Sunday, January 24, 2010

Rhino Gas Mask: The Finished Photos

I'm happy to report that the first Rhino gas mask is complete. It took me just under one month to construct from start to finish. Here then are the photos.

Since 73% of respondents to my poll on horn direction favored up, I have gone with that.

This first mask turned out smaller than I had expected. Definitely a size small. I have listed it on Ebay with a $1 starting bid. There are more photos there. Rhino on Ebay

Saturday, January 23, 2010

Rhino Gas Mask: Finished Canister

The Rhino canister model with the finished cold cast aluminum one.

The model weighs 392 gm, while the hollow cold cast version weighs a mere 91 gm (3.2 oz)! The wearer won't even notice it's there.

Thursday, January 21, 2010

Vacuum Formed Skin Tight Leather Mask

Here is a way to make a different kind of leather mask than I usually do, using the power of a vacuum to shape the leather.

Pictured above is my set up, consisting of a vacuum pump and hose connected to a piece of iron pipe. The bottom of the pipe is closed off, so that when the pump is engaged a strong vacuum pulls from the top of the vertical pipe. Into the open pipe I place the form that I am going to use, in this case a life casting of a woman's face poured in plaster, with a smaller diameter iron pipe protruding from the bottom.

The smaller pipe inside the larger pipe still allows the vacuum to suck air. For my leather I have chosen a very thin lambskin, as it will absorb water when immersed, and then become plastic. At the same time it won't allow any air to pass through it, so that when I firmly wrap the lambskin around the larger pipe, the vacuum pulls the damp leather down around the face.

To ensure a good pulldown all around, I drilled small holes in the recesses of the face: The inside corners of the eyes, the nostrils, and the outer corners of the mouth. I also worked it with some dull metal tools to help the leather conform.

Once it drys it can be removed from the form, and it will retain its shape. Here is the mask after it is cut off of the plaster face.

This view shows it from the inside. You can see that at the chin and forehead I was unable to stretch it sufficiently to remove all of the wrinkles.

Wednesday, January 20, 2010

Making a Fiberglass Mother Mold

When making a silicone rubber mold (into which is cast resin) there is typically a supportive outer shell, called a mother mold. Often the mother mold serves another purpose as well, that of containing the liquid rubber while it cures into a solid.

A very simple and easy-to-use container for making many types of molds is a paper cup. I have a supply of picnic and popcorn cups in various sizes for just this purpose. For most castings, the paper cup will work also as the mother mold, keeping the mold parts tightly together while the liquid resin cures. For the Rhino canister mold however, I need a rigid mother mold, and here's why.

Due to the fact that I need the cast part to be as lightweight as possible (so that the gas mask will be comfortable to wear), I am going to make it hollow, and the most efficient way to do this is in a rotocasting machine (which holds the mold and rotates it in two different axis at the same time).

I need to clamp the mother mold (and silicone daughter mold) into the rotocaster, and to withstand that pressure I need a rigid mother mold, as the paper cup will just squash. These pictures document the procedure for making this.

The top picture shows the blue silicone rubber mold after it has been removed from the popcorn cup. Below that I am pulling on a 3" diameter nylon stockinette.

I cut the stockinette long enough so that I could double it over. Here I have loosely tied a string around the top.

Now I have pulled the top half of the stockinette back over the bottom half, so that I have a two layers.

Here I've mixed up polyester resin with an activator (and violet dye), and brushed it all over the stockinette until it's saturated.

And here is the final result after it has cured, with the rigid mother mold on the right.

Tuesday, January 19, 2010

Steampunk Leather Top Hat Tutorial

I have received several requests for a tutorial on making my steampunk leather top hat, shown above, and so, here it is. The first drawing shows the three pattern pieces (not to scale). The wave on the bottom of the crown is what gives the brim its distinctive curve.

The pattern below is the one that I used to make my top hat. For a size large, the width of the crown (from side to side) should measure 23.8". You can print it out and enlarge it to get it to lifesize. The crown has four optional darts (butt seamed), which give it the modified hourglass shape.

