Skinning Compound Curves...

[oldlugs]

Hey folks, can any of you offer suggestions of easy ways to skin compound curves...? I'm finding it very tough to get 1/16" plywood to lay down on some sport 21 sponson tops... What's the hot tip? Thinner ply? Special clamps...?

Thanks, Duane

 

[SayMikey]

Hey folks, can any of you offer suggestions of easy ways to skin compound curves...? I'm finding it very tough to get 1/16" plywood to lay down on some sport 21 sponson tops... What's the hot tip? Thinner ply? Special clamps...?
Thanks, Duane

im building a Blazer sport 20 and used some clamps from Lowes, i use thin quick set to glue it all in place then come back with west systems. Its a pain been 20 years since my last wood kit but looks cool done

 

[oldlugs]

Hmmm... Maybe the formers just need more sanding so the high spots aren't so pronounced. Maybe I'll try 1/32" ply... I've got one of the Whiplash sport 21 kits to do as well, and somehow, I think it'll go more easily than the RHT one I'm working on now. I've got a bunch of Irwin HandiClamps, but I still can't get it all clamped up the way I'd like.

It's been about 17 years for me, since my last wooden boat... I guess I just need more practice.

Duane

 

[Roxyflash]

Clamps ,tape, weights what ever it takes.On the whiplash i build the gas versions what i do is i use ultimate glue i cote the under sides of the sheeting with it then glue the formers and stringers with it.Lay it on clamp what i can good tape works good then weights.The glue expands fills any voids.Never had any issues with it.Hit bouys at 60 mph fipped never pulled apart.

 

[SCOTT WITHERELL]

Ive been steaming the 1/16th plywood skins for years and bending it around a large coffee mug, try on a piece of 1/16th scrap 1st for practice,dont bend to far or wood will crack or worse break. steam in same spot on both sides (I get the wood hot) bend a little on mug and hold till it cools, steam 1inch forword of last spot bend a little so on and so on till it conforms to the curve of the sponson , if its bent to far (worped/ over curve) the plywood now is more maluable and can be bend back and forth alittle by hand with out steaming, "go slow",and be patient and this will make it easyer to skin the bottom of the sponsons.

 

[ZIonOB75]

Ive been steaming the 1/16th plywood skins for years and bending it around a large coffee mug, try on a piece of 1/16th scrap 1st for practice,dont bend to far or wood will crack or worse break. steam in same spot on both sides (I get the wood hot) bend a little on mug and hold till it cools, steam 1inch forword of last spot bend a little so on and so on till it conforms to the curve of the sponson , if its bent to far (worped/ over curve) the plywood now is more maluable and can be bend back and forth alittle by hand with out steaming, "go slow",and be patient and this will make it easyer to skin the bottom of the sponsons.

very nice trick.....

when dealing with curve i used to spot CA glue one at a time, start in a more straight part towards the curvy part while movin' i spot CA glue just enough to hold in place then seal with epoxy...it's more easier if the skin is wider than the frame, trimming to fit after glueing.

 

[namba276]

Duane, The sponson bulkheads are a little high on that kit. keep sanding. they will lay down when it's been sanded enough. Use a hard rubber sanding block and sand at an angle while slightly rotating the block. you will get it.That is by far the most challenging part of that little boat. good luck. Bob Tuttle

 

[oldlugs]

Thanks, Bob. It's gone together really well, so far. It's just those sponson decks giving trouble. :blink:

I remember the high school wood shop teacher always telling me, "MORE SANDING!"... :lol: BTW- I did get the balsa blocks well fitted & epoxied into the sponson wings, and they sure did stiffen up the hull.

Thanks also, Scott! That "steam it" answer was the hot tip. After I get the sponson bulkheads sanded down, I think the steam-rolled decks will just drop into place.

Cheers, Duane

 

[SCOTT WITHERELL]

my profile of newbe is just for international waters, but im far from newbe(for building that is),check out my sport 20,

 

[Mike Hughes]

For the weights, I use lead shot in 5 pound sandwhich baggies. I have 50 pounds worth for doing scales. You can put the wieght right where you need it and conforms to anything. I suggest if you are going to use sandwhich baggies you should double bag them. Otherwise you will end up with shot all over the shop if you spring a leak. I have heavy mil bags for mine. I also sheet decks with 1/32 ply. Then I do a 2oz fiberglass overlay which stiffens it up and adds strength.

Mike

 

[SCOTT WITHERELL]

For the weights, I use lead shot in 5 pound sandwhich baggies. I have 50 pounds worth for doing scales. You can put the wieght right where you need it and conforms to anything. I suggest if you are going to use sandwhich baggies you should double bag them. Otherwise you will end up with shot all over the shop if you spring a leak. I have heavy mil bags for mine. I also sheet decks with 1/32 ply. Then I do a 2oz fiberglass overlay which stiffens it up and adds strength. Mike

Mike : I used 1/32 sheetings for the decks , but didn't use 2oz cloth, thats probly why I see the frame ribs after it was in the water for the 1st time .next time ill use 2oz cloth.

 

[oldlugs]

"I plan to give out "5" free plans "for just International Waters people....

Hey Scott, sign me up!

Duane

 

[SCOTT WITHERELL]

"I plan to give out "5" free plans "for just International Waters people....

Hey Scott, sign me up!

Duane

 

[SCOTT WITHERELL]

"I plan to give out "5" free plans "for just International Waters people....

Hey Scott, sign me up!

Duane

Duane your already sighned up.,,,Member #2,646

 

[myrcbud]

keelhulled, I've been after a set of those plans for ever. When are the comin out?