Patience

Scale-Coat has been bought and is hoping to be back in production around the end of July, so hopefully they can still meet your needs.

Desired finish

If you are trying to make wood not look like wood, then a sanding sealer is needed. Is this a representation of a wood caboose or a steel caboose? I've built several wood cabooses out of wood and never used a sanding sealer. I also tried to make a wood roof look like tar paper by using sanding sealer and never was able to hide the grain of the wood.

"Sanding Sealer.?"   

You might try a model airplane shop, they used to use sanding sealer on wooden planes( don't know if anyone builds them these days though?) otherwise a small can of shellac would work. Try a craft store perhaps?  If nothing else turns up I'd just seal it with varnish or paint and not worry about it as most models don't spend a lot of time in high moisture locations. The metal parts should do fine with primer and paint and if you seal the wood before assembly you should be able to then airbrush the whole thing with no problem. (other than the unforeseen problems that always seem to pop up that is ).......DaveB

I discovered on another

Wood Sealing

The caboose is an old wood 1000 series NKP type with "board" sides. I was considering just painting as I was thinking a sealer would give it a "glossy look" when painted which is not the look of most of that type in the yards at Ivanhoe Road or 55th street. The wood ones were often faded, chipped and "shop worn" and were gradually replaced by steel models that were "shiny."

Sanding Sealer

Try this link: http://rrmodelcraftsman.com/extraboard/cm_howto_stripwood.php

Jerome-OKC

You could use this............

...........for sealing and it's not too expensive.

http://www.amazon.com/gp/product/B00133Z9H2/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1944687642&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B000SKZT9Y&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1E02P354E82KF8XNMKN1

Here a quick video about the whys of sanding sealer.

Peter

Sealer

One of the posts "sealed" it! The humidity varies in my basement layout and sealing the wood will prevent cracking and keep the caboose from falling apart. Many thanks for all your replies; this is where I always come to for solid advice.

Brew your own

For model aircraft i used to use 50/50 thinned varnish with a teaspoon of Talcum powder mixed in. Probably the white powder he mentions in the video

You should be able to buy

You should be able to buy sanding sealer in the paint department of your local home improvement store.

An alternative

There is a product available for artists  that is an all purpose sealer made by Jo Sonja. The blurb reads: Jo Sonja All Purpose Sealer is a pure acrylic medium with remarkable adhesive powers. It is a durable and versatile surface sealer that can be used to seal most surfaces in preparation for painting. Included are wood, tin and other metals, glass, unglazed bisque, terracotta, cards, paper and fibreboard. Mix with colour for a one step base coat. A 250ml (8.5 oz) bottle in Oz is around $15.

Kevin in Queensland