C-Forum

need to find plastic welder in Alabama to repair hull. thanks D-Caption

IF it is Zephyr there is a special process that makes very strong repairs rather than welding

Try auto body shop if it is plastic this what they use to fix plastic bumpers

what boat... model and material?

They require different fixes, even matters if HDPE is linear or crosslinked.

Oh man, I misread the title of this post as "Cracked Hull in Hairline."

Maybe I have Decker's Creek on the brain?

A Craiged hull near the hairline can be Smerder !

It is a bell Ocoee three years old, crack is inside on the bottom. Before YALL START beatin me up for buying thr ..other... brand... tell Louie and some of his friends to get those Daggers out of their sheds and basements and sell one to folks who want to paddle them. They are more rare than hens teeth. I,ll take eddy hops advice and paddle this boat till I wear the skin off the bottom. thanks D-Caption

An inside crack can be fixed, not by welding, but by scraping off the vinyl and then patching with 3 layers of Kevlar, largest layer first, and epoxy. The Kevlar should be bias cut so that twice as many fibers cross the crack, diagonally.

There are also ways to patch with ABS sheet and liquid ABS, but I haven't used them. Others here may provide methods.

I think it was Jim Michaud I heard this from - patch the inside with raft material. You need something that will have strength in tension. ABS cement and ABS sheet may may work in that application as well - but I wouldn't put a lot of stock in ABS paste alone. Someone else here did mention using dryer sheets as a reinforcement (they are fiberglass I believe) with ABS paste, that might work, too.

I've had great success patching inside cracks with raft vinyl. Just be sure to drill both ends of the crack to stop the crack from cracking further. The advantage of raft vinyl is that it flexes, thus you don't have to deal with the patch cracking.

If the crack goes down into the ABS, I've stuffed JB Weld in the crack so when you apply the patch no vinylbond goes down into it. I've heard bad things about vinylbond melting ABS, though haven't experienced it myself.

Another fix I would consider that would have even more strength to it would be Rec Repair. I have a Rec Repair patch I put on the outside of my canoe that has taken a beating over the last 5 months and is still totally adhered to the boat. And it's on the chine where I'm frequently scraping up against rocks. It is self adhesive and easy to apply. One tip to using it is to clean the area really well before applying the patch and after applying the patch, heat the heck out of it with a hair dryer.

I'm a big fan of JBWeld and that RecRepair stuff seems great but I haven't used mine yet.
I've repaired some wicked cracks with JBWeld and nylon mesh which have lasted for years with no signs of weakening.
Straight JBWeld works great on gouges and nose dents. I just use a putty knife to apply and if done properly, no sanding is required.

I particularly like JB Weld for exterior gouges and dents because the metal in it makes it wear away very slowly and naturally from contact with rocks. It doesn't loosen and fall off in chunks. Instead, it gets sanded by the rocks. Of course your boat ends up looking like an appaloosa, but as long as the hull is holding up, who cares.

I think it was Jim Michaud I heard this from - patch the inside with raft material. You need something that will have strength in tension. ABS cement and ABS sheet may may work in that application as well - but I wouldn't put a lot of stock in ABS paste alone. Someone else here did mention using dryer sheets as a reinforcement (they are fiberglass I believe) with ABS paste, that might work, too

One day I beat the living snot out of my Caption running a steep creek in low water. The outside was OK but the inside was badly cracked. I patched the cracks up with raft scraps that I dug out of Aire's dumpster. I used plain old Vynabond to stick it down with. I've since gotten many more cracks from creeking. Last fall I removed the saddle and turned it around. Before glueing the saddle back down I laid patches over most of the bottom, sealing up all the rest of the cracks.

I use to use Kevlar but after awhile the boat would crack again along the edges of the Kevlar patch no matter how careful I was. I've yet to have any problem with the raft material. On the next canoe that I buy I'm going to reinforce the inside before I ever paddle it.

I also use the heavy duty raft floor stuff to make my own D-ring patches.

Jim

Hmmm.... You shouldn't get cracks around the edges of a Kevlar patch if you use concentric layers, the largest laid on first. Well, I wouldn't say "never" but hardly ever. The trick is avoiding a sudden transition in stiffness. I guess raft material is so flexible as to avoid creating transition zones, but does it keep the cracks from "working" under the patches?

Like Jim Michaud, but I've been using plain old clear sheet vinyl with vinabond. If you de-stress the crack first they do not spread. Easy enough to monitor with clear vinyl on top !

No worries about exposed ABS, just glue it on as a contact cement, not wet.