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Red Hot Blue glue vs Clear Glue and primer

Posted: Tue Nov 20, 2007 9:26 pm
by spudgunnerwryyyyy
All of my plumber friends swear by red hot blue glue because it has the glue and primer in one can. This I know is true but our method of separating primer and cement must be stronger. This is because we soften the pvc before. Any comments. I need to be able to tell plumbers that red hot blue glue isnt that great.

Posted: Tue Nov 20, 2007 9:30 pm
by Maniac
i dont soften my pvc are you saying the primer softns it or we heat it up srry just dont understand all of what your saying. but you cold pressure test the red hot and see if it will blow off. not saying to blow up the pvc but test it to about 250

Posted: Tue Nov 20, 2007 9:38 pm
by Fnord
The primer cleans and softens pvc chemically, that's what he's refering to.

I'm sure there's a reason (in terms of strength) that primer must be used to be up to code, but I don't think anyone has ever tested the two-in-one stuff, or has ever tested a pipe without primer.
Really, primer could only give a 10% strength increase, and we'd never know because no one here has tested it.

(Btw, ya never did check with the hardware store about the price of those pipe nipples spudgunwry:P)

Posted: Tue Nov 20, 2007 9:39 pm
by knappengineering
Just to clear things up, the pvc primer essentially softens the pvc in order for the glue to bond the two pieces into one.

Edit: _Fnord beat me to it! :(

Posted: Tue Nov 20, 2007 9:43 pm
by Maniac
oh i knew hat just couldnt understand it thx

Posted: Tue Nov 20, 2007 11:00 pm
by Lftndbt
I sell... Standard primer's, blue glue,green etc...
And the 2-in-1 Not the brand you refer to though....
Yeah plumber's think it's tops because....
1.One step, anything in one step seems to be a good option for them...
2.They have the piece of mind that they did prime and glue....
Just ask them, when they have used the 2-in-1, if they primed and then glued it.... They will say yeah! I did it properly... Primed then glued.... No you didn't you used a 2-in-1... you didn't prime then glue...
3. They just slap that on anything... dirty pipe, old, damaged...

In terms of Cannon devices, it would probably give you a similar rated seal...
Yet please be warned....
2-in-1 does not have the same fracture strength as a joint, which has been
~primed (which assist's the bonding process by making the pipe maluable and increases porosity) and
~glueing (which finishes the binding of the joint, by using solvent to infuse the pipe/primer/glue/primer/pipe .. If everything is done correctly, in affect you have "Melted" a joint into a solid pipe... To an extent..

This is something that has worried me in regards to "some" people's air cannons...

These joints are designed to withstand internal pressures not for weighted applications.
Eg. If you glue a 3ft, 40mm rated P.S.I pipe to a 100mm chamber...
Priming and glueing the joint would probably support the weight of the 40mm barrel...
Yet... If you use 2-in-1 It will VERY easily fracture the joint.. Possibly not from just the weight, but the first time sideways force is exherted onto the barrel... It will crack... Try it, I have.... Set two joints one properly the other with 2-in-1...
When done correctly if you try and crack the joint, you'll run the risk of snapping the pipe and cracking the plastic before it let's go...

The 2-in-1 cracks apart Very easily.... It almost appears that due to the 1 step the priming effect does not seem to penetrate the PVC..





Just my two cents...
Look forward to becoming part of your community...

Posted: Wed Nov 21, 2007 9:36 am
by psycix
Here in the Netherlands I cant find pvc primer and cement, we just use something thats called "PVC lijm" wich translates as "PVC glue"
Its a very thick clear liquid that has to be applied on both surfaces and then join the pieces together.

It works very well and is very agressive when spilling it on PVC to test it out :P
Dropping it on pvc and wiping it off will leave a mark on the pipe that some PVC has been eaten off.
This means its a good PVC solvent and that it will bond the PVC good.

Posted: Wed Nov 21, 2007 11:07 am
by Los Frijoles
I always use that purple primer stuff from home depot. As far as I know, primer helps the joint to have more strength.

