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Window Installation

jeffwhip

Well Known Member
I recently went down to Glo Aircraft Painting in DFW and was talking to Mark about my future paint job. He asked me several questions about my upcoming window installation and brought up something I hadn't thought of.

He told me that he has seen several people bring planes in to be painted where the windows had been glued in and instead of fiberglassing over the outside, the people had elected to use proseal.

Mark said the individuals had taped off the window and the finished product looked like a rubber seal. Has anyone here done that? What are your thoughts about gluing the windows in with Lord Adhesive and then using proseal? This would seem like it would eliminate the possibility of the paint cracking. What is everyone's thoughts?
 
If I was doing it again, I'd get the black Lord Adhesive with the (relatively) short cure time and glue the aft and door windows with that. Those windows are small enough I'm pretty sure I could get the windows in before the adhesive set. I'd fill the gap around the windows with proseal and be done.

Depending on how the small windows went, I'd consider doing the windscreen the same way. However, the short working time of the black adhesive would come into play in that decision. It would be an expensive mistake if you couldn't get the windscreen set in time.

I haven't seen anyone put a wide band of proseal over and around the windows, which is what you're contemplating. It might work, and at worst, you could scrape/sand it off if you didn't like the first one, then come up with an alternative.
 
Black Lord Adhesive

I'm not sure you'd have the time even with the small windows. The working time with the black lord adhesive is no more than 10 minutes...
 
I did SilPruf, following a very professional tutorial on YouTube.

No regerts ;)







My paint may go on to do lots of things, but cracking around the windows is not one of them.
 
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I'm not sure you'd have the time even with the small windows. The working time with the black lord adhesive is no more than 10 minutes...

You don't think so? I'd estimate that 5 minutes is very doable with the small windows. Run a bead of adhesive - 1 minute. Place the window - 1 minute. Press and cleco into place - 3 minutes.
 
You don't think so? I'd estimate that 5 minutes is very doable with the small windows. Run a bead of adhesive - 1 minute. Place the window - 1 minute. Press and cleco into place - 3 minutes.

10 minutes seems very doable. Just a limited margin for mistakes.

Larry
 
well...

Maybe I used a bit too large of a bead of lord adhesive but I did not want any voids. So, it squished out and I wanted to make sure of a nice clean fillet inside and out.

I had sufficient time with the white lord adhesive to easily accomplish this on the rear windows. The doors worked out fine but just barely as the adhesive was nearly unworkable at the end.

The windshield I had the same issue due to excess adhesive squeezing out in front of the cabin top brace...difficult to clean up without making a mess.

Overall it turned out fine, nice fillets on the inside and outside and more importantly, no voids...

It would definitely suck if the adhesive hardened before you were done...
 
I used Sikaflex but the same process as the SilPruf method requiring no fiberglass work. I'm extremely pleased with the result thus far. I haven't painted yet, but the install and finished bead that will go on after paint results in a very nice look in my opinion. The install was rediculously easy as well.
 
I used Sikaflex but the same process as the SilPruf method requiring no fiberglass work. I'm extremely pleased with the result thus far. I haven't painted yet, but the install and finished bead that will go on after paint results in a very nice look in my opinion. The install was rediculously easy as well.

I don't think I've heard of Sikaflex. I'll have to research that and see if that's better than Lord Adhesive.
 
Sika is used all the time by the two seater crowd .. I did my main canopy and rear window with the stuff with great results. No screws!

Sikaflex 295 UV is what is typically used for a plexi to metal bond. Lots of posts here on VAF.

It's a lot less messy than pro seal.
 
I used Sikaflex but the same process as the SilPruf method requiring no fiberglass work. I'm extremely pleased with the result thus far. I haven't painted yet, but the install and finished bead that will go on after paint results in a very nice look in my opinion. The install was rediculously easy as well.

Hey Tim. Do you have a recommended source outlining the process you used?
 
Randy, I used the exact same method as the SilPruf that's documented on the YouTube series, except I used Sikaflex instead of the SilPruf. The Sikaflex is not silicone based and therefor (in theory, according to the MFR) can be painted over if desired. I mainly used it because it's UV and you can get it in black. I also wasn't as paranoid about cleanup since even residue of it won't affect future painting.

The primer for it is a bit expensive, but still not terrible compared to the cost of the build.

