Balsa core lamination

[Gmcviper]

I used rustoleum topside with grit for the floor.

[Hippie459MN]

I live near Cambridge. Rj my wife and I met you last fall on hydrostream run, we had the red and black viper with the tower of power.

Nice to see another Hydrostream in the neighborhood. Im only about 20 minutes from the Cambridge area. Just north of Saint Francis a little bit. Next spring/summer maybe we could hit up a few lakes. I have been itching to get my Vulture on the water and I am just about there.

[Aaronhl]

What type and weight of fiberglass should I put over a core?

[tunnels]

What type and weight of fiberglass should I put over a core?

Ok lets back peddle a little first !
what thickness is the core ? 3/8 1/2 or what ?
what did you stick the balsa down with ?
Sorry for the questions but they are all important to determine what glass or glasses to use !

[XstreamVking]

On a 1/2'' balsa, a 1708 bi-axial would be good. Cover it with some 3/4 oz matt to make it water proof. This is with poly or vinyl resin. With epoxy you could use some 1700 bi-axial and just resin coat it to seal it from getting wet. I am seeing a Stream in your pic, so that is what you are coring?

[Aaronhl]

Yes guys I have a HS Virage I am going to put a core, stringer(knees) and transom in very soon. Already have the boat in the garage on blocks and all the old wood ripped out.

I am going to use 1/2" thick balsa and epoxy resin. Using cabosil to thicken it as I put the core down. I have worked with epoxy plenty of times before as coatings, just not as much glass work.

[XstreamVking]

1700 is the weight I would use then.....If you want to go a little heavier, use some 24oz bi-axial. Main thing is to seal it up good. Roll some resin on the balsa and let it set up. Then run your glass over that and let it set up. Then flow coat the surface....Stringers could be on top of the core for more even load dist. Less stress points on the hull skin.

[Aaronhl]

So that is 17 oz 45 fabric? I was thinking of doing it like dwilfong he used 1700 all over the boat like the core and the floor

I am thinking 3 sheets of 1/2" marine plywood for the transom with a 1.5oz mat inbetween each layer..what do you think??

[XstreamVking]

Yes, on the 0/45 fabric. For everything. And I would skip the matt in the transom and use the same putty mix as you used for the core between the sheets and to bond it to the hull. If you were using poly then yes, use some matt. But epoxy is so damn strong and super adhesive it is a better glue than the stuff holding the plywood together. Save weight wherever you can.

[tunnels]

Yes, on the 0/45 fabric. For everything. And I would skip the matt in the transom and use the same putty mix as you used for the core between the sheets and to bond it to the hull.

0/45 ?? what kind of glass is that ???? never heard of that one before! would be pretty useless !!
IF YOU USING EPOXY resin YOU DONT WANT TO BE USING CARBOSIL TO THICKEN WITH !! has no guts what so ever ! actually makes the resin brittle ! check out the west system recommendation ! they are a really big help !

[Aaronhl]

Then what do you mix it with? the 403 stuff is too expensive

[Aaronhl]

And another question, how many layers of the 1700 over the core floor and transom?

[XstreamVking]

I used 1 layer of the 1708 oz bi-ply over the foam core in my V-King. For the transom, I would add some to the hull skin to get about 1/4'' thickness, install transom and then cover with 2 layers. 2 more over that where the motor bolts go thru is helpful. Stringers and knees, 2 layers is plenty. Floor depends on what is being used for core. Usually 1 layer under, and 1 layer over with an additional 6'' tab pc on the floor edges all the way around is good. So 2 layers at floor seam...

[Aaronhl]

Gotcha ok, I think my transom skin is like 1/8-3/16" so I will build that up with some 1708 fiberglass to 1/4" thick then put in my 3 layers of 1/2" thick marine plywood transom

I need to find a way to keep the transom straight, it has a slight curve in it. Not bad at all but noticeable with a straight edge

[XstreamVking]

Go to a scrap yard or metal fabricator and find a couple of pcs of straight steel ell angle (L) and screw from the outside into the wood possibly using the motor mounting holes. One pc at the top and one lower. Need the trans flat for sure....