First bit of damage to the new boat - advice please!

Mattster · 13 August 2021, 15:29

OK so I stuffed up on Wednesday when loading the boat back into my car. I ended up dragging it for a very short distance on tarmac, and when I got back and unloaded it was evident that the corner of a fold had borne the brunt of this, and not only worn a hole through the boat bag but quite badly scuffed a small section of the tube:

The location is forward, on the underside of the tube:

Close up:

Part of the damage is on the double layer seam, but part is only single layer. There is some depth to the cut there, but it has not gone all the way through. As far as I know, the boat still holds pressure, but since I can only get it to 1 psi at the moment (pump issue in different thread!) I don't know.

I assume this needs a protective patch before I go out again. Does that sound right? Does being on a seam make things harder? Would you trust the glue that came with the boat? (less than 3 weeks old, so probably still "good"). Should I have the boat inflated as I perform the repair?

thanks!

willk · 13 August 2021, 15:51

From a leaking air POV, that's a bad place to try for a patch, being on a join. Luckily, it's not leaking. Personally, I'd clean the area carefully with a cloth damp with thinners (not wetting the glue at the join) and apply a pool of urethane adhesive around the entire scuff. You'll have to deflate the tube and build up a "wall" of tape around the flattened area. Once that goes off you could consider sticking a patch over the entire thing, for cosmetic reasons and some extra protection against abrasion.

All IMHO. I don't think it's a serious scuff, unless it's more than a mill deep.

Fenlander · 13 August 2021, 16:06

I know what Willk means but even if that were a leaking pinhole as the leak would not be from a failing seam it's an easy repair. I am nervous going against any of Willk's advice given his experience with sibs and ribs but I'd put on a conventional patch and not give it a second thought.

Don't worry the patch would be bridging three different material heights. It will roll down and cling to them all OK. See this overlaying of material I did on a lift handle where the top material nicely follows the contours of the differing layers underneath.

You have learned the hard way but I'd not ever drag a bagged SIB over anything, always lift. They are easily snagged, for example, on the hatchback catch if pushed/dragged into the back of a car.

Mattster · 13 August 2021, 16:22

Thanks guys.
Update on the tear is that it is leaking at full pressure - see this vid.

How will this change my approach?

Pump is working again for some reason, which is worse than just being completely kaput and getting a swap - really don't want a temperamental unit!

willk · 13 August 2021, 16:39

Quote:

Originally Posted by Fenlander

I am nervous going against any of Willk's advice given his experience with sibs and ribs...

No please, be my guest!

Just spotted the OP's update - it's a patch for sure!

Mattster · 13 August 2021, 16:46

THanks willk. Thinking I might follow your earlier advise and use something like aquaseal first (is this the same as stormsure, do you know? this seems more quickly available on Amazon for some reason). Do you think filling the hole before patching is worth the extra effort?

I've been reading the repair procedure on the Polymarine site, but it is still not clear to me whether or not the boat should be inflated - I'm wondering how flat it will be defflated, as this has been on a fold, and also whether there is stretch to consider when adding the patch?

I think I will go ahead and order the bits from Polymarine anyway - no great loss, because I needed glue for some mounts I am planning on adding anyway.

Fenlander · 13 August 2021, 16:47

I have two repairs on my Aerotec. Both on the HP floor which pumps to 0.8bar.

One is near impossible to get a patch on without a bit of deconstruction... so I've used a product like the one Willk links. I factored in that it's in a position with no rubbing or abrasion so a patch seemed less crucial.

The other is a simple pinprick like yours on the bottom of the HP floor which does get rubbed so I patched in the conventional way 3yrs ago as in the attached image and it's still as good as the day it went on.

Fenlander · 13 August 2021, 16:48

Do it deflated... the patch will stretch with the tubes once the glue has cured.

Fenlander · 13 August 2021, 16:50

>>>Pump is working again for some reason, which is worse than just being completely kaput and getting a swap - really don't want a temperamental unit!

I'm 100% with that... just keep waiting for it to happen again.

spartacus · 13 August 2021, 16:51

Patch it. Once you've sanded it, you'll have a clearer idea of what you're dealing with. Follow the gluing instructions to the letter on Polymarine's site for PVC, mask off, degrease, sand the back of a circular patch, and leave for 24 hours before inflating to pressure.

