Bombard Aerotec transom repair

piotr · 21 September 2015, 08:10

Hi,

I need your opinion. The transom of my Aerotec is coming loose (see pics). Does this mean a totall reglue or just a repair of the particular spots ? Transom feels solid.

Fenlander · 21 September 2015, 08:26

A total re-glue is a massive job... mainly getting all those overlapping sections off without damage and then cleaning it up to a proper standard. And you'll need warmth plus low humidity to use the new glue.

Can you continue pulling this apart further than where it stops at the moment. Have you also looked very carefully at all the other parts of the transom and the floor-to-tube glued seams.

I use a soft plastic scraper to see if I can prise the seams apart.

Yes it is possible to make a strong repair to the problems you've found if that really is the extent of the failure.

Perhaps a professional who was charging you for the work might not be happy just doing sections but my belief is it's fine for a DIY job... you will have to keep an eye on all the seams from now on though.

Have you seen my thread from this summer where I carried out even more complex localised repairs to the old Aerotec I owned...

http://www.rib.net/forum/f50/aerotec...ice-68545.html

Despite some choppy water testing at speed since then every repair has stayed strong.

office888 · 21 September 2015, 12:24

Quote:

Originally Posted by piotr

Hi,

I need your opinion. The transom of my Aerotec is coming loose (see pics). Does this mean a totall reglue or just a repair of the particular spots ? Transom feels solid.

What year is the boat?

Max... · 21 September 2015, 14:15

Some say if one part starts peeling then the rest will follow but this may not always be so. The first pictured part will obviously need proper gluing with two part glue but if you have a tiny section peeling (as on the second picture) or even slightly open just lift it up slightly, clean inside and then squeeze in a dab of black Sikaflex in, then push down the PVC to squeeze out the excess (don't go mad). This will in many cases be all that is required to seal it and stop the water getting in further and causing more issues/peeling.

piotr · 21 September 2015, 14:27

Quote:

Originally Posted by office888

What year is the boat?

2005. Ps: no water coming in, i can feel no movement in the transom.

office888 · 21 September 2015, 15:05

Quote:

Originally Posted by piotr

2005. Ps: no water coming in, i can feel no movement in the transom.

In my unprofessional opinion, you could probably touch it up with PVC glue and get another 2-5 years out of it.

I will warn you though, when you go to reglue, the MEK used during the cleaning process and the solvent fumes given off by the glue will unglue more material. I will also recommend using some blocks and vice clamps to apply a lot of pressure to the material during curing...allow curing for 2-3 days.

I would budget a complete reglue within the next 1 to 5 years though.

piotr · 21 September 2015, 15:07

Thanks for the reply Richard. Appreciate it.

office888 · 21 September 2015, 15:26

Quote:

Originally Posted by piotr

Thanks for the reply Richard. Appreciate it.

Not a problem at all! Just make sure to scrub with MEK heavily to remove the old glue first...

It's not difficult or expensive work, just time consuming.

piotr · 16 November 2015, 12:20

I've had an offer from a boatshop to reglue the transom for 450,- euro's (320 pounds). I doubt if the boat is worth this investment.

I've inflated the boat this weekend and carefully checked the transom, there is no movement. However, the part in the first picture came loose from top to bottom.

As you can see in the picture the material is quite thin, is this really what is holding the transom in place ?

I will see if i can get the right conditions for glueing (temp/hum) and attempt the repair myself. Has any Aerotec owner ever attempted to reinforce the construction where the transom meets the tubes ?

Fenlander · 16 November 2015, 12:49

Yes the material is thin and yes it is all that holds the transom on.

There is no need to reinforce the transom... just repair where you see it failing... as per the methods mentioned previously.

£320 is a lot to do the transom... and you will probably find the floor-tube seam will go the same in places soon too so it's not as if that £320 will guarantee another failure free 5yrs.

piotr · 18 January 2016, 10:55

Quote:

Originally Posted by office888

In my unprofessional opinion, you could probably touch it up with PVC glue and get another 2-5 years out of it.

I will warn you though, when you go to reglue, the MEK used during the cleaning process and the solvent fumes given off by the glue will unglue more material. I will also recommend using some blocks and vice clamps to apply a lot of pressure to the material during curing...allow curing for 2-3 days.

I would budget a complete reglue within the next 1 to 5 years though.

I'm going to attempt the repair as soon as conditions allow.

