55.2-59 Modifying fiberglass tonneau cover for 55-59

[56 3100]

I did a search and found a few who have done it. anyone car to share any details on modifying a hard fiberglass tonneau cover to fit a stepside. i picked up an ARE brand cover for free. after doing fiberglass dash valance and speaker panels i am fine with doing fiberglass work(over the itch!). and no i dont have the money for gaylords.

[mr48chev]

They aren't cheap but Gaylord still makes them to fit. https://gaylordslids.com/
As far as cutting an existing one down, I am going to say that is totally dependent on your fiberglass working skills.

[56 3100]

not doing gaylords $$$$$. will try my skills cutting one.

[dsraven]

a pic would help so we know what you are dealing with, but, without that, I would say cut it down the middle, both ways if required to make it fit, then make a wooden stand the same size as the outside of the truck box, plus a little bit so you can add the thickness of new fiberglass to hold it all together and end up to be the correct size when done, so fit it all together so it is the right size. don't forget to keep a crown in the middle or however you want it to be for that so it sheds water but also has a truss effect for strength. tape it all on the stand or use screws sparingly or whatever you need to do to keep it on there sturdily. foil duct tape seems to work pretty well for this task and if you use that fold over one end so it is easily grabbed when it comes time to remove the tape. if you end up cutting the top into 4 pieces they can be overlapped on the frame, secured, then a saw can be used to cut both pieces at the same time so you get a really even cut, the pieces fit like a glove and will only leave the thickness of the saw blade as a space between the parts. once you have it fitting and looking like you want build another wooden frame on the outside and hot glue it or use something removeable to keep the fiberglass firmy attached to the outside frame. don't have any structure built under the joint areas as fiberglass will run through some and stick the structure to the project which will be hard to get apart later. wax paper from the kitchen can be an aid here if taped securely over the leak zones, fiberglass won't stick t0 it or try some foil tape but I'm not sure if the tape glue will simply disintegrate when the resin hits it. once it is firmly supported the original inner wooden structure can be removed revealing the inside of the fiberglasss structure that needs to be held together. now all the interior surfaces need to be sanded everywhere with something like 60 grit so new fiberglass will stick properly. I suppose this step could have been dome prior to any work being done as iot may be easier as a single unit. no shiny or unsanded spots can be left unsanded or the new resin wont stick properly to that part. you can build in some extra strengthening ribs at this point and some plastics retailers may sell fiberglass profiles that you can use to keep the overall weight down or you can use plywood as ribs, like an old fashioned home built boat would have been made. think about reinforced areas where you may want a hinge, latch or hydraulic gas strut to help keep the cover open later. you can use plywood here or aluminum or whatever you desire that will take a screw or fastener. the areas with ribs or the seamed areas can now be "stuck" to the project using fiberglass matt you cab buy on a roll, like drywall tape except it is fiberglass woven roving. remember these ribs don't need to be a solid structure, they can be hollow inside to keep the overall weight down, it will be the