How to handle a bulkhead former for a POB model

[glennb17]

Hello ship modellers,

I opened up a plank-on-bulkhead kit and set out to start with the bulkheads. The first thing I noticed was that the bulkhead former, the sheet that runs down the middle of the ship to hold the bulkheads, was slightly warped. It was cupped a bit lengthwise. I wouldn't expect that from plywood, but it is what it is.

Any advice on how to handle this? I have some ideas but would like to hear from the experts.

Thanks,
Glenn

 

[AndyA]

Pictures please!

 

[Corsair]

Many (not all) of the kits have you put on the bulkheads on the centerpiece. You can have a bow in it to port or starboard but then they have you put on a false deck where the bulkheads poke up through the deck and this will usually straighten out the bow.

 

[glennb17]

Pictures please!

Hi Andy, I tried some pictures but it didn't show well. Anyway, when you lay it flat, it is a bit cupped with a high spot closer to the bow than aft. I think I can get all my bulkheads on perpendicular to the bulkhead former, but the 1st and last bulkheads might not be parallel.

 

[Uwek]

You can try to install some filler pieces between the false keel (former) and the bulkheads - with this you can force the parts to keep a rectangle angle



If the part is to much warped, you should contact the manufacturer to get a spare part.

Which ship model kit is it?

 

[AndyA]

Glenn:
Uwek's fix looks good. The key is to make sure everything is straight and square before proceeding. If not, all further work will be compromised. Have fun!

 

[glennb17]

I'm building Model Shipway's Syren. I've built other POBs, but this bulkhead former was pretty cupped. I used a lot of wooden blocks to true the bulkheads to the former and it seems it got rid of most of it. I'll try to add some more material closer to outboard, but not really seeing much of a twist anymore.
I wasn't sure if anyone had a trick like soaking the plywood and weighting down or what have you.
Thanks guys.

 

[danielsje]

In my experience soaking and weighing is of little value with plywood. The best option, as previously mentioned above, is to attach the bulkheads with each individually square to the false keel, then align the bulkheads with blocks which will force the false keel to straighten.

 

[JohnK]

Uwek, you have brought a very intersting booklet to my/our attention. I have just read through most of it and some parts are basic but most is very interesting. It has taught me some good tips and procedure which I will try to incorporate into my new build adventure whilst fending off the Pirates, high seas, and sunning myself in the Caribbean (I should be so lucky) with the Black Pearl.
The parrots are already flying.
Thank you.
AHH Jim lad

JohnK

 

[stephenleon]

To address a warped bulkhead former for a plank-on-bulkhead (POB) model, consider soaking the plywood sheet in warm water to soften it, then gently bend it back into shape using clamps or weights to hold it flat until it dries. Alternatively, apply heat with a hairdryer or steam to make it more pliable for reshaping. Once corrected, ensure the former is securely attached to the model's keel and bulkheads, using glue or fasteners as needed for stability.

 

[glennb17]

In the end, I found that installing the bulkheads and clamping in big enough squared blocks tightly against the former and bulkhead connection did it. The blocks were carefully checked for right angles and were clamped in with a fair amount of force and tons of glue. The method Uwe suggested is excellent for alignment as well, especially when you have slop in the connection between bulkhead and former. I just though clamping in some straight surfaces would alleviate the pucker in the former and got lucky. It also absorbed all the play in the angles between former and bulkheads and everything trued up.

Thanks everyone for the kind contributions, I learned a lot through this happy accident. This forum is always so helpful!!