Thanks for the input. Most of my problems are little dings. Do you wick it before painting? And do you need to use watered down filler before you wick it, or is that smooth enough?
I really like that rocket you are working on. Forgive me if I'm wrong but that looks like a Titan-III.
Andrew
Yep... that's the Dr. Zooch Titan III MOL... it's a REALLY slick kit! There's a build thread around here on it...
https://www.rocketryforum.com/showthread.php?t=4418&highlight=Titan
You really aught to check out the Doc's stuff... it's WAY cool and VERY good quality and very fairly priced...
https://www.drzooch.com/rocketgallery.htm
I've done a bunch of Dr. Zooch build threads... and still have a lot more to do, but ya know how it is around the holidays...
Anyway, here's what I do...
First thing when I start on the kit, I test fit the nosecones/transitions, and if everything goes together right (99.9% of the time) I go ahead and CA them. Hobby Lobby sells little (and bigger) bottles of CA in three thicknesses-- pink is 'water thin', yellow is medium, green is thick. Always use the 'water thin' for hardening as it 'soaks in' to the balsa and turns the outer layer into something much like a composite material, sorta like fiberclass or carbon fiber (of course nowhere NEAR as tough as the real thing, but the CA DOES glue the wood fibers together efficiently and leaves a resin behind which strengthens the material, just as other composite materials do) I use the tip of the bottle to 'color' the CA onto the part, just like you'd 'color' it with a magic marker tip. I try to keep the CA off the shoulder of the nosecone, because it will slightly increase the diameter and make it fit too tight in the tube, requiring it to be sanded down pretty good. CA tends to raise any loose fibers and sawdust present in the pores of the part, even if wiped REALLY clean, and so the part will be slightly 'prickly' when the CA is cured. I give the part a nice sanding with 220 grit paper and that slicks it right down with about five minutes of work, usually. Be sure not to glue your fingers to the nosecone as your treating it-- I usually hold it horizontal with the tip a bit lower than the shoulder to let any excess CA run towards the tip (get a thicker coat) as I apply it. Do this outside because the CA gives off some rather strong fumes that will make you tear up and burn your nose if you're indoors, and I usually stand crosswind so the fumes are carried away on the breeze, not into my face, or if the wind is behind you, the breeze can whip around you and still waft it in your face. It's not a BIG deal but you DO want to minimize/avoid it. It's like ammonia fumes-- not pleasant but not a BIG deal...
Anyway, you can see the CA as it's applied to the wood-- it's clear, but it turns the wood a slightly darker color as it goes on (as most liquid things do on solids) and once you've got it applied over all, rotate it around and look for any lighter 'dry spots' and daub them with a drop of CA if you see any. I then set them aside on a piece of cardboard to cure, which is usually completely done in 10 minutes at most. IF any CA happens to run down, it CAN glue the nosecone to the cardboard, but they're easily popped off.
After I've sanded with 220 grit, I then brush on Elmer's Wood filler, thinned in a baby food jar with a few drops of water or so and worked in with a 1 inch paintbrush until it's about the consistency of hot dog mustard, or maybe a TOUCH thinner... not watery by any stretch! I brush that on the upper parts of the nosecone, keeping it off the shoulder, and set it aside to dry. Usually within 30 minutes it's plenty dry to sand. I sand 95% of it off with 220 grit paper, and if there are any visible 'low spots' or grain showing, I brush on a bit more in the affected areas, let dry, and sand with 220 grit. Then they're ready for primer, usually Walmart Colorplace 99 cent stuff, put on in 2-3 light coats, allowed to tack up 10-15 minutes between coats, followed by a little heavier coat, allowed to dry an hour or two at least, and then sanded with 220 grit. Once sanded down thoroughly, if there is any imperfections showing (low spots, grain, etc.) I may hit it again with primer if necessary, if no spots look bad, which is 75% of the time, I go ahead and switch to sanding with 600 grit wet/dry paper, dipped in a bowl of water and shaken/daubed off on a towel, using what I call "damp sanding"... sometimes I wet the tip of my finger and leave a drop of water on the surface, but rarely is that necessary. I slowly rotate the part in my hand, sanding in small circular pattern, working my way toward the tip. The damp sandpaper should leave a 'sanding mud' of sanded-off primer particles mixed with moisture from the paper behind. Every few minutes I dip the paper in the bowl, work my finger over the grit to release the primer particles, and daub the paper on the towel lightly before going back to sanding. I usually wipe the sanding mud off the part with a damp paper towel at the same time. Once the whole surface has been damp sanded, wipe it down thoroughly with a damp paper towel to get all the sanding mud off, wipe it again to make sure, and then wipe it off with a dry paper towel. Then inspect it by looking up the cone like a gunsight, holding it up so the light from a lamp or window can 'glint' off the side of the cone, rotating it slowly, watching the 'glint' of light along the length of the cone-- if the glint is smooth and uninterrupted, unwavy or not showing any specs of grit or dimples or whatever, the part is ready to paint. IF not, another primer coat is called for. 90% of the time it's not needed; the part is ready to paint, and will look identical to a plastic part from the shoulder up...
As I said, they're not COMPLETELY bulletproof-- I've gotten a couple MINOR dings on the fairly large transition on my Dr. Zooch Discoverer Thor (there's a build thread on it to, in the archives I think-- use "search" above if your interested-- it's a neat kit too!) but it's had a few hard landings... I had the nosecone and "Agena" tube pop free of the transition and free fall from altitude onto hard dry ground and was found with dirt stuck on the tip from the impact, but otherwise completely undamaged! So, it DOES work...
Hope this helps! Later! OL JR
