INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

Surface Finish for Light Pipe Diffused Exit surface??

Surface Finish for Light Pipe Diffused Exit surface??

(OP)
Before someone tries to moderate and shut this thread down like another one that was asking the same question, which was never answered, I also would like to know what a good finish is for light pipe diffused exit surface.

I read all the link on the other thread and didn't find a specific answer to the question. It looks like the polished part of the body would do well with a SPI-A2 finish, but need to find the diffuser exit surface finish.

Try worrying less about moderating and sending people off to areas with vague answers than letting them discuss and share information they are having a hard time finding. If I could find it I wouldn't be here asking.

RE: Surface Finish for Light Pipe Diffused Exit surface??

I'm not sure why you are so upset; but if there are no replies to a thread in 6 months, the thread is automatically closed. Perhaps this is what happened to the other thread.

Anyway, if you are only looking to diffuse the light, pretty much any light (no pun intended) texture will do. If you are looking to achieve a certain effect, perhaps small concentric ribs or a faceted surface would do better.

RE: Surface Finish for Light Pipe Diffused Exit surface??

(OP)
Thanks, am not upset, but the first response on the other thread was someone moderating them. Am looking for someone who has actually designed a light pipe to give me some guidance.

RE: Surface Finish for Light Pipe Diffused Exit surface??

I've tried milling ribs in an acrylic prototype, but it didn't work very well; you'd need to go to very fine geometry.
... which is more easily achieved with sandpaper.
... which you pretty much have to do by hand, because fast-moving sandpaper just melts plastic.

Separately, I tried refinishing plastic headlamp lenses with a $25 3M kit and a battery powered drill.
The drill was slow enough that the plastic didn't melt.
The first part of the process involves a disc that I think is about 600 grit, and fairly special, in that it didn't clog easily, even when used dry as instructed.
When that was done, the lens appeared to be opaque white; i.e., the surface was very diffuse.

(The second step involved a much finer grit and water, and the end result was spectacular; no other headlamp refinish kit I've tried worked nearly as fast or as well as the 3M kit.)


Mike Halloran
Pembroke Pines, FL, USA

RE: Surface Finish for Light Pipe Diffused Exit surface??

If it's the thread from 2008, the OP was told that double-posting wasn't allowed (new posters tend to spam multiple forums to get their question answered). Try not to admonish the folks here for things you think they might do to you, particularly if they haven't done it... it sets a poor tone for the following discussion.

If you want a diffuse surface, I would expect an A2 to be too polished... I'd shoot for something closer to a B1/B2.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Surface Finish for Light Pipe Diffused Exit surface??

You would be best off getting some acrylic rod and simply experimenting with different finishes.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close