Frosting clear test tubes - suggestions?

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

halforc80

New Member
Hi all,
Fairly simply question I hope; I'm using some plastic/acrylic test tubes in a build and want to defuse LED light through them, which I'm hoping frosting the plastic inside the tube will achieve. While I can find loads of advice on frosting clear plastic sheets, I'm at a loss as to how to frost the inside of plastic tubes...

Any ideas, oh model builder massive? :)
 

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

who45

Well-Known Member
if there plastic some wet and dry paper would give a frosted look and be smooth on the fingers - i used this technique on a clear block of perspex as i needed to frost it - it worked a treat - so sanding down the exterior of the tube should give the same effect

think i used 400 and 800 grit paper and to really smooth the finish i hit it with 1200
 

robn1

Master Member
If you want to frost the inside, try clear flat paint. Or sand/media blasting if you have the equipment. But if it's the inside clear flat will do, and can't be rubbed off from outside.
 

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

robn1

Master Member
Spraying the inside would be difficult. Use a bottled clear flat like Tamiya. Pour some into the tube and swirl it around until the whole inside is coated. Then pour out the extra. You can do multiple coats until you get the level of frosting you want.
 

halforc80

New Member
Cheers all!
I've got a bunch of tubes, so I'll experiment with both sanding and the clear flat paint method. Hopefully, I'll get a good effect from one of them and a good defusion of light leading to a nice glow afterwards! :D
 

Gigatron

Sr Member
Get a long, wooden dowel, smaller than the inside diameter of the tube (but only by a few fractions of an inch). Spray the dowel with spray adhesive (some 3M 77 should do well) and attach sheets of sandpaper (rubberband them on, overnight, to get good ahesion). Chuck a decent sized bit into your power drill and drill into the dowel - voila, instant, powered sanding rod.

-Fred
 

Scratchy

Sr Member
I have a small hobby sand blaster, the size of an airbrush. It would certainly do the job. If I can just find some way of passing it through this computer screen to you, then your problems would be solved.
 

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

T2SF

Well-Known Member
It will leave an uneven/ non uniform finish, I would try 600+ grit sand paper but perhaps do a test of different tricks ;)
 

Darkside

Well-Known Member
can you test a small piece with acetone?
i reacts with surface and could give this effect, if the material is strong enough it wont be cracked or destroyed. but a dilute solution (in grain alcohol or methanol) could do it.
 

Jayn

Sr Member
if it's straight sided , maybe a piece of vellum/tracing paper, or theatrical diffusion gel cut to fit the inside? that would work if there's no round bottom to the tube..
 

Scratchy

Sr Member
Why not try pouring a bottle of liquid cement into the test tube, then pour it back into the glue jar. This stuff fogs plastic windshields on models, .... why not make it the technique to frost the acrylic test tube?
 

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

Don't want to see this ad? Sign up for anRPF Premium Membershiptoday. Support the community. Stop the ads.

Top