Any better ideas how to make this insulated livewell/barrel?

I've gotta make 2 fiberglass barrels basically, sized on the inside to approximate dimensions of a 55 gallon drum (ie ~22.5 diameter) and the outside to allow for 1.5 to 2 inches of foam, ie 26.5 inch ballpark. Height will be fairly modest, 20 inch ballpark.

They will tuck ~40% under the gunnels on opposite sides of the hull, be fiber-glassed in place, with the overflows (will be flow through) exiting directly through the hull with a decored hole that goes straight through the livewell & hull. Mostly they are a livewell but there is a semi structural aspect where the gunnels could use some stiffening up/down, which is not a required piece of structure.

In thinking over how to make these, I've got 2 ideas that both utilize a similar concept:
1. build inside drum into a 1 piece part
2. secure structural foam to desired sidewall thickness to inside drum in multiple places (6 seems good), have strips of corecell and figuring that's as good as anything for this - purpose here is so that in later steps the sidewalls stay consistent and do not deform
3. wrap inside drum w/ outside drum, setting it into some putty/adhesive that is placed on the foam strips
4. tab/wrap outside drum w/ glass so it becomes one piece
5. pour foam into the chambers, slice excess, trim as needed to set into boat

Note: likely I'd cut a round out of laminated corecell, install it into the inside skin before wrapping the outside skin, to help maintain the shape. I could also put a temporary top inside to help hold the shape on the other end that just gets yanked out or cut off (the actual top will be the underside of the gunnel).

That above concept, as much open to doing differently as anything, but assuming I went that way I've got 2 methods I'm thinking that could be used to make the skins.

Option 1. Start w/ a 55 gallon drum (durr ) and mold curved parts off that that are 50% (or maybe more if thin so they can be peeled away). On the outside drum I'll just have to use an extra bit of the same material done one way or the other to close the gap, open it slightly up during install, throw some crank straps or whatever around it to hold it against the adhesive, once cured glass around it, pour foam, etc.. etc..

Option 2. To make the inside layup some thin fiberglass sheet, probably some 1.5 ounce CSM as it's floppy, but maybe 8 ounce cloth, wrap it 360 degrees around a temporary form - ie a piece of plywood cut to the right shape for top and bottom, glass the sheet together and wrap it a bit so the form is set - remove or cut away the forms. And then once the inside skin is built I can do the same w/ the outside by wrapping sheet around the inside part w/ the foam strips and all that.

Thoughts? Any easier ways to do this you can think of?

 

The idea to hole the hull and the tub are not ideal. The hole in the tub would require coring and access is important. So, the first thing I'd do is rethink the plumbing. Always the easiest plumbing is not. A clear hose you can see and access off the deck you will not regret.

I would approach the job differently. Find a plastic 55 gallon drum and get it spray foamed by an insulator; then shave it and laminate. Decore the area needing plumbing. Glue it into the boat, not with epoxy as hdpe doesn't bond well, but with an adhesive that is friendlier.

Check with the insulating folks about how to make it sticky enough. I'm not taking credit for delam..

 

Thanks!

I'm not sure I love that idea but the hard trouble w/ incorporating a plastic barrel into it is I can't tab to the skin.

So then there would be no way of sealing off that top edge of foam - I could indeed skin the outside, tab the outside to the hull, but on the inside the foam around the lip of the barrel would be exposed literally or practically.

Now I suppose I could go skin the entire inside of the barrel and everything. Let the plastic barrel just, be suspended in there, then I could glass right over the top and seal off the foam. But any water that somehow permeates the fiberglass on the inside would surely de-laminate, possibly do some weird stuff, on the inside, as like you point out you can't just fiberglass to most barrels I've seen.

They do make stuff like this though - any resin would likely bond to it famously. But I think essentially it's cardboard, not sure I like that either.

https://www.grainger.com/product/23...S4j5TQ-xWrCS5-tDQvhoCHmcQAvD_BwE&gclsrc=aw.ds

 

You have to use a different glue to bond to hdpe, or you mechanically fasten to it.

The idea of making a fiberglass barrel is quite horrible. Like you said; you could use the barrel as a former; then when you get to the top; you just bond some marine core to the fiberglass over the expanded foam and can do anything you like. If you make a roughened hdpe surface; it is not likely going to spin. You can also put marine foam on the base. Use the inside of the barrel as is, no foam. Then just use a sealant at the top...

I built a 4' long by 2' by 22" livewell. I built is from core and then insulated it with pink.

Another approach for you would be to thermoform two half barrels over a real barrel with foam core; laminate each side and tab them together. Much easier than your proposal.

 

The barrel needs the foam because it needs the insulation (this is a biological problem to overcome that we cannot change )..

I think I like the make 2X half barrel idea a little better than anything involving the plastic material - I considered that at one point actually. What drove me onto another idea was doing it like that you need a scored/scrim foam core, which I do have a bunch of that was bought cheap, but is an awful lot of expensive material involved to wrap a barrel for the purposes of insulation (ie 60-something inches per pass) versus using poured foam that is kinda a dead ringer for insulation purposes.

