How to sand the borders of acrylic

[PedroSilva]

Hi,

Here I am again for another question for you "experts" on the subject ...

I'm going to cover my Cp with an acrylic (believe you guys call it plexiglass) sheet 2mm thickness.

For the cutting / driling no problem ... I'l use metal apropriate.

The quesion is ... How or what should I use to make the borders smoth and kinda round without scratching it ?

Does metal sand papper 600 grain do the trick ?

Thanks

[Infrasonic]

I would only sand using a sanding block, with the sandpaper fastened tightly onto it.  Also, it would probably be best to keep the protective plastic, and/or using masking tape to protect the area around the edges.  Using 600 may prove tedious, you could try starting with a coarser grade-like or 220, and move up to 600.  Remember acrylic is brittle and can break easily.  It has better scratch resistance that polycarbonate though, and is cheaper.  Sanding with water-wet wet/dry sandpaper is best.  

[Tailgunner]

Heat works nicely. Try a propane torch on a piece of scrap, you just need to get it hot enough that the sharp edges melt and round themselves. Too hot and the acrylic will bubble or warp. With a little practice you'll find the right amount of heat to round the edges quickly and cleanly.

[Zakk]

Only way I know of to get a real smooth finish is the buffing wheel.  Also takes a little bit of trial and error to get used to, but then it's a piece of cake:

http://www.mameworld.net/massive/How-to/Buff/buffing.htm

[Infrasonic]

Be careful with that torch, acrylic is inflammable.

[RandyT]

Be careful with that torch, acrylic is inflammable.

True, but don't let that stand in your way.  

The pros flame-polish acrylic.  Just be careful, practice and take your time.

RandyT

[PedroSilva]

Hi,

Thank you all for the great ideas ... this is why I love this forum .. there's always someone who has already had and solved all my problems ...  

Regarding the choice ... I think I'll try to use the suggestion from Zakk ... it's exacly that finish I'm looking ...

Last question:
Is there anything we can adapt to the power drill to do the job ? I don't want to by a buffing wheel just to do that.

Thanks

[Infrasonic]

you could use a file - I use files, it really doesn't matter what type of file you use double cut, single cut, or double-bastard.  

My main purpose is to remove the sharp edges.  It takes me about a minute and it's done.  

[PedroSilva]

you could use a file - I use files, it really doesn't matter what type of file you use double cut, single cut, or double-bastard.  

My main purpose is to remove the sharp edges.  It takes me about a minute and it's done.  

What's a file ?  

[Infrasonic]

here's a pic

[PedroSilva]

I see ...

But with that you have to have a very good eye to maintain the same angle all along ...  

I'll make the test anyway ...

Thanks,

[neuromancer]

Files are good for the bulk of the work.

The problem with any mechanical sander is heat buildup melts the plastic, which gets gooey.

Buffing plastic with a wheel is tedious too. It's really easy to press the material too hard into the wheel and melt it.

This is something you want to practice a lot before you try it out.

I don't think your drill press is going to spin any where near fast enough to work as a buffing wheel.

Bob

[neuromancer]

Files are good for the bulk of the work.

The problem with any mechanical sander is heat buildup melts the plastic, which gets gooey.

Buffing plastic with a wheel is tedious too. It's really easy to press the material too hard into the wheel and melt it.

This is something you want to practice a lot before you try it out.

I don't think your drill press is going to spin any where near fast enough to work as a buffing wheel.

Bob

[PedroSilva]

Files are good for the bulk of the work.

The problem with any mechanical sander is heat buildup melts the plastic, which gets gooey.

Buffing plastic with a wheel is tedious too. It's really easy to press the material too hard into the wheel and melt it.

This is something you want to practice a lot before you try it out.

I don't think your drill press is going to spin any where near fast enough to work as a buffing wheel.

Bob

Damn ...
I'll have to spend more money

Gonna have to stop eating to balance ...