View Full Version : Strengthening Balsa Wood/ smoothing lines
Chrisjhusker
07-01-2002, 09:15 PM
I'm using 1/16" balsa wood for the front half of my 48" Deep V. It's too flimsy on it's own, so does anyone have a suggestion on how to strengthen the wood to keep it from cracking under stress? Also, anyone know of anything similar to Bondo for cars that I can use to smooth the lines on the balsa wood without adding too much weight?
RickE
07-01-2002, 09:35 PM
You could coat the balsa with a layer of 30-minute epoxy resin that's been thinned 20-30% with denatured alcohol. This will strengthen the sheeting, as would adding a layer of fiberglass cloth/resin to the surface as well. The thinned epoxy trick will also fill the grain in the wood without adding much weight to the hull. As for actual filler compound, small dips and the like can be filled with regular wall spackling compound, sanded smooth and again covered with epoxy or even just primer paint if you find it strong enough.
Hope this helps,
RickE
Chrisjhusker
07-02-2002, 09:06 AM
Would that mixture of epoxy resin be 70% epoxy, 30% alchohol, or 70% alchohol, 30% resin?
RickE
07-02-2002, 12:34 PM
70% two-part epoxy resin, 30% denatured alcohol.
RickE
ascothouse
02-04-2005, 06:12 AM
I'm using 1/16" balsa wood for the front half of my 48" Deep V. It's too flimsy on it's own, so does anyone have a suggestion on how to strengthen the wood to keep it from cracking under stress? Also, anyone know of anything similar to Bondo for cars that I can use to smooth the lines on the balsa wood without adding too much weight?
Hi Chris
I may have the answer to your problem. I have been developing a method of strengthing balsa wood using a combination of superglue and one of our new products ink jet transfer vynl. If you send me your address I shall post a kit out to you for trial.
Thanks
Russell
R1DER
02-04-2005, 08:08 AM
Can't you double up on the Balsa ? or use thicker ? be alot less hassle.
R1DER,
About the 'filler'. 'Bondo' works, so does 'Plastic Wood' or any of the other fillers used in wood working. How about coating with epoxy, then covering with one of the aircraft 'skins', like 'Coverite'? The 'trick' with fillers is to cover to excess, then do LOTS of sanding - lol ! Then water proof it with something (more sanding)...
- 'Doc
Hydro Junkie
02-04-2005, 01:06 PM
One thing nobody mentioned for a filler is epoxy mixed with micro balloons. It's waterproof, easy to sand, and can be used to strengthen the hull at the same time IN ONE STEP. Just coat with the mixture, sand and paint.
Fluid
02-04-2005, 03:17 PM
None of these suggestions, with the exception of thicker wood, addresses the real problem - insufficient material strength for a boat of that size. Even hardening the balsa will not give it enough strength to withstand much in the way of rough water, particularly if the boat is gas powered (vibration). Even if electric powered, the sheeting will flex and have very poor perforation resistance. :(
If the boat is already sheeted, then the best response is to use fiberglass. The easiest way is to use 3/4 ounce cloth and stick it down with CA, then fill the weave with thinned epoxy. The strength afforded by this technique is not as good as with heavier cloth, but it is easier to do and is far better than thin, weak topical coatings of glue. :p
Model Magic is a great product to smooth sheeting in applications like this; it is very similar to drywall spackle but lighter. Not cheap, but sands real easy. Needs to be waterproofed afterwards - primer and paint does that. ;)
If not already sheeted, use a minimum of 1/16" plywood! Glass is still not a bad idea..... :D
CFRACR
02-05-2005, 07:06 AM
Fluid said what I was going to say, Good Job!!
Thats what I would do, except I use green model puddy to fill with. Easy to sand and leaves a nice smooth finish. But thats my preference, all of the suggestions will work for filling though.
Icman69
02-11-2005, 06:05 AM
I am part of the crowd that says epoxy and cloth for filling gaps there is a waterproof filler exactly like bondo, it called featherlite. I just finished building one of the ORCA boats from Balsa. After sanding the balsa smooth I coated it with epoxy and cloth any pits or low places after with feathrelite.
Here is a link to the place I buy all of my building supplies. I build hulls for one of the web sites and this is some of the best prices I have found.
http://www.shopmaninc.com/
Enjoy.