Don't like ads? Help support the Mercs by becoming a Supporter or Auxiliary Member today!
Official Members also get to use the forum ad-free - so kit up and join us!

 First bucket - Cold Cast Aluminum HIM

  • 16 Replies
  • 1788 Views

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
First bucket - Cold Cast Aluminum HIM
« on: Jul 15, 2020, 06:20 PM »
Su cuy'gar!
So I might have bitten off more than I can chew by going for a cold cast helmet right away, but it's here and so are the supplies I need, so here goes I guess...
I've got the helmet, 0000 steel wool, putty for the imperfections, a whole set of different sandpaper, a dremel tool to cut out the t-visor slot and polycarbonate and tint for the visor (need to figure out how to attach it).  I have some black paint and primer to use as a base, and some color samples to try. I'm not using the Paz Vizla antenna so I can use it for testing purposes I guess.

As far as I can figure from reading around the forums, I need to use the putty to fill out any voids or cracks, liberally polish with the 0000 steel wool (under running water?) to bring out the shine of the aluminum in the resin, and then spray with primer/paint?

Gaa'tayl ner Vode!

« Last Edit: Jul 24, 2020, 12:56 AM by LearRigh » Logged
Cabur Akaata #200

Grimstuff


    *
  • 75
  • Ayyy
Re: First bucket - Cold Cast Aluminum (I need guidance)
« Reply #1 on: Jul 15, 2020, 09:14 PM »
Yeah, looks like you've done your research well and have it handled. That's pretty much everything you need.


>liberally polish with the 0000 steel wool (under running water?) to bring out the shine of the aluminum in the resin, and then spray with primer/paint?

Doesn't necessarily need to be wet while polishing it, but yeah definitely at least give it a good bath scrub afterwards. Loose metallic powder makes for terrible adhesion for top-layers of paint.

And yep, I'd prime first for optimal adhesion. Optimally an automotive or metal primer, or even something like Rustoleum's Universal Bonding Primer. Metallics can be one of the more picky surfaces where adhesion is concerned.

Logged

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum (I need guidance)
« Reply #2 on: Jul 16, 2020, 10:56 PM »
Yeah, looks like you've done your research well and have it handled. That's pretty much everything you need.

Ok, good to know I'm in the right track at least.

I gave it an overall buff by hand with the 0000 for about 2 hours - basically until the one pad I was using fell apart completely.  A little shinier and a lot smoother, but not quite there yet.  I might try attaching the 0000 to my Dremel...


Logged
Cabur Akaata #200

Ori Dart


    *
  • *
  • *
  • 463
  • Just some random mir'sheb...
Re: First bucket - Cold Cast Aluminum (I need guidance)
« Reply #3 on: Jul 17, 2020, 09:09 AM »
Be careful about the buffing. A lot of helmets that are cold cast do not have a thick metallic layer, so taking too much material off kinda gets rid of the effect. I know it's time-consuming, but hand sanding is really the best way to do this.

Also, are you going to have most of the metallic bit exposed? If so, be sure you have your design planned out so that you don't cover all that hard work sanding with primer. ;)

Logged
Oya!

Andry         ; )

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum (I need guidance)
« Reply #4 on: Jul 17, 2020, 05:52 PM »
Be careful about the buffing. A lot of helmets that are cold cast do not have a thick metallic layer, so taking too much material off kinda gets rid of the effect. I know it's time-consuming, but hand sanding is really the best way to do this.

Yeah, I did some testing on the antenna piece that I'm not using and even the cloth buffing pad eats into it if you're not careful.  Reminded me that it's not an aluminum helmet, but a resin helmet with aluminum flakes in it.

Also, are you going to have most of the metallic bit exposed? If so, be sure you have your design planned out so that you don't cover all that hard work sanding with primer. ;)

The design is in my armor concept thread, link in my signature, but I'm going to have the raised visor surround be bare beskar.  I also want the shiny beskar to show through the damage and weathering to the paint (which I haven't planned out yet).  So you have a point that I don't need to get every little crevice to gleam, which is good.

