Jump to content
Model Cars Magazine Forum
Lovefordgalaxie

Replacement windshield heat formed

Recommended Posts

that seems like a worthy idea to try, it would resolve the problem of melting through the plastic with the heat gun or flame.

It's a good idea, but it will give you a lot of work. Why? because the key to this working, is to control where the heat goes. You have to heat only the area around the mold. Water will lack this kind of control.

Other thing: I never tested, but I think 100 degree Celsius is not enough to do the job. And that is the temperature of boiling water.

Share this post


Link to post
Share on other sites

i did this once in the 90s to make a new rear window for a 1964 fury. instead doing the way you did it i made a two part mold out of bondo and then press the new window out

Share this post


Link to post
Share on other sites

This is a cool idea and doesn't seem too complicated.

I see that the original windshield is used to make the mold, but is it in place when you use the torch to form the bottle to the new windshield? I feel like it would be a melted mess to pull apart otherwise. 

Thanks for any help!

Share this post


Link to post
Share on other sites

I successfully used this method for windshields for late 50's Chrysler products. Specifically the 57-58-59 Dodge and 59 Plymouth. I used my heat gun set on low and continually worked it over the plastic until it formed perfectly. Came out perfect. 

 

Share this post


Link to post
Share on other sites

I have a 57 Chevy stepside that was going and looking very good until I decided to check the windshield fit. It is too small from top to bottom and the side to side is a little out also. This way of making one will get me back to going and finish it. Thanks for the idea and showing how to do this. Since finding this bad part, I have been checking the windshield fit on the body of every one built since this find before I even start. I am just a average builder that likes to build out of the box models. No cutting and shaping except for bad fitting parts.

Richard

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Share this post


Link to post
Share on other sites

I have a 57 Chevy stepside that was going and looking very good until I decided to check the windshield fit. It is too small from top to bottom and the side to side is a little out also. 

Richard, the problem isn't with the windscreen per se, it's that AMT messed up and didn't model in more real estate around the frame itself.

Take a look at this pic here...................note the slight overhang on the roof header.............

ebay143989950486574.jpg

A you can see, there should be more sheet metal around the frame supporting the glass, as it should fit from the outside the way AMT intended, but made a goof. You can either mold the glass larger, or take some plastic and build up the A pillars and header to hold the glass.

Hope this helps!

Share this post


Link to post
Share on other sites

Thanks Bill for the photo and info. With my modeling skills, I think I would make more of a mess by adding some styrene around this than just making a windshield that would fit better. 

Thanks

Richard

Share this post


Link to post
Share on other sites

Great tutorial! I have a 69 Camaro I parted out because of the cracked windshield. The body may get new life now! Thanks.

Share this post


Link to post
Share on other sites

Old thread, but good info! I may have to do this for a project I am working on. So what type of glue works best with the PET (polyethylene terephthalate) plastics?

Edited by NOBLNG

Share this post


Link to post
Share on other sites
12 minutes ago, NOBLNG said:

Old thread, but good info! I may have to do this for a project I am working on. So what type of glue works best wit the PET (polyethylene terephthalate) plastics?

See if you can find Bill Geary's thing on doing the pillars so the "glass" just snaps in. Otherwise, if it's fitted carefully, white PVA glue works great. Or clear epoxy if you want to play with it.  ;)

Share this post


Link to post
Share on other sites
11 minutes ago, Ace-Garageguy said:

See if you can find Bill Geary's thing on doing the pillars so the "glass" just snaps in. Otherwise, if it's fitted carefully, white PVA glue works great. Or clear epoxy if you want to play with it.  ;)

Question Bill.....

Whats your say on that "purple light" instant bond adhesive......for this application? 

Share this post


Link to post
Share on other sites
3 minutes ago, Khils said:

Question Bill.....

Whats your say on that "purple light" instant bond adhesive......for this application? 

I have no first-hand experience, though several guys on here have.

Share this post


Link to post
Share on other sites
13 minutes ago, Khils said:

Question Bill.....

Whats your say on that "purple light" instant bond adhesive......for this application? 

I've tried it to hold glass in and while it doesn't seem to fog the glass, it does need to go on a rough surface for a mechanical bond so I wouldn't use to glue glass directly, But if the glass has an overlap on the body that is hidden from the exterior you can run a bead of it along the edge of the glass onto the scuffed up body with just enough over the edge to hold the glass in place. Think of those little triangle sticker things you get to hold photo corners and you'll maybe get the method I'm trying to explain

Share this post


Link to post
Share on other sites
2 minutes ago, stitchdup said:

it does need to go on a rough surface for a mechanical bond

I'm following you completely!     Have had the idea for awhile.....just haven't put it to project.

