Who has made a light weight floor?

**aaron78viper** · 03-13-2017, 09:10 AM

I spoke with someone on here about a floor for my viper, I trust his advice for a solid floor that will stand the test of time, but I had an idea for a lighter weight floor. As many of you know, a viper has a floor about 3 feet wide, with two stringers about a foot apart in the middle. i feel that a balsa core floor, with two layers of glass on each side would suffice for this boat given the short span across the floor from sides to stringers. Has anyone tried to build a light weight floor with balsa core or foam core???

**JBMac** · 03-13-2017, 09:52 AM

Looking forward to the answers you get. This is the only part of my rebuild I haven't decided on yet. I know a lot of decks that are meant to be walked on sailboats are balsa. I'm personally looking at Corelite PET. My Valero floor is a similar size- 2 stringers a foot apart, total floor width about 40"

**97 TWISTER** · 03-13-2017, 03:33 PM

I have used thermo-lite board made by Space age synthetics. It's over 100% lighter than encapsulated wood come pre sanded and very easy to work with. The only draw backs a price and you can't screw into it. You glass in mounts or use T-nuts with panel bond adhesive. I used panel bond for my seat base, foot throttle and battery tray in drag boat and that's going on 4yrs ago. The price per sheet seems high but when you factor in cost and time of making wood water proof its not that expensive. I also have used it for transom, knees, bulkheads and stringers. Just another option hope it helps.

**David - WI** · 03-13-2017, 07:39 PM

I did my HST floor with 1\2" NidaCore. It was 30# lighter than the (4 x 8) plywood I took out, according to my old notes.

**XstreamVking** · 03-14-2017, 08:31 AM

I used 1/2'' 12# density penske core board with 1 layer of 1.5 oz matt on both sides in my V-King. Very strong and light. If I did it again, I would go the same route. jm2cts

**One Oldman** · 03-14-2017, 11:04 AM

On my current build, I am using 3/4" laminated Carbon-core honeycomb. It is around 30# per sheet and reasonable for a composite, around $190. I have been using it for stringers and knees. So far my only complaint is that everywhere a solid bond is required, I have been filling the open cells along the edges with putty for an increased bond. I don't know if this is really necessary or not, but it makes me feel better although adding another step. LOL It will not hold screws well, which I knew when I bought it, so good planning is essential. The step to get it to hold screws is easy and simple Also the 3/4" size was chosen simply to standardize material throughout and I needed 3/4" stringers and knees. 1/2" would have been a few pounds lighter and probably been plenty strong enough for decking. I am spanning around 6' or less and supports will be 12" or less.

**AlaskaStreamin** · 03-15-2017, 06:04 PM

Aaron Wacholtz put a honeycomb floor in his Virage.

I made balsa panels as a floor over my sponsons (you can see the edge next to the side panels) but decided on plywood for the center for the shear.

**aaron78viper** · 03-16-2017, 09:06 AM

I think I'm going to try the floor built just like the balsa core in the hull, a couple layers on top and bottom. cut to fit, seal the edges real good, glue it down and glass it in all around. ill try to make a box out of my stringers like factory vipers had to glue the center section down.. I am confident that will do the trick.. Seeing how many various ways you all built your boats and you all are happy with the result, I do not see it being a problem.
Thank you guys for you ideas and replies, your experience is much appreciated

**tunnels** · 03-16-2017, 06:34 PM

Originally Posted by aaron78viper

I think I'm going to try the floor built just like the balsa core in the hull, a couple layers on top and bottom. cut to fit, seal the edges real good, glue it down and glass it in all around. ill try to make a box out of my stringers like factory vipers had to glue the center section down.. I am confident that will do the trick.. Seeing how many various ways you all built your boats and you all are happy with the result, I do not see it being a problem.
Thank you guys for you ideas and replies, your experience is much appreciated

A couple of layers of glass ?? what kind of glass ?? the glass is whats going to give you the ridged strength and what you choose and how you make it is the key !!
So be more specific as to what you intend to use !!Definitely not WOVEN !!its possibly the worst glass to use in that kind of situation !!! Do you know the reason why ??

**Capt.Insane-o** · 03-16-2017, 07:01 PM

Originally Posted by aaron78viper

I think I'm going to try the floor built just like the balsa core in the hull, a couple layers on top and bottom. cut to fit, seal the edges real good, glue it down and glass it in all around. ill try to make a box out of my stringers like factory vipers had to glue the center section down.. I am confident that will do the trick.. Seeing how many various ways you all built your boats and you all are happy with the result, I do not see it being a problem.
Thank you guys for you ideas and replies, your experience is much appreciated

Diab used to make and still can I suppose a sandwiched foam panel that is fantastic. Strong , super light and will not absorb moisture. It's the best thing ever I have found for panels bulkheads floors and to some extent stringers for our little boats. Incredibly easy to work with too.

**GregAdams** · 03-16-2017, 07:27 PM

Crunch the numbers to make sure it is "lightweight". Put some thought into how you are going to bond the edge of the floor to the hull. Aside from direct impact, sandwich panels often fail at the edge, because of the way they are finished, or bonded to other panels. Consider the weight cost of bonding in different types of panel to the hull. Consider the weight cost of attaching mounting brackets and seats to different construction floor panels.

**speedman79** · 03-16-2017, 09:51 PM

Use plywood, you'll go thru more money and more hassle to mount your seats when the ply really doesn't weigh much to begin with. The extra resin and glass will add the weight your saving on using balsa.
JMO

**tunnels** · 03-16-2017, 10:52 PM

Originally Posted by speedman79

Use plywood, you'll go thru more money and more hassle to mount your seats when the ply really doesn't weigh much to begin with. The extra resin and glass will add the weight your saving on using balsa.
JMO

and how you going to seal the ply?? resin and glass ?? sort of chasing you tail !! just need one tiny hole and the water gets in and gets heavier as time goes by !!

**aaron78viper** · 03-17-2017, 09:07 AM

tunnels, im guessing the woven stuff is far less rigid because the strands are pre kinked, which make them softer under compression and tension. I would try some +/- 45 1700 like i did my recore with. its pretty light weight and is super rigid in the hull. I dont see why it wont work in the floor. Im guessing the floor wont see the same abuse as the hull

**XstreamVking** · 03-17-2017, 10:09 AM

It's the windows in the woven glass that let in the moisture. Can't beat matt for sealing things up....1708 would work well too, but is kinda overkill.