DVC's Shell Molding & Casting - New Photos

[demon-vice-commander]

I am currently working on a new Proton Pack buck that I plan to mold in the next few weeks. I originally started this project over two years ago, but being a complete amateur at molding and casting, my results were less than perfect. That’s not to say that the end product was a disaster by any means - I ended up with a very serviceable shell that (after extensive clean-up) became a pretty decent pack.

For anyone interested, here is my original build thread: http://www.gbfans.com/community/viewtopic.php?f=2&t=28672

I’ve learned quite a lot in the few years since, both about the original shells, mold-making, and general construction techniques.

My goal is to build what you could call an “idealized” accurate shell - that is it includes all of the correct parts molded on the original Hero shells, beveled corners, angled walls, etc. I am not including details like rough wood grain on the fins, penny head nails, etc.

Everything but the EDA and Attenuator (which were destroyed during the de-molding process) is from the original buck. However, I’ve added the correct bevels, edges, and other features. The past few months have really been nothing but sanding, filling, and mounting it to the board. I still need to add pilot holes for the Clippard, Vacuum Tube, and Shock Mount.

As always, I welcome any constructive criticism, particularly from any of the experienced shell casters.



The upper rings are new, but the lower rings are just the top rings from the original buck.


I’ve been adding the curved corners between the Corner Plate, Gearbox, and Gun Mount.


This is my attempt at the step-down from the Gearbox Tube to the Gun Mount valley. There really aren’t any clear reference shots that I’ve been able to find.


The EDA disks are just cut down film canister lids.


Curve between EDA and Power Cell


Curved Edge


Center Plating Bevel (left)


Center Plating Bevel (right)

Misc. Parts


New Gun Box - I need to learn how to mold this hollow…


Front Handle Base, Front Handle, GBFans tube


Rotating Barrel Mechanism


Here are some of the new labels that I designed - I’ll probably end up getting these printed on vinyl

[julz]

Looking good man

Nice Labels

[demon-vice-commander]

This was my first attempt at painting the buck. The base was a Rustoleum Satin Black with Rustoleum Hammered Black for the textured areas.



The hammered paint didn’t quite give me the textured look I was going for; it was actually smoother than I expected. Since I’m going to try the wall spray technique, I might end up using the hammered paint for the smooth areas - I really like the subtle metallic texture that it has.




In the end, the buck was still rough in a few areas, so I did some more filling and sanding earlier this evening. Tomorrow I’ll give the whole thing a Satin finish, followed by the wall spray texture, and finally a combination of Satin Black and sealant. Afterwards I’ll add the necessary pilot holes.

However, I am tempted to use the hammered finish for the “smooth” sections of the buck. Any thoughts?

[giric_thren]

Awesome job, I am currently building a buck now. Keep up the good work

[demon-vice-commander]

I added the Homax wall texturing today. It took two attempts; the first coating was too lumpy, so I wiped it clean, heated the bottle more, and used faster and lighter passes with the spray.








[demon-vice-commander]

The buck is pretty much ready to start prepping for molding. After adding some pilot holes, I decided to take a few final photos to better show the texturing. While there are still a few surface imperfections, I’m pleased with how it turned out.







[Wiz-GB008]

Nice job on the texturing, it looks really consistent.

[demon-vice-commander]

I know it’s been a while, but the weather has finally been warming up here in St. Louis, so I’ve been able to proceed with my new shell molding project.

The outer fiberglass jacket (including the other half) is about 90% done. I just need to patch up a few areas and reinforce the center that will eventually get bolted together.

[Hoot]

Thats looking good. Will you take us through the actual casting of a shell also?

[demon-vice-commander]

@Hoot

Will you take us through the actual casting of a shell also?

That’s the plan!

[Hoot]

Ooooooooh

[Hammer]

Anxiously awaiting progress!

[demon-vice-commander]

This thread has been in such desperate need of an update, you might say it’s starting to “mold”.

The past year has been pretty hectic, particularly with my wife and I finally buying a house, so this project has certainly taken longer than I had planned. That being said, I’m very pleased with the results and hope to give you a detailed look into my process for molding and shell casting…

First, let’s take a look at the buck, which was made by myself and forum member christphen. I took these photos shortly before covering the buck in clay prior to building the fiberglass support jacket (and yes, I rebuilt the fiberglass jacket to make it support the mold better before pouring the silicone).

I’d also like to give a shout-out to Vince, who gave me some invaluable advice throughout this proect. Thanks, chief!

I fixed a few details that were bugging me; first, I widened the space between the ribs on the Gun Mount, and added texturing to the side of the Power Cell (which I know isn’t technically accurate, but it just didn’t look right or consistent without it).

