Hi All,

My reason for this post, is as follows:

A post appeared for the SOTS, ref:"Hull Profile" by NMBROOK (Nigel)and it drew people`s attention to a small error in the hull shape caused by rib shape defect.
This problem will be easily cured by a couple of methods dependent on what stage of the build you are at.

It was while investigating the above issue that I found an error in my own build. Rib #26 was out of line on the starboard side by a significant amount.

My first thought was "Strip down time", but as I had planked up to issue 27 that idea filled me with horrors .

At this point NIGEL came to the rescue with the following information and idea on how to fix the problem.

First: Gauge how big an issue I was dealing with.

The good side (Port)Pic 1



The bad side (Starboard)
Note the gap between rib #22 and the ruler.Pic 2



Next:Mark where the rib needed to end up.
I placed a ruler along the outer edge of the top plate of the gallery and marked where it crossed rib #26 on both sides.

PORT. Pic 3


Starboard: note the line of the ruler and the second mark on the rib which is the point that should be in line with the ruler.Pic 4



So that`s the issue, now the solution:

I moved the ruler up from the deck level, whilst against the ribs until things went out of line and marked that point on the defective rib. I also at this point put two lines top to bottom as guide lines for the reinforcement rods that are to be installed. Sorry pics a bit fuzzy - got to close for camera . Pic 5



It is at this point the knife gets a brand new shining blade and I very carefully removed the offending rib.Pic 6



The next job was a bit testing as i had to make a miniature wedge to fit between the rib parts. This is to tilt the rib top inwards and maintain the correct height at the top of the rib.

It is small:
And out of focus again . Pic 7



The wedge was superglued to the lower half of the rib.
I am using 2mm brass tube for reinforcement so drilled 2.5mm holes in both halves of the rib to allow the adhesive a bit of grab space.
I have used brass tube for two main reasons:

1: Allows the adhesive to flow inside so you dont just push it back out of the holes and

2: Easier to bend very slightly to obtain correct alignment with holes in upper part of rib.


Before the parts see any adhesive I checked that everything would fit to give the desired cure to the problem.Pic 8



Please note that the ruler is not exactly on the mark but very close. Final adjustment to come.

It is critical at this point to realise that the rib also needs to be kept in the correct vertical plane in respect of the other ribs, so I cut a 34mm balsa wood spacer.Pic 9



Then came the second dry test fitting.Pic 10



As a final check, were the deck support extensions on the inside of the rib level? Pic 11



It was close, but final fitting will get it better.

Adhesive next, a two part epoxy with 5 minute adjustment time.Pic 12



Next fix the pins into upper part of rib and glue.Pic 13



Not shown, but clean of any glue that comes out as can put alignment out during final fit.

To give a very small amount of adjustment, before the pins set firm, i went for the final fit/ adjustment and clamping and left to set.Pic 14



My apologies if this article is a bit long, but did not want to miss out any important details.

Lastly many thanks to Nigel (NMBROOK) for his invaluable advice on how to deal with this sort of problem.


Regards
delboy271155
(Derek)

Delboy,

A good post of how to resolve your problem, though its wrong to suggest that this is a problem for everyone, as it is not.

It could well be as a result of how the frame was initially seated or indeed a rogue part.

Good to see that you have managed to correct this..

The main is that this has been caught before it was too late, and your highlight also show's the novice how you set about putting it right.

Well done!

As a Novice, I would not have re-enforced the cut-off with bars. Using Brass rods is an exellent idea. Its like using re-bar in a construction of a tower.

Great tip for a repair job when the wind decide to take your ship for a sail onto the carpet.