Trimmed my windshield and well, it melted...

[FutureVentures]

Ok so, I bought a new jigsaw and blades just for trimming/lowering my wind screen(any excuse for a new toy).

 

Marked off a nice arc, oddly enough using the chrome plastic screen trim as a template worked well.

 

Started jig-sawing away and it was going great, clean line, cutting quite nicely to mid-point. Then had to remove the blade from the screen to switch to the left side. Shoulda let the blade stop first I guess, made a little gouge but, no biggie.

 

Starting from the left, it cut through quite nicely again till I reached the arc I had already cut from the right side. To my surprise, the cut piece didn't fall away, as it should have....

 

Apparently, that lil blade was quite hot and as I cut the left side in towards middle, it was melting the plastic and the sucker very effectively reglued itself to where I just cut it from, if that makes sense. So firm that, I couldn't break it free, for fear of breaking too much.

 

Tried again through where I just cut and it melted/reglued still! Had to hold the plastic screen away as I cut, to finally get the pieces to release.

 

Much sanding was needed to get it all smooth, pics later. It looks good.

 

Soooooo, did I have the saw on too high a speed or should I simply take breaks as I go along?

 

The first cut on the right side worked great, the 2nd cut from the left is where things got....hot.

[RandyR]

sounds like maybe the blade got a bit dull. that could explain the heat.

[SilvrT]

I'd say you run the saw too high speed and moved too slow. Not sure what kind of blade you used but mine was a very small blade with lots of teeth for very fine cutting. Been a while since I did mine but I'm pretty sure I ran it about 1/2 speed and I moved the saw forward as quick as I could. Never had any of the "melting" issues you mention.

 

Main thing is tho...that you "got 'er done".

[Snaggletooth]

Yeppers. Too high of speed. Use a very fine tooth blade on a low speed and let the saw do the work. Use no more pressure than the saw needs to move forward. Always try to do the cut in one move if possible and let the blade stop moving before pulling it out. It helps to have an extra pair of hands to hold the top section from binding on the blade to.

 

Using painter tape on the shield will help keep the shield from getting scratched while cutting to.

[Jerry W]

I have never had plexiglass get hot enough to stick back together, but I always tape both sides before I cut it and use a medium tooth blade. Your blade could have been a little too fine, but you got it done.

[SilvrT]

I stand corrected... the blade wasn't as small as I thought ... but it is a "fine cut" blade.

[LilBeaver]

Maybe you got your shield mixed up with one of the shields that are made by the same people that make the trick birthday candles that relight themselves

[frogmaster]

18 teeth per inch works very well. you might have a slight (tilt or skew) because you went to your weaker back hand side thus causing more heat. Slow and steady don't push it, the 18 teeth per inch is "Fine" enough and coarse enough to get fresh/cool air into the cut too. Done 2 of them so far .

[VentureProf]

Also, a spiral saw with a laminate cutter bit works great although it can run wild on you if you are not careful. That's what I used to cut my shield for a GW vent. Very clean cut.

 

Kelly

[V7Goose]

Yes, your saw was set on too high a speed. When cutting plastic, use a hollow ground blade (plywood), and set the saw just fast enough to prevent vibration.

Goose

[FutureVentures]

Yeppers. Too high of speed. Use a very fine tooth blade on a low speed and let the saw do the work. Use no more pressure than the saw needs to move forward. Always try to do the cut in one move if possible and let the blade stop moving before pulling it out. It helps to have an extra pair of hands to hold the top section from binding on the blade to.

 

Using painter tape on the shield will help keep the shield from getting scratched while cutting to.

 

Okay well, since the shield I cut yesterday was previously messed up it is now TOO short for long rides, perfect for summer though. It does look dang sharp though, low boy style.

 

 

 

So today, I'm cutting down the HUGE stock shield and will reduce my saw/blade speed, I had it at max. Doh!

 

I'll try straddling the front wheel and see if I can then make it in one cut.

[T.J.]

You can use "Paraffin Wax" for canning. When we cut Aluminum or Plastic here at the shop on the band saw we always coat the blade with the wax. It stops the chips from sticking to the blade and therefore keeps it clean and cool.

Been doing that for years. Paraffin wax also works well when you are melting lead for making bullets. You drop a small piece into the lead once it is hot and it will bring all the nonconformities to the top so you can scoop the junk out.

Injoy the weekend if ya want to.

[FutureVentures]

Maybe you got your shield mixed up with one of the shields that are made by the same people that make the trick birthday candles that relight themselves

 

I was beginning to wonder! Thought I was in the friggin twilight zone for a while, that sucked re-adhered in a jiffy, lemme tell ya.

[TIMEtoRIDE]

After cutting, I finished the top edge with a cut-off disc in an angle grinder,

followed by hand sanding with a foam block sander.

You can then get a factory look by wiping with acetone, but I'm not that brave !

[SilvrT]

I was beginning to wonder! Thought I was in the friggin twilight zone for a while, that sucked re-adhered in a jiffy, lemme tell ya.

 

Look at it this way... you've just become a magician ... you can cut a windshield without cutting it LOL

[SilvrT]

After cutting, I finished the top edge with a cut-off disc in an angle grinder,

followed by hand sanding with a foam block sander.

You can then get a factory look by wiping with acetone, but I'm not that brave !

 

I used a file to smooth mine .... had several comments that it looks "factory".