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Sculpting more Rahm Kota armor

Koda Vonnor

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Speaking of practice, this sculpt went much faster and easier than the last ones. Here it is shaped, scraped, smoothed and walled. I kept the edges very thin this time based on lessons learned from the other two fiberglassing attempts. The edge trim will add the right thickness.


The divider cuts are still a bit off, but I can live with 0.125 diff. Won't be noticeable when worn.


Will take the molds later today or tomorrow then sculpt the left arm - I want to do all the fiberglass castings on the same day.






~ Vonnor

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Here is the left vambrace plates sculpt, with tapered mold walls added and right vambrace molds in the BG. Note the major wall taper at the ends of the channel divider cuts. This is so that the skewed edges of each mold half will clear the plaster armature when removed from the model. I broke a mold a couple tries ago and after adding these tapers had no problems the last go-around.






More to come.


~ Vonnor

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Vambrace plates:






They came out very nice contours and fit. I did get a small bit of damage on one of the edges, but the edge trim and fill will fix that. I also gel-coated the inside surfaces smooth to help facilitate free rotation/pronation over the shirt.


I'll polish the surfaces and add the edge trim at the Garrison Tyranus armor party next weekend. Right now they're still a little tacky so I need to let them dry.


Stay tuned.


~ Vonnor

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I was wondering why the surfaces of the plates were still sticky after 3 days. I used about 60/40 mix of Bondo/poly-resin to coat the outsides and insides. The insides really need to be smooth and dry so as not to bind up on the shirt during pronation/rotation.


According to google, the resin you can buy at Home Depot is what they call laminating resin, and contains an air inhibitor that keeps the surface tacky so that subsequent layers of laminate (glass cloth in my case) will adhere more easily. Bondo does not have that property, and normally you'd apply the final spread of full Bondo, like in auto body work. The Bondo keeps air from reaching the resin below, so the resin cures fully. My surfaces are still tacky because I used a resin/Bondo mix.


There was a lot of advice on how to remedy the situation, and the quickest solution was to use an epoxy finish coat. I got some Z-Poxy from a local RC model shop and will see how that works.


More later.


~ Vonnor

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I used the Z-Poxy (Zee-Proxy I call it :mrgreen:) on the insides of the plates, and they cured very hard and shiny. A little 320grit should keep them from sticking to the shirt fabric. I chose not to use the stuff on the outsides, because after I sanded the surfaces with wet220 they lost all the stickiness. They did have a lot of surface ripples though, so I spread a thin rondo (25/75 resin/bondo) correction coat and after it set up I wrapped the somewhat sticky surfaces with plastic wrap. One of the google'ations suggested that. It' keeps the air from getting to the air-inhibited resin and lets it set up completely. We'll see if it works.


I also poured the production hand guards this morning. Here are the rough pulls using the mold bottoms as forms while they fully cure. The plastic-wrapped vambrace plates are in the BG. I'll hit them with the mouse sander at the Garrison Tyranus armor party this Sunday.





Stay tuned.


~ Vonnor

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After sanding down the Bondo correction coat, I added the axial edge stripping. The radial edging will not go on until after the wrist-clip sculpt. I jigged it up with some temporary spacers and center-line markers, then cut the strap slots semi-freehand with a Dremel dental bit. I did use a metal guide that I clamped to the work piece, and just ran the spinning shaft up against the guide as I cut the initial slots. It took a few hours just to widen and angle the slots to receive the straps. The slots still need to be about a millimeter thicker to get 3mm straps into them. Using the cutting guide and taking it slow on the slot widening really came out a lot cleaner than the first attempt. I'm going to sculpt the wrist clip on the left arm, as the symmetry came out much better than the right.


One interesting thing I stumbled upon as I practiced free-hand Dremelling on a previous failed vambrace plate: I might cut the straps out of the junk hard models. The contour curve is about perfect and the 4-layer laminate allows a bit of flex. Using the polyester resin to bond them will make a ultra-durable production piece. The only challenge will be insuring uniform strap thickness.


I also noticed after taking the hi-rez close-ups below, that my cut corners were not so sharp. I have since rectified the situation. You super-observant folks will notice how many layers of cloth were used in the laminate.


Next up, straps, elbow guard and forearm plate. The closure design is slicker than the TFU version, and just as hidden. You don't wanna miss that. 8)









~ Vonnor

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I finally got back to this after 3 months off. Today I marked and cut the strap slots in the right radius and ulna plates. It took almost 3 hours to Dremel them and hand-taper the openings. Tomorrow I will cut two sets of straps from Sintra and thermo-form them to fit the slots. Time permitting I will take rubber molds of them.


