Scenery getting you started
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Inactive Member
Polystyrene
[user=1632]BCDR[/user] wrote:If you note back to the original post that mixture of water to PVA is for mixing with the pollfilla, it as I state, creates a nice hard shell of pollyfilla not a crumbly surface.[user=1938]The Q[/user] wrote:Hi Kevin,just A note, I've just updated my first post as I managed to mix 1/3 water with 2/3 rd water. It now says 1/3 pva with 2/3 water…
Dangerous waters here. PVA starts to behave rather funny when diluted too far. Loss of tensile strength for one. The recommended dilution for woodworking is 95:5 PVA:water v/v. Most applications of PVA in this hobby do not call for a lot of tensile strength, my own experience is that 75% PVA is around the limit for good adhesion. Gluing bits of styrene needs the neat stuff, and works best if the surface is roughed up a bit with some sand paper.
Big problem with styrene-based foams is that decent compression during the tack stage is normally not possible. Best approach is to glue the flat piece, weight it down, then cut/carve when attached.
For what you are doing a chunk of balsa would probably do just as well. If the styrene you have is the light, white material found in packing that compresses between thumb and finger I would bin it. You need the pink/blue/green one meant for insulation.
Nigel
For gluing pollystrene to the baseboard I use the PVA straight…
Now I've finally started a model railway…I've inherited another…
Posted
Full Member
Missed that one. Must try it. As I said, pva and styrene foam works best with a rough surface and neat glue, plus some compression. Best to use the correct adhesive for hd closed cell foam.
Nigel
©Nigel C. Phillips
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