But it's a real valid option - probably the easiest/soundest way to really just make a fiberglass barrel. I'd probably build it 360 degrees then cut the barrel into 2 half barrels, then pull my parts off - 55 gallon barrels are cheap/available/disposable from various businesses who get product in them. That method I think, I've got 5/8 corecell that's scored/scrim - I'd wax a barrel, wrap it w/ glass, wrap it with a layer of 5/8 corecell bedded in corebond or some filler, probably let it cure then go fill the open scores with the same compound, run a second bedded layer of 5/8 corecell (call 1-1/4 enough insulation), then go wrap it in glass, allow to cure, then cut my barrel/part, remove parts, prep parts, tab together. That would indeed work.

 

Just use a barrel as a former and form it with glass; join the glass with tabbing and make four pieces for each barrel and pour foam.

 

Well that was one of my original options, coming full circle here ..

Yes can do half circles w/ the barrels. Just the outside barrel will be stretched open a bit, and with a little extra added, to make the 360 degrees since it's going to have a larger diameter/circumference. That would be a total non issue though, is nothing to flex a thin skin open a touch.

Doing it that way I would be back into using a strip of structural foam just as stand offs between the two barrels, so they hold their shape/center to pour foam in.

 

Do the wells have to be barrel shaped? A box shape would be easier to make with flat foam panels.

 

The fish can get stressed in corners..

 

A lot of baitfish get stuck in corners, can't swim, die, so inside must be rounded usually. Some do just sit there and flutter, but not mackerel for instance - they go round and round and round.

I have made livewells before and I probably would this time if it were sub deck or elsewhere, starting w/ a rectangle or square box, then I add the rounded corners by bending thin material in there. That is a very valid option, however on this boat they are going on the deck and 60% of them will protrude out where you walk by & will see them, ascetically round outside looks better plus takes up less space.

 

Presuming that the outside finish is important:
Make a round mold from something flat and shiny (formica, lacquered sheet of steel, etc.) so that the inside diameter corresponds to the outside diameter of the finished well. Fillet the bottom corner with wax, apply mold release. Gelcoat, and laminate to desired thickness.
For insulation buy some 2" rigid PUR closed cell foam, cut it into strips or kerf bidirectional. Cut a circle for the bottom. Butter everything with thickened resin and install into the outer skin that is still in the mold. You can interspread your corecell strips with the strips of PUR foam. To apply even pressure put a heavy duty garbage bag inside and shoot some expanding foam from a can. Remove the bag of foam, sand the inside round and laminate the interior.

If the outside finish is not important or you are willing to sand:
Make the barrel directly out of strips of foam, sand round and laminate the interior and exterior.

PUR foam can be laminated over with polyester, XPS needs epoxy.

 

HDPE doesn't really bond well with anything. I like your original plan with the foam. However an alternate idea would be to purchase some Divinycell or a heavy weight marine foam in 2" thickness if you can't find that maybe use the Pink Closed cell foam from Home Depot. regardless slice the foam with a carpet knife every inch or so on the outside and form into a circle and then wrap with fiberglass and epoxy. for your final layer cover it with fairing compound mixed with epoxy and wrap with HDPE plastic as a release fabric which will give you a smooth surface and then sand smooth.

Another idea is to make a 50% size wooden mold and cover with PVA epoxy/polyester/fiberglass then foam then epoxy/polyester/fiberglass then gelcoat/paint. then you can glue the two sides together and make a final shape.

Just a few different ways to skin the same cat. However I agree I don't like the live-well with full access to the ocean. Pumps are fairly cheap and if you don't want to carry a 55 x2 gallons of water around you can easily pump them dry.

 

Except he doesn't need to bond the hdpe barrel to anything...he only needs a lid and insulation...

 

Thanks guys!

One thing to mention, the overflow would not have access to the ocean. Livewells go on deck level - about 8 inches above waterline at the bottom, with the overflow about 17 inches over that. So water would get pumped in from the bottom (via a self priming pump located above waterline) and it would drain 25 inches-ish over the waterline via a hole through livewell + side of hull if I did it that way. To drain it you'd pull the plug, they drain out onto a self bailing deck.

 

Just to maybe explain a little better, here is a sketch and the approximate area under the gunnel where the livewell would be fit, marked by the cardboard circle. It would fit approximately 45% under the gunnel there. Just happened to have this pic from recent construction progress.

Normal operation of the livewell, water is pumped in continuously, it overflows from the hole towards the top (however that hole is implemented).

The insulation part - this is for certain bait species or situations where the overflow is plugged, an aerator is used instead. 2 situations where this feature helpful: one when we temporarily enter brackish water with salt water baits on board, other is certain species we catch that live near the bottom require colder water so we chill the water and similarly run an aerator.