Step Three: Building the Fiberglass Gas Tank

In this video, Harry Spear shows how to build a fiberglass gas tank. To learn more head to Spearboatworks.com

[@icarussisyphus5201]

I can never understand how people smoke everyday of their lives to be 100 or work with sanding fiberglass with no mask but live healthy lives. Awesome video. Thanks for this great idea!

[@sailininov]

Love this video! Very helpful, thank you

[@TheBlueOceanDiver]

Is a very nice and clear explanation, thanks you for share it with such detail

[@magnumopus00b]

Beautiful job

[@Hisslave1]

You're the man Harry! As good a craftsman as a fisherman and hunter. I miss seeing ya'll. I'll never forget our bowhunt on St V. Ray

[@harryspear1948]

Ray, we must get together soon. It would be great to catch up. Blessings Harry

[@wesleywillard]

This is fantastic 🙌

[@tracypippenger4806]

Nice never knew how that was done I need to own one of these skiff someday

[@harryspear1948]

Diesel won’t break down a tank made with vinylester resin. Ethanol is the culprit to worry about. If fuel has that you need to coat the interior with an Epoxy vinylester such as Novolac Vinylester.

[@consaka1]

What does it cost and where do you find it?

[@hemengfordjour7205]

Very good sir

[@josephmirabello9207]

Thanks for sharing

[@harryspear1948]

You are welcome

[@harryspear1948]

There are resins made that are impervious to ethanol. Not sure of name but you can purchase them and cost the inside of the tank and baffles before you glass the top on. That way you can use any gas.

[@Micington]

Isophthallic resin?

[@Micington]

You’re a crazy man not wearing long sleeves grinding haha thanks for video man!

[@Fulcrum205]

Guys production builders use prefab tanks because they save on labor and can be installed by lesser trained personnel. FG tanks work. Use ethanol free gas if you use poly resin. If you can't get ethanol free then you need to use an epoxy resin. The process is still the same.

[@blackbeardboatworks242]

Great stuff! Did you use polyester resin for the tank?

[@ericjohnson957]

Hey harry…I’m in the process with a skiff rebuild. I am so glad to have found your channel. It has helped a lot. Question about gas tank. How do you secure it when on the water? Is it just set underneath the deck? I guess a portable gas tank is “free floating” as well. Just trying to plan this out and have it make sense in my head.

[@harryspear1948]

Make L shaped tabs and glue them to the deck. That will keep your tank in place.

[@harryspear1948]

Vinyl ester resin is impervious to gasoline as long as there isn’t ethanol in it. Use marine gas for long life of the tank.

[@ubacow7109]

Is it truly impervious or just chemical resistant and will need be replaced few years down the line?

[@timleonard86]

Do you have a video showing how to make a good prep table

[@TheMarcel1984]

Great work! But why tank in front of boat at first? That aluminium flange must be screwd on for later posibility of cleaning or some work inside.

[@KiwiTim]

Hi Harry, loved that vid, great skills. I’ve got a small fibreglass boat that’s 14.6ft long (4.42m) and I want to build in a tank in a similar way to yours. I was wondering why you have to build it as a removable tank, as I would prefer to build it as a built-in permanent tank. Thanks from here in New Zealand

[@harryspear1948]

For me personally I would much prefer to have the ability to remove my fuel cell if needed. All you have to do is line the area you’re building the tank to with plastic and it will release from the boat and the plastic will pull off the tank once it’s fired off. Good luck with your project. Blessings Harry

[@consaka1]

I would prefer a removable tank just thinking ahead. If something went wrong with the tank it's easy to remove and fix. If you boat Hull gets damaged in that area it's easy to pull the tank and fix both. A built in tank would be a pain if you ever needed access for any of the reasons I listed plus some I maybe didn't list.

[@renatoramacola7707]

Very nice ...how many layers did you use to seal the top ?

[@waterboymuz72]

Where did you get the lid piece with the filler, sender mount, breather etc? I am looking for something like that for my fuel tank I'm building.

