Plywood floor underneath HP air floor?

[Franko Manini]

Hi folks, new guy here from Canada...

I have a QuickSilver 320 with an air deck. I love everything about it... except....

Once a year I take it fishing and leave it set up for about 10 days straight. I do a lot of sight fishing on lakes, and I stand a lot to see the fish. I find the air floor a touch wobbly, and standing on it all day, while comfy on the feet, gets to my back with all the wiggling.

Another issue I have is this odd welling up of water under the air floor while on plane. It is sort of cyclic, like a wave slowly building udner the boat, then eventually, the boat gets over or past this wave, then another one starts to build. It effects the handling a bit, with the the boat surging slightly as the "wave receeds". I can feel it under my feet and it is such a strange thing to a guy who has always used aluminum hulled boats!

I've double checked that the floor is inflated to the recommended pressure using a menometer, and I've also checked tube and keel inflation, floor position, engine position, trim, and cavitation plate height. All of these are well within specification.

I was thinking of taking a piece of 5/8" marine ply, and cutting it to fit underneath the air floor from the air floor batten near the bow, to the transom. My thinking is that this will provide both additional rigidity and help with this strange "wave riding" effect I experience on plane.

Has anyone tried this? Does anyone have other suggestions?

Thanks,

Franko, the New Guy.

[John Kennett]

That sounds like pretty standard behaviour for this type of air floor. I had a 340 and recognise your description of the symptoms!

I'm not sure whether you'd manage to fit a ply floor under the air deck, but provided you don't chafe the tubes with it you're unlikely to do any harm trying.

Any chance of picking up a trashed 320 with a wood or ali floor and using that instead? I think the floor types are interchangeable, but are silly money to buy separately.

[rob peters]

I have a suzumar air deck and it does exactly the same. I was trying to think of a similar idea in using a stringer down the middle from transom to bow.. It always seems to bend about 2/3rds of the way down. I am sure if it didn't bend performance would greatly be improved.

[Bighag7]

Yep,
It's an HP floor thing. I have a Zodiac Futura 2 fastroller, 4.2 M and you've just described exactly my experience. I cured it by spending £200 on some Marine Ply, used the HP floor as a template and with a little jiggerry pokerry and some copying of an original hard floor I managed to get it fitted and it works a treat.
And now I've overpowered the boat with a 35hp (rated for 30!) it goes like a rat up a drainpipe, planes brilliantly and turns better than before since the ply floor pushed the speed tube into the water and doesn't give.
If you're not confident about fitting it yourself, buy the wood and get a friendly carpenter to do it.
Hope this helps.

[Franko Manini]

Thanks for everyone's input. I think I'm going to give it a go. Most of the time, I am out on small lakes for the day, and it's more of a benefit to have the quick setup and takedown ofthe HP air-floor. But for those occassions when I have the boat inflated and in the water for days on end, it would be a treat to have the additional stability, and dare I assume performance, at the small cost of bussing around a hunk of plywood.

I happen to be a pretty handy guy with a full woodshop at home, so it shouldn't be such a chore to template it out using the existing air floor, cut it out, fair the corners, and roout the edges smooth and round.

I'll put a coat of epoxy on it and it will probably outlive me.

I'll report back when it's all complete.

Cheers,
F

[Bighag7]

Hi Mate,
One last thing, make sure you get pictures or even plans of the original floor as you need to get some slides that run between the sections that keep it in place and they need to be really strong. I got some old aluminium ones from an old floor.
Good luck and let us know how you get on.

[lockieboi]

I am in the same boat! (excuse the pun!)

Be interesting to see how you get on, make sure you post some pics.

Thanks for being the test dummy on this!

[azzurro]

I have 3 thoughts about this:
- Will the floor stay close to the water surface? Otherwise your boat will be less stable.
- "Sentine effect". You may need to pump out water.
- If so good why is it not offered as optional package?

Good luck, the benefits expected are the worth the risk.

[Bighag7]

The Hp floor is light and easy to transport, it also means you can use a lower powered engine. The ply floor works brilliantly and provided it is fitted correctly will push the speed tubes in to the water as intended.

[stretch]

i did just that on last boat, 12' sib with air floor, but i used a 1/2" MDF board, gave it 2 coats of fiberglass resin! boat was alot more rigid, and change nothing about how it handled!

Marc