Thread: Tricky fix

Richard,

Fixing it is one thing, but one must ask why it cracked? Did the glue fail, and if so was it because of inadequate preparation of the joint?

If that was the case, then more glue won't help.

Having said that, try masking off the area to within a few mm of the crack (just to make cleanup easier) and then go to a chemist and buy a syringe with a needle of suitable size. A bit oversize is ok.

Prise the crack apart as far as you can, and liberally squirt epoxy in it.

Clamp/weight the crack closed.

Hang around for an hour or so cleaning up the mess as it runs out.

If all goes well, you'll have a nice new join for someone to break off next time you go out.

Cheers,

P

No show of opening it enough to get anything in there mate - it's only cracked out past the inwale - over the inwale, it's good and solid. It broke because people keep lifting it there - from now on, it's grab onto the inwales to lift or Cap'n Bligh gets cranky ... and yes, there's possibly a dry joint as well, it being endgrain (and your flamin' gaboon to boot ), but it was well primed and a lot of poxy was pushed out. But a 6mm wide joint? Doesn't take much to upset it ... and yes, it's as per the plans.

Richard

Those little "Dremel" clone hobby tools are great for opening up spots like that to re-do the epoxy. I picked up a RYOBI very cheap in a Cash Coverters. They are very controllable and there is a wide range of different tips.
(I need some new tips after trying my hand unsuccessfully at Hebel block sculpture. )

Originally Posted by onthebeachalone

....................(I need some new tips after trying my hand unsuccessfully at Hebel block sculpture. )

OTBA,
Tip: use diamond or TCT grit burrs when working aerated concrete.

Hows that for a new tip.

Mick

Maybe make up some SS plates just about 2-3mm think and just a little smaller all the way round but the same shap as the gusset. Polish them up and round the top corner all way round, then scew them on through the lot. Put a liberal bit of Sika under it to stop water getting into the screw holes This would mean that bugger lugs could lift it all day there and it wont crack! and look nice with bit of bright work?
Thats what I would do, mainly becuase it would never need doing again.......I like that.
Let us know how you go
Scotty

I'll lift her off the trailer and have a go this weekend - listen for howls of anguish.

Richard

May be easiest to fit a hanging gussett to the transom so that it supports the cracked gussett, then refasten with screws and glue. Don't need to disturb any paint to do this, just adding more strength to the boat.

Hi Daddles - I suspect the problem might be in quite another plane from what you are thinking about. Can you take some better pics including from above and below?

I suspect the inwale being pulled up might simply be levering the bow knee around.

Maybe the knee just doesn't have enough salient gluing area to the top of the transom for the loads being put on it.

Also - is that supposed to be a balance or standing lug rig. I can see some improvements that will make the boat sail much better.

Originally Posted by Boatmik

Hi Daddles - I suspect the problem might be in quite another plane from what you are thinking about. Can you take some better pics including from above and below?

I suspect the inwale being pulled up might simply be levering the bow knee around.

Maybe the knee just doesn't have enough salient gluing area to the top of the transom for the loads being put on it.

KNEE! Dats da word I was looking for

Nah, it's just the knee that's come adrift and the problem owes more to edge gluing a thin bit of ply than anything else, then having people lift the boat from it.

Also - is that supposed to be a balance or standing lug rig. I can see some improvements that will make the boat sail much better.

Gotcha This is that wee boatie that you helped me set up
Actually, that photo was probably one of the first ones taken and I did set her up wrong the first time.

Here's another of her first day sailing (in a flat calm). The bruck knee is the one by my left elbow as it happens.



This is the boat I'm suggesting for the PDR committee boat at Goolwa Mik She'd have to appropriate because she's shorter than a PD (guess I'd better put my entry in). Be a good time to learn how to sail her too, something I've been remarkably slack about (and lucky in that all my trips have been in light winds). We can find tune the setting up then.

Richard

I'll have a good look at it tomorrow (that being saturday - she's still upside down on the trailer). I doubt I'll be able to open the crack up enough to do Midge's fix however, I do have a dremel so using a thin cutter and Midge's syringe, I should be able to do something ... though a good coat of paint and stern warnings about lifting from it spring to mind. I should scrape the paint off underneath and put a decent fillet in under it, but that's too much like hard work at this stage. I'll save that sort of silliness for after I've been able to give Mik a good look at it (Goolwa I hope).

Richard

Howdy Richard,

it will be nice to have Redback there as a commitee boat - if you try to sail her against the PDRs you be whopped!!!

But that doesn't mean you won't be having fun!!!

I'll be spending part of my time on the Duck Flat Stand and part racing the PDRs, organising the races and getting people to try the boats as well.

We will have around 5 boats for people to borrow during non racing periods.

MIK

I've been thinking about the break - it is a typical problem of thin plywood knees. you either need a bracing piece across the throat of the knee or built it up from the underside with more layers of ply for greater stiffness and bonding area.

I never specify thin ply knees of this type because they are such good handles so will be subject to high loads - and the flexibility means the load is concentrated on the closest bit of join to the hand rather than distributed over the whole knee.

If you pick the boat up by the knee and the crack widens or narrows ... theres your problem - and fixing the crack won't fix the problem.

Also if the knee lack rigidity and is flexed when the boat is pulled up it can change the angle of the side of the boat to the bottom and the transom/side join will break

Originally Posted by Boatmik

it will be nice to have Redback there as a commitee boat - if you try to sail her against the PDRs you be whopped!!!

I know this, that's why I'm fitting Chardonnay glass holders ... and a brass swivel gun

Richard

DUCK