Zodiac Mk2C GT SIB - Thrust Board Movement

[mijos]

I noticed that my 1984 Zodiac Mk2C thrust floorboard seems to have moved 5mm towards the bow, causing some rippling on port side in the upper and lower hypalon strip/sandwich flaps that attach it to the side tube thrust patches. This only occurs when the 3 aluminium floorboards are inserted. I can't see that this really matters as surely the motor thrust is transferred forwards through to the bow floorboards. (Newer one-piece inflatable floors do this anyway?) Has anyone experienced this, and what remedy can be suggested.

I have tried re-gluing the flaps using epoxy, but there is still some give between where the side of the board ends and the side tubes. Fitting the floor boards tends to push the whole assemble 20mm forwards (as boards are longer than gap available). This was always so as it appears to be a design feature. Perhaps when the boat was new the tubes would stretch, but now it is old the board chooses to move instead.

Boat is rarely used, carries a 20hp mercury

[spartacus]

A 1984 UK spec Zodiac will be PVC. Over time, inflating and assembly take their toll on the material, especially around the seams, transom joints, etc. All you can do is clean off damaged area with acetone, lightly sand and re-glue with 2-part glue from Poly-marine. Its just showing its age.

[m chappelow]

how about making a bow board to help shove it back ,

[mijos]

spartacus - thanks very much for advice.

Boat is actually April 1985 - I seem to recall I was told it was Hypalon from serial number - which affects the type of polymarine glue you can use.

Floor boards are longer than gap available, which puts the glued joint under considerable strain when they are inserted, effectively stretching the tubes.

I think I might try doubling up on the thickness of the flap joint.

If that doesn't work, a longer bow board might be the answer.

[mijos]

m chappelow - I see from another post on elephant trunk drains, that you re-boarded a zodiac. It doesn't look an easy job - having detached flaps on one side, they've shrunk a bit and will need careful placing to get the right set-up befre inserting the floor. I like the RNLI bottle jack idea.

[m chappelow]

Originally Posted by mijos

m chappelow - I see from another post on elephant trunk drains, that you re-boarded a zodiac. It doesn't look an easy job - having detached flaps on one side, they've shrunk a bit and will need careful placing to get the right set-up befre inserting the floor. I like the RNLI bottle jack idea.

you will need a one piece board to go from the transom up to where the thrust board was ,,,do away with it altogether .or to where the bow starts to rise and then you can either make another bow board to go from the main board right up into the top corner of the bow or make a smaller triangular bow board to go right into the bow end and then use bottle screws to make it ridgid ,,,,as long as you round off the edges of the boards where they touch the rubber you shouldent have any problems ,, as you said ,,in replacing the thrust board with a one piece the engine thrust is distributed into the bow,, and the inflatable keels upward thrust is just about distrubuted throughout the one piece floorboard unlike the original thrust board system where it is nearly all taken on the fabric flaps,,only problem with either system is its best to leave the boat inflated ,,,well ,easier .,,,instead of bottle screws you could make a couple of pieces of wood slotted or forked at each end, to fit the main board and bow board ,locate them at an angle then tap them tight into position .,,good luck mart