Update:
I cut out the chin and eyeline of the t-visor, I left the mouth/nose area to reinforce the cheeks while I continue sanding. 


I started with a cutting wheel and scored a line across the middle, but it definitely did not have the clearance I needed, so I took Neomandalore's advice:
Iíve had more luck drilling a hole and using a cutting bit rather that a cutting wheel on a dremel. Just go slow and even, then do any clean up spots after
and used a cutting bit instead.  I did have a couple of slips, but they should buff out easily.


For the after clean up I used a bare hacksaw blade very slowly by hand to shave of the edges and cut at a consistent angle and get into the tight edges.  I'll still need to smooth out the sides and inside edges a bit, but I think it was a success overall!  I can't believe it's starting to come together

Logged
Cabur Akaata #200

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM
« Reply #5 on: Jul 19, 2020, 11:07 AM »
Ok, so I've gone through five of the eight 0000 steel wool pads in this pack and this thing has a nice dull gleam but it hasn't brightened up at all.  It looks more dark brushed aluminum than shiny aluminum.  I don't know if it's from the color of the resin or something I'm doing, but I can't get this thing to be shiny like I thought.  :'(

I tried to buff one side with a sample packet of Flitz polish paste that I had, and I didn't notice a difference after three or four applications and about an hour of buffing.

Flitz buffed side

Just 0000 sanding side

Should I risk a drill or dremel buffing attachment?
The cross section from the bottom edge leads me to believe that there is a good layer of the metal infused resin over the regular resin.



Would more applications of polish paste help at all?
It doesn't exactly have to be a mirror finish, but I thought with cold cast aluminum that I'd be able to get it mostly shiny with some hand sanding and polishing and I'm not sure if I'm doing this right...

Logged
Cabur Akaata #200

Grimstuff


    *
  • 75
  • Ayyy
Re: First bucket - Cold Cast Aluminum HIM (need help again)
« Reply #6 on: Jul 19, 2020, 04:19 PM »
Depending on the color of metallic dust they used, and the color of the resin that it was impregnated into, it may always be a little darker of a look no matter how much you buff it. Also just in general I've found that cold-casts do give a bit more of a dull iron look to things than the higher shines you can get via painted metallics, though I have seen people buff them into a super shine but they're definitely more patient and skilled than me.

Just for experimentation I'd probably try really power buffing a smaller area that you intend to top-coat anyway, and seeing how far you can push it before you either get your intended sheen, or reach the limit of how bright it can go (or buff through to the resin). From the results there you can judge how much work you want to put into the rest of the helmet. And yeah, might definitely be worth trying a powered polisher like a cloth dremel end or a dedicated buffing tool.

Also I wouldn't necessarily trust the bottom of the helmet to tell layer depth, as layers can shape weirdly there and/or powder may have simply built up. A place you've actually cut into the helmet would be best, like the edges of the visor.

Also also, be aware with polishing pastes that you'll need to take care to wash off any possible residue from those when you begin top-coating, as otherwise they may hurt adhesion significantly.

Logged

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM (need help again)
« Reply #7 on: Jul 20, 2020, 12:26 PM »
Ok, reassured and refocused, thanks Grim.

I'm taking a break: got a fiberglass pen and buffing stuff shipping, plus I'm working for the next two weeks.  Gotta remind myself that it's a marathon not a sprint.  I think cutting out the visor made me want to have it finished *NOW*, because I could actually see myself wearing it for the first time.

So I'll try out the buffing on the backside, which I'm for sure painting, and go from there.  In the mean time I'll go back to 3D modeling my armor (which I find relaxing) and planning out my soft parts.

Logged
Cabur Akaata #200

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM
« Reply #8 on: Jul 24, 2020, 01:51 AM »
I think I figured it out! 


I tested buffing the backside with Flitz and a drill buffer, which gave a nice "wet" polished look but did not improve the finish like I hoped it would.  So, having lost all hope, I mentally wrote off this helmet as a bad purchase and another lesson learned about impulse buying.

