decided to do a wide body from scratch on my 84 fastback...my ? is whats the proper way and proper material to do this? my experience in this is above average on fiber glassing,,but not fiber glassing on smc and rim panels....just dont want to do it twice and putting all my duckies in order before i jump in with both feet......just to let u know how im thinking to do this in case u need more info on right material.....im cutting another fast back rear and spacing it out 2 to 3 inches and joining it in with existing fast back panel and continue it on rim door panel...
thanxs

nobody

SMC and fiberglass are essentially the same stuff....so any resin work on a clean SMC part should hold very well. RIM on the other hand would not bond well to fiberglass, and I don't know what would.

There are many products out to bond various body components together. Your local auto-body supply store should have everything you need.
There are SMC compatible fillers and panel bonding / fillers. Evercoat makes a product called Vette Panel Adhesive that is SMC and FRP compatible. It is what I would use to bond panels.
3M also has an automix system that is urethane based for bonding and filling various panel types together, to include the PRIM, RIM, SMC, FRP, etc...
Since you have decided to create your own, The SMC portion needs to be ground down lightly with a very course sand paper / grinder before you use any FRP. The glass Mat will work, but I would recommend an SMC compatible resin. To work with the RIM/PRIM, I would go with an automix...

Examples:





-Dave

thanxs cant wait to jump into this

Don't use regular polyester resin on the SMC panels (or the RRIM for that matter). Bond the SMC together & finish it out with the Evercoat shtuff mentioned above. If you have to use resin/mat use epoxy resin. I don't bond parts to RRIM if I can help it (the exception is my fender vents, which bond behind the fender). For my door panels I made fiberglass skins (my "Smoothie Door Skins") so that any mods I do won't crack out later.
Grind any area where you're bonding or filling with a 24 grit disc.
http://gafieroclub.org/bbs/index.php?topic=469.0
~ Paul
aka "Tha Driver"

Custom Fiberglass Parts

84's never came in a fastback.

check out the austrailian(<sp?) guy on here, he has done the same thing you want to do

this 84 does.. lol..put a 87 fastback on it....and driver as far as putting my rear extension on there will b a gap...so using fiberglass in that area is good as long as i get proper resin right? and then after fiberglassing use proper filler to smooth out right? then epoxy primer?

If you're just going to slap on the new panels over the old body & mold everything in you're going to wind up with a very heavy body. What you need to do is remove the old skin, & make a new one that's shaped the way you want it. This is why most custom folks build the shape they want, & pull molds from it & make new parts to replace the skin.
To answer your question (& without seeing your project at that point), yes you should be able to use mat & epoxy resin to fill the gap. Put something under it to hold the mat in the shape while it cures (cardboard, closed cell expandable foam, etc.). If you do make it to pull a mold from, you can use just about anything for the shape: wood, bondo, plaster, whatever - anything that you can prime over. You just pull all of that back off of the car once you make the mold.
~ Paul
aka "Tha Driver"

Custom Fiberglass Parts