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Surface questions

Posted: Fri Jul 04, 2003 9:41 am
by Jackie Beckman
OK, I need some help. This is one of those times when an experiment of my own would be the best, but running short on time, so if someone else knows . . .

During the second firing of my recent work I fire face down (on thinfire) - I like the crisp edges and the entire look face-down gives me much better for my current pieces. If the pieces will fit on my clay shelves, I prefer those, as they are flatter than my fiber shelves. If they are larger than a 20" square, I use fiber shelves. Up until now, after this firing I sandblast the entire surface, and sometimes carve it, then either firepolish or oil depending on the look I'm after.

A couple days ago I started playing with grinding? sanding? polishing? disks. I have been doing the entire surface starting at 50 grit and going up to either 800 or 1500. I really love the smoooooth surface I've been getting. But . . . the look I want is matte, and smooth and naturally - swirl free. Not so easy.

When I get up to 1500 I have the smoothness and the matte finish I like, but there are still swirl marks. I tried to oil at that point, and it does take away the swirl marks, but it makes it too shiney, AND there isn't enough tooth to allow the oil to sink in the way it does on a blasted surface. So - no good.

Then I sandblasted the 1500 surface lightly. This gave me a much smoother look than when I just sandblast a piece right out of the kiln, yet its not that "touch-me" smoothness I was really after. It does however allow the oil to sink in nicely and it has a nice matte finish, so better than the previous method.

Next, I tried to go up to 800 and fire polish very low - (1175) and I'm still waiting to see how that comes out.

So - question one: What to try next? Remember, I'm looking for smooooooth, matte, and swirl free. Anyone? (Steve Klein, if you're out there - help?)

Question two: When I fire the pieces face down on the fiber shelf rather than mullite, even though I use thin fire, the time I spend with the 50 grit is amazingly longer. I mean - FOREVER! This is because of the surface of the fiber board. Lots more of the little low spots that I never noticed when I was just blasting them. So - I thought what I may need to do is after the piece has been fired face down, giving me the look I like, perhaps I need to flip it over and fire it face up, THEN start with the disks. That would probably even the surface out enough that I wouldn't have to spend so much time with the 50 grit. But, would it change the look I acheived by firing face down in the first place? That's the part I can't forsee. I really like the look of the pieces when they are fired face down, and if I must spend forever with 50 grit, so be it. But - if I can flip and fire to even out the surface without loosing the look of the face-down firing, then that would be the ticket. Anyone know?

No-time-for-BBQs-and-fireworks-Girl

Posted: Fri Jul 04, 2003 10:13 am
by rodney
ON GETTING RID OF THE SWIRLS

perhaps there is a palm sander that only goes back and forth and not as a swirl, if not, you could use a belt sander with the water paper, you would have to spritz the glass with water, and avoid getting water in the motor, but this could work

rodney

Posted: Fri Jul 04, 2003 10:19 am
by rodney
ON THE UNEVEN FIBER SHELF
what you can do here is take the fiber shelf, all the time wearing a proper dust mask, etc,,,,,and get the belt sander, with a fine grit paper and smooth it out, once this is done, soak it with the RIGIDIZER, once it dries, go back, with a fine grit paper and sand it again,,,you may wish to put somemore rigidizer on it, but one time will probably work, hope this works

rodney

Posted: Fri Jul 04, 2003 11:35 am
by Barbara Muth
Jackie, if what you like when firing face down is the crispness of the lines, flipping it shouldn't change that. I often do that. But, I have on occassion gotten clouding in a transparent surface when I did that. Don't know what that would do to an opal surface.

It is such a can of worms we open when we begin to get rid of the glassiness! (and it makes for sexy glass!)

Barbara

Posted: Fri Jul 04, 2003 1:49 pm
by Doug
I would use diamond hand pads, They'll come in grit sizes from 70 to 3500. Sometimes I use the pads up to 220 then sandblast the scratches out with a 220 SiCa. Low temp firepolish at 1200F for 5 minutes. Nothing moves and the finish is...... Beautiful!

Posted: Fri Jul 04, 2003 2:50 pm
by S. Klein
Jackie: Of course I'm here. I thought for fireworks tonight that I'd crash cool two kilns at once. Oooooooooo, Aahhhhhhhhhh.

