#31
|
||||
|
||||
I actually prefer to use water-based sealers on balsa nose cones rather than dope. On balsa fins, it's the other way around; dope is the better product for them. I have specific reasons for this. I prefer to do as little sanding as possible on the actual surface of nose cones. The reason for that is because I buy cones that conform to specific shapes, and I have had too many regrettable experiences that involved sanding just a little too much in spots, causing the nose cones to be misshapen. When you use either dope or CWF you are sanding down to the actual wood, and I just prefer to not do that. Using water-based sealers like Delta C. or Pine-Pro there is much less of a risk of over-sanding, especially with the method that I use. I don't begin sanding water-based sealers until after the second or third application, at which point there is a good protective layer over the actual wood. The wood is well-sealed in preparation for the next step: wet sanding. The nice thing about using WBSs is that you can wet-sand them; in fact, I almost never dry sand them. Wet-sanding produces far and away the smoothest, most flawless surface finishes, and does so with surprisingly little effort. I have never misshapen a cone during wet-sanding, and I doubt that it is even possible to do so without a great deal of deliberate effort. I also prefer to use this type of sealer on balsa transitions for similar reasons.
With fins, I have different needs and priorities. I am almost always sealing and sanding flat fins, so inadvertently misshaping them by over-sanding is not an issue. I don't like to put any product that contains much water onto bare fins due to the risk of warping them. A combination of dope-based fillers and sealers is the perfect solution; it provides all of the positives and avoids all of the negatives. Dope is particularly effective on flat surfaces, or at least it is very easy to use on them, which makes it much less of a hassle to put in the work that is necessary to get mirror-smooth surfaces. Dope seems to have the incidental benefit of making the surface slightly harder, too. So in the course of building many of my rockets I end up using both types of sealer. Each type has unique qualities that make it particularly useful for certain tasks.
__________________
Mark S. Kulka NAR #86134 L1,_ASTRE #471_Adirondack Mountains, NY
Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity
|
#32
|
||||
|
||||
Quote:
Good idea. I will have to try that. Bill
__________________
It is well past time to Drill, Baby, Drill! If your June, July, August and September was like this, you might just hate summer too... Please unload your question before you ask it unless you have a concealed harry permit. : countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ; Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding... |
#33
|
||||
|
||||
Quote:
If you use the right solvent, Aero-Gloss, SIG, and other sanding sealers are super-easy to clean up. I keep lacquer thinner in a small bottle, and dunk my brush a couple times, then wipe with a paper towel. The small bottle gets periodically topped from the gallon can. And I've used the same brushes for years. I keep the sanding sealer, solvent bottle, and several size brushes in a small tote for finishing, so everythign is dedicated just to finishing. The brushes and solvents never get used for anything else, such as touch-up painting. I dislike water-based sealers for balsa, for the same reasons I refuse to use water-based finishes when I do woodworking. The wood can easily swell, and the finish is just plain inferior. Safer? You bet. But I ventilate my shop, or use these products outdoors. I'll concede that if I had started finishing years ago with water-based products, I might have learned the required techniques to get great results. But I've been doing woodworking for 40+ years, and I figure why mess with proven (for me) techniques.
__________________
Lee Reep NAR 55948 Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor In the Paint Shop: Nothing! Too cold! Launch-Ready: Farside-X, Maxi Honest John, Super Scamp |
#34
|
||||
|
||||
Quote:
Glad to hear it... BUT, Titebond Moulding and Trim Glue make the fastest and easiest fillets that come out perfect with little effort and NO sanding (if you put them on right) and of course it's water-based so NO glove/allergy issues and no fumes... Stuff is plenty strong as well for most LPR/MPR builds... Later! OL JR
__________________
The X-87B Cruise Basselope-- THE Ultimate Weapon in the arsenal of Homeland Security and only $52 million per round! |
#35
|
||||
|
||||
Quote:
Yep, like the water-thin CA on balsa parts-- I do all my balsa nosecones/transitions with that treatment... but your right-- you DO have to be really careful with the fumes coming off that stuff!! DON'T EVEN THINK about doing it INDOORS-- (not unless you have a paint booth with a GOOD ventilator system!) Even doing it outdoors, do it with the wind to your SIDE-- you don't want the wind in your face (obviously) because it will blow the fumes right at you-- BUT you don't want the wind at your BACK either because the wind can 'curl around you' and whiff the fumes right up into your face anyway... Learned that the hard way... We used to use that stuff in the Police Academy to develop fingerprints-- put whatever you want to lift a fingerprint off of in a ziplock baggie and then toss a cotton ball drenched with water-thin CA into the bag and seal it up-- the fumes will bond with the oils in the fingerprint and turn them into a reddish/purply/brown crusty "image" that can be easily lifted with tape for fingerprint ID'ing... Later! OL JR
__________________
The X-87B Cruise Basselope-- THE Ultimate Weapon in the arsenal of Homeland Security and only $52 million per round! |
Thread Tools | Search this Thread |
Display Modes | |
|
|