Peanut butter recipe??

Crownline185

Cadet
Joined
Mar 13, 2010
Messages
7
I've read several posts referring to peanut butter for a transition from the stringers to the hull once bedded. Is this to make it easier to tab the stringers? Can you use pl if the gaps aren't huge? Also what exactly is used to make this peanut butter or should I just use jif extra crunchy j/k. Thanks for any advice.
 

Downwindtracker2

Petty Officer 2nd Class
Joined
Jun 25, 2008
Messages
110
Re: Peanut butter recipe??

If you are using epoxy, carb-o-sil,is a great thickner. Add mini-fibers and you have a fantastic gap filler.Don't breath the dust . It doesn't sand too well as it's pretty hard. It doesn't work as fairing.
 

drewpster

Commander
Joined
Oct 17, 2006
Messages
2,059
Re: Peanut butter recipe??

I dont recommend using PL to make fillets. Pl does not form very well and tends to bubble. Its ok to bed stringers with it, but I would use Peanut Butter to do fillets. (fill corners to make the glass lay in to them better)
Everybody has their own mix. Try this, you need resin, cabosil, chopped fibers, and glass bubbles or talc.

To start use just a small amount of resin until you get a feel for it, say 1/2 pint.
Have everything on hand ready to go. Go ahead and kick it with mekp. (some do this after the fillers are added, I prefer before, the mekp mixes better in plain resin)
First add the fibers. You need enough that it mixes in to the resin completly without thickening it at this point. It should perfuse through the liquid, but the liquid should still be loose and easy to stir.
Second add cabosil. Stir in and keep adding about two heaping table spoons at a time until the mix is the consistency of loose mayonaise. (adding the fibers first help disperse the dry cabosil)
Third add talc or glass bubbles. Keep adding until the mix thickens to loose peanut butter. It will be easier to handle and spread if it is slightly looser than actual peanut butter, but close.
Next, scoop the contents out in to a sandwich bag (the big ones). Cut a corner out of the bag and squirt a bead of your PB in to the corner. Form the fillets using a plastic spoon. In the morning, you got fillets.

OH! work fast, because the stuff will gel on you. Once you get a handle on it, you can mix and squirt in plenty of time. If it gels too quick, reduce the amount of MEKP.
The mix is the same for epoxy, with some adjustments, and a longer wait time.

enjoy
drewp
 

Crownline185

Cadet
Joined
Mar 13, 2010
Messages
7
Re: Peanut butter recipe??

Awesome, thanks so much for the detailed instructions. Does this add strength to the stringers along with making it easier to glass. Also the one stringer I cut has a gap of 1" for about a 3" section, don't know how I screwed that up but anyway think I should recut or would it be alright to cut a shim and bed it and attach to the stringer with pl?? Thanks again!!
 

erikgreen

Captain
Joined
Jan 8, 2007
Messages
3,105
Re: Peanut butter recipe??

For a gap that large I'd either recut or cut another piece of wood to fit and glue it to the stringer with epoxy.

My favorite peanut butter recipe is simply epoxy with wood flour... the stuff you buy, not just plain sawdust. It's cheap, relatively non toxic, and it thickens resin faster than anything else I've tried. It's strong on its own, but you can add milled or chopped fibers for strength if desired.

Plus due to the color it actually *looks* like peanut butter :)

Erik
 
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