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The Gunner Turret Ring
The rear position for the radio/radar operator of the SBD served double-duty as the rear gunner as well. This multi-tasking meant that the crewman had to be able to sit in a forward facing orientation to operate the radio and radar equipment, but quickly spin around to man the rear guns of the SBD to defend against those nasty bandits on his six!
To make this an easy and efficient task, the SBD rear seat was housed in a circular ring that the gunner's seat was suspended from. The seat was attached to the main ring on a series of rollers that allowed him to quickly swivel his seat 180 degrees to switch between the forward and aft facing positions.
The twin 30 caliber flexible mount machine guns that he manned were mounted on a post that was fixed at the rear most point on the ring. When he swiveled, the gun stayed there, however the gun was able to pivot all the way from port wing to starboard wing, giving him a full 180 degree attack cone to the rear. It also pivoted on the X-axis allowing him to arc the gun from a level position to a position about 20 degrees shy of straight up. This page will show you how I fabricated this turret ring and seat, but will leave the gun fabrication for the next page.
Building up the Main Ring
I built the main ring by first gluing a strip of 1/32" aircraft ply end to end in a 4-1/4" circle. I then glassed it with 3/4 oz cloth and epoxy resin to give it torsional stability.
Next, I laminated both sides of the ring with 20 mil styrene sheeting, which gave it a LOT more strength as well as a good smooth surface.
I had already determined that I wanted the ring to be removable and glued hardwood mounting blocks into the fuse. So, I now cut notches for the ring to fit onto the mounting blocks in the fuse and added another 1/32" ply doubler around the notches.
I then glued dowel rods to the inside of the ring to start the main down-tubes that would carry the seat.
Next was the heavy steel back ring that the seat hung from and swiveled with. This was made from balsa sheeting and surfaced with styrene.
I then made the 4 standoff brackets that held the 4 down-tubes, making them out of aircraft ply and styrene. Two of these brackets mounted on each of the two seat down-tubes and also attached to the tubes for the chest protector to follow.
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The Seat & Protective Guards
There were two "axe-shaped" armored chest protectors on the gun ring that could be rotated forward and out of the way when not in combat, or swung back against the gunner's chest during combat. I made these two guards out of balsa stock and surfaced them with 10 mil styrene. I buried a styrene tube in one end to build the smooth, curved end, and slid a smaller diameter styrene tube into it to form the two down-tubes.
Next was the seat. First I made the structural base that the seat would rest on and attach to the down-tubes. This was made from lite ply, plywood and balsa.
To make the seat itself, I cut two pieces out of 1/32" aircraft ply... one for the back & sides, and one for the bottom. I added balsa tri-stock around the side and back edges of the bottom piece, beginning the slope that would form the curved shape of the seat bottom. Once all was glued together, I sanded the corners on the outside bottom, to form the curve on the outside.
I finished the curve up by adding Squadron White Putty to the tri-stock and sanded smooth. The seat was then securely glued to the supporting base.
The last protective guard was the perforated shield that went around the back half of the ring on the outside. This was made from 20 mil styrene sheeting, holes drilled and additional styrene trim detailing was done.
Now I had to surface everything to prepare for final detail and paint. The main ring and down-tubes all needed to be a natural metal finish so they were covered with FliteMetal. The rest of the components were going to be green, but some of them would need to have the paint "worn" down to bear metal, like the seat bottom and back. So I surfaced these parts with FliteMetal as well.
With all the FliteMetal applied, I now needed to mount the perforated shield. I made standoff mounts out of solid styrene block and glued them to the outside of the ring. But first, I cut away the FliteMetal and drilled anchor holes where each block would mount. This gave me a much stronger glue joint. Lastly, I added the rollers, pulleys, and other minor details... all made from styrene.
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Final Details, Paint & Weathering
With everything constructed, I proceeded with painting. First, I masked off all the areas to remain natural metal finish. This was done by brushing on Bob Dively Liquid Mask. After the mask dried, I painted everything with acrylic Zinc Chromate Green. Most guys would remove the mask now, and be done with the component. I like to add the extra touches that make it look very real, so there are a few more steps.
The first was to do all my usual weathering and distressing. This begins with the airbrush, and is followed by finer detail weathering done with a fine 00 brush. Also, I use a small piece of fine sand paper and steel wool to wear through the paint to bare metal in areas of wear or abbrasive contact. After I finished weathering, then I removed the mask.
Next I picked up a few materials from the local fabric store to add a few more details. The seat had an additional webbed seat back that strung from one side of the ring to the other. I made this out of "iron-on knee patches" which I painted with thinned down Titebond glue. I sewed it up with elastic bead cord and did final painting, weathering and installation.
Lastly was the cord that ran through a series of pulleys under the seat. I believe this was a "bungie cord" of sorts that supported the rear of the seat and acted as a crude "shock absorber" for the gunner seat.
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Installation
The photo at left shows the finished gunner ring after all detailing and painting. As I mentioned earlier, this is a removable turret ring, so I will mount it into the fuse by running two hex head screws through each side of the ring and into hardwood blocks that are glued into the fuse walls. This will allow me to pull the ring out in the future should I need to repair it and/or any of the other interior components. I also still have to determine how I'm going to secure the crew figure into the ring, so this will be easy since I can pull it out to work on it.
 In case you're still keeping tabs on how much weight I'm adding, I thought I'd throw this last pic in for you. Although the finished ring looks very heavy, it came in at only 2.1 ounces. I had it at 2 ounces even, before painting and adding the last few details, but I think I can still live with the extra .1 ounce that the last steps added. We'll have to see how light I can get the guns and ammo belts now!
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All finished and ready for the Twin 30's...
Well here it is all installed and ready for the twin 30 caliber machine guns. I started them today, so check back soon and you might see them bad boys ready for action!
"Twin 30 Cal Guns"
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