I am getting ready to build some wood kits that I have and I have some questions.
Glue recommendation. I have seen canopy glue, wood glue, Aleens and CA type. What have peoples experiences been?
Paint warpage. I have seen coating both sides with a primer or acrylic before starting; painting both sides after wall completion into an object; and no need to paint both sides. What are your experiences?
Jim
I do a lot of scratch building and I’ve had very good luck using Aleen’s Wood glue and prefer it over any wood glue I’ve used in the past.
As for painting I’ve never primed wood structures, I prefer using satins or light washes of Acrylic for an aged look. Thin wood will warp easily so to prevent that I use internal cross grain bracing.
Mel
Modeling the early to mid 1950s SP in HO scale since 1951
My Model Railroad
http://melvineperry.blogspot.com/
Bakersfield, California
Used to only use ACC but now mainly white glue due to the tack taking just a bit longer but that means more working time, sometimes you need that. Never prime and only paint one side but I brace as much as possible, buy lots of extra strip wood.
I use Titebond, but other wood glues should work also.
Prepainting both sides with water based paint cause warpage, but not so badly that it could not be straightened out with some bracing. I plan to try spraying a sealer on my next kit before starting.
Good luck
Paul
If you prime big panels first then warpage is less of an issue when colors are applied. I tried several rattle can primers and I found Duplicolor Primer Sealer worked best. Less solids than other primers and it goes on nicely. I use it only on large panels.
Lately I’ve been airbrushing my structures with acrylics. Less messy, less wasted paint and better control of where the paint goes. If not primed the water-based paint will warp big panels but I paint both sides and once tacky-dry then sandwich the panels in wax paper between old college text books. When completely dry they are perfectly flat. I’ve not used any primer on the last couple of kits and had no problems with warping using this method.
I paint all the parts before popping them out. Then touch-up with a brush as needed. I just tape off the parts that are different colors. Usually the parts are sort of grouped in logical colors so its not too hard to do.
As mentioned extra bracing is a good idea especially for large structures.
Titebond for strength, white glue for most everything else and canopy glue around windows. Excess Titebond dries yellowish so I use it sparingly. White glue and canopy glue dry clear and almost invisible.
Would Testor’s Dullcoat be a good sealant before applying acrylic brush paint. Also I’m considering the Krylon clear coat that I use for making decals. After not having assembled a wood kit in years, I have just done two but I was using rattle can paints for both interior and exterior walls. The next one I will want to custom blend acyrlic paints and haven’t decided whether to use a gray spray can primer or one of the clear coats.
The Poly Vinyl Acetate (PVA) glues, which includes yellow carpenters glue, white glue, Elmers, Titebond, and Aleen’s Tacky glue will make a wood bond as strong as the original wood. You need to make a good tight joint, no gaps, clean surfaces (no paint) and you need to clamp the joint overnight. Done long grain to long grain, you can get a joint as strong as the original wood.
Cellulose cement (Duco, Ambroid) is strong enough for many things, detail trim, window frames and the like. Major benefit is a real quick dry, a minute or two to adequate strength and no clamping required.
I don’t recommend the urethane glues (Gorilla Glue) for model work. The stuff foams a little bit, squeezes out of the joint and needs trimming to look good.
As far as warpage goes, the big thing is to paint BOTH sides. If you leave one side (the inside for example) bare wood, the bare wood will absorb moisture from, or loose moisture too, the air, whereas the painted side cannot. If one side has a different moisture content than the other, you have a warp.
Water based paint will warp wood more than solvent based. If the top coat is gonna be water based (acrylic) I like a primer on the bare wood to reduce the amount of water soaking into the wood. Just about any solvent based finish or paint works. Shellac is good, it dries to recoat in a few minutes. Rattle can auto primer or clear coat works. Varnish works but it takes overnight to dry.
I assume that thin sheet wood (1/16") is gonna warp unless I glue strip wood stiffeners to the inside of the panel. You can never have too many stiffeners. If the kit doesn’t come with stiffeners, some 1/4" or 3/16" stripwood from the hobby shop will do the trick.
For laser cut structures I’ve used gray rattle can automotive primer and it works fine. I usually apply a second coat after the first has dried. If you want to model distressed paint, the gray primer coat can also serve as the colour for the exposed aged wood.
Interior bracing is strongly recommended. Seasonal humidity changes can wreak havoc on a model that started out straight. I have an icing platform that is as good a humidity meter as any.
If you want to detail the interior some thought should be given as to the location and sizes of the bracing. It can be disguised as ductwork for example, or hidden under interior details like shelving or desks/file cabinets. It doesn’t all have to be square stock. A false floor can do the same thing for the bottoms of the walls and all you will need is exterior door sills to hide the rise in floor height.
Interior bracing isn’t just for wood kits. Scratch built styrene structures need it too.
Dave