Here is what I do when I want that finish that you have to touch. I sandblast with 220 alum oxide with about 35 to 40 lbs pressure. Than I take my Makita hand vibrating sander with a 400 grit, 3 X 3 - 3M handpad under it, spritz lots of water on the piece and sand it. This will not leave any marks. Than I clean the piece really good. Than put a sponge and 600 grit wet sandpaper under the sander, sprinkle 600 grit silicon carbide on the piece, spritz and go. I do this for 20 to 30 minutes than get rid of the Makita and hand finish with the backside of the sandpaper and 600 grit silicon carbide. The finish will be irresitable and you wont even need to spray a finish on it. Only downside to this is that it totals your hands and your manicurist will hate you. Good Luck...........steve

Posted: Fri Jul 04, 2003 3:14 pm
by Ross
Steve... do you do this immediately after a full fuse? I would assume you would slump after the entire process?

Posted: Fri Jul 04, 2003 4:49 pm
by S. Klein
Depends on the shape. Sometimes this is done after slumping if the surface is fairly flat or slightly dished. If I slump after coldworking it is at very low temps..........steve

Re: Surface questions

Posted: Fri Jul 04, 2003 5:37 pm
by Brian and Jenny Blanthorn
Jackie Beckman wrote:OK, I need some help. This is one of those times when an experiment of my own would be the best, but running short on time, so if someone else knows . . .

During the second firing of my recent work I fire face down (on thinfire) - I like the crisp edges and the entire look face-down gives me much better for my current pieces. If the pieces will fit on my clay shelves, I prefer those, as they are flatter than my fiber shelves. If they are larger than a 20" square, I use fiber shelves. Up until now, after this firing I sandblast the entire surface, and sometimes carve it, then either firepolish or oil depending on the look I'm after.

A couple days ago I started playing with grinding? sanding? polishing? disks. I have been doing the entire surface starting at 50 grit and going up to either 800 or 1500. I really love the smoooooth surface I've been getting. But . . . the look I want is matte, and smooth and naturally - swirl free. Not so easy.

When I get up to 1500 I have the smoothness and the matte finish I like, but there are still swirl marks. I tried to oil at that point, and it does take away the swirl marks, but it makes it too shiney, AND there isn't enough tooth to allow the oil to sink in the way it does on a blasted surface. So - no good.

Then I sandblasted the 1500 surface lightly. This gave me a much smoother look than when I just sandblast a piece right out of the kiln, yet its not that "touch-me" smoothness I was really after. It does however allow the oil to sink in nicely and it has a nice matte finish, so better than the previous method.

Next, I tried to go up to 800 and fire polish very low - (1175) and I'm still waiting to see how that comes out.

So - question one: What to try next? Remember, I'm looking for smooooooth, matte, and swirl free. Anyone? (Steve Klein, if you're out there - help?)

Question two: When I fire the pieces face down on the fiber shelf rather than mullite, even though I use thin fire, the time I spend with the 50 grit is amazingly longer. I mean - FOREVER! This is because of the surface of the fiber board. Lots more of the little low spots that I never noticed when I was just blasting them. So - I thought what I may need to do is after the piece has been fired face down, giving me the look I like, perhaps I need to flip it over and fire it face up, THEN start with the disks. That would probably even the surface out enough that I wouldn't have to spend so much time with the 50 grit. But, would it change the look I acheived by firing face down in the first place? That's the part I can't forsee. I really like the look of the pieces when they are fired face down, and if I must spend forever with 50 grit, so be it. But - if I can flip and fire to even out the surface without loosing the look of the face-down firing, then that would be the ticket. Anyone know?

No-time-for-BBQs-and-fireworks-Girl
Ok just going 2 bed

But heres a few thoughts

Get a resonabble finish, lightly sandblast with fine grit I use 280 Silicon Carbide

Then rub with pumace

Get fine finish then rub with loose fine grit with peice of thich glass

Then rub with pumace

U could use a battery drill + brush

Even try brush with fine grit

Or do the sand blast or fine grit then light fire polish

An update and thanks

Posted: Sat Jul 05, 2003 11:54 pm
by Jackie Beckman
Just wanted to thank those who responded here or phoned to help . . . you're all just so nice.

Also - an update . . .

On a lesser piece I went up to an 800 grit disk then did a low fire polish. Not a great result, really - can naturally still see the few low spots that I couldn't get out with the disks. I spent several hours with the 50 grit, but the slight orange-peel looking texture of the surface just wouldn't go away in a few small low spots. This doesn't happen firing face down on mullite with thinfire, only fiberboard with thinfire. In order to get the finish I want, I'll probably have to flip and re-fire face up in a subsequent firing when I use fiberboard shelves. (Thanks Barbara for your input on that. I'll try it on something soon to see how it works for me, and report back.)

Although he doesn't fire face down on fiberboard, Phil Hoppes said when he polishes the bottoms of his pieces that were fired on fiberboard he can't get all the low spots either. So if Phil can't do it - I don't feel so bad. He's a wiz with those disks!

