Working with Lexan

[tlsmit1]

The front window of my '62 Tradewind leaks like a sieve. (Shocking, I know.)

I've removed the window and replaced the gasket. The glazing strips were all gunked in with some previous silicone hack job, and so I was also planning to re-seat the glass in its frame. Anyway, I broke the glass while attempting to chisel it out. This was probably for the best, as it seemed to be un-tempered plate glass. One flying pebble on the highway, and wham-o.

Since it's the front window, I figure I'll throw authenticity under the bus and replace it with Lexan. I can buy it from my Home Depot, but I've never worked with it before. Do I score it and crack it, like I do with the cheap plastic sheets that they sell? Or do I cut it with a table saw?

Thanks!

[bsshrink]

I cut my front (side) window from Lexan with a Skil jigsaw set at low speed. The 1969 Airstream was the first triptych front window pattern & the side windows were bowed to fit the front section curve, so I had to curve & cram to get it in the channel.
Best advice: buy as many sheets of Lexan as they have & take the unused ones back later. I broke 5 under the curving stress B4 one popped into place. Probably not as important with the '62. Lexan is much thinner than Corning glass so be prepared to fill the channel with something.

[Joe Palmieri]

Lexan can be worked with woodworking tools. Don't let the cutting tools heat up as the Lexan will soften and become gummy. A little heat from a heat gun will help you form the bend.

[dwightdi]

Because it is much more ductile, you need to cut it, as it will not crack. It is sensitive to solvents so do not use any on it. It also yellows and loses some transmittance with time. I have had one large Lexan window for 22 years in my 63, Many thicknesses are available, as well as tints. Plain double thickness window glass works well for smaller windows in early 60's Airstreams. I have broken two of them in 22 years. No big deal. I would go with glass for the front window and install a rock guard.

[Protagonist]

Originally Posted by dwightdi

I would go with glass for the front window and install a rock guard.

If you go with a glass front window, don't get tempered glass. Get laminated glass.

Tempered glass is what they use for automotive side windows, and it shatters into a bajillion tiny pieces when broken. Laminated glass is what they use for automotive windshields. If it's hit, there's a good chance it will just chip or crack instead of breaking (and can often be repaired in place by companies like Safelite Auto Glass). And if it does happen to break, the plastic laminated into the glass will hold everything together instead of leaving you with a great gaping hole where your window used to be.

[tlsmit1]

Originally Posted by Joe Palmieri

A little heat from a heat gun will help you form the bend.

No bend, fortunately. The front window of my 62 is just a 20 x 41 inch rectangle.

It seemed to have been filled with standard, untempered plate glass which is likely why it broke so easily when I tried to mess with it.

At some point I might get a piece of laminated glass for the window. At the moment, though, I want / need to get the trailer back into towable condition pretty quickly, which is why I'm going with Lexan.

(On Friday I have to tow it about 20 miles to a state police barracks. Once they inspect it, I can finally trade its salvage title for a real title and--whee!--get a license plate and go camping!)

[Morgan guy]

When I cut lexan or other plastics, I reverse my saw blade. That helps eliminate chipping. You have to cut slowly because you are sort of melting the edge of the plastic as you cut it.

[mimiandrews]

If you have a table saw (or access to one), Lexan can be cut fairly easily using a plywood blade (lots of small teeth), slow blade speed, and slow feed rate. The trick is to keep the saw teeth from snagging and to keep the temperature rise from friction to a minimum.

[perryg114]

You can cool your saw with water but not solvents. I have seen edges of Lexan crack after cutting if it gets too hot. Fine teeth and slow and cool with water if you can.

Perry

[Lumatic]

I use use a jigsaw with a fine tooth blade.

Being pretty flexible a front window will bend with wind pressure. Do you have a rock guard?

You can get UV resistant Lexan to cut down on yellowing.

Glass is also more scratch resistant.

[tlsmit1]

My only hesitation with a rock guard is visibility. Right now, when towing, I can see straight through the trailer and get a pretty good look at traffic behind me. I'd like to keep that ability if I can.

[mandolindave]

A person working the gate at a festival, placed a sticker on my sunglasses. I used water to get the sticker off. I was afraid to use anything to remove the adhesive. Is alcohol a no no? ( no...not to drink, to get the goo off) Sorry for hijacking

[Foiled Again]

Lexan and all polycarbonates really really hate ammonia! It creates that surface haze you see on old headlights. Keep the Windex away from your Lexan windows.

Most stickers will come off of most surfaces with plain old vegetable oil, WD-40 or "friction picking" (put duct tape over sticker, rub to warm for 30 seconds, pull from one edge, and encourage the sticker to surrender by using a fingernail on the edge of the sticker. Some stickers come apart leaving only a tiny layer of paper and the adhesive. A second application of duct tape will generally get this layer off.)

I'm not sure about the solvents that Lexan can't tolerate, but I'd lay odds that Lacquer Thinner is one. Finger nail polish remover would definitely do a number on it. Plain old rubbing alcohol might be OK, but I'd rinse thoroughly afterwards.


BTW - The big box stores charge way way too much for all kinds of plastic sheeting. Find a place that makes store fixtures, high end bath fixtures, etc. They'll often sell you "scrap" sheets that are leftovers for really reasonable prices.

Paula

[tlsmit1]

Originally Posted by Foiled Again

BTW - The big box stores charge way way too much for all kinds of plastic sheeting. Find a place that makes store fixtures, high end bath fixtures, etc. They'll often sell you "scrap" sheets that are leftovers for really reasonable prices.

That's a useful idea; thanks.

[Protagonist]

Originally Posted by Lumatic

Glass is also more scratch resistant.

That's the problem with Lexan; you can hit it with a hammer without breaking it, but you can scratch it with a dry paper towel.

[Joe Palmieri]

Originally Posted by tlsmit1

My only hesitation with a rock guard is visibility. Right now, when towing, I can see straight through the trailer and get a pretty good look at traffic behind me. I'd like to keep that ability if I can.

Your rock guard can be made of clear Lexan. I use Novis #1 to clean and polish the Lexan windshield on my boat. It works best with a soft cloth. I am happy with the results.

[perryg114]

Lexan is alot more prone to cracking than most people think. Alcohol is not good for it. The ammonia based cleaners probably have a little alcohol in them. Vinegar is probably safe. Sometimes cutting it or drilling holes in it will make it crack. Especially if it has been sitting around for a while. We make bullets out of it where I work and we have problems with it cracking.

Perry

[Lumatic]

Originally Posted by Joe Palmieri

Your rock guard can be made of clear Lexan. I use Novis #1 to clean and polish the Lexan windshield on my boat. It works best with a soft cloth. I am happy with the results.

IMHO a Lexan rock guard to protect a Lexan window is like wearing a belt and suspenders.

[tlsmit1]

Originally Posted by Lumatic

IMHO a Lexan rock guard to protect a Lexan window is like wearing a belt and suspenders.

I think that the suggestion was meant to be a Lexan rock guard for a glass window, which would preserve my ability to see through the trailer while towing.

[dwightdi]

I have seen people use a flat tinted Lexan for the stone guard on the front window. It gives nice shade when tilted up and still allows a little see through.