Mattster · 13 August 2021, 16:53

Thanks all, kit ordered from Polymarine and I'll get some aquasure type stuff as well.
So do I need to clean up the tear before proceeding, or just go for it? I'm not talking about degrease/solvent etc, which I will obviously do, but the bits of fibre hanging off the cuts.

Fenlander · 13 August 2021, 16:57

Use MEK or Polymarine's own 2903 as a solvent, PVC doesn't need sanding... it's not part of the Polymarine instructions.

Fenlander · 13 August 2021, 16:58

My concern with Aquasure is... will the PVC patch bond to it or could it actually be where the patch adhesion starts to fail over time?

Mattster · 13 August 2021, 17:09

Quote:

Originally Posted by Fenlander

>>>Pump is working again for some reason, which is worse than just being completely kaput and getting a swap - really don't want a temperamental unit!

I'm 100% with that... just keep waiting for it to happen again.

I'm going to pop up to Force 4 tomorrow and explain the situation, hopefully they'll swap it, although I think I am in for a week's wait at least because they don't have it in stock.

Mattster · 13 August 2021, 17:11

Quote:

Originally Posted by Fenlander

Use MEK or Polymarine's own 2903 as a solvent, PVC doesn't need sanding... it's not part of the Polymarine instructions.

Thanks, will do. I ordered the complete kit from PM, not that I particularly wanted to since I have a bit of patch material and plenty of old paint brushes, but they are out of stock of "glue only" and so seemingly is everywhere else!

Make some attempt to cut the fibres back or just go for it you reckon?

Fenlander · 13 August 2021, 17:29

You could trim the fibres with a new blade on a Stanley knife or scalpel.... I probably would.

jwalker · 13 August 2021, 18:43

Trim the hairy off with scissors. The PM kit is the way to go because the adhesive will come with a curing agent but the quick repair kit won't.
Don't sand the area and when you apply the adhesive wipe it on against the edge of the tube fabric to give a slight ramp. Don't use the PM method here. Apply three light coats of adhesive to both the patch and the tube, have the tube deflated so no air can leak into your patch when applying it, when it's touch dry wipe the adhesive up to the ramp and the equivalent area of the patch with some MEK. Apply the patch towards the ramp but keep it folded slightly and rub it down hard with a piece of wood or similar as you advance. Doing this will ensure you get no air bubbles under the patch and you can also press is down hard at the ramp so as not to bridge the slight step. When that's done, apply more MEK to the rest of the patch and tube and repeat to fix down the rest of the repair.

NOTE! Once the two MEK'd surfaces come together they will immediately glue down like you won't believe, don't get placing the patch wrong, you only get one go! Well, not quite, you can flood the joint with MEK and tease it apart if you have to but it's not recommended.

PS, your boat has welded seams, you don't need to worry about the MEK solvent affecting the original joint.

Mattster · 13 August 2021, 20:00

Thanks JW for the detailed instructions.
Just to clarify, the difference between this method and the PM one is that you apply 3 coats of adhesive, wait until touch dry (not tacky) and then reactivate with MEK at the moment of application? I have the PM solvent coming with the kit which says it "contains" MEK but doesn't specify that that is all it contains. Suitable? I assume prep using the MEK before adhesive still applies?
thanks!

jwalker · 14 August 2021, 00:40

Yep, prep as usual a couple of coats of MEK to open up the PVC. Using the 'tacky' method it's a bit hit and miss - how tacky is tacky - and if you place part of the joint a little out of line it's too late to move it. By using the reactivation method you can place your patch then lift a bit of it to apply the MEK so you work only enough that you can deal with comfortably then move along.

If the PM solvent is more than just MEK I've no idea what else is in it. It used to be plain MEK.

Mattster · 14 August 2021, 09:37

Quote:

Originally Posted by jwalker

If the PM solvent is more than just MEK I've no idea what else is in it. It used to be plain MEK.

Thanks again JW. I'm sure you're right, it is marketed as "2903 Solvent/cleaner" but it does also state that it is suitable for reactivating adhesive so it probably just is pure MEK. Looking forward to breaking my first repair cherry and giving this a go!