Mythbusters!!!

[Ian_Gere]

Can acrylic be milled in such a way that the scratches don't make the surface translucent rather than transparent? Because to see yaw in the angle of backspin would need good transparency, i think.

[proffrink]

3D print or CNC some cheap plastic inversion of the two halves of the body then vacuum-form it - wouldn't cost too much and could be done with acrylic quite readily.

[Colonel Kurtz]

Can acrylic be milled in such a way that the scratches don't make the surface translucent rather than transparent? Because to see yaw in the angle of backspin would need good transparency, i think.

 

Wow I never thought my 6 months working in a plastic factory (mostly thermosetting) as a kid would have any use/relevance in later life.

 

The milling will indeed leave it rough and not see-through, 3D printing would be much worse/rougher. You can make it transparent again with combinations of buffing/polishing/heat-treatment/solvent, but it'll be painstaking to do if your just using a standard milling machine and a block of standard acrylic, and easy to ruin. Another concern is if your are doing it in one-man-and-his-workshop fashion, then the milling process can warp the acrylic due to heat. (not its shape, but consistency so it's cloudy/wavy inside). The milling machines at the factory i worked at had massive cooling setups to keep things at specific temperatures, tailored to the compound (which was also tailored to the task)

 

In my time working there, I mostly did finishing on BP garage signs. There's one out there in the UK somewhere which has a delightful sketch of an oil-barrel with a penis f*cking a whale scratched into it, and a couple with a standard 'woz ere'.

[Ian_Gere]

How about glass for the barrel? Some kind of heat treated chemistry stylee kit maybee?

Edited September 10, 2015 by Ian_Gere
not easily shattered crap

[NickM]

You can get some really nice glass rods and glass tubing for making scientific equipment. I'll have a word with our technicians and find out if a slightly larger than 6mm diameter is available. Its fairly easy to work but I would be curious if a bb fired down it might cause it to crack.

[Preston]

Can acrylic be milled in such a way that the scratches don't make the surface translucent rather than transparent? Because to see yaw in the angle of backspin would need good transparency, i think.

It is possible, at work I deal with acrylic more than I like to. A good cooling system is required. Ours is air cooled, most engineering millers will be liquid cooled. Special acrylic milling bits can be bought which leave a better finish than a standard bit would leave, or a diamond bit can be used to leave a pretty much clear finish. We use flam polishing on any acrylic we cut but this is not ideal for something like a gear box, due to small holes and tolerances. The heat would warp it all. A chemical dip would be better.

[n1ckh]

You could mould the items using liquid acrylic

 

Make up the mould from rubber then pour in the acrylic, the same can be done with the barrel, that way it's just the outside that would need a polish to make it see through again

 

Plus with the mould, you can have the barrel window already done or have a slight indent to show where the window is

 

You can use all exsisting parts as the pattern for what needs to be done

[ImTriggerHappy]

You could mould the items using liquid acrylic

 

Make up the mould from rubber then pour in the acrylic, the same can be done with the barrel, that way it's just the outside that would need a polish to make it see through again

 

Plus with the mould, you can have the barrel window already done or have a slight indent to show where the window is

 

You can use all exsisting parts as the pattern for what needs to be done

Crack on then.

[n1ckh]

Crack on then.

 

I'll need a word with my mate as I've never done it but you never know lol

[NickM]

Upshot of my discussions with the technicians, glass tubing comes in a variety of sizes but there are a few different types of glass and getting the right one is important, it seemed one is better with heat, one is better for impact and they didn't know which was which. They are sold with internal diameters but they tend to be dead on the mm, so 6mm or 7mm would be available. I guess with a set of digital callipers you might be able to pick one out of a batch that would work but there would be no guarantees that the diameter would stay consistent all the way through. The final issue would be cutting the hop window, with a diamond dremmel wheel might be a good idea but you could end up shattering the tube.