Lexan question

All about making her shine

Moderator: John_Heard

Message
Author
User avatar
Bruce69Camaro
Posts: 1799
Joined: Thu Jul 23, 2009 11:07 am
Location: PA

Lexan question

#1 Post by Bruce69Camaro » Mon Mar 11, 2013 6:40 am

My coworker bought some 1/8" lexan and made his door windows for his Mustang.

He got everything mounted and came out the next day, to find spider web cracks around the holes that he drilled in the one window.

So he made another one, but this time, used a hot tip to make the holes and the same thing happened.

Anyone ever have this problem?
Those who think they know it all have no way of finding out they don't......... :scratch:

DOTracer
Posts: 466
Joined: Tue May 24, 2005 11:12 pm
Location: Westminster, MD

Re: Lexan question

#2 Post by DOTracer » Mon Mar 11, 2013 9:30 pm

Don't go very tight with the screws. Typically that causes the panel to warp anyway.

You absolutely sure it was lexan he has? I once bought a piece from Home Depot and turns out it wasn't Lexan, but another form of clear plastic and it cracked very easily. Lexan you can shear and bend on a sheetmetal brake and it won't crack.

User avatar
Bruce69Camaro
Posts: 1799
Joined: Thu Jul 23, 2009 11:07 am
Location: PA

Re: Lexan question

#3 Post by Bruce69Camaro » Tue Mar 12, 2013 4:51 am

It was a 4' x 8' sheet of 1/8" lexan from a local business that our company deals with and he said the same thing, he could bend it, twist it and it wouldn't break, but he drill's holes and it cracks.

He told me he gave up and put the glass back in.
Those who think they know it all have no way of finding out they don't......... :scratch:

DOTracer
Posts: 466
Joined: Tue May 24, 2005 11:12 pm
Location: Westminster, MD

Re: Lexan question

#4 Post by DOTracer » Tue Mar 12, 2013 6:18 am

Well if it truly was lexan the only reason for it to star crack around the screws is either he tightened the screws way too tight, or it was a flat sheet and he was trying to force it to bend into a shape and using the screws to hold that curvature.

I myself don't care for using flat sheet in cars. it rarely looks correct and just makes the job look cheap when done.

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#5 Post by John_Heard » Tue Mar 12, 2013 7:49 am

Sounds like he was using Plexiglass, not lexan.

Todd I used 1/8" flat sheet in my door and rear windows, I think it turned out real well and I don't think you would be able to tell it's not prebent. What I did learn is that marguard stuff really does make a big difference in scratch resistance.

Image

User avatar
Bruce69Camaro
Posts: 1799
Joined: Thu Jul 23, 2009 11:07 am
Location: PA

Re: Lexan question

#6 Post by Bruce69Camaro » Tue Mar 12, 2013 8:47 am

John, that car of your's is so nice.

I wish I could actually see and hear it run sometime.

We actually have used polycarbonate or lexan here in the lab to make a combustion chamber wrapper for one of our heat exchangers and I had no issues drilling and screwing it to the boiler. He got this lexan from the same supplier that we have used before. Maybe there was something defective in the material??

I asked him how tight he made the bolts and he said they were hand tight.

He made his windshield and rear window out of lexan, he just didn't have luck with the side windows.

Who know's, it's another unsolved mystery......
Those who think they know it all have no way of finding out they don't......... :scratch:

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#7 Post by John_Heard » Tue Mar 12, 2013 9:34 am

Thanks - I'll try and get some video this summer...

Lexan shouldn't crack like that, so something is weird with that material he had...

User avatar
supernova
Posts: 2552
Joined: Sat Feb 02, 2008 7:35 pm
Location: Ft.Worth Tx

Re: Lexan question

#8 Post by supernova » Fri Mar 07, 2014 10:44 am

Hey John,
I have glass doors from Glasstek and bought all the Tim McAmis hardware to mount and open and close the doors but I can't swallow the price for the windows.
What did you use for windows and where did you get it?
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#9 Post by John_Heard » Fri Mar 07, 2014 10:59 am

I just bought a 4x8 3/16" thick sheet at Regal Plastics. I used that to make everything except the front window. $154 w/tax.

It is NOT scratch resistant, but I figured for $154 bucks compared to the Maurgaurd prices, I can afford to change it out often and still come out ahead. The Maurguard is better, just pretty expensive compared to regular lexan sheet.

They probably make scratch resistant sheets but probably double price? I didn't look into that at the time.

User avatar
supernova
Posts: 2552
Joined: Sat Feb 02, 2008 7:35 pm
Location: Ft.Worth Tx

Re: Lexan question

#10 Post by supernova » Fri Mar 07, 2014 11:06 am

Thank you for the info.
The 3/16 laid down and curved ok I guess? I'm only using it on the sides. The front and back glass was professionally installed so I'm leaving in for now.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#11 Post by John_Heard » Fri Mar 07, 2014 11:48 am

Yeah, the 3/16 isn't bad for curving really at all. I'm just using stock window felt in the channels. It's not super obvious the side windows are lexan.

User avatar
Bruce69Camaro
Posts: 1799
Joined: Thu Jul 23, 2009 11:07 am
Location: PA

Re: Lexan question

#12 Post by Bruce69Camaro » Wed Jan 20, 2016 6:41 am

Bringing this thread back alive...

John, question about your windows.

Did you use 3/16" for the rear window or 1/8"? I saw you mentioned both sizes but wasn't sure what you used.

I see that you reinstalled the window trim, which I want to as well.

What butyl tape did you use and did you have to go with a thicker tape or was is standard?

Were you able to get away with just using the tape or did you have to put some screws in as well?
Those who think they know it all have no way of finding out they don't......... :scratch:

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#13 Post by John_Heard » Wed Jan 20, 2016 7:51 am

I used 3/16, regular butyl tape and screws. Worked fine.
Bruce69Camaro wrote:Bringing this thread back alive...

John, question about your windows.

Did you use 3/16" for the rear window or 1/8"? I saw you mentioned both sizes but wasn't sure what you used.

I see that you reinstalled the window trim, which I want to as well.

What butyl tape did you use and did you have to go with a thicker tape or was is standard?

Were you able to get away with just using the tape or did you have to put some screws in as well?

User avatar
Bruce69Camaro
Posts: 1799
Joined: Thu Jul 23, 2009 11:07 am
Location: PA

Re: Lexan question

#14 Post by Bruce69Camaro » Wed Jan 20, 2016 9:09 am

I believe Chris asked this, any issues with flexing?
I was going to wait till it was hot out, cut the pattern and tape it to the glass window and sit it in the sun to heat it up and form the shape.
How much wider all around did you make it or didn't you?
Thanks
Those who think they know it all have no way of finding out they don't......... :scratch:

User avatar
John_Heard
Site Admin
Posts: 5734
Joined: Thu May 12, 2005 11:20 am
Location: Resume Speed, Kansas
Contact:

Re: Lexan question

#15 Post by John_Heard » Wed Jan 20, 2016 9:47 am

Yes, the 3/16 windows will flex some on the side and rear. I haven't noticed the front doing it very much though. I suppose that's because of the curvature of the front window.

I'm pretty sure I used the old window for a template, we cut it to rough size then clamped it to the old glass window around the outside and marked it. It might have ended up slightly larger, I know I wanted to have enough room to get the screw heads in there without them showing. Better to cut it big to start with then trim down if necessary.

Post Reply

Who is online

Users browsing this forum: No registered users and 17 guests