How To: Bob an Early Model 4Runner Top

[CTENG in KS]

Now in terms of strength, a fiber based composite is always strongest when the fibers are in tension.  I am using the cloth glass for just this reason: you can control the directional strength of the layup.  What I mean by this is that you can position different layers of the glass at different angles to ensure that different loading scenarios will all load the glass fibers axially instead if using the resin matrix for strength.  To do This I am using a std 45-90 degree layup.  Alternating layers of the weave positioned horizontal/verticle the 45/-45..see pic:

[CTENG in KS]

Once I got the area tidied up I needed a clean surface to work...enter plastic bag, and you will want some cardboard to mix your resin on.  Start by cutting strips of glass approx. the length of the v-notch on the side you want to start on.  Bout 25 inches.  You want them to start out thin and get sequentially thicker.  Cut a bunch.  You will need WAY more layers than you expect.  Always happens.  After you cut out a bunch of strips then cut a few more and slice them into squares.

[CTENG in KS]

Now time to mix up some resin.  If you can find it, use epoxy resin.  It tends to resist delamination from water much better, however the stuff at the autopart stores is mostly all polyester resin.  This will work fine too, just make sure to paint over it befroe you go out in the rain.
The resin will be in a large container...looks like goop, smells awesome (I think) with a wee tiny tube of hardener.  The hardener is powerfull stuff, it don't take a lot.  For gods sake make sure you have lots of gloves on hand.  The most important part of fiberglass work is patience.  If you try to rush you will end up with resin all over your gloves, then your brush handle...pretty soon you have a mess and it takes you longer than if you just took your time in the first place.  If you get resin on your gloves, ditch them and grab a new pair.
First I threw a single layer of glass on the inside just to act as a buffer, you don't really need to its up to you.

[CTENG in KS]

Now...step the first:  Make sure you still have everything lined up where you want it and make sure your surface is nice and clean.  Wipe it down with ethyl alcohol or even some fantastic if thats all you have, just get all the dust off.
Then you want to lay down a layer of resin on both sides of the joint.  Start by laying a first strip along the joint (make sure you use one that is wide enough to span the entire joint if you have gaps) and use the paintbrush to smooth it down and make sure it is fully covered with resin.  You want to push the resin into the cloth to make sure it fully soaks in.
Then grab your first set of squares and start laying them so they look like diamonds and the fibers ar in the -45/45 configuration.

[CTENG in KS]

You want to keep alternating the cloth positioning as you build up the layers.

[CTENG in KS]

Ths is where I ended for lunch...just about done on this side.  If you end up a little low you can always use some body filler, etc, just like on metal to get everything nice and smooth.

[*** YELLER ***]

Thats some purdy work bubba, if all goes well I should have an 86 SR5 next week.

[CTENG in KS]

Went back out after a nice rest watching Idiocracy to hit the other side.  May need to add a couple more layers, but it was getting too cool and the resin was thickening on me making it hard to werk with.
First pic is the dr side, already set up prety well.
Also a look at the psuedoprofile.

[Wermz84]

   Awsome job so far!  thanks for explaining it all.

[Rainer]

Same as werms, it looks good, good directions.

Mark

[CTENG in KS]

Tomorrow I gotta do the top...there is a bit of  gap so it is gonna be tricky...

[Z0RACK25]

Wow, that looks bad man! Thanks for all the great info on working with fiberglass! I don't think I'll be doing anything that radical to my Runner for a long time, I need the extra space in the back for camping gear  heh.

[*** YELLER ***]

great instructions, thanks for makin it easy for all of to follow along   

[CTENG in KS]

Time to eat so I will update first.  The top has been a pain. There is a gap and I decided not to trim more to get rid of the gap because I don't want to lose any more space behind the rear seats...I have plans for that area.  I decided to utilize some of that fiberglass mat I mentioned earlier.  Since it is stiffer that the cloth weave I figured I could make a bridge then build on that.  I cut a length just wide enough to span the gap and used resin to attach it JUST at the edges where it meets the top.  Then I gave it a little time to start setting up so it would hold while I worked ontop of it.

[CTENG in KS]

While that was setting up I added a few more layers to the passenger side which was a little low, then decided the top near the corner was not building up very fast at all.  I decided to use some of the mat as filler.  I already have PLENTY of strength in the cloth layers...prob about 25 ply at this point.  As you can see it is no where near as neat and clean as the woven stuff.

