Plywood alterative floor
- Thread starter butch27
- Start date
fletcherson
Well-Known Member
I am considering aluminum, but not to that point yet.
Plywood comes with numerous different cores, different densities and therefore different weights. Don't think that just because Home Depot doesn't have what you want it doesn't exist. You could try some 1/2" Baltic birch plywood, it is 9 ply as opposed to 5 - 7 ply douglas fir ACX or CDX. But realistically the floor is going to be about 16 sq. ft., plywood only weighs about 2 lbs. per sq. ft. Hard to find much savings in that small amount.
kcline40
Member
Why do you have the concern about the weight? These cars are light as a feather. If its installation I can understand its heavy to lift onto a frame, but realistically won't the fiberglass and resign also add weight to the body, the seat and interior will also add weight. I supposed you could try an aluminum floor pan. but that seem like a lot of work and everything would have to be laid out on the frame prior to any body work getting done. I think the floor would also have to be removable so you can take it out to make adjustments and be able to reinforce areas where you make cuts. It just seems like a lot of extra work for something that no one will see once an interior is installed. I would stick with wood but you could explore the different types of wood. Corvettes use Balsa wood and carbon fiber. Try that and let us know.
We use a fiberglass floor and then install a honeycomb material over the fiberglass floor and glass over the honeycomb material. It is light weight material. They use the honeycomb material in the RV and boating industries.
I'm planning on using this
##HTMLENCODE[Coosa Composite Board - Bluewater 26]##
Or one of several similar composite boards.
##HTMLENCODE[Coosa Composite Board - Bluewater 26]##
Or one of several similar composite boards.
- 30% lighter than plywood of similar structural properties
- No mold, mildew, or rot issues
- No special tools required
Yeah, it's got a hefty price tag, but around $125 extra for a half sheet is not all that much in the scheme of things. It's a one time expense on something that is functional (longevity & lightness). On these cars we typically spend a lot more on items that are largely cosmetic.
I know it is typically said that if you seal plywood there will be no moisture related issues, but in my mind that is a matter of luck. Long ago and far away I used to rehab pontoon boats. We tried several recommended sealing methods, including fiberglassing, and it was always a crap shoot for how long they would hold up. When I decided to take my shot at building one of these things, one of the first things I did was call a buddy who runs a boat repair shop...the Coosa 26 was his "do it right and forget it" recomendation.
There are other marine composite boards that are slightly less expensive and probably sufficient for the job...King Starboard and Seaboard come to mind. These can frequently be found on ebay in full sheets and various cheaper cutoff scrap pieces, but I've never seen Coosa on there.
2old2fast
Active Member
You're comparing apples to oranges , unlike boats , these cars are not [hopefully] immersed in water , if you get caught in the rain , the little bit of water drains/dries out quickly , any holes can be sealed during the glass process , using marine ply is more than sufficent , both in water resistance & strength , saving less than 10lbs. is not very cost-effective , there'sw been literally thousands ofthese cars built w/ wood floors & unless left out in the weather constantly , I can't believe "wood rot" would ever be a problem nor have I ever heard/read it being mentioned....
dave
dave
fletcherson
Well-Known Member
I think if you use treated plywood, you will be fine, but I bet that marine composite, as nice as is looks, likely has a non marine counterpart that is less pricey? It looks very similar to composit decking material for porches, etc... Cool idea though! My t was originally built in late 70's and had the original plywood floor in it. It was not left out all that time, but wasn't pampered either. Real exterior rated plywood will take a lot of water, as long as it doesn't stay wet, it is pretty resistant to rot from my experience in the building trades. The ends are the weak points, seal them.
For the most part, the composites are not used where immersed...they are used for decking. Just like the floors of our cars, boat decking is subject to cycles of getting wet, and the water draining and/or evaporating off. Given the cycle is repeated more often on most boats, but it doesn't take many cycles to start mildew, mold, delamination and/or rot.
The idea of sealing up plywood really is hit or miss. If it were truly as easy as slapping on some fiberglass and paint to reliably seal plywood, the boat owners, builders and repairers would not be going to the added expense of the composites...and there would not be enough demand to support several composite decking manufactures. What sold me on the composites, for what ever its worth, is my personal 10 or so years of experience replacing plywood pontoon decks and RV floors that were frequently less than 5 years old.
You brought up something that is a factor for me...and maybe some others. Mine will be out in the weather constantly...before and after completion. I have no garage, and no place to put one. My work area is just a few feet from a heavily wooded area, so anything requiring drying or setting time is subject to contamination. Once finished, my car will live outside, with the only protection being a car cover. Since the composites have no need for any fiberglassing or even painting, it's just a matter of cutting it out and using an appropriate adhesive to fasten it to the body. The adhesive need only be exposed for a brief time.
Of course, it is up to each to decide if the composite decking is worth the added cost. For me it is. But then I do have genetic disorder preventing me from doing things the usual way.
My signature spells out my approach to my project...
“Simplify, then add lightness,” -- Colin Chapman
For the typical T-Bucket with a monster motor, giving a second thought to the weight of individual components is not a high priority. In my case, with a little 150 or less horsepower V6, weight is the enemy. Where ever possible and affordable I'm going with light weight components. Other than going with an aluminum floor, with the associated fabrication, the composites are the best bet I've found for flooring...and other typically wood components.
2old2fast
Active Member
Old drag race saying was "every 100 lbs. is worth a tenth" That being said , 10 lbs. is worth a hundredth , nothing I'd spend extra $$$ on , LOL
dave
On it's own, assuming it was a drag car being built, the weight savings of the composite alone would not make the extra cost worth it. But as a part of a concerted effort to reduce weight, those 5, 10, and 20 pound savings add up to a real advantage...especially on the street.
"Adding power makes you faster on the straights. Subtracting weight makes you faster everywhere" -- Colin Chapman
It's hard to argue with Chapman's philosophy of building light weight cars...countless sports car wins, 7 Formula 1 constructor titles, 6 driver championships, winning the Indy 500, and 60+ years of building performance street cars is nothing to sneeze at. The modern Formula 1 and Indy cars are direct descendants of his approach. Lotus' current low end street car, the Elise, weighs under 2000 lbs, with a now days tiny 134hp engine. This works out to around 14.8 lbs per hp. The Elise manages 0-60 times of 6 seconds.
My car's target weight is around 1500 lbs, with a similar around 135hp engine. This works out to around 11 lbs per hp. I know my car will never be a match for a Lotus Elise...straight line or in the corners...but it should be no slouch as a casual cruiser on the street.
fluidfloyd
Active Member
Chapman had it right. Build them lite and worry about adding weight is the way I think.Lite weight plus low HP = performance. Besides, it helps keep one's creative thought processes flowing. Just my thoughts on the subject.
George
