Acrylic questions

[QuiltinMom]

I am new to pen turning and have turned a couple of pieces of acrylic and I have some questions.

I have seen some drill bits for acrylic. Does anyone use these and are they necessary? Is there a better success rate of drilling the blanks if you use these?

Also, what do you use to sand and finish the acrylic? I purchased a plastic sanding kit with 3 different sanding pads in it and some polish. Is this what is recommended or is there a better option?

I am struggling getting the acrylic real smooth. It seems to still have sanding marks in it after a lot of effort. I turned a secret compartment key chain and tried putting some beads on it. I had trouble getting down in between the beads to sand it without leaving unwanted marks.

Any help or suggestions would be appreciated. I am so intrigued with acrylic that we have ordered supplies to try and pour some of our own. Can't wait for all of the goodies to arrive and give it a try.

 

[Leatherman1998]

Usings a nagative rake scraper might help with the surface problems, a plain drill bit will work fine, using a bradpoint bit is asking for trouble IMO. I always wet sand on plastics around 500-700 rpms, then use polish. Standard automotive headlight polish works really well.

Just my .02

Levi Woodard
Sent from my Galaxy tab 3 using Forum Runner

 

[Akula]

Don't skip any grade of sandpaper...let the paper do the work..ie, don't press hard and keep it moving so you don't build up heat

I start at 400 go up to 600, then MM and polish using white diamond on a buffing wheel. The cleaner your cuts the higher grade you can start.

Lot of different ways, test them out until you find what you like best. Many don't like the sanding but I do and have no problem spending more time. I find it relaxing LOL

 

[avbill]

If you are seeing sanding marks Go back and resand: Don't skip any grade of sandpaper..
Then sanding you do not need high speed. lower your speed. DO NOT APPLY pressure then sanding allow the paper to do the work. Stop the lathe and sand the length of blank. at 90 degrees to the first sanding.

There are many ways to do sanding & then polishing the blank. I wet sand & polish the acrylic blank. Then using MM ( micro mesh sandpaper ) I double even triple the time with every grade higher to 12,000 grit. I then take to the bluffing wheel with 5 other smaller micron grit compounds. Many will say Its not necessary -- Yet fellow turner look at my pens and ask how do you get it so elegant.

Any master turner will always evaluate his/her finished product and ask how can I do it better? Your best way is to practice, practice, and practice. Just take a blank 20mm round and sand, then polish it. then do it again, and again! Master the technique!

 

[ashaw]

Besure important all sanding is done wet. After sanding with paper and mm. Put it on a buffer. It took me about two years to ready handle resins. Take your time and practice. I got the handle of it back in 2004. This was before all of the tools that came out. Also use the pen pro. That one tool changed the way I work in a great way.

 

[edstreet]

Not all acrylic's are the same, this is where most people run into epic problems at. The number of grits needed depends on the hardness of the material.

The Smoothness issue could be a great number of things and it's impossible to say for any certainty with out a close inspection of the blank.

 

[tangoman]

Finishing

G'day QuiltinMom,

I recommend checking out the library section of this wonderful forum. More useful information than we'll ever need !!

Regards and Welcome,
Cam

 

[navycop]

The micro mesh pads work good. Use them wet and go thru all the grits. Make sure you sand lenghtwise after to remove sand marks. if you put a wooden piece under the blank to prevent blow out.

 

[dankc908]

After I sand, with the running lathe, I turn the lathe off and sand 'horizontally' while hand turning the lathe/blank, after EACH grit. This has virtually eliminated any sanding marks. I do 'wet sanding' with my sanding pads (PKFINKIT). This has worked great for me.

 

[walshjp17]

What everyone has said. As for the beads, just fold the sanding medium in half to form a sharp-ish edge and then sand between the beads. Remember LIGHT pressure.