Putting Plexi in for Vista Windows - GMC 4108.

[Chaz]

OK, so, anyone ever replace their vista windows with plexiglass?
My windows were gone in my Buffalo when I bought it, and they had 1/4'' formed fiberglass panels in there, instead.
I am trying to sneak up on this project so I only had 1 window cut out of 1/4'' plexi to see if it would work.
I eased the edges a bit and tried to get it in with soap water, window tools, etc.........no luck. It has strong "memory" and wants to go back to flat. I think I am either going to have to form the "curve" into the plexi - I hope a heat gun and some pushing will work - or, maybe, go with 3/16'' plexiglass.
Any of you had this experience and have the tricks or tips on how to do this?
Any insight is MUCH appreciated!!!!!!
Chaz

[richard5933]

Plexiglass can be formed around a mold pretty easily, at least in my experience bending sheets of it into boxes.

Can you set up a mold of some type which is laid horizontally? Then lay the plexiglass over it and heat it up just enough that it slumps over the mold and into shape. Might practice with some scrap first.

[Chaz]

Well, I got them in. Interesting process and not really a job for one man alone. I did "dry fit" the pass. side, by myself first, to make sure they fit but, it was a bear. Two guys are way better.
So, here is how it went down in case you, or, someone else is interested.
I used Trim Loc 2 piece perimeter gasket - 1/8'' and 1/4'' grooves - and it worked surprisingly well. dtcerrato (Dan) was VERY helpful is coming up with the center gasket, which I could not find. A HUGE thank you to Dan!!!!
So, I had 2 - 1/4'' plexi-glass windows cut to the exact size of the fiberglass panels that were in there. I "eased" the edges so the tools would slide better when putting them in. I didn't really radius the edge, just ease it a bit.
I tried a couple different ways to heat and bend the plexi but, I gotta tell ya, 1/4'' plexi will fight the hell outta ya. I can also tell ya, I found a small tip that works the same with sheet metal - if you use a heat gun, or heat source like it, the plexi when heated will move towards the heat source so (molecules expanding, etc.), so heat on the side of the "outside" of the radius. It helps a bit as it slightly comes toward the heat.
I have a welding fab shop so I clamped 2 pieces of angle iron on the bench far enough apart that when I bent the plexi to fit inbetween them, I had about a 10'' "bow" in the glass from the bench to the plexi. That works way better than doing it by hand!! I then started heating the plexi a the the outside end first, where there is more curve. It took a long time as I am not familiar with how much or how hot it needs to be but, I did also use a temp gun and found that somewhere around 250*, or so, seems like about where it needs to be. I did have a small spot of distortion on the first window where I heated it a bit too much.
My buddy Rusty helped me install them. I used 3M urathane sealant to seal the gasket to the flange of the bus. Tip - If you cut off just a small amount of the tip of the sealant, you can stick it into the 1/8'' groove of the gasket and put a small bead in there for when you slide it onto the flange and it will keep the mess to a minimum, and this is some good sticking stuff that is a bit tough to get off!! (don't ask me how I know )
You need the correct tools to install the window and bead. They are cheap from Amazon.
We found it easiest to start at opposite ends (Catty-corner) of each other. YMMV here but that worked for us. Be sure to use soap water as well.
Well, that is as "Cliffs Notes" of a version as I can make my explanation. I'm no great literary figure so I hope you all understand this. I would attach a couple basic pix if I saw how but, I don't. I'll do another post for them so I don't screw this up and spend another 1/2 hour typing with one finger.
Later guys.........

[dtcerrato]