From what I've collected from various posts, these are the steps:

- Sand transom wood and clean with MEK
- Remove old glue from pvc with MEK
- Prepare transom-wood with single part hypalon glue (let it cure ?)
- Wait for optimal conditions (temp/hum)
- glue transom and let cure in clamps for 3 days

Correct ?

office888 · 18 January 2016, 12:18

Quote:

Originally Posted by piotr

I'm going to attempt the repair as soon as conditions allow.

From what I've collected from various posts, these are the steps:

- Sand transom wood and clean with MEK
- Remove old glue from pvc with MEK
- Prepare transom-wood with single part hypalon glue (let it cure ?)
- Wait for optimal conditions (temp/hum)
- glue transom and let cure in clamps for 3 days

Correct ?

Sounds like a plan.

I prefer diluted PVC glue for wood priming. Thin PVC glue 50% with MEK, then apply. Word of caution though, the mixture is EXTREMELY watery...about the consistency of vegetable oil. Do 3 coats with a 5 min flash in between, and let it cure. This will serve to soak in to the grain structure of the wood. The first 2 coats will almost completely "disappear", then the third coat will self-level. Then when you bond stuff, you're bonding to PVC glue that is well-chained in to the wood, rather than a hilly, porous surface where you would have gaps of glue that are bonded to voids in the wood (bonded to nothing actually!).

The material for the transom is a heavy coating of PVC with a 1200 decitex polyester weave. It is a little heavier than the usual PVC that the factory uses for most PVC stuff. I can be a little more difficult to bend and flex without wrinkles.

While you're gluing and have glue available, I would recommend inspecting all glued surfaces. If you can lift an edge and peel a surface back with only a few kg of force, the piece should be reglued.

I would suggest purchasing a minimum of 0.5L glue , 4L of MEK for this job.

piotr · 18 January 2016, 12:21

Quote:

Originally Posted by office888

Sounds like a plan.

The material for the transom is a heavy coating of PVC with a 1200 decitex polyester weave. It is a little heavier than the usual PVC that the factory uses for most PVC stuff. I can be a little more difficult to bend and flex without wrinkles.

See the pictures, to me it looks/feels like thin material. The parts in the picture are the only places where it has come loose, rest of the transom is solid.

office888 · 18 January 2016, 12:39

Quote:

Originally Posted by piotr

See the pictures, to me it looks/feels like thin material. The parts in the picture are the only places where it has come loose, rest of the transom is solid.

The difference between the standard PVC and the "heavy duty" PVC that Zodiac uses is almost imperceptible to most. It is only a difference of a few grams per centimeter.

piotr · 22 January 2016, 13:38

Going to order the glue this weekend, I guess Polymarine is ok ?
Just to be sure, the how-to on Polymarine website says "pvc glue does not stick to wood": Zodiac Dinghy Transom Repair | Polymarine Paints, Adhesives, Parts & Accessories

So, should I follow their advice or yours ;-)

office888 · 22 January 2016, 13:51

Quote:

Originally Posted by piotr

Going to order the glue this weekend, I guess Polymarine is ok ?
Just to be sure, the how-to on Polymarine website says "pvc glue does not stick to wood": Zodiac Dinghy Transom Repair | Polymarine Paints, Adhesives, Parts & Accessories

So, should I follow their advice or yours ;-)

Your choice! I use Bostik Vinycol 1520 which is probably a completely different formulation... I don't like Polymarine, it is too thick in my opinion.

Fenlander · 22 January 2016, 14:57

I'm going to chuck in a practical rather than by the book idea...

I guess the transom will have already been primed when the boat was made?? Assuming so why not just give the wood a very light fast wipe with cleaning solvent (MEK or whatever) so that the existing glue priming layer is retained and then glue to that??

office888 · 22 January 2016, 15:13

Quote:

Originally Posted by Fenlander

I'm going to chuck in a practical rather than by the book idea...

I guess the transom will have already been primed when the boat was made?? Assuming so why not just give the wood a very light fast wipe with cleaning solvent (MEK or whatever) so that the existing glue priming layer is retained and then glue to that??

The primer used at the factory has a maximum coating interval of 0.5 hr - 8 hr.

Fenlander · 22 January 2016, 15:31

OK understood... but might the MEK tend to re-activate it sufficient for a 2-3 year DIY repair?

office888 · 22 January 2016, 15:38

Quote:

Originally Posted by Fenlander

OK understood... but might the MEK tend to re-activate it sufficient for a 2-3 year DIY repair?

My understanding of the factory primer is that it chemically crosslinks with the glue as it is applied.