After much study, I decided to make the production straps from 4-5 layer cloth fiberglass and bond the straps to the side plates with polyester resin. That will make them solid units on the palm side and I won't have to worry about tension or alignment issues while worn.


I also fit the right plates back onto the sculpting form to check fit and contours. It looks decent. Note the extent lines on the plaster arm, I'll have to trim some off the elbow and wrist ends of the plates which I anticipated. That's why I left the edge trim off the ends for now.






~ Vonnor

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lookin' good there Bill, I'm really looking forward to when get this "done" ^_^...

Thanks Katie, I am too. :P


Small update:


I cut and thermo-formed the straps for the left gauntlet. They are 3mm Sintra and I used the ductwork mandrel in the background to form the initial curvature. I then stuck one end of a strap at a time into its corresponding slot and manually heat-bent it flat against the curve of the main halves. I did this very slowly so as not to distort the overall curvature. My goal here was to make the strap masters with uniform overall curvature and the little hook bends as they go into the slots. I will take a plaster-backed rubber mold of these and cast them in 5 layer cloth fiberglass for strength with rondo coat on the facing surface. They will be bonded to the main sections with poly-resin and a pinch of Bondo thickener. Going by past experience they should have a slight flex, enough to get them on and off my arm.


More to come.






~ Vonnor

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I took those strap models and squared up the edges, smoothed the curves and finish-sanded all surfaces. I then super-glued them to a 110lb card-stock backing and sprayed a clear-coat over it all. I built up some layers of Rebound-40 silicone rubber taking care to taper away the undercuts at the ends. I could have used Rebound-25 but this was what I had on hand. It's pretty stiff if you never used it before. Since it's a junk mold for the most part (unless I mess up something) it should do fine. I undercut the side edges of the rubber wrappers a bit so they would hold better in the plaster backing. I hot-glued a box around it and poured in some plaster. Have to wait for warmer weather to lay in the fiberglass, but I'm liking how smooth the curves and surfaces came out.


More later.








~ Vonnor

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Today I cast the left gauntlet cross straps in fiberglass. No real issues, just had to use a lot more hardener in both the Bondo and the polyester resin since the temperature was about 65°F.


One thing new that I tried was some Bondo glaze putty for the "gel-cote" layer. It's a lot smoother than rondo and spreads very nicely. I painted the insides of the molds with some of that first, then 5 layers of fiberglass cloth and a thick rondo (resin/bondo 25/75) backing coat. Still some pinhole bubbles in the surface but I can fill those. They have a stiff flex to them which will be perfect for opening the gauntlet to get my hand through.


Here is the rough breakout of the castings:




More to come.


~ Vonnor

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The weather was warm enough for fiberglassing today, so I shaped the straps and bonded them to the radius and ulna plates using polyester resin. They came out very solid with just enough flex to get my hand in. I still have a bit of cleaning up to do and gaps to fill but all-in-all I'm happy with the results. I tested the fit with a 6mm soft neoprene band between the armor and my skin. The scaling of the original sculpt turned out perfect. The armor squeezes the rubber which holds it from slipping down to my hand. Once the wrist-clip and the forearm plate get on there It'll be one solid unit. It was really great to finally be able to wear this thing. :D


Next up is the gauntlet closure and wrist-clip sculpt.







~ Vonnor

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I made another armor part yesterday. Used paper to measure out a template and to get the "lean" angle right, then drew it up in Turbo-Cad. I cut the main piece out of 3mm Sintra and used a straight-edge and a sharpened eye-glasses screwdriver to cut the grooves. I cut out the raised edge trim from 1mm Sintra and used Azek PVC cement to glue the two together. I can't heat-bend it yet since it takes a couple days to completely dry.


Don't sound like much but still took about 4 hours, mostly tweaking the curves till they looked like the references. I'll bend it to shape and add the closure system probably next week.


I did see after fitting it, that I'll need to cut about 0.5" to 0.75" off the elbow end of the radius and ulna plates to get the scaling to look right.


Little bits at a time, it goes on. :P




~ Vonnor

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After reading back through this thread as posted on the Replica Props Forum (therpf.com) I came across a comment about the edge beading on the shoulder bells. I had used a soft cast urethane rubber beading for the raised edge of the hard model before I took the production mold. It was much easier and cleaner that sculpting a clay edge.


That got me thinking.


I have had a great deal of trouble in crafting the forearm coverplate for the vambraces. Sintra proved to be difficult to contour properly, so I am going to try casting a soft urethane coverplate and gluing it to a styrene sheet wrapped around the main sections. Then I can take a mold of that and cast it in fiberglass, and add the edging post-cast.


I also tracked down a 5/64" engraving bit for the dremel, and used the router attachment to make clean grooves in the scrap model.


