On the top (smaller) I tried microballoons and epoxy. I even used a special type of microballoons to make the job easier. The mix was applied with a fine sponge so I could press in the mix into the pin holes.
After curing I sanded and sanded and sanded I abandon any further use of epoxy for fill.) The top was completed with Superfill and Rage and block sanded.
On the bottom, I used Superfill. I brushed it on but you could roll it as well. I found the roller would "pull" the primer back out after you rolled. I "finger painted" Superfill into any obvious areas. Superfill sands like butter and I did the lower in a fraction of the time.
After I thought it was good, I sprayed a heavy coat of Superfill onto both pieces. A few more imperfections were noted and filled. The entire cowl was block sanded wet with 320 wet and dry and most all of the primer was removed.
DanH;187257 You can't fill pinholes with microballoons. Dry micro [I said:adds[/I] pinholes due to air entrained during mixing. Even if you don't entrain air, every balloon is a hollow sphere to sand open.
Ahhh, always nice to be remembered
snip....
Now, the community seems to be like just about every other one out there -- people throwing bombs over the fence, etc....snip
The personal snipping stops now. I have no tolerance for this stuff and will ban the next account that does it for a month. Think I'm kidding?
Now, please return to helful, civil discourse (please).
b,
dr
Doug, with due respect (and I mean that), I disagree entirely with Bob Collins. I think that Vans Airforce can afford a bit of thrust and parry. We're all grown up men and the world is basically competitive. It is therefore not unreasonable for Vans Airforce to reflect that fact.
In reality I sense that VansAirforce has become so progressively censored that it is threatening to become an entirely filtered affair...a bit puerile actually. Even posts that are just mildly cynical are being removed by overzealous moderators.
I don't think that any post on this particular thread has grossly overstepped the mark at all. Totally censoring Dan Horton's post was uncalled for. He made a very valid technical point in that post about the dangers of mix and matching different manufacturers products. You threw out the baby with the bath water.
Don't go too antiseptic Doug. A lot of the people who are frequent contributors of real and meaningful data and knowledge to this forum are by their nature very opinionated...it comes with the territory. Vans Airforce will be all the poorer if they are driven away. It worries me somewhat when I see contributors of the calibre of Dan Horton and George Jetpilot being censored over what could only be considered as very minor lapses of decorum.
Personally I'm quite prepared to put up with the occasional argy bargy as long as it's accompanied by interesting information and/or intelligent discourse. Goodness, sometimes it's actually quite entertaining.
Gang,
What is the best way to fill the weave on the fiberglass cowl? The imperfections I'm seeing are MUCH larger than just pin holes. They are about 1/4 to 1/2 the thickness of the fiberglass cloth because it is that cloth that is sticking up.
Thanks!
.....
You are right, Greg. You can use epoxy on polyester but not the other way
around.
.....
I had good results doing as vans reccomended by thinning west systems with acetone about 50/50 and brushing on, then sanding between coats, about three coats worked for me. Lighten up troops, enjoy the sharing of information even if you don't agree, this is supposed to be fun.
When others are talking about using raw epoxy to fill pinholes are they using it thinned or unthinned. If they are thinning, what are they using and in what percentage....and does the process have manufacturer's recommendation.
Alex B said:Bill,
After Cory Bird took grand champ at OSH a few years back, he revealed his secret technique to fill pin holes. It's fast, easy, cheap and light weight. Here's an explanation from the Cozy forum:
06-13-2005, 11:06 AM
Wayne Hicks
Member Join Date: Aug 2002
Posts: 511
Cory Bird's Raw Epoxy Finishing Technique
________________________________________
I recently read about the finishing technique that Cory Bird used on his OSH grand champion Symmetry. The technique is dry micro, contour to 36 grit (yes, 36 grit), then skim coat and squeegee up to 5 successive coats of pure epoxy (yes, pure epoxy) to fill all pin holes and scratches. Curious, I tried a variant of it this weekend on the bottom of my wing. 4 pinholes TOTAL! Except for two small low spots near the aileron spars, I was almost ready for paint on the very first try. I am so psyched I can hardly stand it. If I was starting from scratch I would definitely give the full technique a try!
I was already contoured to 120 grit on my wings when I came across the article, so I didn?t use that many coats. In my "test case", I applied the pure WEST with a roller, waited 10 minutes, the squeegeed it all off. The pinholes were almost filled. So I applied another layer, this time lightly squeegeeing to leave a very thin layer. I probably left on too much WEST. I need to find the balance between scraping it all off and leaving barely enough on.
Anyway, I started sanding off the WEST. True, it was a little hard to sand off. But a MIRACULOUS thing occurred. Almost all the pinholes and large scratches got filled. And I'm talking about very big pinholes, like the size of small peas. Even more miraculous, because the WEST is so tough, my 3-foot sanding board (100 grit, then 120 grit) "cut" the tops off the most inconspicuous of high spots that my first contour to 120 never caught! I continued to sand, sand, sand until all the WEST was almost, almost, almost sanded away.
Steve (an exceptional hangar mate if ever there was one) sprayed the wing with primer. Like I said above, I sanded it off and was rewarded with a wing bottom that had only 4 pinholes TOTAL. For test comparison, I didn't WEST the lower winglet. Just sprayed primer over it. Of course, it was loaded with pin holes.
So what does this all mean? Since this is the first time I've ever filled, sanded, and primered ANYTHING, I have no basis for comparison. But I can vouch that skimming with WEST really does fill scratches and pinholes of all sizes. And if you're an aggressive sander like me (meaning, I have no patience, no finesse!), the hard coat left by the WEST helped me to achieve an even better contoured finish. The other obvious benefit is leaving the tiniest of WEST layer helps to harden the micro. I've heard others say that this helps prevent print-through later on in life.
__________________
Wayne Hicks
Cozy IV Plans #678
http://www.canardzone.com/forum/showthread.php?t=1322
Here's a longer post with pictures:
http://www.rvplane.com/pdf/SkimCoating.pdf
This was technique was offered in the RV forum but I don't think the metal people believed it would work. (Yes, I saw your post. )
http://www.vansairforce.com/community/showthread.php?t=25421
I'll be glad to help you.
Alex
With the pin holes filled in the top cowl it is time to move to the bottom. I noticed that the fiberglass weave really shows through on the bottom cowl.
What is the best way to fill these very deep and visible imperfections?