[CTENG in KS]

Since there is so much volume I need to fill on top I went ahead and added a third layer to my process.  I stated out with a layer of -45/45 squares (these were easier to use for the first layer) then a layer of -90/90 cloth, then I threw in a layer of the glass mat jsut to help speed things along.  Here is where I stopped, I am gonna go back this evening ans build it up all the way.

[BLACKDOG]

  good pics,  good explanation, awesome work!

My dad and I tried to do some 'glass work one time, got a "how to" book, and went to town.  couldn't make heads or tails of it  

Your process and the explanation of is great  

[Redbeard3261]

I did the top on my old 87 by removing the front glass of the sliders and shortening 13 inches to refix the front track to make 1 solid glass

[DTB]

I did the top on my old 87 by removing the front glass of the sliders and shortening 13 inches to refix the front track to make 1 solid glass

pics please

[CTENG in KS]

I did the top on my old 87 by removing the front glass of the sliders and shortening 13 inches to refix the front track to make 1 solid glass

Yeah, I thought about that but I really wanted to keep the sliders in there.  This werks exactly how I want so I am happy. 

I finished glassing the top panel so maybe tomorrow if I have time I can pull it out of the garage and snap a couple pics of the big picture.

[Wermz84]

Dang mang, you are making excellent progress!

[NC854Runner]

Great job I plan on doing the same thing to my 4runner. I found 2 tops for $125 so I'm planning on make me some extra tops to. The one on there now I'll keep for the winter, second one i plan on fixing it just like you did but where the two parts come together i was planning on using latches from a jeep hood to pull the two together with a rubber seal between them. I'll let you know how it turns out yours is looking good. The last top i was planing to make a bikini top out of it.

[MT4Runner]

A bit more advice:

Nice work cutting over the pickup....I cut mine off the Runner and on sawhorses...a little easier to access.

I like to use the wider strips on the bottom, narrower strips on top.  When you sand and fair it out, then you're not cutting into the longest fiber strands of your widest strips.  Mask everything.  You will save a lot of cleanup if you had masked off the window molding.

Where you floated the mat across the gap in the top--nice work--but not for novices.  If any of you copy this, stick a piece of 2" wide masking tape underneath the gap, and it will support your glass and catch drips.

Mix the resin in an old yogurt cup instead of on cardboard--lots easier to contain and mix, and easier to hold while you're applying.

Use a small squeegee (cut from the side of another yogurt cup) instead of a brush--so you don't end up "resin-heavy".  Resin has relatively no strength next to glass fibers...if anything, you want your thickness to be mostly glass.

Plastic grocery bags don't stick to resin.  Use them for masking.   You can also do "poor man's vacuum bagging" by pressing a sheet of plastic over the wet glass/resin...you can smooth things out while keeping your hands dry on the other side of the plastic--and it saves a lot of sanding and grinding later of all the stray "hairs" that stick up.

[CTENG in KS]

I don't have much issue with stray hairs due to the cloth weave being pretty tight and clean.
Using the bags to "vacuum bag" it is a good idea.
In terms of over impregnation with resin, I go very slowly with the brush and spend plenty of time pushing the resin into the weave.  This way I just use a small coat of resin and work it into the layup instead of just slathering it on the glass.

I didn't have anyplace to cut the top off the truck so I just used the truck like a big jig to keep everything lined up.

[MT4Runner]

I'm not knocking your work at all.  You do very nice glass work--but you make it look fairly easy.  Someone trying to copy you without any practice might get a little frustrated with "hair"...brushing resin into glass isn't awful, but it can benefit from a practiced touch.

Mine got cut in the same place, then I glassed in a piece of plywood and cut an aluminum topper window into it.

[CTENG in KS]

Ahh yeah, I saw yours on that pirate thread.  I was wondering how you did that.  Looks good.

[THK Matt]

this is an early attempt to a Hummer H2 SUT love it

[andrewmch]

Hey what did u all do with your quarter windows? Im in arkansas and i cant seem to find a right rear quarter window....  Im in bad need of one...  A guy at work. well i work as a painter and i had it parked near the street and a guy threw a rock at it with a weedeater and it shattered....  U guys still have one???

[CTENG in KS]

Sorry, I kept them for bout 6 months and then got rid of em.  COuldn't find anyone that wanted thenm and they were taking up space.

[bigarms23]

thanks for the explanation but i was wondering why cut the back instead of cutting the front and just drilling new holes just curious other than that it looks great