I'm just not great at fiberglass work and I did not want any chance of paint cracking down the road.
 
Thanks Tim. I just started watching this series yesterday. It is quite good so far. I?ll have to look into the benefits of Sikaflex as well.
 
Google search Glasair Sportsman window installation. You should come up with a five part instructional series someone did. Walks you through the process. Except for the windscreen the Sportsman has the same window joggle. With a little modification, it can also be utilized for the windscreen. I used Silprof. Others have used Sika. You end up with the same results. Silprof is silicon so it’s 100 percent UV and waterproof. You need to be carful not to get it on anything to be painted in the future or your paint may fish eye. Sika is not 100 percent UV proof and could break down over time, but the way we take care of our planes once built, probably will not make any difference. Watching the video is the best to do.
 
I am planning to do silpruf on mine so I hope you have a good experience with the final product. It'll be some time before I get that far in the build, so I expect to hear good news from you by then!

I did SilPruf, following a very professional tutorial on YouTube.

No regerts ;)

Now I need a candy bar.
 
I used Sika on my -9A tip up. Lots of research and anxiety, but in the end it was a breeze. Couple of things to note - 1. I?m not flying yet, so... and 2. this stuff is messy. In my mind every bit as messy as pro seal. I didn?t tape off enough area and made quite a mess.

Working time with Sikaflex was not an issue, and glad to have avoided drilling the canopy.

Lars
 
I used Sikaflex but the same process as the SilPruf method requiring no fiberglass work. I'm extremely pleased with the result thus far. I haven't painted yet, but the install and finished bead that will go on after paint results in a very nice look in my opinion. The install was rediculously easy as well.

Tim,
What color of sikaflex did you use? Is there a certain type that?s a higher quality?Thanks for all the feedback everyone!
 
Tim,
What color of sikaflex did you use? Is there a certain type that’s a higher quality?Thanks for all the feedback everyone!

I am doing sika as well. Plan to do it next week, as I decided to leave the windows out as I wrap up my wiring this week. Windows are all cut and prepped. Way easier getting in and out of the seat 200 times without the windshield:) The 295 UV is what you want. Only available in black. You need a specific activator and primer, but I don't have them handy, but will post tomorrow unless Tim beats me to it.

Larry
 
Randy, I used the exact same method as the SilPruf that's documented on the YouTube series, except I used Sikaflex instead of the SilPruf. The Sikaflex is not silicone based and therefor (in theory, according to the MFR) can be painted over if desired. I mainly used it because it's UV and you can get it in black. I also wasn't as paranoid about cleanup since even residue of it won't affect future painting.

The primer for it is a bit expensive, but still not terrible compared to the cost of the build.

I'm just not great at fiberglass work and I did not want any chance of paint cracking down the road.

I like this idea. Definitely more a fan of black window sealant than the grey-silver silpruf.
 
I used Sika on my -9A tip up. Lots of research and anxiety, but in the end it was a breeze. Couple of things to note - 1. I?m not flying yet, so... and 2. this stuff is messy. In my mind every bit as messy as pro seal. I didn?t tape off enough area and made quite a mess.

Working time with Sikaflex was not an issue, and glad to have avoided drilling the canopy.

Lars

I also used Sika on my -8 and it has been flying for 12 years > 750 hours with no problems. However... when I looked at using it on the -10 windows, I could not reconcile the recommended joint thickness with the window joggle. Sika recommends a much thicker bed of adhesive and that would have raised the window quite proud of the frame. I ended up using Lord adhesive on the front back windows, I have not yet done the front canopy, I may use Sike there as there is much more room for thicker bed of adhesive.

Steve
 
The adhesive you'll want is the 295UV which is black. The activator (which acts as a cleaner/degreaser) is Sika 205. The primer (which is black and is painted on before applying the Sika 295) is 206GP.

I bought all of it from Merritt Marine Supply for about $125 with shipping. I ordered two tubes of the 295UV which was more than enough for the four windows but I'll probably need one more tube for the windscreen.
 
Steve, I had a few areas that were thinner than the recommendation, but most spots were more than enough per the instructions for proper bonding. I'm not overly concerned based on tests that I saw from others using scrap material just to test the bonding ability. The nice thing about the windows on the 10 is the size of the joggle which will still yield at least .5-.75" wide surface for the window to bond to.
 
