The Ship Model Forum

In "Advanced Ship Modeling," Brian King makes reference to a method for making ventilator cowls by electrolysis. He attributes it to a 1939 book by A.P. Isard, "The Model Shipbuilder's Manual of Fittings and Guns". Brian King did not know anyone who had actually tried the technique, and he suggests his own method for forming cowls out of copper. I decided to do the archaeology. On Abebooks, I found a copy of the Isard book, and it came in today.

Basically the idea is to make the master for a ventilator out of some friendly material such as hardwood. Then make a female mold in dental plaster. Then pour melted lead into the mold. Then perfect the lead piece.

The next step is to suspend the lead plug upside down in an electrolytic bath, and plate it thickly with copper. After the plating has been completed, the copper is "opened" with a sharp instrument at the point where the electrode was attached. From this hole the lead is melted out.

The copper ventilator cowl can then by finished by polishing, soldering a wire ring around the cowl, or adding cross-bar details and a deck-washer.

It occurred to me that in 2008, with the benefits of Rhino, rapid prototyping, and the modern pool of copper plating technology associated with PCs, etc., it might be worthwhile trying out this old method once again.

It might be possible to copper plate quite a few lead ventilators simultaneously. It might even be possible to get the whole thing accomplished by email, if you knew where to send the dxf!

In any event, has anyone ever tried this technique, or seen the results?

Regards, Michael

Gary Kingzett used a similar method a couple of years ago to make cowls for his model (the New Jersey, I think). He used a Cerro Alloy (low melt metal) to make the cowl, then electroplated metal onto it with a home electroplating kit, the one that you brush the solution onto the part. I think he used nickel and bought his supplies from McMaster Carr. After it is the right thickness, you just heat it up and the metal melts out, ready to be used again. They looked fantastic, but were very delicate.

mcg wrote: It might be possible to copper plate quite a few lead ventilators simultaneously. It might even be possible to get the whole thing accomplished by email, if you knew where to send the dxf!

In any event, has anyone ever tried this technique, or seen the results?
Regards, Michael

seen results for 1/30 scale = very nice, cost more than it was worth tho'
damaged too many just fitting the parts.
Well if you carved 1 up to start with & made a mold, silicon or even carved out of a piece of hardwood, for casting lead into, you could send it to a local plating firm.
They would return the parts & you melt out the lead, et voila!
Now the miniature bearings to make them turn thats another problem.

A google search for Gary Kingzett's New Jersey surfaced some commentary on ventilator making in his club newsletter, the Broadaxe, on page 4.

http://www.njshipmodelsociety.org/Main/ ... 202007.pdf

At an exhibition in Connecticut I saw this model -- it is really excellent work.

The difference in the technique from that suggested in the 1939 book seems to follow from the choice of Cerro instead of lead. Because of the low temperature melting, he was able use silicone rubber molds instead of plaster; when the time came to melt "lead", out from under the electroplate, he used hot water!

Here is another issue of the Broadaxe with photos of the cowled ventilators.

http://www.njshipmodelsociety.org/Main/ ... y2005A.pdf

and a nice computer rendering of the old New Jersey.

http://www.southjerseynews.com/brainsto ... s/bb16.pdf

Those ventilators were a prominent part of the superstructure.

...

Thank you for this link. SMS Iltis is a masterpiece.

Regards, Michael

I was wandering today and happened across this thread. Happy New Year everybody.

The copper plating method of construction is called electro forming. Standard plating deposits something like .0005" of copper onto a substrate. Electro forming deposits much more metal, I used .020", onto an armature, which is then removed, leaving the copper self supporting. I wish I had developed the method, but I got it from a handout from Clyde Emerson at the Western Ship Modelers Association conference on the Queen Mary in Long Beach, CA in 2002. It is also nicely outlined in an article by Phil Mattson in the Nautical Research Journal, Vol 46, No. 2, 2002. I had seen the Brian King method, and others similar, but I didn't like the lack of control they had. All their ventilators looked the same shape and proportion to me; Different real ships had different shapes. The New Jersey had quite unique shapes, very deep, with no raised rim, and there were 3 different sizes. I knew I would not be able to carve ventilators to a satisfactory contour and thickness. I don't like the shape which results from commercially cast ventilators, and I find it very important to be able to look down their throats, so to speak, so they look like real working vents. Most of my vents were about 1 1/8" dia across the mouth, others were about 3/4" and still others about 1/2".

I made 3 models of the outside shape of the ventilators, then made 2 piece molds of silicon rubber of each of them. I used Cerro Bend as the metal for my armatures. Cerro Bend melts at 158� F and is designed for ease of casting, i melted some in a tin can in boiling water, I was able to pour and demold about 16 of them in an hour on the kitchen stove. Yes, my wife is very tolerant of my foibles. I cleaned up the pouring gates and any flash, then drilled and tapped the end of each vent shaft and ran in a small screw to which I had soldered some #14 wire, then it was off to the plater. The owner of a local plating shop got interested in the project and did the plating for $150.
I know he didn't make any money on it, but he had fun, and so did I.

Using the wire, he attached all my armatures to a cathode bar and hung them into a plating solution. The other pole was a copper anode, which was sacrificial to replace the copper which was coming out of solution. It didn't require much current, about 2 amps for 4 hours, if I remember correctly. Unfortunately, that was still much too fast, the copper plated on very rough and somewhat porous. If i had been able to convince him to lower the current to a third, the plating would have been much slower, about 16 hours, but the finish would have been much smoother.

After we had deposited .020" of copper, we removed the vents, rinsed them and I unscrewed the wires. Using grit impregnated rubber buttons, files and sandpaper, I smoothed the outside. I used surfacing putty to fill a few porous areas, then was ready to remove the armatures. I sanded the mouth of each vent 'til all the copper was gone from there. I sanded slowly so the metal wouldn't melt out until I was ready. After I had all the vents trimmed to their final dimension, I dropped them into a clean can of boiling water and Voila, all the metal melted out of the inside. I cleaned them up a little using the grit buttons, trimmed the vent shafts to finished length, mounted them on their bases, primed and painted.

This made a great deal of sense to me, 10 finished vents in my scale of 1:144. I don't know about smaller scales. If you have experience making rubber molds and casting resin, this method would probably be worthwhile if you needed 3 or 4 or more vents of any one size. The Cerro Bend makes it very practical with its low melting temperature, lead melts at over 600�F, which is too high for the rubber molds. I suspect that a home plating set up would work for smaller pieces, you would want the metal somewhat thinner, and there would be less plating area. A friend of mine gave me a power supply, but i haven't tried it yet, my current project doesn't have any cowl vents.

There aren't a whole bunch of photos of my New Jersey around, I usually don't take her case off, but I did have the cover off at the IPMS Nationals in Atlanta for about 45 minutes (my heart in my throat the whole time) and the two Steves, Wiper and Backer took pictures. You can find pictures in the Battleship Gallery on SN, and it was featured in the 4th issue of Warship Modeler. That might give you an idea what I was trying to accomplish.

Gary

Hello Gary,
Many thanks for this thoughtful and thoroughgoing post. Glad you found us! We were talking about your New Jersey, as you may have noticed, but it is wonderful to hear straight from the source. I looked at the photos, they certainly show the value of the technique. Brian's King's concept of patiently stamping hemispheres with a tool and die is fine, if the subject cowl is hemispherical. Your technique offers complete freedom in the shape of the cowl. The information about the thickness of the plate, and the importance of slow plating, is especially helpful. The .020 is much thicker than I would have thought possible.
Regards, Michael

Gary, that's gorgeous. Here's a link to the page in question on the SN site.

Andy