Best adhesive for balsa skin to ribs

Discussion in 'Construction' started by Devasen, Feb 5, 2021.

  1. Devasen

    Devasen Member

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    Guys, what adhesive are you using to get the balsa hull sheets to stick to the ribs when skinning? Is there a technique where you just glue a rib at a time and let each set before moving to the next? I'm curious how you get your balsa sheets to not want to straighten out when gluing and ruining the lovely curves of the hull profile?
     
  2. Beaver

    Beaver 2020 Rookie of the Year Admiral (Supporter)

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    Contact cement. Cut your balsa panel to shape, coat the backside with contact cement and let dry, coat ribs and top/bottom of the hull and let dry too. Once they're both dry to the touch (10-15min) carefully position the balsa where you want it to go and press it on. Done.
    Just make sure you line it up right the first time because once you make contact it's really hard to remove or adjust. ;)
     
  3. Bob

    Bob Well-Known Member

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    There’s actually a lot to sheeting to get a skin that takes nice holes.
    Good soft balsa. There are a couple tricks to selecting good balsa. Two layers of silkspan inside that are cross grained. I have started to use gorilla tape on my ribs and glue the sheeting to that. Makes unsheeting very easy. But you need a clean hull.
     
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  4. Kevin P.

    Kevin P. Well-Known Member

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    I’m giving the duct tape a shot, Fingers crossed that my sides don’t fall off in Georgia
     
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  5. Devasen

    Devasen Member

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    So something like this https://www.homedepot.com/p/DAP-Weldwood-3-fl-oz-Original-Contact-Cement-00107/100195615? Also are talking about putting the cement over all the balsa sheet, or just where it contacts the ribs? Thanks guys
     
  6. bsgkid117

    bsgkid117 Well-Known Member

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    I paint the ribs/subdeck/hull where they would contact the balsa sheet, and paint the entire backside of the silkspanned balsa with contact cement. I'm not the most precise person, knowing me I'd paint where the ribs should be on the balsa and I'd be off by 1/2" and the balsa would fall off in the lake.
     
  7. Devasen

    Devasen Member

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    Does the cement effect the penatrability of the balsa sheet much?
     
  8. bsgkid117

    bsgkid117 Well-Known Member

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    If you go crazy loading it up, it could. But a nice light coating, just enough to make sure you've covered it all, and you should be fine. I've passed drop test fine every time I've had to.
     
  9. Devasen

    Devasen Member

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    Good to know. I was afraid if I got too much,it might turn into self-sealing balsa:laugh:
     
  10. Bob

    Bob Well-Known Member

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    Last year I put the tape on for Wades in March. Ended up getting canceled. The tape was on for 5-6 sorties in MN and all of Nats. Then it made it through the Ice Breaker. I pulled the sheeting off but left the tape on for Wades in the fall. I don’t think the tape to the hull is an issue. If anything it would be the sheeting to the tape that could fall off. But it didn’t.
     
  11. Kotori87

    Kotori87 Well-Known Member

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    I tried out the duct tape method for attaching balsa during my winter resheet. I didn't notice any more sheeting issues than normal so I promptly forgot about the duct tape. Since then, both predreads have gotten absolutely shredded. SMS Schleswig-Holstein in particular got her starboard bow demolished, plus several rams on the starboard midships section that refused to reseal neatly. With nats just a couple weeks away, I decided to replace the worst section of sheeting. I would have done the whole thing, but I didn't have enough balsa. I started cutting away the old balsa, and I was surprised at how cleanly it detached. With just ten minutes of work, the ship's side was stripped clean and ready for fresh tape and balsa. Compared to the many hours I spent over the winter scraping and sanding to remove old balsa and glue, this is a night-and-day difference.
    20210703_160529[1].jpg
    Since this photo was taken, it took me another five minutes to put fresh tape down, then only a short while longer to install the new balsa. I know it's not a complete resheet but that's still under an hour to replace almost 1/3 of the ship's sheeting. I would have replaced more if I'd had enough balsa. Whoever came up with this duct tape sheeting idea was brilliant. I will never sheet another ship without a duct tape layer underneath to protect the ribs. Anyway, painting tomorrow and then its time to reassemble everything and give her the old bench test.