Please see this thread

Code:
http://www.vansairforce.com/community/showthread.php?t=166973&highlight=sika
 
As a Glasair Sportsman builder, I'll chime in here.

Silpruf is indeed a silicone-like material, rubbery, flexible. In thin layers it has no adhesive bond strength at all, you can just rub it off with your fingers. Get some thickness and its characteristics seem to change exponentially. I glued together two pieces of .032 6061 aluminum with a 1/8" thick x 3/4" wide bead of Silpruf. Ended up destroying the aluminum trying to get the pieces apart.

Silpruf is fairly "runny" and has a long cure time. If you want to do a neat job, that long cure time is critical. Cleaning up, faying out, smoothing etc takes some time. The windows in our Sportsman look like they were installed in the Gulfstream factory rather than a homebuilder's hangar.

The video series referenced previously was put together by "some guy" named Zach Chase of Fibertech Composites. He is a composites guru and he pioneered this method of taping, masking, color-saturating the inside of the windows, etc. I received instruction from him directly, long before those videos were posted to Youtube. His method is pretty much foolproof if you follow it. Cut corners and your results may not be what you were hoping for.

If using Zach's technique, I will caution about the color of the sealant used. From an aesthetics perspective, we want our eyes to be drawn to the gorgeous, sexy, flowing lines of our aircraft. Use of a dark color of window sealant produces the opposite effect by starkly outlining and highlighting the windows. We then focus on the windows rather than the flowing lines of the aircraft. Our eyes tend to get drawn to those things that stand out the most (gee, ever try using BOLD text to get attention? - that's because our eyes are drawn to things that stand out!). Same deal for dark window sealant. I should likely mention that Craig from SchemeDesigners also cautions against dark outlines for windows, doors or other features. Since he's a pro in the business I tend to follow his advice.

In the Glasair aircraft, the "aluminum" color of Silpruf seems to be the go-to color and in fact is what we used on our Sportsman. Unless one has a very dark paint scheme in mind, the use of a very dark window adhesive will likely produce a less-than-pleasing visual effect.

I should also mention that Silpruf has a "best before" date which must be respected. If ordering on line, ensure the vendor provides you the "best before" date before finalizing the transaction. The stuff typically is in the $8-$14/tube price range. For an RV10 you will likely need 4 tubes. Buy 6 to be sure. Yeah, sometimes we do dumb things like leaving the caulking gun pointed nose down while a pile of material builds up on the floor under it. Nah, that would never happen to me. Never!
 
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..ar.

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If using Zach's technique, I will caution about the color of the sealant used. From an aesthetics perspective, we want our eyes to be drawn to the gorgeous, sexy, flowing lines of our aircraft. Use of a dark color of window sealant produces the opposite effect by starkly outlining and highlighting the windows. We then focus on the windows rather than the flowing lines of the aircraft. Our eyes tend to get drawn to those things that stand out the most (gee, ever try using BOLD text to get attention? - that's because our eyes are drawn to things that stand out!). Same deal for dark window sealant. I should likely mention that Craig from SchemeDesigners also cautions against dark outlines for windows, doors or other features. Since he's a pro in the business I tend to follow his advice.

.

Unless you go for the "Black Outline" method shown on some examples here...:)
 
clean up silpruf

...Silprof is silicon so it?s 100 percent UV and waterproof. You need to be carful not to get it on anything to be painted in the future or your paint may fish eye....

I went the route of Silpruf as well but I did it long ago and did not have the benefit of the videos to warn me about "not getting it on anything" thus my window edges were not taped off and there is a bit of ooze that you can see around them.

What is the best way to clean this up to prevent paint issue? Obviously I have not yet painted.
 
One of the biggest no-no's I'm told is to make the mistake of sanding off the silicone residue. That seems to drive the silicone down into the tiny fissures made by the sandpaper.

I've had success with using a clean paper shop towel soaked with acetone to clean off the residue after first having used a fresh razor blade to cut the residue down to the bare minimum.
 
The adhesive you'll want is the 295UV which is black. The activator (which acts as a cleaner/degreaser) is Sika 205. The primer (which is black and is painted on before applying the Sika 295) is 206GP.

I bought all of it from Merritt Marine Supply for about $125 with shipping. I ordered two tubes of the 295UV which was more than enough for the four windows but I'll probably need one more tube for the windscreen.

Tim,
Thanks for the info! I just placed my order.
 
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