[@vedranzaninovic9177]

Hi Harry, can you tell me how many layers of roving did you do in total. I need to do a black tank for a toilet on my boat.

[@josephcrawley3095]

How much resin did this project take? And what weight of mat did you use?

[@liamstone3437]

It looks like vinyl ester resin is best for tanks as alcohol eats everything else. Do you find this to be true? I hate to buy a special resin for a small outboard tank (vintage tank is not available now). Is there a coating that can line a polyester tank to protect it from fuel additives? What are your thoughts?

[@terjeloe2995]

Thanks for sharing your process. I am planning to build a diesel tank. I have ordered vinylester. I am planning to build the walls with divinycell and I can get some for free, but they are covered with epoxy and kevlar. Do you know if the vinylester will adhere to the epoxy? I know polyester won't, but googling it I find different answers.

[@harryspear1948]

If you sand the entire tank after gluing the panels together then glass them fully I don’t believe there could be any problem. Good luck. Try google for adhesion compatibility.

[@harryspear1948]

Mat + 1708 + 1708 + mat is all you need . Remember to lap the material n all corners.

[@infomax2008]

I am thinking use this method to make a gasoline tank under cockpit floor. Can it be done for gasoline?

[@thalassobiote]

Is there any need for some protection on the inside where resin stays in permanent contact with fuel?

[@zacharywinters9413]

Don’t use fuel with ethanol. And you should be good.

[@disscombobilated]

2 questions. I have a few gallons of USComposites slow cure epoxy resin. Do you know if this will be ok to construct a gasoline tank for my boat? and where can I get one of those aluminum manifolds that you use?

[@harryspear1948]

Ezell Industries Perry Florida. I would make the tank using vinylester resin and paint the interior with the epoxy. Sand the cured glass first to insure a good mechanical bond before using the epoxy.

[@kairyurider]

Do you have to use a special resin for fiberglass to hold has without breaking down?

[@PrasenjitMondal-nu8xr]

Good

[@harryspear1948]

Ezell Industries Perry Florida

[@joegonzalez5668]

Complete newbie here! My boat builder, here in Panama, is constructing a 90 gallon tank for my 25' Caribe Pro. There is a design flaw that creates issues with the gas tank. Perhaps I misunderstood but I think he said he coats the inside with gel coat. I could be wrong. Thoughts?

[@harryspear1948]

Can’t hurt. Better with epoxy if using ethanol

[@harryspear1948]

No tabs. Yes if you disconnect the fill from the deck the tank will slide aft and is removable.

[@harryspear1948]

I wouldn’t be building fuel cells this way if they didn’t work.

[@jameshart4200]

But will it hold up with gas?

[@labronragon3022]

Where can I purchase an aluminum top with fittings like you used? Thanks

[@harryspear1948]

Ezell Industries Perry Florida 850-578-2558

[@americanbully9583]

How did you use this fiber glass with no long sleeves please let me know I alway itch from the fiberglass I have to know your secret.😊

[@HOOKSandHOOCH]

Where do I buy that aluminium plate?

[@timleonard86]

Sanded to what grit Metal to glass?

[@TheBossStudioZ]

When you say plexis what are those? Can I use silicone to glue down the aluminium sheet onto the fibreglass tank?

[@harryspear1948]

Plexus is a two part epoxy bonding glue. Negative on silicone!!! You need to insure that your tank won’t leak. After you glue it sand and glass the edges. Overlap by 2”

[@TheBossStudioZ]

@@harryspear1948 Thanks for reaffirming, any specific expoxy glue that I should be aware of? I found MarineTex epoxy, but unfortunately it is not sold here in Malaysia.

[@user-ho9uk3id2j]

Peace be upon you, how are you, my brother, I have a question. Is it possible to manufacture a gas cylinder with fiberglass? Please advise with the required specifications.

[@harryspear1948]

What is a gas cylinder?

[@ShimazuHanaji]

May I be out of topic? I was wondering if I could use the fiberglass resin as an interior coating for my Motorcycle Fuel Tank? I'm really worried that it might melt the resin over time. Can you please help me?

