Keith, something as smooth as glass will be relatively simple to prepare. Wax the glass with a few heavy coats of carnuba wax and buff off. Fiberglass mat can be purchased at various stores and ranges in weight from very fine, almost like silk, to very coarse, called roving. You will want a mid-weight fabric, I would recommend a 2.0 oz chopped strand mat. The resin can be bought at any home products store (HD, Lowes, etc), 1 quart should be enough for a windshield but you could buy a full gallon if you think that you will use it again. Here in San Diego we have a number of fiberglass supplies shops due to the large number of boats in the area...perhaps you have a specialty shop in your area as well that you could go to so that you could get the resin and the mat at the same store.
The process...once the glass has been waxed, lay a sheet of the chopped strand mat over the glass and smooth it out. Cut off the overhanging mat but leave yourself a little (maybe 2 inches around the edges). You will need two layers of mat to make the fiberglass part strong enough to hold its shape, so make another piece of mat now before you mix the resin so you won't have to stop mid-stream. Chopped strand mat will appear to be very stiff when you buy it, but when you start applying resin the binding agent in the mat will break down and it will becoms VERY pliable and easy to mold around the curves. The mat does NOT have to be in one piece, you can use odds and ends to patch together a layer as you apply the resin.
OK, so now you have the 2 layers of mat cut, you have your quart of resin, a 2-3 inch chip brush, a small pail or cottage cheese container to mix the resin in, and you're ready to start. Mix the MEK hardner with the resin as instructed on the resin can, only mix half the resin now so you have some to work with later. Lay the first layer of mat onto the windshield and brush the resin mixture over the mat, coating it thoroughly. The mat will turn transluscent as it absorbs the resin. When the first layer of mat is coated then lay on the second layer, pressing the mat down with your brush until it soaks up the resin from the first layer. If you have dry spots in the second layer then add resin as necessary to get it all coated...push out any bubbles as you go. A good point to remember...resin does not add strength to a fiberglass part, it only binds the fibers together. What this means is that once you have enough resin applied to the chopped strand mat to cause it to turn transluscent, then stop applying resin...any more will just make the part heavy and weaker.
OK, now you have the 2 layers of mat layed up...what next? Depending on the weather and/or air temperature, you can expect that the resin will "kick" in about 15 minutes. This is an exothermic material meaning that it will give off heat (just like Bondo)...when it is cool, it is set. I would suggest that you leave the part on the windshield overnight to let it cure. When ready, start prying the fiberglass part away from the windshield by working it at one corner...as soon as it starts to give it will pop right off in one piece. A word of caution, remember that mat that you left overhang the edge of the windshield...if it is curled around the edge of the windshield, now that the fiberglass has cured, it may hold the part to the windshield and not allow it to seperate. Without trying to get too technical I'll tell you that there is a phase called the "B" phase in the curing process of the resin where you can easily trim these edges with a simple pair of scissors or box cutter. The "B" phase occurs just after the resin starts to "kick"...if you are used to working with bondo, this is the time that you would use a "cheese grater" to shape the bondo. The resin is hard enough to hold its shape but soft enough to cut...this phase lasts a few minutes but its a good opportunity to easily trim the excess off your new part and make the un-molding process go smoothly.
Once the part has been removed and you are over the "wow I really did this" phase, you can cut the fiberglass with various tools. Your finished part should be in the neighborhood of about 1/16th of an inch thick and very stiff. Shears or scissors will have a tendency to split the fiberglass so I shy away from those tools...instead I use a fiber cut-off wheel and my die grinder to cut the material. Wear a face mask! When sanded or cut, this stuff will make a powder that you don't want to inhale or get in your eyes.
I don't think that there is anything that you can screw up with this project, there's not much risk in the fiberglass sticking to the glass and the fiberglass will not damage the glass. Be mindful of the time, the catalized resin will kick on you before you know it so don't waste any time once you start your layup. Remember the "exothermic" property I discussed earlier...catalized resin gives off heat when it cures so if you have a quantity left over in your mixing pail go ahead and pour some water on it to prevent it from getting too hot. When I took a fiber reinforced plastics course (FRP) in school, the instructor made the students place their mixing buckets outside after they had finished their layups just in case. I think that's about it, the rest will become obvious as you "give it a go"...good luck!

