Materials overview

Now lets talk primer and putty. My choice for primer is a high-build primer like the Dupli-Color Filler Primer shown here. This fast-drying Lacquer primer comes in both red and gray. It builds up quite thick very fast, so it's very easy to fill scratches, very shallow low areas and dings, brush strokes, etc..

As for putty, I use 3M brand Acryl-Green Spot Putty. This stuff is almost identical to the Squadron putty if you've ever used that. It's a little more durable as it is intended for auto body use versus plastic modeling. It dries very fast and sands very easy.

It will shrink and crack a little if you put it on too heavy. This is really only intended for very shallow fills so don't use it like Bondo. This will help you get areas feathered out well, like the edges of fillets and fairings, but don't use it to "build" a fillet or fairing... just to level and feather it.

Before getting too deep into this, I'll just explain that I hit each side of all components with one decent coat of the Filler Primer. It dries in about 5-10 minutes, so this step goes very quickly.

Canopy and control surfaces

This time I'll start with the canopy (rear section). With the open glass areas masked out and primed, I go ahead and sand the daylights out of it until I've removed virtually all the primer. All that will remain in primer are some wood grain lines, brush strokes, low spots and other types of areas that the primer will stay lying low in. This levels and flattens out a large portion of the areas you are looking for and shows you where the remaining ones are.

Very slight/shallow lows are already filled by the primer, but deeper, more stubborn irregularities will require a treatment with the 3M spot putty. Look for the areas that the primer remained after sanding and you'll find the low areas. I apply the spot putty in one thin coat and let it dry. It's dry to the touch in about 10 minutes but not ready to sand for about an hour.

Again, I sand aggressively until I get the putty as smooth and flat as possible. You'll probably already see some areas that still need some more work. Remember, we're trying to blend the plastic canopy into the balsa turtledeck, so this won't be a walk in the park to feather out. I go ahead and shoot primer again, then sand again and I see what remaining areas need more work.

A little more putty and sanding and I'm just about done. The last few little blemishes remaining can be seen without even shooting primer again. A dab of putty on your finger and you can make them go away with ease. Give it all a good final sanding with the fine grit sponge and you're done.

Moving on to the control surfaces, I found that the primer coat pretty much filled any remaining weave and revealed virtually no spots to be puttied. Just a few small ones to fix and I was good to go. The pic at right shows how smooth the finished result was on one of the flaps.

The wing

OK, more of the same here on the wing. The bottom side was a little more complicated as there were a lot more obstacles to work around (wheel wells, flap bays, etc.) but it still went pretty easy. Actually I had a little more trouble on the top side as I had a couple stubborn low areas that I had to work pretty hard on.

The biggest hassle here is the mess from the primer dust. You really pile up a lot of it when you do this type of work and it gets everywhere. Fortunately it's pretty easy to clean up and washes right off of anything. You'd have a mess like this regardless of what primer you use, although I I have to admit that this red dust shows up a lot worse than the gray primer dust does!

While it may "appear' that I've really piled a lot of putty onto this wing, that's really not the case. For the most part, what you see in putty on the wing is very, very thin and feathered. Actually, I weighed the wing before glassing and after putty, just like I did on the fuse. The result was just over 5 ounces of weight for the whole process.