Lifting roof XPStream - making improvements

[OP827]

It's time to continue the build. I have nine opening windows and two fixed, total of 11 windows and I am making them my own DIY style. They will be 3mm(1/8") thin tinted acrylic with light wooden frames fixed with black sealant inside the acrylic glazing. Front side windows will be opening towards inside as a modified Wiley style, while all others will be awning style, opening outside. Bigger frames were made out of pine and smaller ones made of oak. Stock for frames was cut to 1/2" x 3/4" size, painted black, cut, glued into rectangular frames. Then a 1/8" bid of sealant applied and the frames carefully positioned and pressed against the window acrylic sheets. Once the sealant is set the excess was removed with cutter and then glass pane cut to needed final size. I need to paint the moving panels and trailer body before the windows are permanently fixed. Will spray primer on doors and panels to gain some experience before tackling the roof and lower body. Weather is getting warmer here, should be good for painting soon.

[Atomic77]

Glad you're back in action! Very nice design, which I wouldn't expect any less from you Oleg. Keep the progress and the pictures coming!

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[OP827]

Glad you're back in action! Very nice design, which I wouldn't expect any less from you Oleg. Keep the progress and the pictures coming!

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Thanks very much Michael !

Today I tested the windows in the full sun and the XCELL UBS sealant I used has failed, another lesson learned and setback.

Acrylic glass gets hot in the sun and the sealant I used is not suitable, it separated at the wood, the sealant stayed at the plastic as a nice, clean strip.

Now I will have to separate frames from all 9 windows I just made and use a different sealant that is temperature resistant. Any suggestions for a sealant that will work under hot sun between acrylic and wood frame?

On the upside the windows look very nice and clean with this design, just need to find the right sealant now. OR I could make acrylic frames, which could be more work, than just use a different adhesive.... How about the adhesive that is used for replacing car windshields...It has to be temperature resistant, right?

[Atomic77]

Personally I'm a believer in 3M 5200 for just about anything you don't want to come apart. The spec sheet says to 190° F but that's for tensile strength. It will remain solid well over that.

Only thing is its white



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[OP827]

I was actually thinking 3M 5200 as well, thanks Michael. This 5200 adhesive is quite expensive here and not off the shelf, but the rework is even more expensive. I will check PDS for windshield adhesive from local auto supply for comparison and then decide. And there are some pictures of the failed test just for entertainment

I laid the windows down for testing on the hot tub and they buckled and come apart within 10-15 minutes! The adhesive cured for almost a week for all windows except three, but the new ones just came apart 5 minutes quicker than others. This adhesive is not good for this application. A the time of shopping for adhesive I did not think of high temperature during use, while I should have. Live and learn. There is also significant stress on the adhesive joint due to the window higher thermal expansion comparing to wood frame.

[Atomic77]

I was actually thinking 3M 5200 as well, thanks Michael. This 5200 adhesive is quite expensive here and not off the shelf, but the rework is even more expensive. I will check PDS for windshield adhesive from local auto supply for comparison and then decide. And there are some pictures of the failed test just for entertainment

I laid the windows down for testing on the hot tub and they buckled and come apart within 10-15 minutes! The adhesive cured for almost a week for all windows except three, but the new ones just came apart 5 minutes quicker than others. This adhesive is not good for this application. A the time of shopping for adhesive I did not think of high temperature during use, while I should have. Live and learn. There is also significant stress on the adhesive joint due to the window higher thermal expansion comparing to wood frame.

I didn't come up with this originally, maybe captain telescope? I did it the first time according to my plan. Then I did it a second time because the first plan didn't work! (Or something to that effect!) Trust me you aren't alone. There's a good reason most of the campers in the world were built in factories! Lol! On our race boats we used a windshield sealant made by Fastenal. It's the only thing we trusted on the F-16 cockpit windshield of tge race boats. In comparison, 5200 is about $26 per tube here. The Fastenal sealant was upwards of $60+. But, worth it. Basically water and heat proof. And black.

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[OP827]

Personally I'm a believer in 3M 5200 for just about anything you don't want to come apart. The spec sheet says to 190° F but that's for tensile strength. It will remain solid well over that.

Only thing is its white

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Looks like it can be black:
https://www.amazon.ca/3M-Marine-Adhesive-Sealant-06504/dp/B001R0GUZG/ref=sr_1_1?keywords=3m+5200+black&qid=1560026733&s=gateway&sr=8-1

[Atomic77]

Personally I'm a believer in 3M 5200 for just about anything you don't want to come apart. The spec sheet says to 190° F but that's for tensile strength. It will remain solid well over that.

