De-bonding styrene parts?

[PAL_Houston]

I acquired some assembled models that are in need of "editing" and I need to either de-bond some of the parts or cut them apart.  Before resorting to the knife, does anyone have a solvent that will de-bond styrene parts? 

Thanks for your input.

[peteski]

If they are "welded" using liquid cement which actually dissolves and welds pieces together then there is nothign sans mechanical ways to separate the pieces.

If they used super glue or tube glue then there are chances that the joints can be weakened.  IIRC, paint thinner (turpentine) applied to the tube glue joints might weaken the bond. But it might also attach the plastic.  There are also super glue debonders out there but many of them also attach plastic so you need to be cautious.

If it is epoxy then I don't know of any chemical way to weaken the joints but if the plastic was not perfectly clean before assembly the joints might hust come apart due to being fairly week due to surface contamination.

There are all sorts of anecdotal ways to break apart joints (like wetting the model and freezing them) but I don't this is something that will work.

When I assemble my models I do it really well so there is no chance of cleanly taking them apart. But that also works against me when I find myself in a situation you're in. 

[DKS]

When I assemble my models I do it really well so there is no chance of cleanly taking them apart. But that also works against me when I find myself in a situation you're in. 

+1

Methinks you'll need to resort to a knife, or a razor saw, which might offer a little more control.

[PAL_Houston]

Well, I went ahead and flowed some Ambroid Proweld along the inside seam, and that softened the joint some -- enough to get a chisel-point into the joint.  But you guys were right -- the separation was mainly mechanical and I basically destroyed the doors I was trying to remove, but that's OK I can live with it.

[havingfuntoo]

Did you try freezing them, some glues will let go under such conditions

[peteski]

I guess that Paul didn't freeze them as I mentioned this too and he passed on that method. 

[PAL_Houston]

I guess that Paul didn't freeze them as I mentioned this too and he passed on that method. 

No, but I didn't try to get all of the doors off either.  What the hey?  It is going into the freezer tonight and maybe I will have a report for you tomorrow....assuming my darling bride doesn't remove it from the freezer prematurely, thereby defeating the purpose of putting it there in the first place. 

[pnolan48]

If the joint is welded, you could try scoring one side, then snapping, the same way you would score and snap styrene sheet. That has worked fairly well for me with the thinner styrene I use for scratchbuilding--kit styrene is usually thicker.

[PAL_Houston]

No, but I didn't try to get all of the doors off either.  What the hey?  It is going into the freezer tonight and maybe I will have a report for you tomorrow....assuming my darling bride doesn't remove it from the freezer prematurely, thereby defeating the purpose of putting it there in the first place. 

Well, freezing it in hopes of making the bonds brittle so the bonds would break did not work in this case.  I think this is because the parts were "welded" by the glue. 

The "score and snap" method would work of course, except that the parts I wanted to remove are on the outside of the structure, so I have had to remove what was left bonded by the mechanical method anyway  (I used an old #11 X-acto blade ground down to a chisel point).  I then had to "restore" the underlying surface (brick) which I did by softening it with ProWeld and then re-scoring the mortal lines.  I doesn't look so good as the original, but some sanding, a couple coats of paint and some signs will probably hide surgery well enough....for the back of the layout