Well, I got them in. Interesting process and not really a job for one man alone. I did "dry fit" the pass. side, by myself first, to make sure they fit but, it was a bear. Two guys are way better.
So, here is how it went down in case you, or, someone else is interested.
I used Trim Loc 2 piece perimeter gasket - 1/8'' and 1/4'' grooves - and it worked surprisingly well. dtcerrato (Dan) was VERY helpful is coming up with the center gasket, which I could not find. A HUGE thank you to Dan!!!!
So, I had 2 - 1/4'' plexi-glass windows cut to the exact size of the fiberglass panels that were in there. I "eased" the edges so the tools would slide better when putting them in. I didn't really radius the edge, just ease it a bit.
I tried a couple different ways to heat and bend the plexi but, I gotta tell ya, 1/4'' plexi will fight the hell outta ya. I can also tell ya, I found a small tip that works the same with sheet metal - if you use a heat gun, or heat source like it, the plexi when heated will move towards the heat source so (molecules expanding, etc.), so heat on the side of the "outside" of the radius. It helps a bit as it slightly comes toward the heat.
I have a welding fab shop so I clamped 2 pieces of angle iron on the bench far enough apart that when I bent the plexi to fit inbetween them, I had about a 10'' "bow" in the glass from the bench to the plexi. That works way better than doing it by hand!! I then started heating the plexi a the the outside end first, where there is more curve. It took a long time as I am not familiar with how much or how hot it needs to be but, I did also use a temp gun and found that somewhere around 250*, or so, seems like about where it needs to be. I did have a small spot of distortion on the first window where I heated it a bit too much.
My buddy Rusty helped me install them. I used 3M urathane sealant to seal the gasket to the flange of the bus. Tip - If you cut off just a small amount of the tip of the sealant, you can stick it into the 1/8'' groove of the gasket and put a small bead in there for when you slide it onto the flange and it will keep the mess to a minimum, and this is some good sticking stuff that is a bit tough to get off!! (don't ask me how I know )
You need the correct tools to install the window and bead. They are cheap from Amazon.
We found it easiest to start at opposite ends (Catty-corner) of each other. YMMV here but that worked for us. Be sure to use soap water as well.
Well, that is as "Cliffs Notes" of a version as I can make my explanation. I'm no great literary figure so I hope you all understand this. I would attach a couple basic pix if I saw how but, I don't. I'll do another post for them so I don't screw this up and spend another 1/2 hour typing with one finger.
Later guys.........

Don't ya just love it when a plan comes together! Glad I was able to help a little anyway. 

[Chaz]

So here is how they look. Disregard the black around the windows, it is epoxy paint. I want to coat the top with some sort of "paint" or whatever would be best. I have seen some products but have not checked out anything yet.

[dtcerrato]

Looks awesome Chaz! Nice work!

[buswarrior]

Did you have fun doing this?

'Cuz there's others who will want to pay you well to do the same to their buses.

Don't work for cheap...

Happy coaching!
Buswarrior

[Chaz]

  HA HA!!!!!
Buswarrior, that's pretty funny as I and Rusty talked about this and laughed.
It was an absolute "BEAR" to do but, since it was my bus and needs paint, it was easier than someone who has a finished bus.
To be completely honest, I LOVE, truly love helping people but, this is a project that I am scared of. The amount of work and still the possibility of a leak..... scares me.
And as far as working cheap.... have you been talking to my friends and girlfriend??  I get a lot of grief for not charging enough. Seriously. I have a problem with it. I don't like to charge friends......and everyone is my friend.  (If you only knew JUST how accuraate your statement is, truly, it's tooooo funny!!!  )
Thanks for the compliments tho. We will find out today if it works. We are supposed to get some fairly good rain for the next few days. I will be monitoring it.
Now, if anyone would need some repousse' work done.... I can hook you up!! If you are not familiar with it, my site - www.amstudio.us has some on there as well as my Facebook page - Chaz's Aesthetic Metal Studio. I did a GMC badge for the front of a guys bus from Florida. (He said it was too nice to put on it. )
Anyway.............
Ultimately, I hope someone else can use this info as I have gotten a LOT of help from you guys and want to contribute where I can.
Thanks.
Chaz

[chessie4905]

guess someone may want my pair of Vista window takeout. Can't use on mine. When converted, they put on an Eagle cap and built a nice cupboard inside to utilize the space, so no going back.

[Chaz]

Dang Chessie, I would have if I knew you, or someone had both. I thought only drivers sides could be found.
Dang.

[luvrbus]

guess someone may want my pair of Vista window takeout. Can't use on mine. When converted, they put on an Eagle cap and built a nice cupboard inside to utilize the space, so no going back.

Hum a Eagle cap on a GM gives you class John 

[chessie4905]

No, it will cause rusting issues.😂

[buswarrior]

No, it will cause rusting issues.😂

Or, it was installed to hide a rusting issue...?

Chicken or the egg?

Happy coaching!
Buswarrior

[chessie4905]

not on mine.

[BusNit]

So well worth the effort. That came out spot on! Looks factory and the plexiglass will take a beating.