fiberglass that becomes the strength. even styrofoam may work as it is only a medium used to hold the fiberglass matting in a tubular cross section. you can use some foil tape on the outside where the joints are so the resin doesn't always run out the crack. use the unwaxxed fiberglass for this so you don't need to sand it between coats. a ribbed roller is good to get all the bubbles out. you can also buy a tub of fiberglass chop that is good to fill any voids so when the layer of fiberglass matt is placed overtop of everything it will be easy to roll all the bubbles out of that as well. remember that the resin is not the strength, it is the resin soaked mat that becomes the strength, don't go leaving a bunch of resin in an area because you think that will make a strong part, add some chop to the rrsin so it has strength built in. now you need some pieces of woven roving mat that will be cut to fit the entire inner surface and roll up the edges for a complete covering plus a bit past the edges so it can be trimmed later. plastics shops usually sell a mat that is woven roving on one side and chopped strand on the other side and come on a wide roll they sell by the foot or meter. it is a one shot deal and saves a lot of time giving you a nice thick smooth inner surface because the stranded part will be the part you see. when it is all like you want it on the inside, after the woven roving step is complete, you can lay down a layer or 2 of gelcoat to finish the inside off and if you buy the unwaxxes gelcoat you can do several layers with the final layer having wax added so it will come out non sticky as the final step. gelcoat can be sprayed on but you need a gun with a huge nozzle for this. it does work well but makes a bit of a mess and will also require proper breathing equipment and a ventilated area. ensure all the edges have been trimmed and any "fuzz" has been removed before doing the final gelcoat step as what you see here will be the final look, just a different color after you choose a gelcoat color. it doesn't need to be gelcaoted if you are ok with the raw fiberglass look, in which case you would add the wax to the final coat of resin.
when done the inside, the cover should be nice and strong so the outside structure can be removed, any resin that got out the seams can be trimmed off the outside part with a razer blade, sander or whatever and then the project can be placed on the original wooden structure so it can be right side up and the outside gelcoat can be repaired with fiberglass bodyfiller and then completely final sanded with something like 60 grit so the new gelcoat will stick well. this is where the spray gun will really make things look nice and also make the job go quickly in a complete coat with not stopping to refill a roller or brush or work super quick to keep a wet edge on the gelcoat. the gelcoat is going to end up really orange peely so an extra coat is usually desired so it can be sanded smooth and polished when done. again, use the unwaxxed gelcoat for the build up and then add the wax to the final coat so it will dry hard and be sandable.
check online for additives that can be put in for better flow of the gelcoat, wax for the final coat, gelcoat spray guns, etc
anyway, sorry for the long winded explanation. I did a regel of my daughters boat last year so I have been through the fiberglass procedure. the roller or brush thing kinda sucks for the final finish as it leaves a lot of texture, that is why I bought a gelcoat gun, it worked awesome. ensure you clean it out completely after each spray is done or the thing will be full of hard resin and be garbage.

