Anyone use Weld-On 4 for assembly?

Never tried it on models myself. I also used to use it for building acrylic aquariums. Be careful with how you apply it as its a solvent cement meaning it slightly melts the plastic. It melts the two halves together and joins em that way. If you get any on an area that its not supposed to be on get it off quick because like I said it starts to melt and soften the plastic immediately. And when you do remove try not to wipe but dab it off. Wipping it across will leave an unsightly scar in your plastic

...right ..ok...did you read the post?  ... weld-on 3 is 65 % MEK ....10% actetone... it is stated plainly on their website.

 here's a break down of some popular cements.

*Testor's liquid (glass bottle) = MEK + ethyl acetate 

*Ambroid, pro weld = methylene chloride 

*Tenax = Butyl Acetate 

*Weld-on  ( styrene effective products from them) = MEK  + acetone

Mike

Check at TAP and see if they still carry Methylene Chloride.  I've used it for years and I do believe that its is the exact same thing as Weld-On 3 (in fact I use two old Weld-On 3 bottles I fill w/the Methylene Chloride for use at my modeling desk).  At one time you could get it in gallon cans (lasted 3-5 years) and was a heck of a lot cheaper than the Weld-On 3.

I've used a lot of Weld-On 3, but you've got to be careful with it.  It's a lot hotter than Tenax.  From mixing and matching solvents over the last few models I've come to the conclusion that Tamiya Extra Thin is within a hairs breath of Tenax in terms of heat, and that WO-3 is nearly twice as hot as either.

I now only use the WO3 for big joins like wing roots or fuselage halves when I can put the stuff down from inside.  For surface capilary action joins I much prefer Tamiya or Tenax.  

Yes I'm using it but its not the same at all.

Thanks LH and yes I am very proud of my soon to be USMC Drill Instructor son.  I think I will try some Weld-On 3 since from what I understand MEK is becoming real hard to find these days. I have a gallon of lacquer thinner in the garage as well and just gave that a try. It doesn't work that well.

Guess I will get the Weld-On #3

If Tenax 7R is your favorite poison, then off the shelf, Weld-On 3 is your best bet.

Most of the plastic welders are MEK, Acetone, Butyl Acetate, Methylene Chloride or a combination of same. MEK is probably the safest, but don't drink it. LOL!

I stopped chasing the dragon and now use a custom blend of 60% MEK, 30% Acetone and 10% Ethyl Alcohol. It's fast, cheap and will melt most plastics that I have come across in modeling.

Most Lacquer Thinners are nothing more than blends of MEK and Acetone.

Congrats on your son making D.I. I bet your one PROUD POPPA!

NOW FINISH THAT LAV!!!

From what I have read in researching it Chuck it seems the chemicals in Weld-On 3 and Tenax are arguably worse than MEK. Interesting.

MEK is nasty stuff, so be sure to wear a vapor respirator if you are using it.  I have found it has been pulled from the shelves in all the hardware stores around here (Colorado) and suspect it is another crusade by the "Green Wienies" who seem to have made this state their HQ.  Now I can only find "MEK Substitute" and I have no idea what it is.

Not really sure Mike but if you do use Weld-On, make sure you take the precautionary measures as from what I've heard it is some very nasty stuff to inhale or get on your skin. I used to use it all the time to build acrylic aquariums but always used it in an open garage.

Thanks Eric. If they contain MEK why don't people just use MEK which can be found at any hardware store? Is straight MEK too hot? It looks like from the MSDS sheet on IPS' website the Weld-On 3 is 65% MEK and 10% Acetone so I wonder if the other 25% is something that makes it less aggressive?

I have. Seems to work as well as any other liquid cement since I believe its the same thing, MEK.

Sorry, that should have read Weld-On 3