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microburt
28-07-2010, 06:38 PM
Hello all

I am hacing a few sanding probs and I wondered if anyone can help.

I have got wet/ dry sandpaper ranging from 340 to 2000 grit. After backing, I worked on each bead starting with the lowest and working up to the highest, using wet paper. However, as my beads dried they started looking dull and looked like they had a white residue on them. I washed them and buffed them but no joy.

Any ideas what I 'm doing wrong? I am hand sanding.

Thanks!

Amanda xx

Nihal Erpeden
28-07-2010, 08:36 PM
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Hazer
28-07-2010, 08:39 PM
I was with you until you said the residue wouldn't wash off...I've often had white dusty residue on my beads, but it always comes off after a rub with a washcloth. The only thing I can think to suggest is to make sure you've included a little dish soap or washing-up liquid in with your water to stop the sandpaper clogging with polymer clay, which may be working its way into the surface of your beads.

Hopefully Emma will be along soon with a proper answer :D

Bev478
29-07-2010, 12:05 AM
I washed them and buffed them but no joy.

Any ideas what I 'm doing wrong? I am hand sanding.

Thanks!

Amanda xxWhen you say no joy - what is the end result you are after? If it's a high gloss you may be able to buff them enough (preferably by mechanical means) to achieve this. Personally I find life is too short & prefer to use a gloss varnish!

When you use wet 'n' dry on anything it will leave a residue, which should wash off. This is not to be confused with the slightly dull finish which rubbing down will give. This should improve as you work your way through the grades tho.

krielj
29-07-2010, 11:12 AM
I agree with the others. It should definitely come off with a wash and some rubbing with a soft cloth. I start with 800 grit and then go to 1200 grit. Then I give the beads a wash with some warm soapy water and then I rub them hard with a dry cloth. Then you can either leave them like that for a natural finish or polish them (I have a felt wheel on a small bench grinder and they come up like glass!).

microburt
29-07-2010, 12:10 PM
Thanks all! I spent some time doing some serious buffing (on my jeans during the journey from Germany to the UK!) and eventually it all came off and I am pleased with the finish- it's kind of like satin! Thanks all for advice. xxx

ejralph
02-08-2010, 09:46 AM
You might just be starting with too coarse a sandpaper.

A 340 grit is quite coarse for polymer clay - it means you could gouge deeper scratches into the clay than you think with the first sanding and the residue might be getting trapped in these, hence not washing away easily.

The key with wet sanding is to have a drop of detergent in with the water - only a drop mind, and that should be enough to keep the sandpaper and the clay pretty clean.

Don't spend too long on each grit - use your judgement, but after a while remember you won't be making anything smoother, just smaller!

The best thing is to always get the clay as smooth as possible before baking. Then you shouldn't really need to start with a paper any coarse than around 600 grit.

I tend to start with a 600 grit, then go straight to a 1200 grit. Rarely will I go higher. It just doesn't seem to need it if you get the beads as smooth as possible first.

The only time I may need a coarser paper is if I deliberate need to remove a lot of clay - say if I have used two colours of clay and need to sand off the outer colour on high areas to reveal the second colour. Even then I start at about 400.

I think Bev is probably right in that what you are seeing is mostly the natural look of polymer clay when it has been sanded. I think also maybe there could be deeper cracks from the coarse paper that have filled with fine polymer clay powder - so you don't necessarily notice them when you run your finger over the clay. And I expect this is what is causing the residue look.

The only other idea - is something that can happen with mokume gane beads, made with foils. Sometimes (and I have only seen it rarely) the water can get in between the layers of clay and give the clay a cloudy appearance. Doesn't look like a residue though, just a cloudyness of the clay. So if you have made layed Mokume Gane beads with foils, this could be worth considering?

My money is on the coarse sandpaper though - whenever I have used paper this coarse, it has been a bugger to get the clay TRUELY smooth after and get those deep gouges out and they do make the clay look matte and white.

Emma

microburt
09-08-2010, 01:47 PM
Emma you are a star. I was starting with 320 and the clay was already smooth ish. I think i'm gonna start at 600 in future. I've just started using kato clay and have written about it in a separate thread. Have you tried it? I love it! X

ejralph
10-08-2010, 08:56 AM
Emma you are a star. I was starting with 320 and the clay was already smooth ish. I think i'm gonna start at 600 in future. I've just started using kato clay and have written about it in a separate thread. Have you tried it? I love it! X

Glad I could help Amanda

Yes, I have tried Kato clay (I don't think there is a clay brand out there I haven't tried at some point over the years - lol). I like the way Kato handles, even if it is a bugger to condition. What I couldn't handle was the smell - it gives me terrible headaches / sinus problems. I also find that with all the American brands of clay, I don't like the overly "plastic-ey" look to the baked finish. But that is just my opinion of course - many people adore Kato clay and it is a very popular brand.

For me though, I defintely prefer the European brands. But it all goes to show - there really is no one best brand of polymer clay, different people like different things and its only by trying them all out that you can find your own personal favourite.

Emma

microburt
12-08-2010, 08:44 AM
Glad I could help Amanda

Yes, I have tried Kato clay (I don't think there is a clay brand out there I haven't tried at some point over the years - lol). I like the way Kato handles, even if it is a bugger to condition. What I couldn't handle was the smell - it gives me terrible headaches / sinus problems. I also find that with all the American brands of clay, I don't like the overly "plastic-ey" look to the baked finish. But that is just my opinion of course - many people adore Kato clay and it is a very popular brand.

For me though, I defintely prefer the European brands. But it all goes to show - there really is no one best brand of polymer clay, different people like different things and its only by trying them all out that you can find your own personal favourite.

Emma

The smell is quite strong! I am going to use Kato and also Cernit which I think I prefer to Fimo...

A x