PB'ing new transom wood to boat

78 Thompson

Seaman
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Jun 2, 2017
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74
I've been reading and watching different threads and youtube videos and I'm not sure if I should use 1/4" chop strand fibers in my peanut butter for gluing the transom wood to the back of the boat.
It looked like Friscoboater used fibers in his PB for the transom. Not sure if todhunter did and the guy I bought my supplies from said not to, if I remember right.
So that is the question, Do I or Don't I? or doesn't it matter, would it be a stronger bond?
The guy I bought the supplies from made it sound like it would be harder to do or to do right, if I used fibers in the PB.
Thanks for the help!
 

78 Thompson

Seaman
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Jun 2, 2017
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Ok I think I found my answer, came across an old thread where Woodonglass describes how to make peanut butter and when and where he uses it.
Now I just have to figure out how much to mix up, to cover the hull and transom. looked like Frisco used around 3 quarts?
 

froggy1150

Master Chief Petty Officer
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Nov 3, 2017
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I did use some glass when I did mine. Practice doing it several times and have all clamps screws etc ready to go. Mine setup faster than expected and if I wasnt practiced and prepared it would have been a disaster
 

buxmj

Petty Officer 1st Class
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Jun 9, 2018
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Sorry that I am late to the poll, I used chopped strand in mine. The chopped strand really gives the resin the structural strength and ties it all together, resin alone can crack. I feel like I am still a newb but only time I have seen chopped strand not added is when someone makes a fairing compound with resin and cabosil only.
 

JASinIL2006

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Feb 10, 2012
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Not much strength in PB without the fibers; definitely use the chop strand.
 

76SeaRay

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Aug 24, 2017
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I used 1/4 inch chopped strand in all my peanut butter. A note on the mix quantity, too much at a time and you will have it setting up in your bucket due to the heat (based on personal experience while learning). As froggy says, practice a few times to get a feel for it first...
 

78 Thompson

Seaman
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Jun 2, 2017
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Thanks guy’s
I will definitely get my clamping setup, and test before starting.
Maybe I should make 2 smaller batches then, I have heard about it getting hot in the bucket. Looked like friscoboater did it in one big bucket, guess if you get it spread out quickly maybe. But probably better to be on the safe side. Better to have extra time.
 

todhunter

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Sep 15, 2020
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Thanks guy’s
I will definitely get my clamping setup, and test before starting.
Maybe I should make 2 smaller batches then, I have heard about it getting hot in the bucket. Looked like friscoboater did it in one big bucket, guess if you get it spread out quickly maybe. But probably better to be on the safe side. Better to have extra time.
Yeah, mix it on the slow side (I think I catalyzed to 0.75%) and if at all possible, have a helper mix smaller batches on a table outside of the boat and hand them in to you. I showed my wife how to mix up PB and we were doing something around 20 oz batches. I can't recall how many we made...maybe 4-5? I think we had the transom set and clamped in maybe 40 minutes, and the resin didn't start kicking for another 30.
 

JASinIL2006

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Things you can do to get the transom in before the PB kicks:
- have a helper (this is essential, I think)
- use a bit less catalyst as @todhunter suggests
- refrigerate your resin before mixing in the catalyst
- do several dry runs before attempting to install the transom with PB
- make sure you have plenty of PB when you start, so you don't have to stop to mix some more
 
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