[@harryspear1948]

What is the tank made of? Epoxy might seal better. I would do some research before using any of the above remedies. Good luck with your project.

[@ShimazuHanaji]

@@harryspear1948 thank you! I was literally waiting for a response. 😅 I'm not really sure what my tank is made of but it's a 1978 TS185 tank. It was cleaned up and restores but I just want to make sure the rust won't come again. I want to know if this resin if good material for my tank's interior.

[@ShimazuHanaji]

@@harryspear1948 i'm also worried that the gasoline might melt the resin. So I have to asks experts opinion on these matters. I'm doing everything by myself restoring my uncles bike.

[@cardinhamkilligrew9712]

i am working on fiberglass waste tank. what should i use as a resin or epoxy on the woven fiberglass fabric ? new to this....

[@harryspear1948]

What it the tank holding? Dimensions?

[@cardinhamkilligrew9712]

@@harryspear1948 it's about a 15 gallon tank

[@bushmancustomsuganda98]

Hey Harry.... so I'm thinking of building a motorcycle tank out of fiberglass, but my worry is petrol eating through... any advice on how to avoid this?

[@harryspear1948]

Use epoxy resin and 10 oz cloth and cover your leaking tank. Fair sand and repaint

[@bushmancustomsuganda98]

@@harryspear1948 I'm actually looking to build one completely from scratch. Do I need to use a specific resin or gel coat?

[@harryspear1948]

No sir, Easiest way use H60 core and poly or vinylester resin. I would make a strong back table to build your boat. Build transom first Bottom second Build frame for the keel and the stem Fasten the sides to the bottom and make sure they are equal. Make the first and then trace it out on the next piece of core That should ensure that the pieces are equal. Good luck!

[@bushmancustomsuganda98]

Thankyou Harry

[@svflapjack8770]

Do know how the resin would react to diesel?

[@Fulcrum205]

Resin works fine with diesel. Tons of old sailing yachts out there with integral fuel tanks laid up with FG and poly resin

[@michaeldanilov9026]

So what materials to use on the fiber if it's gasoline tank need to make 100liter

[@michaeldanilov9026]

Not diesel

[@harryspear1948]

Vinylester resin 1&1/2 oz matt and 1708 biaxial fiberglass

[@harryspear1948]

Use non ethanol fuel!

[@luvthigod]

IS THERE ANYTHING YOU CANT MAKE OR FABRICATE ? 😊

[@Orlosthedruid]

why would you use fiberglass for a fuel tank and not welded aluminum or stainless steel? I would always go with aluminum for modern fuel. Weld it up and then set it in some type of foam or resin cradle. I admit, I have never made a fiberglass fuel tank, but it just seems to me that the polyester resin would be dissolved eventually in the gasoline? especially the modern fuel mixes.

[@joesloan1724]

Where can I buy the components to build?

[@harryspear1948]

Google fiberglass supplies in your area. That should do it. Good luck!

[@consaka1]

I came here because I need to figure out how to build a fuel tank for a Husqvarna GT2254 riding mower. This mower has the fuel tank under the seat and under the fender. It's shape is rediculous and it's disintegrated pretty bad from the sun. Of course it's not made anymore and can't be found anywhere. :(

[@harryspear1948]

Sand the tank. Wipe down with acetone. Buy quart of epoxy resin and one yard of 10 oz. fiberglass cloth. Wet tank and cover with cloth. Make sure you stretch the cloth around . It’s ok to fabricate using pieces just make sure you overlap joints. Use a small 2” throwaway brush. Wrap tank with two layers. Easy Peazy!

[@ScaniaFung]

u need mask when u cut and sand fiberglass

[@Rodneydncn]

I've been looking for a way to build a custom low profile fuel tank for my project boat and this is it!!! I'm using 100% epoxy resin to build the tank. It will be removable like yours. 100% epoxy resin over 1708 . Sound like a plan or am I missing something?