1969 Mustang Stringer Rebuild

Those beers are coming to the next reunion I make it to!

The lower cost of the mat is easily offset by the amount of resin it soaks up. Mat is great for building thickness quickly for impact resistance, etc.

Dont worry about getting tubes for thickened resin. We used ziplock bags. Get a LOT of cups. Get some stirrers too.

We are never short on beer

WakeSlayer wrote: Those tubes suck.

Noted.


So what's the verdict on the floor? Cloth on bottom, mat on top followed by cloth? Cloth on bottom mat only on top? Cloth on bottom and two layers of cloth on top?

Once I figure that out I'll add some buckets and cups and place my order. Can I just get some paper drinking cups for small amounts or do I need to order anything special from USC?

David,
A layer of cloth on both sides of the ply floor is fine. Just make sure you wrap the edges as well.

Is wrapping the edges just for abrasion resistance? Didn't do that to mine.

David,
Any wood that isn't real structural, a layer of cloth is fine as well.

Chris,
You're correct that wrapping the edges is to prevent water absorption. You should have zero abrasion since the floor ply is set in thickened epoxy bonding it completely to the tops of the stringers. At the edge that bumps the hull sides, it glassed there preventing any movement as well.

My plywood floor is CPESed, epoxied all over, cloth on both sides and more epoxy on all sides. The hull edge sides are bedded and fillet-ed with cabosil and then glassed to the hull. If water gets in there, its because the boat caught on fire, and I forgot to tell the firemen not to get the interior wet!

It's tha glass in a FRP hull that gives it the strength. The resin simply holds it together. Resin is relatively brittle and does crack when flexed without reinforcement. It's the reason wood boats "restored" with epoxy fail - the epory cracks, wter gets in and the wood rots from the inside.

The USC order has been placed    I think that was the hardest thing I have done so far.

In the meantime, I am working on my secondary I pulled over the weekend. Here's my plan, and let me know if it's a good or bad plan.

First I traced the old stringer and rough cut, leaving plenty of extra for scribing. Put it in the boat, making sure it is plumb. I have 3 2x4s cut exactly the same to use as spacers between that secondary and main. Next I will scribe the bottom on each side, remove from the boat and fine tune it with a jig saw and my new Harbor Freight power planer. I'll then set her back in the boat and fine tune some more if needed. Now I have to find the height off of the mains. Not 100% sure how I'll do that yet but I assume it will involve levels, calipers, etc. Once I figure that out, I'll rip her down and fine tune as needed with the planer. Then cpes and bed once the material gets here.

That sound about right?





Now questions.

The rear of my secondary was notched at the bottom. I would assume I need to notch the new one as well. And how tight do I want it to the transom? Do I need to scribe it in or will epoxy filling the gaps be close enough?





My measurements before I pulled that secondary revealed that it was not parallel to the main. I was going to make sure the new one was. Does anyone see a problem with that?

I'm also starting to think about drainage. Seems like there are two schools of thought around here, one is to drain everything to the bilge and the other is to only drain the exhaust cavities into the bilge and let everything else drain into one spot that can be accessed by some other means, or just sealed off completely.

I'm not sure how you could seal everything off completely. With this little boat and some of the rough water around here, there's always some wash making it's way into the boat. Do you run the floor all the way to the rear between the secondary and the hull like I have mocked up in the pic below?



Well thanks for all the help on the epoxy order. I feel like I am making some progress again.

If you can get that main more closely matched to the transom, you'd be better off. You can fill the gap with thickened epoxy, but thats a big gap and the orientation will be a real pain.

Im assuming those blocks are just there for bracing, right? I would put any ribs/supports vertical so they actually offer support between the hull and floor. Leave out any braces in the exhaust cavities, it makes it a real pain to route the exhaust hose. The later boats (1971+) didnt have any, unlike the earlier ones- so theyre definitely not necessary.

Personally, Im of the school of thought that says any way for water to get out is a potential intrusion point. I only drain from the exhaust cavities to the bilge, the rest I drain together and access with a hidden port. There is no way water *should* get under there, but if it does, I can still get it out. Thats not the way CC did it on the early-mid 60's non-foamed boats (they drained everything together), so thats certainly an option too. I have encountered one boat with a clogged drain (leaves) though, and a large cavity ended up holding water for an extended period of time... not pretty.

As far as where to end the floor, if you plan to keep the platform, then leaving access to the bolts/backing plates by ending the floor short of the transom isnt a bad idea. Diverting the water that might get into that cavity from the floor is one way to handle that. Or putting in a rib that blocks off the forward cavities (~12" from the transom) and draining those 2 rear pockets to the exhaust cavities (and bilge) would work too.

82Fineline, the regular mat that USC sells dissolves just fine in epoxy. I had a hard time telling the difference between it and the epoxy specific stuff I had used previously.

That exhaust port looks borderline. As long as you are in there...

Oh yes, definitely seal up the under bow area. CC fixed that mistake in their second generation of fiberglass boats. The amount of exposed foam in my sister's '69 blows my mind! You'll want to bring the floor all the way to the nose. Creating an "air box" (like the 71+ Mustangs and Skiers) will give you somewhere to mount the kick panel.

I put an access port in the front facing wall of the battery box on our BFN.

Thanks TRbenj, like I said Im not educated on epoxy yet and was worried.

Awesome looking mustang vondy, good luck with the build. Ill stop hijacking your thread now

WakeSlayer wrote: Jamestown just sent out an email with a 20% off CPES offer. Ain't going to get better than that. $179 for a 2gallon set.

They sent another one right before that for free shipping too. That does make it a deal.

I like the idea of a pvc threaded cap to get water out of the bow area. I put a 3/4" pvc pipe at the lowest point in my bulkhead behind the battery box with the pipe extending to just past the pylon in the bilge with a pvc cap that I can unscrew to see if any water is getting trapped in there.

Hay Vondy! go to the home depot and get a cheep power hand planer its the sh%t. check out my sep thread and look at the transom pics? thats the only way to do it. you will be amazed at how well it works. Jeff