78 22 FF Rebuild

[slippery73]

Thanks.  I had planned on using a propane heater until I started reading the warnings on the MSDS!!!!  I like the idea of the oil filled heater.  It was 50 degrees here for a little while today so I should be able to get the temp in the garage up to 60-65 on a day like that.  Only problem is everything has to line up just right with my helpers/temp/timing etc.  I have read that mixing is the most important part of getting this right.  I plan on using a 1/2 hp drill with a paint mixer for at least 3 minutes or so after I add the MEKP.  Does that sound cool?

I'd stick with the oil heater, thats the safest bet.  As far as mixers go you want a paddle mixer, not a regular paint mixer, like one of these :  http://www.amazon.com/Nattco-Paddle-Mixer/dp/B003XJ0Q7M  


You want to mix the material for a minute or two before you add catalyst, then while mixing, slowly have someone pour in the catalyst.  You'll see the catalyst float on top until it becomes mixed, continue mixing for several minutes.  The material will heat up once it starts to kick off, feel the side of the bucket occasionally, if its getting warm go ahead and pour. If not, its not going to hurt it to mix it a little longer.  You can do one bucket after the other, you won't have to try and mix them all at once. The material won't kick that fast where it will be an issue. One helper is all that is needed.

Make sure you make a funnel or form to pour the material into.  I made one by cutting two pieces of wood into a Y shape with a jigsaw, then screwing a piece of plywood across each side of the top of the Y. The bottom of the Y goes into the transom cavity and allows an easy pour.

Also, make sure there aren't any holes that the material can ooze out of. Keep some duct tape handy incase some pop up unexpectedly.

[Curious]

Thanks for all the advice, I really appreciate it.  This is obviously a one shot deal, so it helps to know I'm on the right track.  Couple more questions if you don't mind:

Nida-Core has a catalization guide that basically says I need 310 cc's of catalyst per 5 gallon pail at 65 degrees.  310x5gallons= 930 cc's or just under 32 ounces.  I purchased the catalyst seperately and I just want to make sure I have the right stuff- MEKP.  MEKP is MEKP with no variations, right?  I should follow their guide exactly, correct?

Nida-Core says that the working time before it starts to set up is 18-24 minutes.  Has that been your experience?  I assume longer if it is colder?

Regarding the holes- are smaller screw holes ok to tape with duct tape or should I bondo them first with a polyester based filler?  Planning on using pvc pipe with PVA release agent on them like bondobill did for the 1 1/4" scupper holes.

I'm planning to coat the two inner skins with polyester laminating resin and let that set up just prior to the pour.  I read about this being done (I think it was on classicmako) and it is said to really enhance the bond between the existing fiberglass inner skin and the Nida.  Thoughts?

[slvrlng]

There are different concentrations of MEKP so you need to find out which one 3M is using to get those results. You also need to find out the concentration on what you bought. Most MEKP is a 2.5% concentration, but you need to know which one you have. It will still work but you might have to back off on amount used otherwise it could set up really fast if its a higher concentration. Also see if you can find out a minimum amount you can add from 3M. If you back off to that level it will still set up but give you more working time. The hard part about coating the skins is figuring out when it has set enough that you get adhesion but not too much and you lose all adhesion.

If there is a hole this stuff will find it and ooze out. The main problem I have seen when people pour transoms is they don't support the skins enough and end up with a bulge, so make sure it will not flex. Slip gives great advice so if you follow what he says you should have no problems. Good luck!!!!

[Curious]

Thanks for the reply.  Is this stuff supposed to come with catalyst or is it typical to purchase separately?  The Nida website says "catalyze with MEKP".  The Arjay site (I'm told it is all the same stuff made by 3M.  As a matter of fact, the product I have doesn't ID Nida or Arjay, just 3M) identifies the catalyst as Lupersol DDM-9 (MEKP).  I assume that it is the same?  Nida has a pretty good tech dept. so I can always email them with questions.  

It would be a lot easier if they provided a set of instructions with some of these details, maybe I'll see if they have that available.

With regard to the laminating resin-  I was under the impression that it never really sets up (no wax) so it stays tacky and that's what helps enhance the bond.  But I'm pretty new at this so any info is much appreciated.

[slippery73]

Thanks for the reply.  Is this stuff supposed to come with catalyst or is it typical to purchase separately?  The Nida website says "catalyze with MEKP".  The Arjay site (I'm told it is all the same stuff made by 3M.  As a matter of fact, the product I have doesn't ID Nida or Arjay, just 3M) identifies the catalyst as Lupersol DDM-9 (MEKP).  I assume that it is the same?  Nida has a pretty good tech dept. so I can always email them with questions.  

It would be a lot easier if they provided a set of instructions with some of these details, maybe I'll see if they have that available.

With regard to the laminating resin-  I was under the impression that it never really sets up (no wax) so it stays tacky and that's what helps enhance the bond.  But I'm pretty new at this so any info is much appreciated.

It doesn't come with catalyst.  There is an example of the catalyst needed below.

http://www.fgci.com/bp_viewproduct.aspx ... tem=132667


As far as adding laminating resin to the inside skin... seems kind of pointless to me. The transom pour material is made of polyester resin, it should achieve the same bond as regular resin. The only difference is your adding another layer of material in between the skin and the pour that can fail.  I'd keep my pour a straight pour.  You will want to clean out the inside skin as well as possible.  I'd try to wash it down with acetone really well.  

