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Wed Nov 05, 2008 1:18 am

I have a Split sunvisor with wavy plastic. Does anybody has any tips how to make it straight again? I'm afraid if I would repop a new one, the the rivets are not going to look the same as the original.
For now I have warmed the thing up a bit with a hairdryer and clamped it between two thick wooden planks and put it on top of the heater element in our house (which is only luke warm).
Any other tips?

Wed Nov 05, 2008 1:26 am

Warm it up with your hairdryer till it is straight, after that put a wet towel on it with a heavy Stone on top , That will help !

Guido

Wed Nov 05, 2008 9:21 am

You mean that it will straighten itself by warming it up?
I warmed it up a little and the only thing that happened was that the plastic got softer.
What's the purpose of the wet towel?

Wed Nov 05, 2008 10:49 am

I've never tried this with a visor, but other plastic things

hot water. Hot tub or whatever, like 100degrees. then place between flat heavy objects, like books. the hot water should make it heat evenly, wear a hair dryer will not

Wed Nov 05, 2008 11:04 am

i have the same problem with a double side visor for my 58 ragtop. the best result might be hot water or sun exposure on a very hot day, the wet towel is that the plastic cools evenly.

a hot air gun should do the same trick, but making sure the plastic does not melt. i believe that also the plastic should cool gradually to avoid small inner cracks.

Wed Nov 05, 2008 11:13 am

I did this maybe 100 times with plastic Bumpers , I heat them up with a hot air gun and push it back in shape , and then cool it off with a lot of cold water ! If you would try this, cool the spot on both sides together for the best result ! I know you don't have plastic bumpers on your beetle, but maybe (I'm almost 100% sure) on your daily drivers !
I also did this with sunvisors, Heat it up , put a wet (cold) towel and a have weight, the sunvisor will not crack from the cold towel or water !

Guido

Wed Nov 05, 2008 11:14 am

To straighten things out I soak it in cider or a mixture of water & Viagra :shock: :wink: :lol:

Wed Nov 05, 2008 4:46 pm

in cider :wink:

Wed Nov 05, 2008 5:29 pm

I make the red popes nose lenses by cutting the 1/16" red acrylic to template, then immersing it in boiling water to bend it to shape. The water has to be right at boiling, or it does not soften sufficiently.

Not sure how the melting temps of the perspex that they used on the visors compared, but it might be worth trying with some "junk" visors (there seems to be plenty of those around).

Interesting idea for sure...

Wed Nov 05, 2008 9:09 pm

I would do this.

Put it on a flat pan inside your oven. Heat it to about 200F and watch gravity flaten it out. Then let it cool.

Make sure nothing you put in the oven can be damaged from the heat.

Thu Nov 06, 2008 1:30 am

tazm wrote: I know you don't have plastic bumpers on your beetle, but maybe (I'm almost 100% sure) on your daily drivers !
Guido

I have a 1974 Beetle as a daily driver --> steel bumpers ;)
The newest car I've ever had was a 1977 VW Scirocco GTI (also with chrome bumpers).
Plasic is made of oil and oil should only be in your engine/gearbox :D
I like bakelite though ... :)

Thu Nov 06, 2008 6:55 am

Re-riveting a new piece is not that difficult really, especially if you use an aluminum rivet in place of steel rivets that I've seen more commonly used on split visors. The aluminum rivet head will give very easily and give you the correct look.

If you have a decent rivet setter tool to rest the rivet head into you will have good results, or make one by drilling a little "bowl" into the top of a sacrificial hex head bolt, and then put that bolt in a vise as your new post rivet setter. Grind/sand/round the hex head sides and top so it fits within the contours of the visor bracket (wrap a bit of electrical tape around the bolt head so you don't ding and scratch up the aluminum bracket, etc, then you are done, works great.

So thats my first suggestion if you have a decent acrylic/perspex substitute to install, first because it'll give you hours back in your life, plus you have a new tool in your box.

If you have hours to spare though, and love experimenting, wishing, hoping, praying, shouting 4 letter words in the kitchen, etc., then have a go at the applied heat approach. Working out the waves/warps in 50+ year old acrylic will yield very unpredictable results though. No two visors are going to react the same, and each will have essentially baked itself out over those years as well. Try applying some low heat first in one small area to see how your particular visor is responding to the heat first, the lower the heat the better, keep an eye out for the color changing too much though. Gravity will do some of the effort, but a lower temp is better with some applied flat pressure to mitigate other color problems resulting from higher heat. Plastic is not like wood though, so nomatter how long you might clamp it once plastic has had its elastic limit changed you have to try and move it back by the same methods that changed it the first time, which is mostly heat. 50 years on though I wouldn't expect great results however. Good luck and would love to understand your results so everyone can learn from it.

Gary

Thu Nov 06, 2008 11:49 pm

Erik G wrote: I've never tried this with a visor, but other plastic things

hot water. Hot tub or whatever, like 100degrees. then place between flat heavy objects, like books. the hot water should make it heat evenly, wear a hair dryer will not

Well I've put the sun visor in a bath that I filled with boiling water, while it was pressed between two wooden planks, but now it is destroyed. The plastic couldn't handle the heat and changed into a funny color.
I guess I have to repop this one. But how can you repop it so nicely? The heds of the rivits are nice and round on both sides. Is there some special vice grip on the market to repop those rivets?

Fri Nov 07, 2008 4:16 am

I also noticed that this sun visor is flat at the bottom, while the optional R/H sunvisor I have, has some kind of ridge at the bottem, likely to reinforce the plastic.
Could that be the difference between Split sun visors and Oval sun visors?

And what about Split mirrors and Oval mirrors, are those the same?