The crown joins at the back with a butt seam. If you add a seam allowance you can convert it to an overlap seam and sew it on a machine. The wavy bottom gives the brim the nice shape of down in the front and back, and up at the sides. The dotted line on the brim is where I folded the edge in over a wire.

You should use a lightweight but firm vegetable tanned leather. This will allow it to become malleable when wet and you can form its shape after all the pieces are joined.

See the diagram at the lower right for construction details. First, sew the crown to itself. Then stitch on the top and turn inside out. Then pull the brim down over the crown and glue, then stitch. Lastly sew the brim outer edge over a wire. You can lace up the darts either before or after attaching the crown.

This is the partially made hat. Notice how badly shaped the top is at this point. Not to worry, as you can reshape it at the end, then let it dry before dying or painting it. Mine was airbrushed with thinned acrylic paint.

Monday, January 18, 2010

Rhino Gas Mask: Strap Design

The Rhino is my fourth gas mask. The first one—simply called Gas Mask—was the first steampunk item I ever made. Since making other styles I now refer to this design as No. 43.

Pictured above is a No. 43 showing the straps, with the buckles attached to the mask surround and the straps made up of four pieces of leather, riveted (or sewn) together. My second gas mask was Pachydermos, which combined elements of No. 43 and the canisters of my first respirator, the Bad Air Transmutator. It kept the same straps as used in No. 43.

My third gas mask was part of the Sentinel ensemble, shown above. The straps were once again similar to the first two, with slight design modifications.

For the Rhino gas mask I've decided to make two major changes in regards to the straps. First of all I have streamlined the pattern into just two pieces, seen below.

And secondly, I've reversed the buckles and straps from the previous versions. On the Rhino, the free strap ends will be pointing away from the face.

Sunday, January 17, 2010

Rhino Gas Mask: The Canister

I was feeling really stuck on how to build the canister. The primary problem in my mind was getting it to fit with the look of the eyepieces and horn. Those two are both strong designs with little subtlety and no detail.

I decided that while I could keep the basic bulky shape of the canister, that I would need to build it from scratch (and not simply modify the original one), in a manner similar to the nose horn, and in the same material. Here is the acrylic and resin model, and the engraved bottom part (made of acrylic and Bondo™), which will be attached before molding and casting.

Wednesday, January 13, 2010

Pictures of My Early Leatherwork

In order to give you a little background on me and my leatherworking, here are pictures of some of my early work from the 1970's and 80's.

Shako based on 19th century U.S. army hat

Detail of recorder case showing tooled leather medallion and handmade oak handle

Commedia del Arte mask
(only the second mask I ever made)

Leather drinking flask made for my SCA costume
which holds a cold beer

Medieval pointed shoes
also for an SCA costume

Leather camel over a wooden base
about 18" high

Saturday, January 9, 2010

R.H.I.N.O. Gas Mask: The Canister

Yes, Rhino is now an acronym: Respiratory Hindrance of the Inhalation of Noxious Odours. Now there is a story of how the Rhino Mask got its name! Anyway, I've been thinking about what shape to make the air purifying canister, and after much deliberation have decided to stick closely to the original.

Here you can see a photo of the mask (minus its straps). The large squat tubular form of the attached canister is quite common, and strictly functional. Given that the horn nose has a strong fantasy element to it, I think that the canister balances it nicely by keeping the simpler shape.

Of course I will gussy it up some, giving it a real Victorian look with leather, and decorative reliefs, etc. Beautiful yet functional. That is the plan for now, always subject to change. Above is my sketch that I'll work from.

Wednesday, January 6, 2010

Rhino Gas Mask: Whither Points the Nose?

Rhino is from the Greek word for nose, and there is no doubt that this mask prominently features that part of the face. The question now arises, "Which direction should the nose point?" Initially I was planning on pointing it up to resemble the horn of the rhinoceros. But once I had cast the horn and was putting it into the leather mask, I realized it could just as well point down. So now I am asking you, the readers, to give me your opinions on the matter. To that end I have put up a poll (in the upper right corner of the page) and invite you and your friends to vote, and let me know what you think.