After bolting the master to the board, I sealed the edge with clay and proceeded to cover the entire thing in plastic wrap and about 3/4" of non-dry clay. When prepping your clay, you should roll it out into sheets about 3/4" thick and cut it into slabs. Also, don’t forget to add the 1" thick perimeter after the initial surface is laid; this is critical for your mold to grip the sides of the support jacket.

Before proceeding, it might be a good idea to talk about these razor throwing cards I made…

What you see here is nothing more than cheap playing cards covered in aluminum tape (which is extremely useful stuff, by the way). These will be used to form the barrier that separates each half of the fiberglass support jacket. I opted for three pour spots made from 3" PVC couplers, which will also serve as additional keys once the mold is done. They should be positioned at the highest points of the buck.

A quick note on the pour spouts - while you can use pretty much anything for these, avoid cups or tubes that have a taper to them - this makes it more difficult to get the mold flush into the jacket when you need to reassemble the whole thing after casting a shell.

I can’t stress the importance of keys - pretty much every vertical wall should have them. I made them about 1/2" thick and 1.75" wide. There’s no significance to the red clay; the store was out of white, and I thought the white and red combination gave it slight Ecto-1 look…

After I had enough keys and had smoothed the clay out as best as I could with a damp sponge, it was time to lay the fiberglass for the support jacket. Never a fun job, but I’ve done enough fiberglassing that it doesn’t really bother me anymore. However, here are a few tips for first-time fiberglass builders:

1. Fiberglass is dangerous; don’t inhale it. Use a respirator in an outdoor or ventilated environment.

2. You’ll need a ton of disposable chip brushes, rubber gloves, and mixing containers. All of these can be obtained at the dollar store (assuming you’re not ordering in bulk and doing this full-time).

3. Lay down some sort of covering on the ground/floor. A big cut-up cardboard box works great.

4. In warmer weather, the fiberglass resin will cure faster; as a rule of thumb, give yourself about ten minutes per 8 oz. batch. Of course, your working methods and amounts will vary.

5. When fiberglassing over the clay, lay about 1.75" of gaffer’s tape around the perimeter; this will help prevent the fiberglass from bonding to your board.

6. As you build up your layers (using more of a stabbing motion that actual brushing on the resin or mesh), wait for it to dry and inspect for holes, thin spots, etc. I used a sharpie to highlight these points to ensure that I didn’t have any weak spots in the support jacket.

A self-portrait before starting on the next layer…

I seem to have forgotten to take any more photos of the support jacket in progress, so we’ll jump ahead to its completion.

Now just bolt the two halves together, add several 1/8" OD air holes, seal the center seam with clay or hot glue, coat the interior of the jacket in petroleum jelly, bolt the entire jacket down to the board, seal the perimeter with clay, and you’re ready to go!

As for the bolts, don’t cheap out; use 1/4-20 thumb bolts with butterfly nuts - this will make assembling and disassembling the shell much faster.

Since the silicone pouring is a very precise and nerve-wracking experience, I didn’t get any good photos, so we’ll jump ahead a bit. After removing the support jacket, which came off with surprisingly little fighting, it was time to peel back the mold…

Now for the moment of truth…

Success!

I’ll go into the actual casting portion of the project in my next post…

[Wiz-GB008]

Nicely done!

That’s going to make some great shells.

[PredatorMV]

If you put plastic wrap in between your master and the rubber how do you not end up with some sort of wrinkles or loss of detail? Forgive me if that sounds dumb I don’t do casting and I am just curious.

[system]

I’ve never done this myself, but the way I understand it, the plastic wrap is only used in the creation of the support jacket, and is only to avoid having to clean clay off of the buck. You cover the buck in plastic wrap, then clay, and then create the support jacket over the clay (with pour spots for the silicone later). Once the jacket cures, you remove it, then remove the clay & plastic wrap, replace the jacket over the buck, and then pour the silicone so that it fills in the space between the buck & jacket that was previously filled with clay. Pretty sure that’s how it all works.

[PredatorMV]

OK that would make sense to me.

[Lewis_Tully]

This looks incredible! Can’t wait to start seeing pulls and packs off of this!

[Alan_Hawkins]

Congrats on a job well done!

[demon-vice-commander]

@Master Taran

I’ve never done this myself, but the way I understand it, the plastic wrap is only used in the creation of the support jacket, and is only to avoid having to clean clay off of the buck. You cover the buck in plastic wrap, then clay, and then create the support jacket over the clay (with pour spots for the silicone later). Once the jacket cures, you remove it, then remove the clay & plastic wrap, replace the jacket over the buck, and then pour the silicone so that it fills in the space between the buck & jacket that was previously filled with clay. Pretty sure that’s how it all works.

That’s exactly how it’s done.

Thanks for the comments, everyone. I’m going to post some photos of the two shells that I pulled in the next day or so, as well as a look at the actual process of casting a shell from a mold.