Making My Own Clear Headlights from Lexan

[SubaSteevo]

Originally Posted by 94SubieSVX

Got a bit done. Here's a few pics of what I did.

Here's the frame holding the lexan in it. Made it just like a video posted earlier in this thread.


Here's the setup. The oven is just out of the picture to the left, close enough that the lexan doesn't get hard once out of the oven.


The first frmae holder setup. I had to raise it about 3 inches more to allow for the sagging lexan.

I had made a 95% perfect mold at first, but two corners weren't up against the plaster mold good enough. So I raised the plaster mold about 1/2" and re-heated the lexan again.

This is what happens if you re-heat the lexan multiple times at about 375degrees and leave it in for too long. It had sagged so much that it started coming out of the frame and was so long that it got wrinkled as you can see.

I'm going to start fresh with a new piece and make sure to watch it before it sags too much.

Why are you heating it up so much? All the information we've passed on says to heat it up to 200-250ish. 375 is definitely too high.

[94SubieSVX]

Originally Posted by SubaSteevo

Why are you heating it up so much? All the information we've passed on says to heat it up to 200-250ish. 375 is definitely too high.

I started out at 200, nothing, then went up by 25degree increments for at least 5 minutes. Once I hit 300 it actually started to get soft. Once I hit 350 it was starting to sag, so I let it stay there for over 10minutes, but it just wouldn't get stretchy enough. So I put it at 375 for less than 5minutes and it got stretchy enough. I tried it multiple times by heating, forming, not getting a good form, then re-heating. I did that about 3-4 times and it wore out the lexan, then finally it just gave up and sagged an incredible amount(as shown in the pic by the overlaps).


- And I had left it in at 200-225 for at least a half hour before I upped the temp.

[SilverSpear]

Try the process once more, but leave it at 250 for a long time. let it soften at that temperature and take as much time as it wants.

Let us know how it goes then.

[superru]

hey man, how'd the shop vac work?

[94SubieSVX]

Originally Posted by SilverSpear

Try the process once more, but leave it at 250 for a long time. let it soften at that temperature and take as much time as it wants.

Let us know how it goes then.

Will do, I don't have work til 5pm tomorrow so I have all day to mess with it.

Originally Posted by superru

hey man, how'd the shop vac work?

My lil' 1.5hp shop vac actually worked pretty good. Once the lexan was heated enough it sucked pretty well.
I just gotta seal up the little holes that seemed to work their way into the framework.

[crazyhorse]

Originally Posted by 94SubieSVX

I just gotta seal up the little holes that seemed to work their way into the framework.

Quick tip....Chewing gum!

[94SubieSVX]

Originally Posted by crazyhorse

Quick tip....Chewing gum!

Sweet deal thanks!

[demonsvx]

Check out this website http://www.instructables.com/ and type in vacuum forming and there is information on how other people have done it. Hope this helps

[94SubieSVX]

Originally Posted by demonsvx

Check out this website http://www.instructables.com/ and type in vacuum forming and there is information on how other people have done it. Hope this helps

It did help, alot actually.

After the last attempt at forming with the same thickness lexan, I've come to the conclusion that I need thinner lexan. And on the website "instructables" there was a link to www.usplastic.com which has thinner lexan, and for cheaper than what I'm paying now also.

Even though everybody was generally saying not to heat it up above 300degrees, one of the descriptions said that lexan forming temp. is around 375 degrees. That's the temp that it actually started to get stretchy enough to mold. The only thing that is setting me back is that everytime I mold it at that temp the bubbles start to gather in the lexan.

Hopefully with the thinner lexan, I can soften it up at a lower temp, and also avoid getting the bubbles in it.

The thickness I have now is .093". I was looking at getting either .060" or .050". I was thinking I'll go with the .060" because it's not too thin or thick. Though Smallcar uses .090".

[superru]

So whats the update?!! anything new?

[94SubieSVX]

Nothin yet, X-mas was pretty hectic. I'm gonna be ordering thinner lexan soon though.

[SVXRide]

Originally Posted by 94SubieSVX

The thickness I have now is .093". I was looking at getting either .060" or .050". I was thinking I'll go with the .060" because it's not too thin or thick, it's just right.

Ah, the "Three Bears" approach to lexan selection!
-Bill

[Hocrest]

Bill, I was thinking about this over the weekend... Back when I worked in the medical business, for a time we supplied custom molded supports and back braces. These had plastic inserts that we would heat and mold to the patient then slip them into the cloth covers.

To heat them up we used an electric griddle like this;


The nice thing about it was that you it had a temperature on the dial that you could set it to, and know that the plastic would get to that temperature and not go over.

Not sure if this info is helpful??? Just a thought I wanted to pass on.

[94SubieSVX]

Hmmm...an electric griddle. That sounds like it could work.

Thanks Dave, I'll have to search for mine

[SubaSteevo]

Originally Posted by 94SubieSVX

Hmmm...an electric griddle. That sounds like it could work.

Thanks Dave, I'll have to search for mine

And if it doesn't work then you can make yourself some eggs!