam should be able to chime in on what's available on different available probes unless you look on line yourself.....Carl.........

So instead of spending $30 on a new probe and $2 on a bushing, spend $10-20+ on some stainless stock and other supplies and get it machined exactly right? Sorry, but this is an insane amount of work and running around to save about $5-10 assuming I can get the machining done for free. I don't have the means to machine stainless nor do I want to learn or figure out how to do it to save $5. Sorry Carl!

Kal

 

[kal]

A funny thing happened to me on the way to the brewery ...

Auberins sent me three 1/4" NPT temp probes instead of the three M16x1.5 I had requested so this actually works out pretty well. I can use two with standard 1/4" to 1/2" bushings in the plumbing. Easy as it's all standard.

For the Brew Kettle I'd like to use the existing 1/2" diameter hole that's there for the Blichmann analog Brewmometer. I'd prefer to not make the hole larger in case I want to undo what I've done.

So do I put in a M16x1.5 or 1/4" NPT RTD temp probe from Auberins? The 1/4" NPT probes are just a little too big as is. I'm assuming M16 is slightly larger still (16mm is 0.6299").

So without making the hole bigger, can I keep my 1/4" NPT probe and put in some sort of bulkhead that'll fit in a 1/2" diameter hole? Can't seem to find anything like that. I don't want to machine anything. Click and buy.

Kal

 

[Boerderij_Kabouter]

Question: The hole for the Blichmann thermometer is 1/2" diameter? That is tiny!

In your OP you list the metric thread as an M16. Which is it?

McMaster # 48805K252 is an adapter from 1/4" FPT to 1/8" MPT but I doubt the probe will fit through a 1/8" hole.....

:EDIT:
Here is the adapter from McMaster

 

[BrewBeemer]

I'm confused about your confusion over his confusion.

Now that about covers it all, that's worth a +10 in points reply.
If ya can't laugh you'll cry KAL.

 

[BrewBeemer]

Just quoting Blichmann. Don't shoot the messenger.


Not that I've seen. Otherwise that would be an easy solution.


So instead of spending $30 on a new probe and $2 on a bushing, spend $10-20+ on some stainless stock and other supplies and get it machined exactly right? Sorry, but this is an insane amount of work and running around to save about $5-10 assuming I can get the machining done for free. I don't have the means to machine stainless nor do I want to learn or figure out how to do it to save $5. Sorry Carl!

Kal

My stock be it aluminum, brass, copper, steel, stainless is within 20' of the lathe no running around in my case or material costs. To get someone to machine for free that would have to be a family member as time and machinery like a lathe are not a cheap investment tool especially a American made lathe not one of those Harbor Freight quality units. As far as making the valve more stable with less flexing of the pot at the valve I would add a stainless fender washer on the inside of the pot then the nut this would also prevent any scoring from the nut turning against the pot plus stiffen up the valve when your pulling on the lever. I would slightly bow the washer to the radius of the pot before assembly.
Hell by the time you get squared away a stout will of been done fermenting there boss. I must see problems and take care of them in a different way thinking mechanically vs a on paper person, sorry Kal I tried with ideas on what I would do to solve your problem with a few ideas. This makes me believe setting up and operating a Bridgeport mill or lathe may be beyond the scope of your background training. I was raised differently I guess at a very young age, built my own C class (30 cu/in mono hull racing motors from stock Mark 30H Mercury motors with quickies as my dad would not show me more than once how to do things or set up the mill more than once back when I was 15. I set up and modified my own pistons and porting without his outboard racing experience help years ago. I was so damn pissed at him back then but respected what he did to me later in life that was thinking things out on my own. The best reward I got was championship that year on my own motor build. Dad called it hands on you'll learn faster that way failures included. Yup had failures exploded a motor that same year my fault and dad did not help prevent this future doomed motor failure I had to think on my own what went wrong.

Question Kal;
do they have the same disconnect style fittings you have pictured but in TC probes instead of RTD's? The BCS 460 controller needs 10K ohm resistance probes this means the RTD probe will not match the 460 controller a totally different resistance operating range.
I like that removable cable feature for the probes you have making it handy to remove or transport the keggkes.
Don't forget to check your local marine supply store for stainless parts. I'll purchase items 15 different times for other projects there before one is used for marine use. A good supply source in stainless hardware just expensive.

 

[kal]

Question: The hole for the Blichmann thermometer is 1/2" diameter? That is tiny!

Yup. That's what it is. The Brewmmeter shaft is 1/2-20 UNF thread (I asked).

In your OP you list the metric thread as an M16. Which is it?

Oops - sorry about that. Fixed. It's M16. That makes a lot more sense as M16 is a regular size.

McMaster # 48805K252 is an adapter from 1/4" FPT to 1/8" MPT but I doubt the probe will fit through a 1/8" hole.....