Being July 4th weekend, every place to buy loose abrasive and hand pads was closed today, but on Monday I'll be getting both to have on hand for the next important piece I'm working on. It's getting too close for comfort to play around anymore with the piece in question. What I ended up doing with it was taking it down the best I could with the diamond disks, then a light sandblast. Looks much smoother than sandblasting alone, so it will have to do for now. Brock had a great comment about this, saying that I'm the only one who is going to know what the desired finish was supposed to be, and as long as its done well, nobody else will ever notice. Thanks Brock - great point.

Steve, as for you, you are a gem for sharing your magical finish secrets. (Of course, now I'll feel too guilty to use them, but perhaps that was your plan. :wink:) Actually, I plan to incorporate some loose grit work and hand pads in some pieces I'll be working on next week. Thank you so much for the pointers. Your silky, creamy finishes are delicious. One thing I don't understand - can you explain to me what holds together the wet sandpaper and the sponge under your vibrating sander as you move it about the piece? And what do you think the results would be if I brought the piece up to 400 with my diamond disks, then polished by hand with the loose 600 SiCa and 600 grit wet sandpaper?

Brian - thank you for staying awake a few extra moments to help out. (You people sure go to bed at an odd time of day!) I have no experience with Pumice - HIS has two different sorts listed on their site - what kind do you suggest, and whats the difference?

Doug - Handpads would help "huge-ly." Thank you. I'll be looking into it after this endless weekend.

And Rodney - you probably have a point about the fiberboard - I am in a time crunch for this piece and therefore fired in on "naked" fiberboard covered with thinfire. Now though its been rigidized and I'll sand and kilnwash it before the next project to see if that helps with the low spots.

Thanks again everyone -
Jackie

Posted: Sun Jul 06, 2003 9:09 am
by Tony Smith
Jackie,

You probably already know this, but Abrasive Technology sells their handpads throught their company called Crystalite. They have both plated and resin handpads (the plated being more aggressive, durable and costly). They have the entire range abrasive size: 70, 120, 220, 400, 600, 1800 and 3500 with the finer grits only available in resin bonded pads.. http://ecprod.abrasive-tech.com/product ... dSubCat=83

Tony

Posted: Sun Jul 06, 2003 9:44 am
by Ann Demko
Tony, I checked out the handpad site and the page couldn't be found. Is ther another address. Ann D

Posted: Sun Jul 06, 2003 9:47 am
by Jackie Beckman
Ann Demko wrote:Tony, I checked out the handpad site and the page couldn't be found. Is ther another address. Ann D
It worked for me Ann, twice. Try again. And thanks for the info Tony.

J

Posted: Sun Jul 06, 2003 10:34 am
by Ann Demko
Thanks Jackie. It worked.

Posted: Sun Jul 06, 2003 12:50 pm
by Jane Lindell
Jackie:

Just to muddy the waters with another choice - I got what Abrasive Technology calls "diamond strips". They have the same surface as the foam handpads but can be used by themselves for inside curves and tight spaces or velcroed to a backing block for flat areas.

Here's the link:

http://ecprod.abrasive-tech.com/product ... dSubCat=33

Jane

Posted: Sun Jul 06, 2003 9:44 pm
by S. Klein
re the diamond pads. My .02. I have used them extensively for several years and fing that the 3M are superior in quality to any others on the market and definitely last longer.............steve

Posted: Sun Jul 06, 2003 9:47 pm
by Tony Smith
Steve,

I've only seen the 3M pads in 3 or 4 grits... are there more available?

Tony

Posted: Sun Jul 06, 2003 9:50 pm
by S. Klein
I use 60, 120, 220, 400, 600, 800. The 800 is resin bonded. I fing that over 600 begins to shine again............steve

Posted: Mon Jul 07, 2003 1:26 pm
by charlie
rodney wrote:ON THE UNEVEN FIBER SHELF
what you can do here is take the fiber shelf, all the time wearing a proper dust mask, etc,,,,,and get the belt sander, with a fine grit paper and smooth it out, once this is done, soak it with the RIGIDIZER, once it dries, go back, with a fine grit paper and sand it again,,,you may wish to put somemore rigidizer on it, but one time will probably work, hope this works

rodney
this won't work. it's EXTREMELY hard to to get a smooth and flat surface with a belt sander on a wide piece. you won't get swirls, but you'll get divots instead.

Re: Surface questions

Posted: Thu Jul 12, 2012 7:23 pm
by ecobbman
To make the board flat, take a big piece of flat glass, put a big sheet of sand paper on it and apply elbow grease. I do that after kiln washing a shelf with a 1000 grit sandpaper from the automobile finishing section of the auto store.