Floor for tinny
Submitted by NORUN NOFUN on Mon, 2015-09-07 12:24
Gday guys,
Bought a little 390 explorer and wanting to fit a floor.
Im getting the supports made up and will weld in at some stage, so the floor will be roughly 100mm off bottom.
Not a fan of the floor they come with, these practically sit on the bottom of the hull.
My question is : What size plywood should I use ? Is 12mm to small or should I go 18mm ? I'm thinking 18 but also after opinions.
tombstone
Posts: 169
Date Joined: 14/10/10
12mm plenty, 18mm overkill.
12mm plenty, 18mm overkill. I did mine in 12mm just make sure you seal it well before putting the carpet on.
to fish or not to fish...as if there was an option.
carnarvonite
Posts: 8665
Date Joined: 24/07/07
12mm
Use 12mm marine ply with extra bearers to support it.
scotto
Posts: 2470
Date Joined: 21/04/08
hmmm
Personally, and if it were my boat, i would definately be using 18mm marine ply. 12mm to flimsy in my opinion.
tombstone
Posts: 169
Date Joined: 14/10/10
12mm not flimsy at all
12mm not flimsy at all Scotto, especially in a little tinny, if you had heaps of space between the bearers then maybe, got to also consider the extra weight using 12mm. i did my whole lot out of 12mm. and its strong as. if it were a bigger boat and beamier then yeah def use 18mm. for this project 12mm is fine. i did front casting, middle floor and rear casting, as you can see in my pic, also put a build thread up 3 odd years ago. 390 explorer is a great little bream cockburn sound boat. caught plenty off it. good luck with the project.
to fish or not to fish...as if there was an option.
scotto
Posts: 2470
Date Joined: 21/04/08
strongly disagree
12mm IS very flimsy, and I wont have it in any boat of mine, regardless of size.
the weight difference is minimal, and should probably not even be considered in the argument.
I am a commercial builder, and underestimating structural situations like this one, is the root cause of many failures.
speaking first hand, I own a (albeit large) tinny, and built a storage are (for the fuel tanks)/casting platform down the stern of the boat, around 12 months ago. I originally used 12mm marine ply, and built the whole thing before I was just about to carpet it, and realised it was too flimsy. it could barely take my body weight, and that was only about a 400mm span.
I ripped the whole thing out, kept the aluminium angle and flat bar, and rebuilt it in 18mm.
tombstone
Posts: 169
Date Joined: 14/10/10
Like this. all 12mm marine
Like this. all 12mm marine ply.
to fish or not to fish...as if there was an option.
NORUN NOFUN
Posts: 1035
Date Joined: 15/08/11
Thanks Tombstone. I bought
Thanks Tombstone.
I bought the boat as a project 2 weeks ago, and is bare bones 390 with 15 suzi and HD Dunbier trailer and only 2 years old
Im keen to do front, centre and rear decks.
I have the centre floor worked out with the braceing, but if you have idea's for front and rear, it would be good to hear your opinion.
cheers
tombstone
Posts: 169
Date Joined: 14/10/10
yep, mine was bare bones
yep, mine was bare bones too. no better feeling than having it finished off the way you want.
to fish or not to fish...as if there was an option.
NORUN NOFUN
Posts: 1035
Date Joined: 15/08/11
Great photo I'd like to know
Great photo
I'd like to know how you braced the front and rear.
Do you have any photo's of bracing ?
tombstone
Posts: 169
Date Joined: 14/10/10
hi Mate, i did do a post up
hi Mate, i did do a post up here a few years ago with heaps of pics. It was alot of fun and if you are a little mech/handyman orrientated it's quite easy.
to fish or not to fish...as if there was an option.
Bruce
Posts: 527
Date Joined: 11/04/12
Have used 12 mm on every one
Have used 12 mm on every one of my tinnies and never had any dramas
dano83
Posts: 790
Date Joined: 25/05/12
I'd go 18mm I had 12mm in my
I'd go 18mm I had 12mm in my tinny... wasn't to flimsy had a bit of flex in it but will bend over time that's for sure.
sea-kem
Posts: 14960
Date Joined: 30/11/09
If you go 18mm you are only
If you go 18mm you are only adding around 5-6kg of extra weight so for me it would be a no brainer. I'll be using it in my project Quinnie if I ever get to it
Love the West!
Jason P
Posts: 521
Date Joined: 16/02/13
Structural ply.
Marine ply is way expensive and overkill as it's designed for constant omersion in water. Painted structural ply does the job fine and is commonly used. It's not like it's going the be wet all the time.
DM306
scotto
Posts: 2470
Date Joined: 21/04/08
that is not good advice
Hmmmm i wonder how marine ply got its name, or why it was invented....
Each to their own, but there is no farkin way i would use anything but marine ply.
Structural ply (sealed or not) delaminates at the sniff of water. When you factor in this is a tinny that will be getting its deck wet extremely often, carpeted (holds moisture), probably be stored outside in the elements, then there is only one form of plywood deck that should be used. Unless of course you want to waste all your time and money and rebuild it all again in 3 months time.
Norun nofun, build it correctly, right from the start. 18mm marine ply, 316 stainless screws, and seal it with an enamel sealer (especially the edges: 2 - 3 coats). You wont regret it.
Swompa
Posts: 3871
Date Joined: 14/10/12
My boat is full of
My boat is full of structural ply. Just make sure it is soaked in polyester/epoxy resin...many many coats.
tombstone
Posts: 169
Date Joined: 14/10/10
marine ply all the way, and
marine ply all the way, and stainless screws, plus ali rivets where needed.
to fish or not to fish...as if there was an option.
epic restos and...
Posts: 226
Date Joined: 22/06/15
would seriously look into it
would seriously look into it but for the cost of ply and then the fact of the weight and chances of expansion and maintenance and labour I would seriously consider getting a ali floor fabed up as the price wouldn't be that much different worth a thought
grantarctic1
Posts: 2546
Date Joined: 03/03/11
Have to agree
At the end of the day the price difference would be small.
But for the average person doing the job them selves the ply would be easier to work with.
carnarvonite
Posts: 8665
Date Joined: 24/07/07
Removable
Wants to be removable so you can clean underneath regularly. I've seen a dinghy after the floor was removed for the first time with so many pinholes in it, it looked like the Milky Way when a light was put on the other side. All caused by small sinkers rolling about in water creating electrolisis
sea-kem
Posts: 14960
Date Joined: 30/11/09
Yep my floors come out once
Love the West!
grantarctic1
Posts: 2546
Date Joined: 03/03/11
Did some work
Did some work on a small boat last year, talked him into lifting the floor.
There was almost no space left, filled with rubbish, cans, bait packets and the occasional mummified wrasse . LOl
The stink almost made me chuck .
sea-kem
Posts: 14960
Date Joined: 30/11/09
Ha ha ha filthy bugger.
Ha ha ha filthy bugger.
Love the West!
axey45
Posts: 1758
Date Joined: 26/11/13
Wot about uniboard anyone
Wot about uniboard anyone tried this??
catchalittle
Posts: 1875
Date Joined: 04/09/08
Have a look at the ali
Have a look at the ali composite boards thats what was in my 3.7 dart and I glued marine carpet over it and it was strong as
Nathan
NORUN NOFUN
Posts: 1035
Date Joined: 15/08/11
Thanks catchalittle, never
Thanks catchalittle, never heard of them and will check out