Pages

Saturday, April 16, 2011

Sanding made easy

I love making beads out of polymer clay.  But trying to get them to look as shiny as polished glass seemed to be rather difficult.  Regardless of whether you went the route of using some sort of resin or glaze, first and foremost you needed to sand.  and sand.  and sand again.  Going through progressivly finer grits of sand paper to achieve a smooth finish before buffing.  The time involved can be disheartening especially if you are trying to turn your hobby into a thriving business.  The more time spent making an item the more you need to charge for it.  And if you're not careful you can price yourself right out of sales!  Unless you are willing to work for free, and you can't support yourself doing that, you need to find ways to cut your production time without sacrificing your quality.

The beads in the above picture were buffed to a glassy shine after being sanded for 3 straight days, through various grits of abrasive in a ROCK TUMBLER!  I can't tell you what a great job it did on the sanding.  One important thing to note was how well it worked on beads that had nooks and crannies that are normally difficult to get into with a piece of wet/dry sand paper.  In addition, NO hand cramping.  Yeah!


This clay bead has been twisted creating deep indentations that are normally hard to get into with regular wet/dry sand paper.  But the fine grained silicon carbide grit easily gets into all the nooks and crannies.

I checked on the beads progress each day.  I was anxious to see how they would turn out while at the same time worried I could be ruining all my hard work.  I tend towards impatience.  But,I'm working on it.  The first stage called 'first grind' is for stones that are still rough with jagged edges so I skipped that and started with what is referred to as the 'second grind' with the medium grit abrasive.  After about 1 1/2 days moved on to the 'pre-polish' stage for an additional 1 1/2 days.  I pulled the beads (top photo) and buffed them after completing the 'pre-polish' stage.  I put the rest back in the tumbler with the polishing compound.  When tumbling rocks this would be a 5-7 days process, but as I said I'm impatient so I only lasted 1 1/2 days before pulling them.  According to the directions (for rocks) they should look the same dry as they do wet (mine don't).  If not, they need to tumble longer.  If they have a slight film (mine do) they need to be burnished.  I wish I had let them go longer.  But I'll try that next time.

For now, the beads I pulled after the 'pre-polish' stage got a beautiful gloss with buffing (top pic).  But I'd like to see if the buffing time could be reduced a little more by letting them tumble longer.  As for the beads that went through the somewhat abreviated polishing stage they do have a slight film on them which reminds me of a milk.
If you look on the lower left of the bead you can see where it has been lightly buffed.
The upper right still has the milky white film from the polishing compound.

This photo shows how cloudy the bead is directly from the polishing stage after rinsing and drying.
This bead will need burnishing to remove the film.
 To burnish the beads they need to be tumbled with powdered soap like Ivory or White King.  This step according to the directions will take 4 days.  So I will come back and let you know how that turns out.

To give you an idea of how much clay you could tumble/sand at one time see this photo below.  I only had the tumber about 1/2 full.  Instructions recommend filling at least 1/2 to 3/4 full.

The above photo has 145 various sized beads.  Having paid $12.99 for the grit pack thats a cost of $ .09 per bead.  And the tumbler still had room for yet another 1/2 - 2/3 cup more beads for even greater savings!  That is pretty cost effective.  Especially when you add in the fact that instead of sanding all those beads by hand I was able to work on creating something else! (the beads on the bottom and on the left have already been buffed)
For those that are interested; the rock tumber I used was a 3lb capacity rotary rock tumbler.  Check your local Craft or Hobby store or the links on this page.  For those that want to double their production time the tumbler is available in a dual drum style as well.  You can have beads at 2 different stages going at the same time.

Drop me a line if you try this and let me know how it worked for you.

Thanks for stopping by,

Judy

UPDATE 04/22/2011

For now I am only recommending tumbling for several days with the medium grit abrasive and then several days in the pre-polish stage.  I DO NOT yet suggest anyone do the polish stage yet.  That step is still very much a work in progress!  As I said above, mine did have a milky white film coating the beads which according to the directions meant I then needed to do the burnishing step.

The top row of beads were buffed after completing the pre-polish stage.  The bottom bead went through the polish stage which resulted in a white film coating I haven't been able to remove yet.  Until I figure that out I am NOT recommending that anyone do the polish stage.
I did the burnishing step (tumbling with powdered soap) for 4 days and still have the white film on my beads.  Look at the bottom bead in the above photo compared to the twist bead right above it.   The burnishing directions recommended a 'powdered soap such as Ivory or White King'.  I didn't find either those at the store and picked up another brand.  Whether that deviation is what caused the problem, I'm not sure.

Texturally you can't feel the film.  The bead simply feels like it was nicely sanded.  But the film discolors the bead.   All my wonderful white beads with the beautiful bright colored speckles are now more of a vanilla ice cream color.  The color specks however don't look any different.  Don't get me wrong the vanilla color is pretty but I want my white back!


All 4 beads have been through the polish stage
and came out yellowed.
The bottom left bead was buffed until the film
was gone and the white returned.

These beads were pulled after the pre-polish stage.
The bead on the right was then buffed.

 As it stands I would not proceed past the pre-polish stage.  As you can see in the very fist photo of this article buffing them after the pre-polish stage brought out a beautiful glassy shine so for now I would stop there.  The amount of time its taking to buff off that layer of film is too much.  In addition, there is a very fine line regarding the amount of pressure needed to remove the film.  Too much pressure and you will create flat spots instead of a smooth shine.

Another problem is that the film isn't always that noticable.  The film itself will gloss up to a beautiful shine so you may not realize that you still haven't buffed all of that film off.  I kept looking at the bead on the bottom right, asking myself "did I make beads that looked like that?" The effect isn't necessarily unattactive, but it wasn't what I wanted.  If you look at the bottom middle of the right bead you can see where I have buffed enough of the film off that the color is starting to show through.
So for now, 100% YES to using the rock tumbler for sanding and pre-polish.  But I would hold off on the actual polish stage unless you would like to experiment with the soft muted color effects.


Please let me know the results you have if you try this.

Judy


UPDATE 05/06/11

I picked up some Arm and Hammer washing soda and reburnished the beads for 2-3 days and the white film seemed to have faded a little.

I lightly re-sanded the beads with 1000 grit wet/dry sandpaper.  My white beads that were sort of a vanilla color came back to the white and then I buffed them all and the shine is amazing!

Even though sanding off the film and then buffing created an amazing shine, it was more time intensive than I would like.  So for now I would still skip the polish stage.  But I would increase the time spent on the sanding and pre-polish stage to maybe 3 days a piece.

The photos do not do justice to the amazing shine on these beads.  In person they almost look 'wet'.  Like they've been triple glazed!
Take care!
Judy