Is there any way to figure out how big that hole in the adapter actually is (whithout buying it of course)? I know that the inch sizes of NPT stuff is the pipe size but that pipe size isn't actually, well, the size of the pipe! (Ex: 1/8" NPT pipe has an OD of 0.405" not 0.125). I'm sure this makes logical sense somwhere.

The probe on both the 1/4" NPT and M16x1.5 probes is 6mm in diameter (just a smidgen under 1/4").

I'd probably want a metric thread adapter anyway so that the smaller thread inside the pot is not tapered anyway and McMaster doesn't make metric adapters, only NPT, BSPT, UNF.

do they have the same disconnect style fittings you have pictured but in TC probes instead of RTD's?

Yes, they have a TC probe too with a disconnect, along with the two RTD's listed in the original post. You can see what they sell on two pages:

RTD: http://auberins.com/index.php?main_page=index&cPath=15
Thermo: http://auberins.com/index.php?main_page=index&cPath=3

The BCS 460 controller needs 10K ohm resistance probes this means the RTD probe will not match the 460 controller a totally different resistance operating range.

The PIDs I'm using support dozens of sensor types. Doesn't seem to be an issue.

I like that removable cable feature for the probes you have making it handy to remove or transport the keggkes.

Me too - it's the main reason why I want to use them. The only issue is that the wires are very small and seems reasonably fragile so I'm going to add some braided sleeve around the thin wires and some sort of steel cable inside too with a bunch of shrink wrap to ensure that I don't end up breaking one of the wires over time.

Thanks!

Kal

 

[Joust]

I'll trade you my m16 probe for one of your 1/4" NPT probes. makes no diff to me.

A funny thing happened to me on the way to the brewery ...

Auberins sent me three 1/4" NPT temp probes instead of the three M16x1.5 I had requested so this actually works out pretty well. I can use two with standard 1/4" to 1/2" bushings in the plumbing. Easy as it's all standard.

For the Brew Kettle I'd like to use the existing 1/2" diameter hole that's there for the Blichmann analog Brewmometer. I'd prefer to not make the hole larger in case I want to undo what I've done.

So do I put in a M16x1.5 or 1/4" NPT RTD temp probe from Auberins? The 1/4" NPT probes are just a little too big as is. I'm assuming M16 is slightly larger still (16mm is 0.6299").

So without making the hole bigger, can I keep my 1/4" NPT probe and put in some sort of bulkhead that'll fit in a 1/2" diameter hole? Can't seem to find anything like that. I don't want to machine anything. Click and buy.

Kal

 

[kal]

I'll trade you my m16 probe for one of your 1/4" NPT probes. makes no diff to me.

Thanks Barry! Glad to know I have options. What I don't seem to have an option for is to put in the boil kettle using the existing 1/2" dia hole. I should just use a 100 ohm resistor on the pid and just use the existing Blichmann Brewmometer. All this work just so that I don't have a boil kettle temp reading fixed at 72F. Sheesh. Seems kinda silly.

Kal

 

[Joust]

i like to be "in the know"
it seems that M16 is 0.638 inch hole size required.

 

[Boerderij_Kabouter]

Kal,

I think you need to invest in a dremel. That would be by far the easiest fix for this. Or a step bit, one of the two.

 

[kal]

Kal,

I think you need to invest in a dremel. That would be by far the easiest fix for this. Or a step bit, one of the two.

I have both. A fix for what exactly? (Remember that I'd prefer to re-use the 1/2" dia whole in the Blichmann pot for a temp sensor in the BK).

Kal

 

[Boerderij_Kabouter]

I was just referring to expanding the hole slightly. I know it isn't exactly what you want, but it may look better that way than it would if you have to use a weird adapter... ??? Who knows. This is an interesting problem you have found though

 

[kal]

Yup. Not really much of a problem since most of the temp sensors will go in the plumbing. The BK temp sensor is a "just because" addition. It isn't even needed!

I think I'll just build up everything and see how much it bugs me to not have the BK temp displayed digitally.

Kal

 

[Boerderij_Kabouter]

ooohhhohoohohho... what about this!

Could you tap through the hole so that the RTD would thread directly into the pot?

 

[kal]

Slightly off topic, but for those that are curious: While the probes from Auberins come with really handy detachable heads (at the kettle), the 3-wire teflon coated conductor cables don't look like they'd stand up a lot of abuse over time:

I'm going to likely run them through some sort of narrow diameter hose wrapped in stainless braid to give it a nice finish and some protection.

Stainless braid:

The ends will then be shrink wrapped to avoid fraying.

Note: Stainless braid is expensive. McMaster has tinned copper braid for about 1/2 the cost ($1/foot for 1/4" dia) that I may use instead.

Kal