You don't need to worry about installing pvc pipes for holes, etc. Everything can be drilled after the pour is done. The stuff drills out really easy.

Last thing, point was made above that biggest issue is the pour bulging out the transom.  Awesome point.  You need to reinforce the back side of the boat really well so it doesn't flex out.  I have included a pic of the last boat I did a transom for.  This piece was bolted on the transom skin and not removed until after the pour.  A similar piece was on the inside of the boat as well.  (interior of boat was gutted and had no inner skin for our pour.)

[Curious]

My plan is to cut the pvc into 1 1/2" sections and insert them into the scupper holes so I don't have to worry about covering them over so the compound wont leak out.  Then I plan to use the holes to insert bolts with a 2x4 on edge on the outside and some L channel on the inside (due to space restrictions) in order to prevent the bulge issue.  There are three 1 1/4' scupper holes going across the transom (see second pic down at the beginning of this thread) where I'll do this then I'll do the same thing near the top but using the engine mount holes also with a 2x4 on edge.  Then on the lower engine mount bolts I plan on either inserting the bolts alone or maybe using a piece of plywood similar to your picture to help spread out the load.  Either way I'll snug it all up so the cavity is uniformly 1 1/2" all around.  I also plan on having plenty of clamps handy to clamp the top near the cap to further prevent the bulge there.  I probably didn't explain this right, but I've got it figured out in my head....  At any rate, thanks for the advice on the bulge issue, I am very cognizant of it after seeing at least one thread on here where it didn't go so well.

Maybe I'll just skip the laminating resin idea? Sounds like it might just complicate things.  I am currently in the process of roughing up the inner skins with 36 grit as recommended by the Nida tech guy I've been e-mailing. This is really looking good- nice and roughed up and clean.  Then I'll clean it really good with acetone when that's done as the final step before the pour.  

I'm still not clear on the MEKP issue and I couldn't open the link you posted.  Thanks again, I really appreciate the advice.  There really aren't a lot of people using this method in my area so I hope to start a new trend with a successful and bulletproof final result.  Cross you fingers and I'll keep you posted!

[Curious]

This is the catalyst I purchased:

http://www.carbon-fiber.us/mekp-hardene ... p-349.html

[Curious]

Finally poured the transom today.  Moved the boat over to my brother's (heated) garage and actually had outside temps around 50 degrees anyways.  Very successful pour.  I was prepared for all kinds of problems to pop up but really had nothing too chaotic happen.  I had a little leakage down around the transom drain area but it set up and stopped flowing so it was really a non-issue.  Same thing as I poured up the sides.  Even though I dammed it up with Gorilla Tape and PVA'd plywood strips, I still had to chase a couple of spots where it was trying to ooze out, but really very easy.  I'll let the photos do the talking:



















More pics to follow, photobucket just shut down on me.  Nida Core was very easy to mix and pour, found its own level, tapped outside with a rubber mallet to release air bubbles then let it harden a little before pouring up the sides.  Took a while but finally kicked off and peaked out at around 170 degrees.  It cooled down and is like concrete.  I'll pull the plywood off tomorrow, take more pics and let you know how it looks.

[Aswaff400]

looks good, you can come to my transom too when ever you like

[gran398]

What a deluxe job, know you have a well-deserved sense of accomplishment.

The prep is impressive. the pics say it all, especially the interior shot pre-pour. The very bottom next to the hull looked perfect.

Congrats

[Curious]

Just peeled off the plywood dams, pulled all the tape and popped my pvc spacers out of the scupper holes.  Nida core is like concrete everywhere.  You can look into the scupper holes and see fiberglass skin/nida core/fiberglass skin.  Appear to be a solid, seamless bond between the nida and the fiberglass.  I'm very impressed and yes, gran, feeling a sense of accomplishment (and relief!).  More pics to follow.

[Curious]

Quick question without going into too much detail-  My brother is going to do the recap and has a pretty good handle on how to do it and what to use but just to be sure we're on the right track, what is the correct material to use to recap?  Woven roving? Biaxial?  Mat?  What works best for wrapping around the corners?
Thanks, Dan

[Curious]

Here's a few more pics.  By the way, I ended up using 12 gallons total of the Nida Core.













You can see on the port side where it started to ooze out from under my plywood and Gorilla Tape dams and kind of built up a little on the top of the rest of the pour.  Still not a big deal.  Just got everything level and drew a line to grind down to as a starting point for the glass work.  Again, I would have prefered to pour a solid transom up to the gunnel height and add a bracket but financially it just isn't going to happen right now so I'm pretty much bringing everthing back to original.

You can also see where I removed the PVC spacers from the scupper holes- solid as concrete and appears to be a seamless bond between fiberglass outer skin/Nida/fiberglass inner skin.  Oh and I decided to pour the motor cut out to the top of the plywood with the intention of cutting it out afterwards.  I just PVA'd the plywood and cut out the hardened Nida afterwards with a jig saw.  I took my time but it was pretty easy to cut.  Now I have a big chunk of the stuff to play around with.  I've done everything to try to break it but so far it's not happening.  I'm pretty psyched with the results.

[SeaOx23]

Looking good, cappy!

[Curious]

Thanks, SeaOx.  You should see it now!  Glass work is under way and looking really good.  I'll try to get some pics by tomorrow.