Perry PC-3A1 — 2-man mini sub

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Re: Perry PC-3A1 — 2-man mini sub

This shows the collection of all the small parts I've made so far.

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Re: Perry PC-3A1 — 2-man mini sub

These are the masters I made for the windows for the port holes. These aren't clear, but after molds are made of them they will be cast in clear Alumilite.

You can see the lights reflecting off of them showing that they have a glass-like finish. This was accomplished by using a piece of plexiglass as the outside window part of the mold. Picked up the perfectly shiny texture without any further polishing.





I'll make the steel retaining rings out of photo-etched stainless.

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Re: Perry PC-3A1 — 2-man mini sub

These are little rubber bumpers that go along the sides of the keel, probably to protect the hull when it's put on a trailer. The one on top is the master that I carved out of a waste chunk of Alumilite. The other is the first casting of 8 needed. They are only about 1/4 x 1/8 x 1/8 inches in size.



You can see them along the side of the keel on the plan here.

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Re: Perry PC-3A1 — 2-man mini sub

Got a little time to work on this tonight. Thought I'd start working in the prop shrou--the little ring around the circumference of the prop in this photo.



I started earlier by hunting around for something that was either the same I.D. Or O.D. In circumference as the shroud. I found this piece of PVC that the O.D. Matches the o.D. Of the shroud, and a stainless steel baking ring that matches the I.D. I chose to use the one that the outer surface matches the I.D. because it is easier the wrap fiberglass around the outside of a tube rather than on the inside.



So I cut some fiberglass to fit around the metal ring and glassed up a couple of layers on it, making sure to use a release agent and have some hang over the edge do I can grip something to pull it off when cured.



Once I get this off ill be able to determine the thickness it is, and needs to be, and can then wrap more layers around it if need be.

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Re: Perry PC-3A1 — 2-man mini sub

Here is the prop ring pulled off the mold and cut to size, filled and primed.





Here is how the tapered panel that goes behind the crew cabin is going. Fiberglass is complete. Now time to fill in glass pores with body filler.

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Re: Perry PC-3A1 — 2-man mini sub

Here in the photo you can see the tie-down cable coming out of the side of the hull.



I made it by stripping the insulation off some copper wire. Then twisted it to look like metal cable. Coated it with solder so it wouldn't unwind while bending it. Bent it to shape and put small brass washers over it and inserted the wire into some brass tubing. I soldered the washers to the tubing, which also holds in the cable. The washers become flanges to the cable openings in the side of the hull. The tube parts will be able to insert into holes cut into the hull. Now I'll make a mold of this to reproduce two identical tie-down cables, one for each side.

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Re: Perry PC-3A1 — 2-man mini sub

Here how prop ring will fit onto beaver tail.

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Re: Perry PC-3A1 — 2-man mini sub

Next step is to make the little protrusions that stick out off the bottom sides towards the stern. You can see them here in the black area near the center of the photo.



I'm not sure what these are, but my guess is that they are emergency ballast that can be dropped to increase buoyancy. Regardless, they must be made.

You can see on my plan two views, from the side and from the bottom.





Since they seem to be symmetrical from the bottom I will try to make one half of one of them by screeding (I think that's what it's called) out of polyester auto body filler. By cutting half the shape in a sturdy piece of cardboard, I can drag it along a straight edge over a pile if body filler. Then cut out lengths of cured filler, put them together back to back and have the main shape.

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Re: Perry PC-3A1 — 2-man mini sub

After cutting out 4 pieces for the two protrusions, I used a process I call contour sanding to make them fit the shape of the hull so they have the same appearance as the photo, where they look like they are pushed into the sides of the hull.

This is done by adhering, or holding, a piece of sandpaper to the part of a master you want the new part to conform to. Then sand the new part until its shape matches that area it needs to fit to on the master.
You can see here where it's supposed to go, but the tip of my piece is flat, the side of the hull is angled and curved.




Sand. Sand. Sand until it fits.




I did the same with the back half.


I glued the two halves together, then to get an exact fit, I applied some mold release to the hull master where the parts will go. Then applied some fresh-mixed filler to the areas where it must fit against the hull and pushed it into place. This eliminates any gaps and is exact compared to just the sanding.

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Re: Perry PC-3A1 — 2-man mini sub

Once the filler cured I popped the parts off of the hull and cut them down to the right size. Here they are.

Perfect fits that even include the exact uneven shape of the weld lines on the hull that run underneath them. Next I will fill in the gaps between the halves that were glued together and add filler and glazing to the surfaces to get the extrusions smooth. Then I'll add the other little details to the surfaces. More to come.

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Re: Perry PC-3A1 — 2-man mini sub

I also did some bress work and made the lower arm that holds the rudder and prop ring in place. This will get attached to the bottom of the hull with two screws, and to the threaded strut probably with a nut.

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Re: Perry PC-3A1 — 2-man mini sub

Here are what I thought were ballast weights finished. Added surface details.





After looking at my photos longer and closer I am now thinking these are the ballast tank inlets. It looks like that are open on the bottom and are welded to the sides.

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Re: Perry PC-3A1 — 2-man mini sub

I feel like I'm starting to get bogged down on the remaining parts for the stern because I'm not sure of dimensions without the actual model to fit to. So I've decided the main hull part is complete, so I can make the mold for it and make a casting. I'll be able to start assembling the model then use it to complete the remaining parts.

I'm starting by determining where ill part the mold. Because there are lines to divide the top and bottom sections of the hull that have under cuts on both sides for each, I'm going to make at least a four piece mold. I may make it more by making the ends separate pieces too. The plan is to make two top pieces and two bottom pieces, split down the middle from front to back.

My mold dividing line doesn't follow a single plane, so my parting board will have to angle for the joint of the cover on the stern. First I traced the actual outline of the hull to a piece of cardboard.

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Re: Perry PC-3A1 — 2-man mini sub

After cutting out a hole from the tracing, I positioned it at the level break point.


It didn't fit close enough to fill in the gap with clay on the real parting board, so I spray mounted strips of poster board all the way around the edge to create an even gap all the way around. I'll use these pieces of cardboard as stencils to mark the opening to cut in the real parting board.



Next I made another piece for the angled section. I'll mount a separate piece to the straight parting board to create the angled seam in the hull sections.





You can see that I've started putting coats of wax on the plug by the way it's shining now.

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Re: Perry PC-3A1 — 2-man mini sub

Finished the template and traced the outline to the wood. I'm using the same kind of 1/4 inch panel that peg board is made of, without the peg holes.



I cut out the opening and fit the plug in.


Next I tried to add pieces for the front and rear angles, but I couldn't get the undersides sanded down enough to create a smooth transition to the angles.

So I figured since this wood is so thin, and there's no grain to deal with, I figured I can actually bend this wood. So I knocked the panel off of the box to get to the back side and cut two rabbits to allow the wood to bend without breaking.