Mounting Internal 36 gal Plastic Tank

[epresutti]

Folks,<br /><br />I am mounting a 16" x 69 3/4" x 9 3/4", 36 gal. Plastic tank in my rebuild (18' Mitchel), I have plenty of room between the center stringers. I understand one of the bigest problems with these tanks is abrasion. Several of my boating buddies recommended using an old inner tube between the tank and the hull (I am mounting internal in the bildge) and also between the mounting points. Is this OK?<br /><br />Additionally, the mounting instructions say allow for 3% expansion, this would be about 1/2" in width, 2" in length and 1/4" in height. And "DO NOT FOAM THE TANK IN IT MUST BE VENTED ON ALL SIDES". There are four (4) mounting notches on the top of the tank.<br /><br />My big question is what type of material should I use to mount the tank and still allow for the expansion?<br /><br />I know Tempo sells spring steel (or aluminum) clamps, they didn't seem sufficient to me to keep the tank from moving in heavy seas.<br /><br />Any and all help is much appreciated.<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.

 

[Bob_VT]

Re: Mounting Internal 36 gal Plastic Tank

How about closed cell foam strips? You know when you visit walmart they sell those camping pads for sleeping bags. That is 1/2" closed cell foam that will not absorb water. Cut one into strips and mount the tank with that and stainless or aluminum straps. Don't wrap the tank but support it the same way a car gas tank is supported...just in a few places. Considering the length (69") I would support it every 15" with four supports.<br /><br />Bob

 

[epresutti]

Re: Mounting Internal 36 gal Plastic Tank

Bob_VT,<br /><br />Thanks, will check out the foam. Strapping sounds like a good idea, I found another instruction sheet that was using strapping.<br /><br />Any other ideas are welcome, I still have some work to do before the tank goes in.<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.

 

[f_inscreenname]

Re: Mounting Internal 36 gal Plastic Tank

When my boat was built they installed a 60 gal belly tank.The only thing they used between the tank and hull was that green fake grass carpet. After 30 years it held up well. Made for outdoors,it drys out fast and allows air to move (if you use a meterial that dose not adsorbe water it will need to breath so the water traped between the tank and what ever you use will dry also).Even if you dont think it will get wet the tank will sweat and couse water build up.<br /> On my old boat I used those retchet straps you get Home Depot. They are a lot cheeper then most tie downs and you can get the tank real tight.

 

[epresutti]

Re: Mounting Internal 36 gal Plastic Tank

Guys,<br /><br />Thanks for the replies. I checked on the closed cell foam, doesn't look sturdy enough to me.<br /><br />I like the idea of the ratchet straps with nylon strap.<br /><br />The "fake" grass sounds good to me too. I had some up in the anchor well before I started my reabuild and (boat is an 1986) and it was in good shape.<br /><br />Unless anyone else has any suggestions I think I am set.<br /><br />Thanks again.<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.

 

[Hawkeye1]

Re: Mounting Internal 36 gal Plastic Tank

I just installed a 100 gal poly tank and talked to the tank mfg about the installation. They recomend Neopream rubber for under the tank and anything touching it, like a hold down. I used 1/2" thick 2" wide ribes every foot or so. Per there recomendation. I used the firm hardness neopream as it come in 4 ro 5 different hardnesses. Here is where you can get it and a million other things. I cant do a direct hyper link but its under raw materials and rubber.<br /><br /> http://www.mcmaster.com/

 

[epresutti]

Re: Mounting Internal 36 gal Plastic Tank

Hawkeye1,<br /><br />I take it your ribs were made out of some material other than the rubber, or did you use the rubber as the ribs?<br /><br />Thanks for your help. I checked out the site, they want lots $ for neopream.<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.

 

[Hawkeye1]

Re: Mounting Internal 36 gal Plastic Tank

Ed, I molded my ribs out of thickened epoxy. I used a 2x4 cut to the shape of the tank to tamp out the pads of epoxy leaving a 3" gap down the middle for water to drain. Linned those with the 1/2 firm reg neopream. They got like 25 different kinds of neopream and some are very expensive. All you need is a 36" wide x 12" long. Thats the cheapest way to slice it. You can cut 12 18 x 2" strips and that should be plenty to work with. Here is a copy /paste of the add with pn of what I used. It was like 26$ a foot x 36. Its good stuff to. I used 3m weather strip adheasive to glue it down.<br /><br />Pn 9455K68<br /><br />Plain Backed Commercial-Grade Neoprene Rubber 1/2" Thick, 36" Wide, 60A Durometer <br />$ 26.96 per Ft.

 

[epresutti]

Re: Mounting Internal 36 gal Plastic Tank

Hawkeye1,<br /><br />Thats the ticket <br /><br />Thank you very much.<br /><br />I will be posting a history of this project AFTER! my boat is back in the water (post maiden voyage).<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.

 

[Hawkeye1]

Re: Mounting Internal 36 gal Plastic Tank

Ed, when my tank expanded it was more of the sides and ends that expanded not so much of the bottom edge and hard corners. Hard to explain but it kinda bellys out in the middle. I was expecting mine to grow 2.5" but it never did on the bottom, maybe 1/4 to 1/2". So keep that in mind when fitting for you pads. Here is a link to a picture of my tank hole. I still had to fair out the pads to make a good flat surface to glue the neopream to. Remember the hold downs will need to be linned with the rubber also. I have mine blocked in on the ends and top instead of the ratchet strap. Just was easier for me. Again every thing touching the tank has the 1/2 rubber barrier. <br /><br /> http://photos.yahoo.com/bc/formula2....com/bc/formula2332000/lst?&.dir=/boat&.src=p h%26.view=t

 

[epresutti]

Re: Mounting Internal 36 gal Plastic Tank

Hawkeye1,<br /><br />Thanks, inside my hull I have a "keel", which is a 2x4, then the hull curves up from there. So I think I can use the keel as a center support and put the pads on the curve.<br /><br />Thanks for all your help.<br /><br />Safe boating to all.<br /><br />Cheers.<br /><br />emp.