As you can see from the photos I have dyed the mask black, and inserted both the nose horn and the eyes. The canister is still to be designed and built, and it will no doubt change the overall look of the mask, but meanwhile let me know what you think about the orientation of the nose.

Tuesday, January 5, 2010

Rhino Gas Mask: Eyepieces

I wanted to do something new with the eyepieces for this mask, different from what I'd done before. In the past I've used camera lenses, and several fabricated eyepieces, but they have all been circular. The rubber German gas mask that I pulled the pattern from also has round eyes, but after taping and making the 2D pattern, then cutting it out of leather and reassembling it as a 3D mask, the eye openings were no longer round. I could have easily inserted round eyes into the leather mask and it would have conformed seamlessly, but I felt that I had already done enough round eyes, and in this mask they even made it look a little goofy.

Thus I decided to go with the organic shape that the mask naturally took (seen in the shape of the clear lens above). Then I thought "Why leave the perimeter smooth?" and opted instead for a mishapen octagon. And one more innovation: Adding brass crossbars to protect the lens from breakage.

Above are the individual pieces: The base part cast in black resin, the clear acrylic lens, the cold cast aluminum cap, and the five brass rods.

And here is the assembled eyepiece for the left eye. The right eyepiece is a mirrored image. I fabricated both the base and the cap out of sheet acrylic. To the cap I added eyelets and machine screws, then molded it and poured it in cold cast aluminum. Now that is a different looking eyepiece!

Monday, January 4, 2010

Rhino Gas Mask: Cold Cast Horn

I've now cast the rhino horn in cold cast aluminum. Below you can compare the model (on the right) with the finished piece (on the left).

Designing a piece of art such as this requires being able to look at the model—here made of an unsightly conglomeration of resin, acrylic sheet, copper wire, metal eyelets, and brads—and see the finished horn, in all its beauty. (You do think it's beautiful, don't you?) That is the wonder of resin casting, and especially cold cast metal casting.

Cold cast is nothing more than mixing a very finely ground metal powder (in this case aluminum) into resin. Once it has hardened, I sand the surface of the casting to reveal the aluminum beginning with 180 grit, and continue with finer grits all the way up to 0000 steel wool.

The final step is polishing the piece with a Dynabrade rotary buffer, using a foam pad and compounding liquid. That final polishing is the key to getting it to shine.

Saturday, January 2, 2010

Rhino Gas Mask: Finishing the Horn Model

Continuing work on the horn model, I've added red metal eyelets and a faux pearl at the top. The model is now complete.

Once the horn is cast hollow in cold cast metal I'll drill through the eyelets to create ventilation holes in order to make breathing easier for the wearer.

In preparation for making the silicome rubber mold I've hot glued the model upright on a scrap of Formica®. The popcorn cup will be hot glued down around the horn, and will contain the liquid rubber while it slowly cures. The white plasticene around the base of the model will become a separate rubber plug which will keep in the liquid resin during the rotocasting process.

Friday, January 1, 2010

Rhino Gas Mask: The Horn

This gas mask was begging for a nasal projection, and so I am obliging it by constructing an exhaust vent reminiscent of a rhinoceros horn.

Here is my concept drawing. The challenge was to make it look mechanical and man-made, while still reminding the viewer of something organic.

I started with a cast resin horn that I've been making for a satyr mask to sell on my Etsy store. I added several rings that I cut out of acrylic sheet (secured with brads), and four pieces of copper ground wire.

The horn will be made of cold cast metal. Like many of my resin mask pieces, it needs to be lightweight, and so I'll cast it hollow. That process is called rotocasting, and it involves taking a regular rubber mold (which can be closed up) and pouring a small amount of resin into it. While the urethane resin is still liquid, the mold is rotated in all directions so that the inside of it gets coated with the resin.

I will do this twice to build up the resin thick enough to be sturdy. In the photo above I've coated the model with white resin to smooth out the inner corners, nooks and crannies. This will make a better mold for rotocasting and will result in a stronger part.