Since I didn't care anymore, I pulled out my small rasp files and went to town on all of the flat bits to straighten out the corners and edges.  I figured I could still paint the whole thing and at least get a decent first helmet out of it.  To my surprise, the rasp brought the aluminum luster right out.
I spent all evening filing just the rear vent and right ear piece, then decided to try the dome.  The rasp files weren't able to get a good consistent pattern, so I rummaged through my sandpaper kit and tried a bunch of different grades out.  320 grit, followed by 800 grit seems to work pretty well, and I'm thinking of using the 3000 grit and then the Flitz polish again after I get everything sanded smooth.



Now that my antennas are in, I have a choice to make:





My wife likes number 2, but 4 is growing on me.  Thoughts?

Logged
Cabur Akaata #200

Grimstuff


    *
  • 75
  • Ayyy
Re: First bucket - Cold Cast Aluminum HIM
« Reply #9 on: Jul 24, 2020, 04:11 PM »
Glad to see ya got it worked out. Sounds like his master sculpt was never quite smoothed enough before molding for the castings to be able to reach shine, but since you didn't sand through the metallic it sounds like he is using the thick application method of that, so at least you have a lot of freedom to work with it.

As for the antennas I can say that usually in real life you'd want them apart from each other so they wouldn't overload each other while transmitting, but of course it's a scifi prop so that's definitely not an actual limitation lol. You could also give em screw bases to make em interchangeable and arrange em however you feel on any given day.

Logged

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM
« Reply #10 on: Jul 24, 2020, 07:44 PM »
You could also give em screw bases to make em interchangeable and arrange em however you feel on any given day.

They actually come with a bunch of different screw bases (they're meant to be vanity car antennas), so that is an interesting idea.  If I was more tech savvy and had more time I could probably make them functional since they are real antennas.

Logged
Cabur Akaata #200

Grimstuff


    *
  • 75
  • Ayyy
Re: First bucket - Cold Cast Aluminum HIM
« Reply #11 on: Jul 25, 2020, 11:48 AM »
True yeah. At that size i'd assume they're SMA connections or something similar, should be pretty easy to find base mounts for em if so.

And yeah I was actually thinking about that real radio idea before once too when I was brainstorming an airsoft helm before, it's a pretty interesting build idea. There's a lot of super tiny FRS/GRMS radios I imagine one could rip the parts out of. Kinda just something that stays in the backburner of my brain until by chance I actually wanna try it someday.

Logged

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM
« Reply #12 on: Jul 27, 2020, 04:08 PM »
Incremental progress, might be my last post here until I start painting.  (Hopefully not too long)

I've done an overall sanding with 320 grit and then 800 grit.  I'll be doing another couple of rounds of sanding, and using my file set and potentially the needle file on my rotary tool to get all the nooks and crannies.


I did find a few areas that were thinly cast with the aluminum, unfortunately one is right where I had planned to have bare.


I'm relooking my paint scheme, and I'll work around it, but I'll still be able to use the bare base for the majority of the helmet.

Logged
Cabur Akaata #200

Grimstuff


    *
  • 75
  • Ayyy
Re: First bucket - Cold Cast Aluminum HIM
« Reply #13 on: Jul 28, 2020, 07:11 PM »
You can try touching areas like that up with a silver Sharpee. Rarely matches perfect to the surrounding metal, but you'll probably be the only one who notices it.

To hide it more though you could cut a bit of that area out with an xacto knife to look like chipped battle damage, then sharpee just that. Give the difference in metallic shades more visual explanation.

Logged

LearRigh


    *
  • *
  • 61
  • Ka'ramiit
Re: First bucket - Cold Cast Aluminum HIM
« Reply #14 on: Aug 02, 2020, 12:44 AM »
Progress update:

Probably 80% complete.  Still need to get into the corners, edges, and fine details.
Once I figure out where I want to leave bare I'll go over it with a super fine grit and then polish and buff.
I need to play around with paint schemes now.

Logged
Cabur Akaata #200
 


Don't like ads? Help support the Mercs by becoming a Supporter or Auxiliary Member today!
Official Members also get to use the forum ad-free - so kit up and join us!




Powered by EzPortal