 

Good description! I might add just a couple things:
resins, there are two basic types of resins used in FG work, polyester and epoxy. The polyester (PE) resin, sometimes called laminating resin, is much less expensive and is the base in most body putties. It can be recognized by the fact it comes with a relatively small container of hardener and the mixing directions tell you to use various proportions of hardener to vary the working time, (also called pot life) and on the environmental temperature. Epoxy resin will come with a container of hardener exactly the same amount as the resin or exactly 50% of the amount. The mixing instructions will call for a very specific mixing ratio of 1:1 or 1/2:1 depending on which system you have. The pot life is controlled by the system rather than the amount of hardener used. Always se the specified ratio. You can slow the cure time by the ice water bath method but not but not by a large amount of time.
pros and cons: PE is inexpensive, but continues to slowly cure for some time, days to weeks depending on the environmental temp during which time the casting can droop and distort. After releasing lay the part back on top the windshield when not directly working with it and avoid exposing it to direct heat such as spot bulb or shop heater while not supported. The pot life can be extended by keeping the resin cool. keep the resin volume shallow by using a large shallow rather than small and deep mixing container and place the container in an ice water bath after mixing (the cold mix will be more like cold honey but will not start kicking until it warms up on the piece giving much longer pot life). The hardener is a strong solvent so mix only in a polyethelene (flexible or unbreakable plastic) or metal pail. Never in a hard plastic, plastic foam, or waxed cardboard container, it will disolve the container in a matter of minutes. PE requires the resin be separated from contact with air at the surface or it will remain sticky. This can be accomplished by covering the lamination with a layer of plastic wrap. Sometimes the resin will contain wax which will melt and float to the surface in a very thin layer to prevent contact with air, you can tell this by the directions saying the surface needs to be sanded or washed with solvent before adding additional layers to a cured laminate. In that case you can forgo the plastic wrap. I like using it in either case since I can then "work" the lamination with my hands thru the wrap if I desire. The wrap can be peeled off after the lamination has kicked.
MEK or acetone can be added to the mix to thin it slightly to make brushing or rolling easier and for cleanup.
Epoxy resin cures completely in it's given cure time and to a harder consistency than PE, therefore does not distort after unmolding, and much less sensitive to heat, but is much more brittle in handling especially if the laminate is laid up "rich" (excess amount of resin to FG fiber) It is important to use as little resin as possible to impregnate the FG, to the point where laminators will commonly soak up excess resin by rolling a roll of toilet paper over the laminate, tearing off layers of the paper as they become saturated. I prefer starting and ending the lamination with a layer of lightweight woven FG cloth with a layer or two of unwoven matt in the center to build thickness. The matt is much easier to work with while encased in cloth. I prefer to apply my resin with a 4" paint roller than with a brush. Roll a coat of resin onto the waxed windshield, and lay a layer of cloth into it, poking it against the glass with a dry brush. snip a relief into the cloth with a pair of scissors if it won't lay flat. Lay the matt over the cloth without adding any additional resin. Lay the top sheet of cloth over all. Now roll as thin a coat of resin as possible over the cloth until the sandwich is translucent all the way thru. Poke down any air bubbles with the brush. Avoid the temptation to add more resin! The sandwich should be translucent thru, but the surface should show the fabric weave not shiny puddles of resin. You can use a cardboard or bondo squeegie to spread around excess resin or move it to "leaner" areas. Don't use foam brushes or rollers tho unless you test a sample by applying a small amount of mixed resin to a sheet of corregated cardboard to see if it starts breaking down. Any brush I use I cut the bristles down to 1" long first and use with a poking or dabbing stroke rather than a brushing stroke.

 

wow thanks guys
Im on it!!

