What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Canopy installation

warbingtonmasonry

Active Member
Dear group:
As an atheist I make no apology to the faithful for piloting a single-seat Zenith CH150 Acro, whose side-tilting single-place canopy was destroyed (by me)in the wind by inadvertent failure to latch after closure.

Airplane Plastics in Ohio built a new canopy to my frame and specifications in record time at extremely reasonable cost. I believe the canopy they made fits my frame perfecly. Included by Airplane Plastics were several hours of advice and instruction and opportunities to see their shop in action fabricating canopies. A picture is worth many words, and so was the chance to actually see skilled men shaping canopies. I am a very satisfied customer, and reccomend Airplane Plastics in Ohio highly.

My airplane has a canopy frame made, it appears, of round thin wall 3/4" steel tube (steel electical conduit?). It has a good latch/lock mechanism and alignment pins.
The canopy was screwed to the tube @ 4" centers. The #10 screws held, under finishing washers, an aluminum skirt. It had held up well, until I forgot to latch it.
My question is whether the adhesives used in canopy installations will attach satisfactorily a canopy to a steel tube frame. The tube can be stipped of paint and cleaned. The canopy is tangent to the tube at one point along the perimeter of the frame. The canopy can be shimmed out to accomodate any reasonable thickness of adhesive, and the adhesive could be filleted easily at least as wide as the diameter of the tube frame. Alternatively, a 1"strip of sheet steel could be welded to the exterior of the perimeter of the frame to provide adhesive surface. Such welding would be a big job. The gluing surface would probably be optimal, as the plane of the sheet would be parallel to the canopy.
I am reluctant to drill screw attach holes if there is a better way to attach the canopy to the frame.

The canopy is not yet trimmed.
Any and all ideas or advice are most welcome.

Thanks
 
Search the forums for "sika" or "sikaflex". You'll find a treasure trove of information, links with photos, etc.

Short answer: many of us have used this product to attach plastic canopies to steel frames made of even smaller diameter tubing than you reference. It works great.
 
I used 3M 5200 fast cure on my canopy. No mechanical fasteners, remains flexible, single stage, recommended by Todd at Todd?s Canopies. 3 years, 190 knots peak speed, no cracks and no problems. I have a piece(5? Long) in my hangar with a standing bet- put one end in the vise, and with a pair of channel lock pliers, if you can get it apart $100 is yours. One cartridge will do it for about $25.
 
Thanks for the tip.
One cartridge to do one canopy?
Should the canopy be shimmed away from the frame to allow for some non-zero thickness adhesive joint? It seems 1/8" minimum joint thickness is what I am hearing.
Can it be applied with a common caulking gun?
Sounds like either it or the Sikaflex products would be a good choice.
 
I used some thin aluminum washers as a spacer, and Clecos to hold canopy to rail until adhesive was cured. A regular caulking gun is all you need to apply it, and sandpaper to scuff surfaces, and Naptha to clean prior to applying adhesive. I did not use a full cartridge of adhesive on my -4.
 
I used some thin aluminum washers as a spacer, and Clecos to hold canopy to rail until adhesive was cured. A regular caulking gun is all you need to apply it, and sandpaper to scuff surfaces, and Naptha to clean prior to applying adhesive. I did not use a full cartridge of adhesive on my -4.

So you drilled through canopy and frame (clecos and washers to hold) and just skipped the rivets/screws?
 
Thanks, Kurt.
That is exactly what I need to know. No screws/bolts through glass to tube?

That's correct. Only one hole in the canopy for the latch mechanism to go through. There's no way around that one on a RV side-by-side slider canopy. No other fasteners nor holes in the plastic canopy.
 
I am reluctant to drill holes in my new canopy,
and am 99% persuaded to only glue it on with 3m 5200.
I looked at an RV4 with a side-hinged canopy.
Screws every 4-5" only is what fastened it to the 1/2" tube frame.
 
I used 3M 5200 fast cure on my canopy. No mechanical fasteners, remains flexible, single stage, recommended by Todd at Todd?s Canopies. 3 years, 190 knots peak speed, no cracks and no problems. I have a piece(5? Long) in my hangar with a standing bet- put one end in the vise, and with a pair of channel lock pliers, if you can get it apart $100 is yours. One cartridge will do it for about $25.

Hi Mike!

I'm close to having to make the decision whether to use fasteners or adhesive.

How many years and hours on the RV-4 now?
Any signs of cracks, grazing or other adverse effects on the canopy?

How thick were the washers (spacers)?

I saw one post where no spacers were used -- not needed per 3M. I find that unlikely due the the expansion differential, about 1/4" over 160F (-10F to 150F).

The 3M 5200 seems a lot cheaper than Sikaflex and appears easier to apply?

Finn
 
I have had to remove a canopy skirt on my -4 build due to excessive gap when the canopy is closed. I need to make it 1/6th wider. So I drilled out all the rivets and pulled it off. It was stuck with 3m 5200. That stuff sticks like $!!# to a blanket. I need to try to remove it. Tried a heat gun. Nothing. Razor blade doesn't really work - you have to put tons of force on and that is a really good way to slice open the personal plumbing. Anyone have any ideas on how to remove it?

If I had any doubts about this stuff for keeping my canopy on they are gone. I understand it is not UV resistant so it needs to be painted. but the stuff is stupid strong. No primers or fancy prep - just cleaned and degreased with rubbing alcohol. I am not using fasteners.
 
Last edited:
Back
Top