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Flat Lap Technique

Posted: Fri Sep 14, 2012 3:29 am
by S.TImmerman
I have several disks 6-18 inches and a 24" lap . I would like to start using the succession of grinding disks to make these smooth and attach a 1"x7" inch dowel with waterproof duct tape to the back. I have checked locally and no one provides coldworking classes and because of commitments I cannot take off to Houston or where ever to take proper classes at this time. Could someone please share the best way to grind glass disks on a flat lap please?

Thank you Much!
Shereen

Re: Flat Lap Technique

Posted: Fri Sep 14, 2012 4:06 am
by Morganica
What happened with the dowel method?

Re: Flat Lap Technique

Posted: Fri Sep 14, 2012 4:40 am
by S.TImmerman
Morganica wrote:What happened with the dowel method?
Ah, someone else is a night owl eh ;). I think it was your post that suggested using a dowel and waterproof tape. I'm actually a bit scared of not doing it right and have a jagged rod disk catipolted towards me (or my golden who always lays so he touches me while I work) So I wanted to know the right way befor I tried it. Is there a way you can explain it?


I so wish someone in southern calif taught coldworking as I just got my wet belt sander too. Bullseye has a short video on it which I'm thankful for!

Re: Flat Lap Technique

Posted: Fri Sep 14, 2012 11:02 am
by David Jenkins
Some questions/comments:

1. Your disks are 6-8" in diameter, and the lap has a 24" diameter wheel? If that's correct, I would think you'd have to be really, really careful of not letting your piece extend over the edge of the disk, or you'll risk getting grooves in the piece where it laps over. But I may be misinterpreting your post.
2. Are you polishing a glass disk? I have found that to be a difficult exercise - esp. in achieving a single-plane surface. Just the slightest variation in pressure on the dowel you're using will cause (or at least it has for me) a "faceting" of the surface you're trying to grind. YMMV, though.
3. I've followed instructions I've found elsewhere here (they may have been lost when the archives disappeared) as far using a broom handle piece as a handle. I make a piece that extends past the edges of the glass 3"-4" and just tape the bejabbers out of it using the good waterproof duct tape I got from HIS Glassworks. Works like a champ.
4. Do your disks have a hole in the center (for laps that feed water through a center hole)? I got one of those by accident, and even though it's essentially a flat disk, I've had problems with that center hole leaving marks on the glass if I move the piece back and forth over the hole. I'm guessing it's operator error, but until I perfect my technique, I avoid using that disk.

HTH

Re: Flat Lap Technique

Posted: Fri Sep 14, 2012 4:48 pm
by Laurie Spray
We use lg suction cups to hold the glass on our 24" flat lap..... Not sure what you are trying to do...

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 12:18 am
by S.TImmerman
I have rod disks that have hundreds of cut rods and disks that are round pot melts that range from 6-13". I remeasured the disks today. They are not very smooth and I want to perfect them before I slump them Into bowls. The flat lap grinder has 24 flat disks in several grades.

Laura, where do you buy the suction cups? May I have the link to ones you bought?

Yes,the disks have a hole but the water system comes up the side and I can position it wherever I want. This is the same lap that his glassworks sell but I bought it from grindglass.com

Thank you for any help
Shereen

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 9:18 am
by David Jenkins
Sorry - I misinterpreted the disk measurement you cited - I thought you meant the abrasive disk was 6" in diameter, and you were talking about the glass disk. Right?

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 10:30 am
by Kevin Midgley
Suction cups can be great but........ it is possible to leave suction cup ring marks on the glass that show up on the finished piece. :o

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 10:30 am
by Marty
CRL has the suction cups.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 11:35 am
by Laurie Spray
Something like these
http://sell.lulusoso.com/selling-leads/ ... e-etc.html

I have never had them leave a mark on the glass.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 4:23 pm
by Kevin Midgley
I guess Laurie that you haven't fired enough clear glass so as to experience the marking potential of suckers.
You've been lucky in other words.
The marks are 'invisible' until the glass is fired and pretty much cannot be removed once on the glass.
At least I've never figured out a surefire removal method other than not using suckers in the first place.
They can be seen by blowing warm breath onto cold glass.
In the old archives there was much discussion about this.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 4:56 pm
by Brock
Yup, been there, done that. Good cleaning required before firing.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 5:24 pm
by Laurie Spray
I have seen
that..... All i do is take very fine steel wool and glass cleaner using some elbow grease and i do not have that problem. Lucky? I'll take it!

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 6:27 pm
by Morganica
I've used the suction cups and had them slip off during lapping, so be careful. If the glass isn't fused totally flat and your attention wavers a bit, you can jostle the cup enough to let in some air, destroying the vacuum and creating a lovely shrapnel effect as the glass flies across the room.

The piece needs to be clean for duct tape (and it's usually pretty clean straight out of the kiln, since oils and things have burned off). And you need a lot of duct tape, applied in multiple directions.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 8:11 pm
by S.TImmerman
David Jenkins wrote:Sorry - I misinterpreted the disk measurement you cited - I thought you meant the abrasive disk was 6" in diameter, and you were talking about the glass disk. Right?

David, absolutely no problem!! I'm so greatful for all the experience of artists here . Perhaps it was me that didn't use the correct lingo. 8" Glass disks. =: about 1000 1/4 inch rods stacked up and fused into a "glass disks". (what is the proper lingo?)

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 8:18 pm
by S.TImmerman
[quote="Laurie Spray"]Something like these
http://sell.lulusoso.com/selling-leads/ ... e-etc.html

I have never had them leave a mark on the glass.[/quote

Thank you Laura , btw I love all the items I've bought from you!

Morginia , thank you for the caution, I think ill get one that shows when it's losing suction so I can use the emergency break on the flat lap

I'll really clean them well with steel wool too

John at grindglass.com is the one that makes the flat laps for hisglassworks and is very nice to work with.

Re: Flat Lap Technique

Posted: Sat Sep 15, 2012 8:27 pm
by Brock
. . . (what is the proper lingo?)

Blank.

Re: Flat Lap Technique

Posted: Sun Sep 16, 2012 2:45 am
by Laurie Spray
I do not use duct tape..... And i do use a sucktion cup that shows if it even starts to lose suction. I would not try to use one unless the bottom is totally flat.......i should have said that!

Re: Flat Lap Technique

Posted: Sun Sep 16, 2012 2:18 pm
by Valerie Adams
S.TImmerman wrote: 8" Glass disks. =: about 1000 1/4 inch rods stacked up and fused into a "glass disks". (what is the proper lingo?)
This is the technique that Els Vanden Ende was working on at Pilchuck in 2010; she did some really beautiful work that's now traveling in Bullseye's Act 2 The Glass Track show.
http://www.bullseyeglass.com/kilnformin ... a-377.html

Re: Flat Lap Technique

Posted: Tue Sep 18, 2012 1:25 am
by S.TImmerman
This is the technique that Els Vanden Ende was working on at Pilchuck in 2010; she did some really beautiful work that's now traveling in Bullseye's Act 2 The Glass Track show.
http://www.bullseyeglass.com/kilnformin ... a-377.html[/quote]

Very nice work, thanks for sharing it, her name suggests she's Dutch, German maybe.. I'm Dutch

I want to eventually do designs with different colored rods. My New Paragon Caladra kiln quit after the 16th firing and I bought it for Vitrograph to pull canes - i had not set up yet and this happened. it is less than 3 months old :( that gold colored wire is supposed to be attached to that white ceramic piece.