 

OK I made the fiberglass template I would not advise you to make one on a windshield you want to keep. I dont know how or why but when it dried and I pulled It away from the glass the glass was cracked top to bottom.The template fit the same as the glass IT DIDNT FIT... It seems because of the curves and the fact that It has to lay back the stock glass is not wide enough
so I cut the template down the center. Thinking that Now If I make it a two piece windshield it would fit...NOT as you can see in the pics it looks as if I will have to modify the window frame pushing it in the top corners about a
1/2". Before I go to all that trouble if any of you guys know anyone who has done this with success let me know.

 

I believe that's why when they chopped Foose's 56 they took the material out of the cowl below the windshield.

 

subscribing. This is good stuff!

 

Sorry to hear you're having trouble fitting your windshield Keith, but to me in this picture it looks as though you just need to trim off the bottom edge a bit in order to lean it back and abit of a trim on the vertical to set it in place. I was on a construction site where there were glass fitters installing mirrors and they were using a belt sander with diamond impregnated belts for trimming the glass to fit in areas that were too tight, you may want to check into getting one of those.
P.S. don't let frustration get the best of you as you have done a marvelous job thus far

 

Keth,
Have you thought about Thermoformed Polycarbonate. If you google custom formed windshield you should come up with a few options. There are shops out there that make them for bikes, boats, race cars. just another option before cutting up all that great work you have done on you truck this far.
good thread!!!!

brian...

 

That would be an option for a show only truck, polycarb is not legal for street use, nor would you really want to use it for such. It is very tough, but quite soft as well so windshield wipers would tear it up the first time you turned them on (as will just cleaning it). Thermoforming it to a compound curve will also result in significant optical distortion.

 

Keith,
Did you make your fiberglass layup off a stock windshield or did you use the one that you had already cut? From the pics it looks like you used the cut windshield, true?
I am doing a job for a customer with a chopped 56 and will be using this process to make a windshield template, what is the height of your windshield? If they are close then I may be able to help you while I'm doing this other one.

 

charlie,
Yes I used the one that was already cut but I taped some sheet metel on the corners to make it longer. In the center the height is 14"
56panel,
I know it looks close but If I cut it to lean it back more it wiil be to short and too narrow
at the top corners.

 

Today sunday I went to the LA roadster show and this truck was there, it has a similar chop to mine so I was studying the windshield. The frame was not cut but if you look inside the cab at the base of the windshield they did not use the standard rubber instead they used some kind of ???silicone?? I'm trying to think why?

 

I can't really tell from that dash shot, but it looks like the lower lip is missing..
maybe when they cut the glass they got it just a tiny bit too big , and there is no room for the gasket.. 1/4 in is all it takes.

Where did they cut the rubber to shorten it for the smaller glass?, at the top?
the ditant front shot shows the rubber down a little on the drivers side top of the glass..

I can't remember, where did you remove material? at the top?
Sam

 

That's likely done by dropping the windshield into the cowl without cutting. Can be done at top or bottom. Cut away the lip to create a slot that the windshield can slip into. Line it if desired (I would if I was doing the lower end and add a drain hose at the bottom, but then I'm **** that way). Make the channel 1/4" deeper than final drop and put ~ 3 rubber glass setting blocks in the bottom for the glass to set on. Slide the windshield down into the cowl the desired amount and match the shape with the rest of the windshield frame. Slice off the inner portion of the rubber gasket where the windshield goes into the cowl and glue the outer 1/2 to the outside of the windshield and lower frame. You could glue the inner portion to the inside after cutting away the web between to give it a factory look. Depending on chop, you could do the same at the top of the frame and slide the glass up into the header. The 56 has that tall eyebrow that could take maybe 2" of the glass. Doing the top makes it much less likely to leak. This method is commonly used for compound curved front and/or rear glass on a late model chop. If any of this is unclear, give me a shout.

 

yep, cut the body instead of the glass, and hide the extra glass top and or bottom.

that would make sense from that picture..

Sam