A friend has a Kyosho Jet Arrow electric boat. It has a 2-piece ABS hull, with some type of yellow/tan colored glue from the factory holding it together. He would like to strengthen it with carbon cloth on the hull interior.

Is there any method he could use to split the hull? This glue is tough, and seems impossible to cut with a blade.

Could sand the inside where it is with 80 grit sand paper and use epoxy reson with the carbon fiber cloth..But you could also get perma poxy plastic epoxy from advance autoparts.. Works great with plastics and fiberglass and metals..could sand it what I said without adding carbon fiber cloth and just spread the perma poxy on the seams..

Let me explain a little more. The hull is glued all the way around. There is an upper hull holding the motor and etc and the lower hull which is the V. There is a 1/3" wide strip of flat plastic seam running all the way around the hull. This seam is sandwiched with a yellow glue.

We cant figure out how to split the hull apart without harming it. My idea was that maybe you could heat the hull, and the glue would soften. But ABS melts around 220F, so it would have to be very carefully.

I was just windering if anyone had seen this type of glued hull split before with any luck.

heres a better idea?? You could use a die grinder with a cutoff wheel on it or a air cut off tool and ease the trigger and cut down the seam with it and then sand it..heat gun might melt it to qickly..

Its always possible that if the seam is that strong, it doesn't need strengthening........

You also may have some problems with the resins not adhering to the plastic, even if it's scuffed up. The bond that it would have may not be worth the effort. Why add unnecessary weight?

This boat hull was from about 10 years back when brushed motors were prime, and the hull is somewhat thin ABS. You can flex the V of the hull with a little bit of hand pressure. I wanted to lay carbon sheet inside, but someone gave me a better idea...

What I'm going to do instead is drill a hole in the top of the hull, use a funnel and pour a 2-part expanding foam mixture into the hull. The expanding foam is very strong when it cures. Then I am going to lay a small strip of carbon on top and re-drill motor mount holes. This will make it brushless worthy and strong without the flex.

Please make pictures as you're going to put exp.foam in a ABS hull.

We shure could use a good laugh.

i bet it looks like my neighbors butt.

Really?

I did not realize the foam created a bunch of pressure when it cured. I have two bottles, you mix 50:50 proportions together, and the foam slowly expands. It did not look to me like it would actually inflate a hull, but I better test this on something first. I will pour some into a water bottle and put the cap back up. And put it a little ways away.

Guys, this foam doesn't inflate things.

It swells up, and oozes out of the relief hole. It's a go.

youv'e got to watch out for heat build up too.

Hi Matt.
I think the guys are being a little rough on you, but sincere. I have seen the foam blow sheet rock off walls. [:@]
You are doing the correct thing. Test it so you know what to expect. If it is possible, drill 1/2" holes in the upper deck at both ends of your hull and in the middle. More holes don't hurt. This will allow the foam to run and expand all the way to both ends, leaving very little air pockets, or soft spots. If it looks like there is any heat building up, put a cold wet towel on the outside of the hull to protect the ABS. You can buy special ABS cement, to plug your holes, after you cut the excess foam away. The hardware store sells ABS cement in the plumbing dept. Use a scrap piece of ABS, in the hole and make sure all the paint is sanded away first. Have fun and good luck.
ps
Remember, this could be a place to trap water and never dry out, making your hull very heavy.[]

There are some 2 part foam that does not re-expand. Futher testing on what you want to use may save some headaches later. Seems you have already "test" the 2 part foam. Now take what you have and place it in the sun and let it get warm. Better yet, put that in an atic (if you have one) and let it sit a day or two. The outcome may surprise you. I had a 6' deep v sitting in the atic for a summer. Went to move it one day and the front was split wide open. I know for a fact that 2 part foam was sitting as it was for over 10 years before I got the boat. Stupid me put the boat were it got very hot during the summer.