Only thing is its white

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Looks like it can be black:
https://www.amazon.ca/3M-Marine-Adhesive-Sealant-06504/dp/B001R0GUZG/ref=sr_1_1?keywords=3m+5200+black&qid=1560026733&s=gateway&sr=8-1

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[OP827]

Agree Michael, build technology in a factory would be tested and proven by prototype before going full scale commercial. I do not want to sound like Captain Obvious, but they would not be in business, if they do not engineer and test their products. I am thinking the windshield adhesive would be more suitable, just because of the high temperature, but will compare by Product Datasheets. I am OK with failures, this trailer build is like a Test Laboratory, I am sure something else would fail or come apart. Happy building!

[Atomic77]

Agree Michael, build technology in a factory would be tested and proven by prototype before going full scale commercial. I do not want to sound like Captain Obvious, but they would not be in business, if they do not engineer and test their products. I am thinking the windshield adhesive would be more suitable, just because of the high temperature, but will compare by Product Datasheets. I am OK with failures, this trailer build is like a Test Laboratory, I am sure something else would fail or come apart. Happy building!

One of the things that Carrie and I always talked about while building our camper is, a factory would do R&D, build a prototype, iron out the bugs through multiple processes then finally come up with a completed part. In our case, we had to do all of those things in one try and get it right the first time because we couldn't afford to make mistakes! There's the challenge of it!

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[OP827]

3M 5200 product datasheet says about limitations:
"- 3M™ Marine Adhesive/Sealant Fast Cure 5200 is not recommended for the
installation of glass, polycarbonate or acrylic windows that are not also
mechanically fastened with a system designed by the manufacturer. Inconsistent
adhesion of these unprimed substrates, specific design of the window, and
movement due to thermal expansion and flexing, may cause application failure."

I feel that any polymer glue can fail at acrylic and wood joint under the heat that these windows are exposed to, except high temp silicone, but then silicone may still be too weak to withstand the shear stress caused by thermal expansion difference between wood frame and acrylic /plexiglass. I made a sample with acrylic frame piece and glued it with acrylic cement which is essentially an acrylic welding with a special solvent. Will report how that went after a few days.

[S. Heisley]

If you have to remove or replace a window, be aware that 3M 5200 is pretty much permanent; so, removal of something attached to wood will tear the heck out of that wood, even painted wood. (Been there, done that.) 3M 4200 is a little bit easier on the wood frame and will still hold well, IMO. It seems that maybe windshield adhesive might work, though. If you can, try using some on some scraps and see how it does and what happens when you try to tear them apart.

[twisted lines]

When good enough; just isn't

Crazy Mind and Matter

[OP827]

If you have to remove or replace a window, be aware that 3M 5200 is pretty much permanent; so, removal of something attached to wood will tear the heck out of that wood, even painted wood. (Been there, done that.) 3M 4200 is a little bit easier on the wood frame and will still hold well, IMO. It seems that maybe windshield adhesive might work, though. If you can, try using some on some scraps and see how it does and what happens when you try to tear them apart.

Thanks for input. I am realising that the design with wooden frame glued to acrylic without mechanical fasteners may not work. Reason for that is a big difference in thermal expansion between wood and acrylic. I saw how acrylic was expanding in the direct sun and forming a sphere on the wood frame until the glue joint got hot and gave up. Tinted acrylic is getting very hot in the sun and I think most of the glues, including windshield polyurethane can fail. Windshield adhesive max temperature is 90C(194F), but the problem is the stress to the joint is the greatest when it is hot and therefore most likely with time it will fail. I assembled a small window today using acrylic cement with acrylic frame(not wood). This time I will test it out in the sun when weather improves here before I make the decision to produce the rest of windows. There is rain in the forecast, so I may work on something else, instead of windows then.



I added a second pane of acrylic, just to experiment how it will work. Second pane is a clear acrylic sheet fixed with stick-on Velcro so it can be removed if needed to clean dust or condensate inside the assembly. I am thinking of testing stick-on magnetic strip too. The window is a quite lighter tint than appears in the photo.

Cheers

[OP827]

Another update at the end of the weekend. I only spent a couple hours this weekend, small progress, but still a progress. The new construction of window apparently working much better than previous one. There appears to be no significant stress with same material acrylic frame under sun heat, no distortions like it was with wooden frames. Try fitted the small window on the wall. I can now continue with making the windows this way. Made all windows and door drip edges out of 1/4"(6mm) Baltic(Russian) birch plywood. I will coat it with epoxy and fibreglass cloth once installed in place, same way as I did with the roof drip edge. Here are some pictures from today:



Happy building