Formula 27PC Transom Work

[Woodonglass]

Guess I'm missing something with your last comment. What is the reason to use a longer new piece compared to a short piece?

Cutting away more of the stringer, IMHO, would allow you more room when it comes time to apply the full layers of glass and resin to the transom and tabbing to the bottom of the hull, as well as making your stringer repairs a bit more easy. If you feel you have the room required then you're good to go. In regards to your last post, If you're using Polyester resin, it's mandatory to use CSM with it since the resin alone has no binders and once cured will easily crack and allow water to penetrate into the wood. The styrene in the Polyester resin breaks down the fibers in the CSM and uses them as the binder to blend everything into one homologous unit. Epoxy on the other hand does contain binders in the resin and can be used on a stand alone basis.

 

[alldodge]

OK thanks I got it.

I'm not using Polyester, I'm using Vinyl Ester resin, would it be the same for it?

 

[tpenfield]

I like the idea of wrapping with CSM but wouldn't a good coat or resin also seal the wood? Thinking or resin coat everything before assembly.

I believe water go in from all the screws which held the batteries and such caused the build up over time. Will make sure to seal all the screw holes this time

A significant problem that I have found with the wood/glass/foam structure in boats is that sometimes (perhaps often) the cavities that are intended to be foam filled, end up having some amount of voids in them, either through under filling or trapped air pockets. Along with the air pockets comes the moisture and then any exposed wood on the underside of panels, etc acts like a sponge.

Resin coating will certainly help, so you may want to go that route considering the amount of wood going back into the boat. The bulkhead . . . I would wrap that in glass (CSM) as that will act like grand central station for moisture, so it is worth the additional protection. IMO

 

[alldodge]

A significant problem that I have found with the wood/glass/foam structure in boats is that sometimes (perhaps often) the cavities that are intended to be foam filled, end up having some amount of voids in them, either through under filling or trapped air pockets. Along with the air pockets comes the moisture and then any exposed wood on the underside of panels, etc acts like a sponge.

Resin coating will certainly help, so you may want to go that route considering the amount of wood going back into the boat. The bulkhead . . . I would wrap that in glass (CSM) as that will act like grand central station for moisture, so it is worth the additional protection. IMO

Sounds like a good plan, I'll go that route. Only reason I'm hesitating on doing the smaller pieces is because they are small (6 inch wide and less). Also everything is fitting good so the more I put on them the less space I have to fasten. May have to sand some more off to have more room to add CSM and resin.

Looks like this week will be shot for doing much else. Easter weekend with the Mom's and then rain all next week

 

[Woodonglass]

Yup, VE and Poly are pretty much the same cept VE is stronger among other things

 

[alldodge]

Starting the glass side and opened my cloth, one is heavy CSM, figure 2oz like I ordered. The other is 1708 but looks pretty thick, I thought it would be a thinner cloth, something like material

 

[tpenfield]

Sounds right . . . The 1708 will be more like a thin blanket versus a cloth. It is stitched together with a CSM backing, which is the side that goes 'down'.

 

[alldodge]

Yep that's what I have, starting with 4 gallons of resin, might need some more.
Glass Dave on OS said I should use 1708 between the 3/r plywood layers, then one on the top. Used some cabosil and CSM yesterday to fill in some voids in the transom. Will use a bunch more when the transom wood goes in

 

[Arawak]

Yep that's what I have, starting with 4 gallons of resin, might need some more.
Glass Dave on OS said I should use 1708 between the 3/r plywood layers

Unnecessary. and adds a complication. You need to have CSM against the dry side, and you have two dry sides. So if you do this, you'd need to have two layers of 1708 with the mat sides facing out. Or one layer plus a layer of plain CSM.

 

[alldodge]

Unnecessary. and adds a complication. You need to have CSM against the dry side, and you have two dry sides. So if you do this, you'd need to have two layers of 1708 with the mat sides facing out. Or one layer plus a layer of plain CSM.

Sorry Arawak, I mis-spoke. Dave said to use CSM between the two 3/4 layers. Don't know why I didn't get notified you posted, go figure, glad we used CSM.

Been doing a lot of glassing over the last few days. Installed the transom and bolted it up

Put plastic wrap on the boards and was glad we did, had some drips which would have glued them


Installed the forward stringers and engine bulkhead. Glassed the first layer, plan to go back and add a higher layer and more resin.



Installed the first layer of 1708 and appears we didn't get some areas wet enough. Used caposil (not real think) and coated the transom wood we thought real heavy. Then laid the 1708 and applied more resin and used both the small and large air bubble roller. In some areas no matter how much more resin we applied, it still would not turn clear.

 

[tpenfield]

Looks like you are making some good progress. :thumb:

 

[Woodonglass]

Is there anyway the fabric could have become contaminated?

 

[tpenfield]

It could have been the cabosil (not sure why you would have used it for a lamination layer). Did the light colored areas seem like air pockets as you tried to roll them out? or was it more like liquid?

 

[alldodge]

Is there anyway the fabric could have become contaminated?

Anything is possible but don't think so. Used acetone on everything before we started and the wood had a thin coat of resin which had setup from the day before.

It could have been the cabosil (not sure why you would have used it for a lamination layer). Did the light colored areas seem like air pockets as you tried to roll them out? or was it more like liquid?

We used some cabosil to thicken the resin (just a little) so it would not run off as fast as we put it on. We used a brush to put as much on the wood as possible then lay the 1708 and a lot more resin. No matter how much we put on it seamed to not soak in. I used my finger in one area and pushed hard rubbing it, after a bit only a slightly bit of change.

May try something like you did by laying the 1708 down on a plastic sheet and wet it down, at the same time wetting the surface in the bot, then put the two together. Don't really want to do it this way but why was it not wetting through?

 

[tpenfield]

Yea, maybe check the remaining material that you have for any defects or contamination

 

[alldodge]

Looks like we did this to ourselves by adding caposil to the mix. I ground everything back off (what a mess again) and will wet the area, then lay the cloth and use a roller this time and no caposil. Once it starts to set and get sticky will do another layer. Will try to get three in tomorrow

 

[alldodge]

Have three layers on the transom and started putting the stringers in and coated them with the first layer.
Installed the water and fuel tank, and have been cutting wood for the deck. In the next couple hope to be pouring foam in. After that, finish up on the transom and stringers then paint and get ready for the motor

 

[tpenfield]

Nice to see that the work is coming along. . .

I don't recall if your tank was strapped down or just held by the plywood and dabs of foam over it. . . However, you will want to hold the tank down with something substantial while you pour foam in along the sides and to the underneath portion of the tank. Otherwise the tank will lift up with great force as the foam is expanding and starting to cure.

 

[alldodge]

It's not strapped, just has the deck holding it over the top. Haven't quit figured out how to apply enough weight to keep it down but still thinking about it

 

[tpenfield]

You could fasten some "L" brackets to the stringers temporarily or go across the tank in a few places with a 1" piece of wood and tie them into the stringers. IMO, that would be better than trying to estimate the amount of weight needed to keep it in place.

You definitely do not want a 'do over' on the foaming.

Also, are there neoprene pads under the tank, along the ribs of the hull?