Bulkheads from solid wood

[Burroak]

Has anyone ever made their own bulkheads for a model ship? I have a Charles Morgan kit by Model shipways but I would like to make as much as I can from scratch. I was wondering if solid wood would warp more than plywood?

[TBlack]

Greg,

I've used both without ant adverse effects. If the bulkheads are of solid wood, and you put supporting blocks between the bulkheads and then plank the hull, there would

be little room for the bulkheads to get out of alignment. Plywood would be more stable, but may not be necessary.

Tom

[catopower]

I have used both single ply sheet wood as well as plywood to scratch build the hull. If you have bulkhead extensions, i.e. timberheads, then I'd stick with plywood, you'll have fewer problems with breakage. Otherwise, single ply sheet wood should be fine.

[allanyed]

Clare makes an important point about the top timbers.   AIRCRAFT plywood is the best solution, albeit very expensive.  The moulded dimension of the top timbers (extensions) is sometimes much too large on , but with aircraft play it really is no issue at all to have them to scale.  Good birch veneer plywood works well and costs a lot less but as with most things, you get what you pay for.  If the scale is in the 1:64 or 1:96 range I would bite the bullet and get the aircraft plywood.

 

Do your plans have the bulkhead drawings?  If not, you can use the station lines on the body plan for the Charles Morgan.  As you probably know there are 8 drawings of the Charles Morgan, including body plans, inboard profiles, deck plans &c. available from Mystic.   https://store.mysticseaport.org/ships-plans/morgan.html

 

Allan

Edited April 15, 2022 by allanyed

[Roger Pellett]

Master model maker Harold Hahn developed a system for mass producing frames for POF models from two layers of solid wood.  Standardized shapes were fabricated with mitered segments that followed the frame shape to avoid problems with cross grains.  The joints in the two layers were staggered.  Individual frames were cut from these blanks.

 

I have been thinking about using this system for producing POB bulkheads.  Same as for POF frames except skip the step to saw out the inside of each frame shape.

 

What would be the advantage of such a system?

 

It would allow use of inexpensive and readily available lumberyard pine that could be specifically selected for quality.

 

It would avoid problems with plywood or MDF; warping, fastening into edge grain.

 

There would be no cross grain to break.

 

Top timbers could made from high quality modeling hardwoods selectively added to the laminated blank.

 

Roger

Edited April 15, 2022 by Roger Pellett

[Bob Cleek]

6 hours ago, Roger Pellett said:

Master model maker Harold Hahn developed a system for mass producing frames for POF models from two layers of solid wood.  Standardized shapes were fabricated with mitered segments that followed the frame shape to avoid problems with cross grains.  The joints in the two layers were staggered.  Individual frames were cut from these blanks.

 

I have been thinking about using this system for producing POB bulkheads.  Same as for POF frames except skip the step to saw out the inside of each frame shape.

 

What would be the advantage of such a system?

 

It would allow use of inexpensive and readily available lumberyard pine that could be specifically selected for quality.

 

It would avoid problems with plywood or MDF; warping, fastening into edge grain.

 

There would be no cross grain to break.

 

Top timbers could made from high quality modeling hardwoods selectively added to the laminated blank.

 

Roger

What's not to like about that? I had good success in one instance years ago by laminating three layers of birch tongue depressors (readily obtainable in bulk from crafts stores and dirt cheap) with PVA clamped with binder clips. I used Underhill's method, later further popularized by Hahn, for angling pieces to form the rough frame shape, cutting the joints on a paper cutter, and then jig-sawing the laminated form to shape. It works fine. By overlapping the joints and tight clamping, very solid frames which will resist breakage otherwise due to short cross-grain orientation can be made. The only issue I had with it was that when finish shaping the frames on the drum sander, the PVA adhesive tended to melt with the heat of the sanding and gum up the abrasive. That was pretty easy to keep ahead of by slowing the speed of the drum and regularly cleaning with a crepe abrasive cleaning stick, but in the future, I'd look for an adhesive that was harder and less prone to gum up when sanding.

Edited April 15, 2022 by Bob Cleek

[Jaager]

As long as Roger and Bob have introduced POF intended to be totally planked, here is a way to do that:

https://modelshipworld.com/topic/22608-la-renommee-1744-by-jaager-160-frigate-pof-using-the-fully-planked-solid-hull-option-of-the-station-sandwich-method-this-option-is-offered-as-an-alternative-to-pob-using-filling-wood-between-each-mold/

Now, I would use knot and sap free construction Pine from a builder's supply instead of Hard Maple.  I would also forego any attention to port location during the frame-up.  The frames make it easy to site them later.  The inside can be rough and wider. I was being compulsive in the moulded dimension be determined by the scantlings.  The sided dimension can be whatever is convenient. Using 1/4" stock works well.  There will be an odd thickness layer in every station section to get distance correct.

 

If the hull is to be planked, only one layer is needed. If the hull is to be copper covered, and the frame dimensions are properly adjusted, no planking is needed where there is to be copper.  With a stencil and the proper actual copper containing paint, the bottom can be paint only,  The ModelMaster (?) line has old penny copper and with it being the actual metal, any  green oxidation can be place where it is wanted.

 

Until Roger and Bob brought the above subject up, I did not intend to present the above.  I wrote, but decided not to post the following:

An interesting tree     your namesake is.

Although it is not really a species for use with a scale model ship if the unpainted wood is to be on display,  you could use Burr Oak or any other Oak for molds, since it will be hidden.  It is not the best of choices, but it is an option.

 

A mold is actually what is named a bulkhead really is.  Western wooden ships did not have bulkheads.  Chinese seagoing Junks did have bulkheads.

 

A single piece of wood can be used for a mold.  The thicker it is, the better it will do its job.

A factor ruling against the use of solid wood for molds - at least for the larger scales is the width of the plank it must be resawn from.

Any Oak is fairly dense and offers resistance to being cut and shaped.  Clear Pine will do just as well and is less expensive.

 

There is a  scratch log for Charles W. Morgan  doing exactly what you want to do, and is POB,  right at the top of the 1801-1850 forum.