need help with ph probe holder

julio martinez

FMAS Member/R/C Memeber
hi peeps, i recieved my ph probe holder from geo's today. i thought it was going to be a simple drill and tap procedure. i was half right, the drilling prt is not a problem. the problem is finding the tap that i need for the adapter. it needs to be a npt tap. does anyone here have one that i can borrow. i would take the lid of cal reactor to your place.
another thing that i was thinking of doing was using two rubber/nylon washers (one on either end of the ph holder) and attaching a nylon nut to the holder. but i dont know if it would work. what do you guys think?
any help would be appreciated.
Thanks, J
 
Just use some duct tape and superglue :D


What size tap you need? Just remembered I have a tap and die set down in miami. But i'm not sure if I have a npt tap.
 
thanks guys, but im not sure either. i was going to use a standard tap but i was told not to becasue the thread would not be the same. the thread for for npt is diff. i looked on line and found that a npt tap is $75.00 plus shipping. i just cant spend that $$ right now for a tool im going to use 1 time.
this is getting frustrating ughhhhhhhhhhhhhhhhhhhhhhhhhh!!!!
 
Screw what came with it then. Go buy a plastic screw from HD that IS a normal size that people do have drills and taps for.

Or if you are just trying to like extend two pieces of plexiglass as a hanger then drill two holes and zip tie it. Or get a longer piece of plexi.

There has to be an easy solution to what you are trying to do. Maybe you should explain it a bit more.


PH Probe Holder:

Strip of plexi - heat over stove - bend - drill hole - done.

PH-Probe.jpg


Although in this case, the bottom piece was glued rather than heated and bent.

Most probes come with a rubber sucker thing to stick to the glass. I just cut the cup off leaving the rubber band and that acts as the "stop" so the probe won't fall all the way through the hole.
 
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Julio, you should have send the lid to GEO to install the probe holder, i did it that way, you dont want leaks there.
 
AH duh. Now I see it's going in a lid of a CA Reactor.

I have the drill and tap that is for the 1/2" JG fittings which can be used as a Probe holder in a reactor so it may very well be the right size.
 
ok chucky here ya go. i have a calcium reactor that has two holes on the lid. 1 hole is for the water the other hole is or was for a pres gauge. in other words i have a cal reactor with a vacant hole on the lid. so i figured use that hole for the ph probe. so i went online and purchased a ph probe holder. holder comes in the mail, i take it home see that the hole on the lid is smaller than the probe holder. so i figure no sweat, make hole bigger to fit probe holder,tap hole,put in probe holder and insert ph probe. problem is standard tap thread is to thin for the thread on the probe holder. it wont screw in properly.
 
So use the 1/2" JG fitting from HD IF it is a different size than the holder you bought. Of course I'm a long way from you with the tap.
 
thanks guys.. i guess this type of stuff tends to happen as you get deeper in the hobby..
i'll try h.d. and if not i'll email george at GEO.
thanks again guys
 
I think you can get the tap cheaper than that if you needed to buy one. I think NPT actually has a slight cone shape to it like this ---> \ /

Check Northerns and Harbor Freight too.
 
all that the holder says is npt 1/2

I think that's the one; NPT thread should be 20 pitch.
We can drill a test hold on scrap, tap it and test before doing the real thing.
I will need a proper brill bit (I broke mine) but you can find those at any store for a couple bucks. I'll call you when I get home (the tap has the bit size on the side)
 
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