I'm using Smooth-On Mold Star 30, to be backed with plaster when dry.







More to come soon.


~ Vonnor

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A 100 watt lightbulb took the 6hr cure of the Mold Star 30 down to 90 min. I'm going to wait a couple days for the plaster to fully dry before pouring the urethane rubber soft model, as any moisture will bubble it up something awful.


The casting will be slightly oversize to allow for the fiberglass cloth fringe at the edges, which I will trim off to the final curvature. That way the edges will be a little stronger than if they were mostly Bondo.



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As you can see I had to take another mold of the flat forearm plate model. The MoldStar30 did not perform well under heat. I know that it was due to the shelf age of the liquid materials but I wanted to give it a try.


The Reoflex 40 was very old as well, with most of the rubber solids having coagulated on the bottom of the resin, and the hardener was almost too thick to stir, but I also wanted to see if it was salvageable. As long as it doesn't inhibit the silicone mold cure I think it'll work OK. The sample in the 1st pix shows the correct cured color.


I used a thin sheet of styrrene to form the normalized contour around the gauntlet assembly, and superglued the soft plate model to that. The lines are close enough to straight as not to be noticeable in production.


I will take a brush-on mold of this tomorrow and cast the hard model in fiberglass. The final cutout shape and the edge stripping will be done on the fiberglass piece.










More coming soon.


~ Vonnor

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Made a mold of the forearm plate out of Rebound40 silicone rubber and backed it with plaster. Here it is ready to bake for a few hours (to get all the moisture out) then lay in the fiberglass.





~ Vonnor

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Love seeing how this build is progressing. Keep up the excellent work! I am very excited to see the whole costume come together at the end.




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Thanks Deez. :D


I made the fiberglass forearm guard this weekend. Since I wanted a very clean cloth lay-up, and scissors would have been a challenge with all the curves, I tried printing templates on card stock and taping them down to the cutting board with the glass piece in between. This worked like a charm and rendered six super clean sheets. Exacto cut through the glass like butter. For the template I used the same cutout as for the flexible model, but skewed it more vertical. Since the cloth will self-skew back to the proper contour as I lay it into the mold, it made it easier to do the cutouts.


As before, I used a Rondo gel-coat with about 50/50 Bondo/resin. The weather was warm (mid 80's F) so I kept the hardener a little on the "cold" side. Thin Rondo, then 6 cloth layers, then thick Rondo finish around the edges. I want to be able to sand down the edges to make a perfect fit to the main assembly.


You can see on the rough breakout the Radius side is a very nice fit, but the Ulna side does not sit down flat due to the thick edge and mainly the flashing. This will be trimmed off down to the final contour. Right now the whole thing is about 3mm too big on all sides. The surface edge trim will hide the groove ends.














I'm quite happy with the results.


More coming soon.


~ Vonnor

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I shaved the edges of the forearm plate down to a decent representation of the CG model's contours and added the raised edging. Had some slightly worse than moderate errors in the edge trim (as in broke it clean through) but will fix it a bit with filler and disguise it with the paint and weathering. The last pic shows the angle cut at the elbow to allow nose scratching and sandwich eating. :)


I found a reasonable solution to the metallic silver rectangles on the glove fingers. After much trial and error I tried inking them with a silver autograph marker and sealing them with Angelus matte finish acrylic sealer. Without the sealer the ink smudges very easily, but sealed it holds to the deerskin a lot better.


I also got some little neo-D magnets in the mail today that will power the gauntlet closure system.


More to come.







~ Vonnor

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oooo nice work ^_^ as of these pieces how much closer are you to completing this?

TODO: (from memory)

Cast left elbow guard mandrel

Cut-form L elbow guard

Build left gauntlet closure

Sculpt symmetrical wrist clip

Mold wrist clip

Cast wrist-clip hard model

Back-fill / contour wrist-clip

Mold/cast production wrist-clips

Final interior shaping / fitting for left wrist-clip

Build right gauntlet (about 20 steps)

Lose 30lbs

Build ab plate mandrel

Cut / shape ab plate

Build ab plate closure

Build torso cast

Sculpt back plate

Mold / cast back plate hard model (production piece?)

Sculpt chect plate / scapula plate (2-pc? 1-pc?)

Build / mount back box

Build torso armor closure

Build shirt

Rebuild pants

Determine belt-straps mounting / placement

Build strap / loinpad / hippad mounting

Build shoulder bell mounting

Build kama

Paint armor


Grow hair


Of these, only the last one is a certainty. ;)


Never build to a deadline, but always keep the end in sight.


~ Vonnor


EDIT: Forgot all the bandolier stuff, but you get the idea.

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