What do you expert scratchbuilding folks use to fill in holes and thin spots on plastic, resin or fibreglass body shells? What do you use for building up and re-shaping body contours? I have never had much success with 2-part putties like Milliput or Tamiya Epoxy Putty. They seem to dry out very quickly in the package and refuse to blend together well with simple finger kneading. The 1-part substances like Tamiya White or Polyester putties shrink so much as they dry that things you thought had been filled appear again the next day.
Post by Andrew Rowland on Feb 24, 2017 2:23:23 GMT -5
Stewart I seem to have your exact same experiences....
The tiny blemishes and holes in body surface I fill with superglue. This was a Chris idea and it works well. You need to take care when sanding in as the resin tends to be softer than the glue though!
For forming I use the Tamiya white putty. The shrinkage is annoying but I find that putting plenty on and going back after say 8 hours and applying another layer before the first is fully set (but has been subject to the dreaded shrinkage) works well as it has now become quite predictable.
The reason I use it is because the grain is so fine that you can achieve seamlessness while milliput I find I can aleays see the grain between the body and the fill!
That's just my experience. I have to go through the whole painting, filling sanding procedure several times with careful washing and drying in between. This part of the build is the bit I like least and it takes me about 10 days!!
Hope to learn othher techniques when people add their experiences...
Post by David Mitcham on Feb 24, 2017 2:43:13 GMT -5
I've tried various fillers etc and all have some issues. Currently I use mainly Tamiya light curing filler which works well with minimal shrinkage but you do need good daylight, preferably sunlight, to get it to cure. In the right conditions it sets very quickly and can be sanded almost immediately. It is difficult to source - I got mine on e-Bay from Hong Kong or somewhere out east so it took quite a long time to arrive in the UK. I sometimes use Humbrol filler for small areas and I find that works pretty well too.
Hello, I use two component putties used for finde work on normal cars which works great. For fine scratches and final detailing Tamyia fine filler which is intended to be used with airbrush. I use this filler with a normal paintbrush in the areas where I need it. Both methods are fast drying and very reliable. Best regards, Thomas
To build up and re-shape body contours, fill in holes and thin spots on plastic, resin, or fibreglass base materials, I use a structural material to augment the base material. The structural material could be a plastic, a metal, a composite, etc. The key characteristic is that the structural material must possess its own structural integrity and rigidity.
After preparing the piece of structural material, it will then be attached to the base material with a gap-filling adhesive or adhesive filler, such as epoxy, putty, etc. The adhesive is used only to join the materials (and fill very small gaps). The structural material itself forms the new structure, not the epoxy or putty.
I've found this method to reduce problems such as shrinkage, incomplete curing, lack of integrity, etc.
routinely use white Milliput on patterns. It does not have good initial adhesion so I roll it in my hands to thin "sausages" and press them (hard) into place. I do an initial rough shaping with a water wetted fingertip, carve off major excess with a sharp (wet) knife and then repeat the finger smoothing process. Allow it to harden for 24 hours and then sand.
A package lasts for about a year if it is carefully wrapped in plastic film after use
For modifications of a final body, i.e. injection molded, Milliput is very heavy for extensive use. I typically do major structural additions by adding a piece of shaped balsa and then skimming with Squadron Green putty to fill seams and grain.
Post by Chris Wright on Mar 24, 2017 19:20:23 GMT -5
I use Alan's method, and since a lot of the cars I make are resin, (well they all are) I collect the resin dust from other modifications in a small jar (I started this to keep my work area clean because on COPD). And always where a mask.
Then any imperfections I fill with a pinch of the dust, and put a drop of viscous super glue on top. Sand away excess, and you'd never know there was once an imperfection there. Plus because it's the same material, I don't get that "shadow" efect a month later. (you can make out the outline of the repair.)
On a plastic car, I use plastic dust.
On thin spots I reinforce from the inside with glass fiber cloth and superglue.