Really like the idea of NOT adding the UV.....til it's exactly where I want it.  Thank you!

Share this post


Link to post
Share on other sites
1 minute ago, Khils said:

I'm following you completely!     Have had the idea for awhile.....just haven't put it to project.

Really like the idea of NOT adding the UV.....til it's exactly where I want it.  Thank you!

I'm glad it made sense, I know some thing s can get lost between American English and British English

Share this post


Link to post
Share on other sites

Thats a great tip. Thanks for the info. Have to give it a try have.

Share this post


Link to post
Share on other sites
Posted (edited)

Heat forming, vs. Vacuuming, it's all the same principle. You must have a molding buck that is strong and sturdy. 

Below are some molding bucks I have made. The dome was for the Pontiac Banshee. It needed a riser, so the new copy wouldn't flow into a horizontal plane on the vac table. Even if you used a heat gun instead, a riser is still a good idea. Notice I drilled holes for vacu forming (not neccessary for heat molding).

I didn't have epoxy putty, so I made a plastic buck for a chopped Bonneville windshield buck. I photographed it over a mirror to show both sides. Looks like I never did finish the surface, as it should be sanded smooth. Note the strengthening ribs on the inside. 

HTH.

20190412_103906.jpg

20190412_103917.jpg

20190412_103815.jpg

20190412_103759.jpg

Edited by Jon Cole

Share this post


Link to post
Share on other sites

I did something similar for an AMT 1/16 '55 Nomad kit that had been on the shelf for 30 years and had a broken w/s.  I glued it back, but made a casting from inside (concave side) from Durham Rock Putty, a home repair material that mixes with water.  Then I 'drooped' a new w/s using shirt-box plastic (don't know what it really is) using a heat lamp.  First try was' close but no cigar', second attempt came out just fine, and helped save the kit.  Next is a replacement w/s for a die-cast 240Z w/s, which must be saved because the car is repainted silver like my '71 and is signed by Datsun legends Pete Brock and John Morton!  I may add my sig, as I wrote HOW TO RESTORE YOUR DATSUN Z-CAR, a new revision of which is coming out this year!  :-<)  Aw, shucks...!

Wick Humble

Share this post


Link to post
Share on other sites
On 4/12/2019 at 10:54 AM, Jon Cole said:

Heat forming, vs. Vacuuming, it's all the same principle. You must have a molding buck that is strong and sturdy. 

Below are some molding bucks I have made. The dome was for the Pontiac Banshee. It needed a riser, so the new copy wouldn't flow into a horizontal plane on the vac table. Even if you used a heat gun instead, a riser is still a good idea. Notice I drilled holes for vacu forming (not neccessary for heat molding).

I didn't have epoxy putty, so I made a plastic buck for a chopped Bonneville windshield buck. I photographed it over a mirror to show both sides. Looks like I never did finish the surface, as it should be sanded smooth. Note the strengthening ribs on the inside. 

HTH.

20190412_103906.jpg

20190412_103917.jpg

Just seen your post Jon! I like the idea of how to handle the bubbletop in the Pontiac Banshee. That's what's held me back from ever building that kit............I absolutely hate the severe distortion the kit glass has as with the actual car, that's the main focal point of that car. Crystal clear glass with a distortion free view.

I could either vacuform it as you've shown, or cut the glass apart (carefully!) and sand and polish out the glass as the model would have opening doors. Much easier that way than trying to sand the inside of that bubble. Thanks for the tip!

Share this post


Link to post
Share on other sites

You can get Epoxy putty just about anywhere you can get automotive supplies, it's usually a stick shaped two part material sold for patching just about anything from gas tanks to boat hulls (there big thing here is it can even be applied underwater. I'll even bet if the backside of your piece is really smooth and you were to apply a liberal coating of wax or my old standby, liquid dish soap or heat some petroleum jelly until it's a liquid and dip your piece into it before applying your epoxy, or whatever you want to use, Cold Bond is thinner and easier to make it smooth out on the backside of your original paet. You would come up with an undersized positive for molding your usable part over and wouldn't have to worry about it being on the big side due to it being the thickness of the clear material oversize...BUT just an idea for you to think about.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...