Showing posts with label Signs. Show all posts
Showing posts with label Signs. Show all posts

07 February, 2013

Hitman Badge for Agent 47

An airsofting friend was on the lookout for a metal hitman badge to adorn his aluminium sniper rifle case.

A good look around the bowels of the internet drew a blank. He couldn't source such a thing. I had been thinking about using MDF as one time moulds for pewter casting and wanted to see what could be achieved, so I thought this might be a nice experiment.

In case you have been on the off-world colonies for the past decade or so, you have missed the video game series that is Hitman.

The game revolves around Agent 47 who unsurprisingly goes around killing people, often with a sniper rifle. So last Halloween, a local airsofting field had a fancy dress charity airsoft event, and my friend came as a very convincing Agent 47. Being the kind of guy who likes detail, he wanted the badge to complete his rifle case.



So the first job is to reproduce this as a vector image, which I built in Solid Edged 2D drafting, turn it into G-code tool paths and load the G-code into EMC2 on my Ubuntu box. I've discussed that in previous posts, so I won't go into that all again here...

The logo loaded into EMC2
Then shape it is thencutout with a 1.9mm endmil in MDF on my CNC router. MDF cuts a bit 'hairy' so I burn off these hairy fibres with a cigarette lighter to clean up the mould which would otherwise be very difficult to sand...

The finished MDF mould
Then with a back piece added to the mould, the molten pewter is cast into it...

Casting the badge
After a cool-down the part is demoulded...

Removing the part from the mould
Here is the badge completely demoulded with the ingate and outgate still attached...

Quite rough, I think!
Before casting I had liberally dusted the mould with baby powder to aid with demoulding. In the end the part came away very easily.

I cut off the ingate and outgate with a hacksaw.

Sanding down the front face with progressively finer wet and dry paper, polishes up the raised areas to a nice finish...

Finished! The tape measure is for scale.
Using P80, P180 and then P280 and a lot of elbow grease brought the face up to a nice smooth satin sheen.

Noticed the deliberate mistake yet? (scroll down)
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I forgot to horizontally flip the image, so it is not correct. Not to worry pewter can be remelted. As I write I am currently cutting the mirror image of this on the CNC router and will recast and post the images here.

Doh!

Update:

I recut the mould in the correct orientation, not in MDF this time but in maple, and the difference is significant. The maple mould required much less finishing and the piece made is of finer quality.

Below you can see the MDF cast piece on the left and the maple cast piece on the right.

Left bad, right good! Note the cleaner edges too!
 During all that hand finishing I actually sanded three of my fingers, which now have distinctly flat sides. You would think I would notice then pain, but I was too engrossed in working on the piece. Only when I saw blood did I think there might be a problem. Doctors say I might just pull thorough! ;)



To finish off, here is a movie of the two pieces catching the light...



I have sprayed the correct piece matt black then I will sand it again to reveal the raised areas in bare metal. Then it is finished!


photo courtesy G Mason. (click image to zoom)
I'm quite happy with the result, hopefully he will be too. As an experiment I thought it worked well, but maple definitely makes a better mould than MDF. Maybe I will make my beloved something for Valentines Day using this technique, but what? I better get my finger out, Valentines Day only one week away!

Thanks for reading! :D Feel free to comment here.

11 January, 2013

Airsoft Range Signs

2013 is here already and sees me making a few minimum engagement range signs for a local airsoft field. Minimum engagement distances always seem to be a source of friction. With these signs set up on the firing range, noobs and vets alike can familiarise themselves with what those distances look like in reality, rather than being purely abstract.

Cutting the full auto sign on the CNC router.
The signs are fairly close to the maximum size that I can cut in a single piece on my CNC router. They measure 400x400mm, that's approximately 16 inches square in old money. You can see my control computer in the top left of this photo.

Some burning of the lettering due to a blunt (cheap) endmill.
 I used a V profile endmill that came with a cheap 800w router that I bought from a DIY superstore. Even though it was brand new and factory sharp, you can see that by the green sign it was already beginning to burn the plywood. They will be outdoors all year around so the charring will weather off, so i am not so concerned with it.

A few more, including mustering instructions for the red and blue teams.
 For the last few signs I switched to a better quality ball endmill that I bought in Ace hardware. Note the cleaner cut.

These minimum engagement distances are for airsoft weapons powered between 328 and 350fps. This is the most common power band on the site.