R

rv7charlie

Well Known Member
Those who used sikaflex on their tipup (aluminum) canopy frames:

When I did my initial research on using Sika for the canopy, I remember seeing at least a couple of sites detailing the process using only the 226 cleaner, 209N primer, and 295UV.
That's what I ordered, and then later saw a post from someone who said that the 206 G+P primer was required for aluminum.

After reading the Sika documents, I found some places that say to use the 206, some places that say 'nothing may be needed', some places that talk about 'painted metal' treated differently from aluminum, etc etc.

A phone call to Sika got me a rather off-handed, 'We are going to go with the 206 option' statement, with no explanation for the seemingly conflicting instructions on the web site & in the documents.

So, what say you who have some flying hours on your glued tipups? Who glued without 206? If you didn't 206, did you paint 1st, or just use 209 on the aluminum? If you painted 1st, what did you use, & did you use 209 over the paint?

I'm sure there are many more permutations, but I'll stop there....

Thanks,

Charlie
 
What's 206? :) No, I did not paint the areas that were to be glued.. primer (209) was applied to bare metal (scuffed first, of course)
 
What you have is fine...

I cleaned with the 226 cleaner, primed my bare aluminum and the pexi with the 209N, and glued it all together with the 295UV. It's been over 2 years and in temps from -20F to 100+F. Still as strong as ever.
 
SIKA 210T used on Aluminium

Here is Australia this is what I used back in 2006. All joint surfaces were fastidiously cleaned with the recommended solvent SIKA CLEANER 1/205 prior to then priming. The recommended primers used were SIKA Primer 210T for the aluminium and SIKA Primer 209N for the Plexi.

Greg:)
 
Thanks for the replies.
Greg, I finally found the reference to the 210T; thanks.

Radomir, did you go completely 'screwless'? How about the back window? Did you use just the Sika on the front, or Van's fiberglass technique for the windscreen/metal interface?

Charlie

Here are the links to some of the various conflicting techniques.

Here's the general instructions where they say to use 209 on 'bare metal'.
http://www.sikaindustry.com/ipd-marine-window-295

It looks like the 210T is epoxy & the 206G+P is urethane.
http://www.sikaindustry.com/ipd-marine-surface-promoting

This one shows using your choice of 210T or 206G+P under 'adhesive' (295UV is described on another page as an adhesive).
http://www.sikaindustry.com/ipd-marine-surface-primerchart
 
Just to quickly answer those followup questions:

1) Screwless on the front.. no holes in the front (big) canopy part.

2) Back window -- glued to rollbar, and screws on the perimeter (aft top skin). No issues drilling back window.. it's not under load.. and doesn't get under load, so you should never see cracks there.

3) Fiberglass on the front. Would not want to glue the front end.. Fiberglass makes it easier to fair out and less worry about painting. One note though -- should have mixed some black dye into the filler (microbaloons) to make that front fillet black.. Oh well, I'll do it on my next airplane if I ever build one..
 
For another view, I riveted, not screwed, the back section except the roll-bar, which was glued. On the front section, I both glued and used screws in the sides of the canopy frame. I saw somewhere in the page on gluing an RV where someone had run screws through the plexi and inner frame but left the outer strips undrilled and simply glued them to the plexi and riveted them to the frame. This is what I did and it looks fine and seems to be perfectly strong; this way I didn't have to worry about the thickness of the Sika. I did do the front with Sika and like it; it makes a nice fillet on the inside and outside. The outside fillet was so large that I used a round plastic container top to form it. It was a little rough but I found that it sands easily with heavy grit (I used 100 grit pads). It was several months before I got around to sanding it, so it was well cured. I understand that it takes polyurethane paint to stick to it, so I will probably do a single bid layup over it just to be sure the paint sticks. One thing I have not seen people mention about Sika - be sure to get the black UV-resistant type.
 
I was not going to sand all the powder coating off my canopy bows again (steel) and glued on top of the lightly sanded powder coating. Still very much in place 6 years down the line.

The trick in sika is the primer. Especially on the plexiglass. If you don't prime, it won't stick. Period.

I used 295 UV for the glue. Can't remember my primers for the rest. I do remember using two different primers for the plexiglass and the canopy bows.

FWIW
 
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