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Hi peeps

Any tips on debonding abs cement - thick and crystaline, I assume it is abs cement

Did a search of the site with no results

Restoring a Wild Willy the body is not painted but I need to get all the front fidly bits apart for painting

I have some cyano debonder but warning says it may attack some plastics, and not sure it will even do anything

Thinking of brake fluid / caustic soda / grafitti remover / denatured alchohol ?

Some help please

Terragi

Good luck. The only solution is sanding, syntofer, sanding primering and painting. WW is a super funny car.

If it's CA glue, that could be hardened when it's boiled and give a better chance of removal.
Just beware your plastic doesn't melt...
Solvents will probably attack the good bits as well.
Usually it comes down to sanding (a lot) though...

I think the problem with traditional poly glue is that it melts the plastic, and as the solvent evaporates, the plastic hardens & effectively leaves the two bits welded together - so nothing like CA which remains between the 2 bits & holds them togther by grabbing on to microscopic irregularities on the surface - there's nothing of the original poly glue left behind to debond.

It's quite a porous weld though, my experience with De-Solv-It grafitti remover has been that as the remover softens the plastic, it gets into the pores & can loosen the bonds. Only about 1/2 the time though - half the joints will pop apart with no extra damage, the other 1/2 will bend, stretch, crack, shatter, etc etc meaning a lot of extra remedial work.

Also - I think it came up quite recently - the Strine formualtion of the product with the same name has a completely different formulation


So ... what stingray & edou said really, if you really want to get it apart.


I'd ask though, just what fiddly bits do you need to remove to paint separately? The only bits I can think of that should have been glued are the radiator & the headlamps... TBH I'd spray the whole thing with white primer, mask the headlamps as well as possible, spray the whole thing green, then very carefully brush paint the headlamps after, the radiator is probably best done by giving it a heavy wash with watered down black acrylic with a brush through the bars of the grille.

Depends how old the cement is & how well it was done -

If the glue's new (Less than a week), a long soak in hot water with lots of washing detergent will soften it enough that it will break at the bond line when you flex it.

If it's 1980s model glue & wasn't done particularly well, give it a gentle flex & listen for cracking noises coming from the joint. If it does, it should break along the joint-line, but keep an eye out for any white stress marks in the parent plastic (& stop if you spot any). Sometimes scoring a line in the cement at the joint line before you start can help too. If that doesn't work, try a soak as above.

If the cementing was done well & is old, sorry but you don't stand a chance. A "good" bond will have melted & blended the plastics at the joint face, to form a proper weld, similar to welding metal, & any force will always break the material NEXT to the joint line, not on it, ie if it's done properly, there is no join, both bits of plastic become one & there's no layer of glue to dissolve.
HOWEVER, this is quite unlikely as only very few people ever degrease & prepare the joint faces before cementing or keep pressure on the joint during the process to complete the bond/blend/weld. The clue will be in how well the rest of the components have been assembled

Jonny, I don't understand why you separate the front grill to paint a WW body.
All my ABS bodies are painting after assembling. For me it has a better finish and no glue marks.

Cos the grille looks better if the radiator behind it is a different colour

stingray-63 wrote:

Jonny, I don't understand why you separate the front grill to paint a WW body....

I'm saying I wouldn't, for one that's glued and not damaged.

Same here - if it puts up a fight & won't come apart easily, give up before you hurt it

Alwright Jonny