Jeff396

My Feedback: (1)

Hi all,

I've finally reached the step I've dreaded on my Midwest Pitt's. The plane has an ABS turtledeck which I've blended into the vertical stab with some hobbylite. I have tried to cover with monocote but the end result was unacceptable. Now I'm thinking of painting with the spray cans that match the monocote. My question is will simply priming the plastic, filler and wood with the ( I think it's top flite paint) spray primer give me a good finish or do I have to prep the wood and filler differently than the plastic?

Jeff

LuvBipes

My Feedback: (4)

Jeff the only prep required for the PLASTIC parts before priming, is to remove the gloss with 400 grit sand paper. Same for the filler.

As to preping the balsa, well, volumes have been written on the subject. One technique that works acceptably, though not a "show" quality finish is the following.

prep the plastic and filler areas as described above then fill/sand the balsa down to 400 grit.

Now, MASK the balsa area on the fin/stab that will NOT be painted (ie. the areas that will be covered with monokote later). Shoot the primer coat and remove the mask. Next, feather the line betweeen the balsa/primer with 400 grit to remove the ridge.

Now, cover the balsa areas with monokote JUST coming up the the primer/balsa separation line. Next, RE-MASK the monokoted areas about 1/16" INSIDE the monokoted area (yes, I know this gets tedious, but you're almost done!). This way, the color coat will extend slightly over the monokote, thereby sealing the edge.

Finally, shoot the color coats on the filler/plastic areas and remove the mask before the paint dries completely.

I'v used this technique on 2 planes with very acceptable results. Getting a decent paint match is of course critical to getting good final finish.

Have fun.

ramcharger

I use the plastic turtle deck as a form to build a balsa one. I have built 3 Sig Kougars and a King Cobra and never used the plastic supplied turtle deck. Heat from a covering iron will warp the plastic turtledeck and a painted turtledeck on a Monokoted plane looks crappy.

Jeff396

My Feedback: (1)

Ramcharger,

Of course you're right and I had kicked the idea around a bit. Problem is that I haven't built a kit in 20 years and then it was only a Kadet MKII and gentle lady. This is the first kit I've attempted that just came with two big sheets and some writing here and there. I was a little aprehensive about deviating from the directions. However, this will be the last plastic turtledeck I use.

Luvbipes,

The portion of wood vertical stabilizer that sticks up over the turtledeck is very small. Maybe it's two inches high at most. It seems a bit silly to monokote any of it considering its size. Would there be any problem with using the same primer on the wood and painting it like the plastic and the filler? Would the primer do a good job of sealing the grain giving me a smooth finish?

Jeff

LuvBipes

My Feedback: (4)

Jeff, unfortunately primer alone won't fill the grain in balsa. Here's what I do:

1) apply 2 coats of 30-40% thinned NITRATE dope (available from Brodak or Sig) to the balsa sanding after EACH coat w/ 320 or 400 grit to remove the fuzz.

2) In a separate jar, mix up a mixture of baby powder (use real TALC, not corn starch) and NITRATE dope. This home-made filler mixture should be of the consistency of a thick milkshake - not a paste, but not runny either.

3) apply this filler to the balsa areas and after dry, sand progressively with 180/220/320/400 grits sand paper.

4) now look at the surface against the light at a shallow angle. If the grain is still visible, apply another coat of filler and sand again.

5) Once you are satisfied with the surface quality, shoot the primer, wet sand when dry with 320 or 400 grit and finally shoot the color coats.

Jeff396

My Feedback: (1)

Thanks, I'll give it a go.

Jeff