Posted: Wed Nov 21, 2007 3:09 pm
by mopherman
Lftndbt wrote:

Look forward to becoming part of your community...
And we look forward to having you! You seem quite knowledgeable when it comes to this stuff. What profession leads to this kind of adhesive expertise?

Posted: Sat Nov 24, 2007 2:22 am
by spudgunnerwryyyyy
Ok, we have an understandment, plumbers love it cus u can use it in damp conditions and its easy because its only one part. We use primer and cement becuase its stronger and has a higher fracture point.

great.

Posted: Sat Nov 24, 2007 2:33 am
by Novacastrian
Bit off topic: Plumbers love the stuff because they can qoute x amount to do a job, without letting clients know that they are cutting corners.
Reminds me of a story i was told years ago about "rattler" guns and the railway industry.
In the old days men had to undo thousands of bolts by hand, then some smarty pants invented the air powered hammer wrench. They continued to qoute as though they didn't have this lovely new device, end result was them sitting around doing nothing for a great period of time. Whilst also getting paid as if they were doing a sterling job!

Just my 2cents :)

Posted: Sat Nov 24, 2007 2:53 am
by spudgunnerwryyyyy
Yeah that does make sense but blue glue aint as strong as primer ans clear cement.

Posted: Sat Nov 24, 2007 1:51 pm
by cdheller
this topic has a bunch of ways to go with it ,

I guess first would be that not all manufactures claims for using their product will pass a plumbing inspection.
just for copper glue comes to mind along with not using a primer with indicator dye.

Ive seem other plumbers rough in jobs red tagged (failed) for using clear primer.

if you read the (2n1)can or the website it states using primer may be required to comply with local codes.

nothing is stopping you from using primer and doing the job right.
its not a either, or case .

clear glue has its place but it,s not in the strongest joint category.


IMHO doing the final work in a finished building is all.
If your cannon workshop is inside you might save a lot of trouble going with clear

Ive (heard) claims that blue is stronger because it eats or etches into the pvc more ,Ive also heard gray is stronger because " the slower the set the stronger the bond"
Ive never heard someone say clear is better because it is thiner and has more air bubbles in it, pretty much the contrary.

choosing between blue or gray is more of a use and time thing

for repair work where time and/or wet conditions are working against you blue rules.
using primer in this case without letting it dry up adds to time until it can take pressure.

It probably does in other cases but aside from cpvc its not as apparent

gray in either medium or heavy bodied ,with or without being reinforced works better for in most systems construction .

Its approved for larger sizes, gives you more time to make your connection and adjust it ,and not being clear lets you see that you have actually put the right amount of glue on.


Sooo.. what works best for you?
your own experiments are usually a better plan than other peoples theory's

If you can get some spare glued up pvc joints and cut , break ,chip wedge and heat you'll find that one oft repeated myth fails real fast .
gluing pvc together doesn't make it one piece of pvc.

age of joint has a pretty big influence also

for what its worth

Posted: Sun Nov 25, 2007 2:19 am
by jimmy101
Well put cdheller. It really depends on what a person is trying to do.

One thing I would say though, is that a 2-in-1 product is probably not up to building codes in the USofA. Of course, an inspector would not be able to tell the difference between a properly primed and glued joint and a "2-in-1 with purple dye" joint but it is generally not a good idea to try to fool an inspector.

There have been many discussion on what is in PVC cleaner, primer and glues. The spudwiki pages have listings of the various ingredients. Since primer and glue contain different things, I would think that it is not possible to combine the two products into a single container and still retain the capabilities of the individual products.

Posted: Sun Nov 25, 2007 3:42 pm
by 666lucky693
i thought that the glue and primer chemically reacted to completely bond the pvc into almost like one piece so if you mixed them both together it would destroy the propertys of strength that having them separate makes so it would have to be bad

and i've never tried the purple primer i only found the clear stuff