I bought my gun here

https://www.thegelcoater.com/collect...sin-spray-guns

here is a page that has ideas for additives etc. I used a marine additive because the gelcoat is a porous material and I was doing the underside of a boat. the additive made the gelcoat flow really well and also lay out flatter. also get yourself a thickness gauge so you will know how thick your coats are. there is also reducers to help with flow and you will need lots of acetone to clean your gun between each batch or the old gelcoat will harden in the tip as you spray the secon mixed batch. thats if you go for the gelcoat spray gun. the one I bought looks like a regular HVLP gun but has huge tips to flow the correct amount of gel and give less orange peel profile. when done the orange peel is sanded down smooth, nearly, with like a 180 grit, then a wool polishing pad and some gelcoat cutting/polishing compound is used. it comes out smooth as a fiberglass shower or tub.

https://www.bottompaintstore.com/fib...581_13582.html

[56 3100]

thanks DSraven . lots of good info as always.i might cut it down to what i need and let one of the local fiberglass shops give a quote on it .

[dsraven]

the backside fiberglass part would be the easier part to do once you have it cut down to size. when you get that part done you could have a shop spray the gelcoat on the outside, I would think to have a shop fab the backside stuff, lay up the glass and get the thing to fit the box and THEN do the top side in gelcoat, buff it out etc, the cost would be prohibitive compared to buying one to fit or going with a bakflip or something like that.
-you could make a wooden frame from 2x6 or 2x4 about 1/2 inch bigger than the box perimeter so as to leave room for the glass layup material on each side. you could taper the top rails on the front and back to give you the shape of a roof, slightly tapered from the center out to the edges, thats why I mentioned the 2x6 part but really for the amount of taper a 2x4 would likely be lots left after making the taper cuts. that will shed water and give the truss strength effect to keep it from oil canning when done and sitting on the box
-lay the previously split down the middle (fore to aft) cover on there, only one side
-cut the cover so as to be seamed right at the peak of the "roof"
-now do the length cut so it also leaves a bit of room for the glass layup on each end
-now do the other side, same deal
-when done build a frame on the outside of the fitted cover but try to make relief cuts or whatever so where there is a seam the wood will not be touching the cover. either that or wrap the wood with wax paper so the resin won't stick to the frame
-use foil tape at the cuts/joints to help keep the parts assembled as a single piece
-now you can flip it over and remove the inside frame. maybe use a few screws through the cut areas to keep the thing together and not flexing. these will need to be removed prior to the glass layup
-get some help for lifting, test fit it on the box. do required trimming etc. if you like the look take it back off and maybe screw a couple of 2x4 legs onto the frame so it will make it easier to work on. try to make it level as the resin always tries to run to the low spot
-decide if you need to add stuff to screw hinges or strut supports to and get that done. some fiberglass body filler would work for glue to stick those parts on and also take up any voids
-now you gotta sand the whole underside part where the glass layups will be
-decide how you will reinforce the thing so it doesn't oil can, or maybe it already is. some styrofoam is light and you can use that to make high spots under the layup for strength, just do the layups over the styro
-anyway, just some thoughts on how I would do it.
-fiberglass is relatively easy to work with once you get started. the woven roving with the chop mat on one side is almost a single step thing and if you are ok with the raw look on the inside you likely could do it with waxxed resin and be done the underside pretty quickly, a single coat of resin. then once it is set and sturdy you could remove the frame and swap it for the other frame for the underside so you could get some legs under and be right side up. then do the seam repairs on the top side, short strand fiberglass body filler there. then take it to the glass shop for a spray of gelcoat
-when done, if the shop doesn't buff it smooth and glassy for you, you will need a circular variable speed buffer and a real wool pad. I used a product called aquabuff for compound and it worked really well to bring the gelcoat up to a high gloss. there is aquabuff 1000 for removing the sand scratches after sanding the orange peel off, then the aquabuff 2000 will bring it up to look smooth and shiny like a fiberglass boat would look. this stuff works awesome for bringing a dull boat back to looking new again
-you can research the different glass cloths and mats etc. glass chop for filling the voids where the roving doesn't wanna push down and into the corners (just mix a small container of resin and chop when you mix up the resin for the roving and have it handy. it will be like a paste you can stick a blob into a corner before the roving goes down there. it will fill the inside corner some so the roving will not get bubble under it), rollers for getting the bubbles out, etc etc.
-stop at the local boat hull repair shop and talk to a glass guy, he maybe does small jobs for a deal and you will be able to see his work at the same time.

[_Ogre]

The simple version....
Cut to fit. Firmly screw everything in place. Grind out 8" strip about half way through. Fiberglass back I'd use 3/4oz mat. Flip. Grind out about half way. Repair as needed. Sand, paint, mount.

[dsraven]

Haha, good post ogre. Less real estate taken up with useless words.

[mr48chev]

Originally Posted by _Ogre

The simple version....
Cut to fit. Firmly screw everything in place. Grind out 8" strip about half way through. Fiberglass back I'd use 3/4oz mat. Flip. Grind out about half way. Repair as needed. Sand, paint, mount.

THIS, The same way you repair or patch a boat or anything else that is fiberglass. I highly suggest wearing an old long sleeve shirt that you don't like well enough to keep and button the sleeves and then when you are done grinding toss the shirt in the trash can. A good respirator is a must too.

[56 3100]

all good info thanks everyone. long sleeves a must soo true.have good 3m resperator.

[_Ogre]

wussies. i typically did it in shorts and sandals
def on the respirators, N95 are as cheap as they'll ever be

[_Ogre]

Originally Posted by dsraven

Haha, good post ogre. Less real estate taken up with useless words.

this ogre isn't capable of reading that much with a nap or 2
plus the fastest i ever typed was 12 wpm