Silver splitting when coring

tammydownunder · #1 2010-08-19, 5:57pm

I have cored many a bead with terrific success on my Impressa. But, I've made a new style of pendant and twice now, I've split the silver. I am cranking only 1/2 turn to start with and by the 3rd or 4th go, with plenty of room for the bead to spin, the silver splits.

I'd love to know what I'm doing wrong and why don't I have this problem with my normal BHB that fits with Pandora etc...

NLC Beads · #2 2010-08-19, 5:59pm

Too much silver? Mine did that when I cut too long and it didn't have anywhere else to go.

squid · #3 2010-08-19, 6:09pm

New tube of silver? There was a problem with one batch from IFS - the tubing wasn't made seamless. Does it appear to have a seam?

tammydownunder · #4 2010-08-19, 6:14pm

I'm using the same formula that I normally use which is I measure the bead and add 3.2mm for coring. Plus, this happens within the first couple of turns.

tammydownunder · #5 2010-08-19, 6:17pm

I've been getting it from my local supplier and I think they get it from Indian Jewelry Supply

Jenn L'Rhe · #6 2010-08-19, 6:25pm

I usually do a 3/4 turn on each end the first time then go to 1/2. Are you centering the bead on the tubing as you turn?

Gillianbeads · #7 2010-08-19, 6:27pm

I anneal mine first...perhaps this tubing is half-hard or hard?

tammydownunder · #8 2010-08-19, 6:46pm

I've been coring beads with the same piece of tubing without a problem. The only thing I can come up with is the pattern is a pit raised. Would that effect it? Around the hole, everything seems pretty level.

lenora · #9 2010-08-19, 6:47pm

Quote:

Originally Posted by tammydownunder

I've been getting it from my local supplier and I think they get it from Indian Jewelry Supply

Is it a brand new tube of silver, even if it's from a larger order? It could just be one bad section of tubing or an entire order of bad tubing. I would try it with a new piece of tubing and start from there.

melzip · #10 2010-08-19, 7:09pm

I find that the silver will split if the tube is cut too long. I always make my tubing .088 larger than the actual measurement of the bead. So, take your bead measurement and add .088 to it and this will be your total tubing to cut. If you're ever larger on one side of the bead than the other, try to stay within 1/1000th of the smallest measurement. Since i've followed those measurements I have no splitting problems. I hope that's not too confusing.

tammydownunder · #11 2010-08-19, 7:16pm

Quote:

Originally Posted by melzip

I find that the silver will split if the tube is cut too long. I always make my tubing .088 larger than the actual measurement of the bead. So, take your bead measurement and add .088 to it and this will be your total tubing to cut. If you're ever larger on one side of the bead than the other, try to stay within 1/1000th of the smallest measurement. Since i've followed those measurements I have no splitting problems. I hope that's not too confusing.

Thanks. Can I assume you are talking imperial measurements? .088 = 2.235 mm.

philomena · #12 2010-08-20, 7:17am

Hello Tammy,
try this: Heat the Silvertubing to a light orange glow and put it into cold water immedeatly.
This makes the silver of your tubes soft.
Silver (and other metals too) will get brittle when morphed. When make silver tubes by hand after a few forming steps you always have to heat the Silver up to the orange glow and cool it to make it flexible again.
But don't heat to much. This destroyes the metal structur completly.

The only extra thing you need to do (after heating and cooling) is to put the tubing it something like thined down sulfuric acid or diluted alum to get it shiny again.

Or if you have a goldsmith near by ask him/her to do it for you.

Best regards
Kathrin

GinnyHampton · #13 2010-08-20, 9:25am

How are you cutting your tubing? If you're using some sort of mini power saw, it can leave a tiny ding on the edge of the tube and if you don't file the end down past where the little divot is, it'll split right there. I'm wondering if it has to do with how you cut it. But if you use a jeweler's saw and do it by hand, then I'm probably completely wrong

It looks like it's splitting right away so it has to be the tubing and not anything to do with the decoration on your bead. There's either a seam inside that bead, or something is happening with your cutting. Lenora's idea is a good one, try another piece of tubing and see if the same thing happens.

I've cored literally hundreds of beads and anytime my tubing split that soon it was either because I got a bad (seamed) piece or my saw left a little nick at the top that I didn't take care of.

Totally cute bead, BTW!!!!!

tammydownunder · #14 2010-08-20, 2:53pm

I bought a fancy small pipe cutter made in Germany which is supposed to be the best brand out there as opposed to the inexpensive one at the local hardware store. I deburred the inside and I was pretty sure that I didn't find anything rough on it before I cored it. But, both times, the silver split. I'm going to try again with a shorter piece of tubing and I will make certain that there are no jagged edges.

tammydownunder · #15 2010-08-20, 8:51pm

I made sure that there were no burrs. I cut the tubing shorter and I really took my time flaring each end. YEAH!!! It worked! Thanks for all your suggestions. I was so happy with the bead and it needed the silver core to finish it off.

squid · #16 2010-08-21, 9:31am

That is very cool - glad it worked!

ginko · #17 2010-08-21, 10:16am

Wonderful! Pretty bead. I love the side core look.

GinnyHampton · #18 2010-08-21, 11:56am

Great job!
It may have been that you were just flaring too much at one time. I cut my tubing a little longer sometimes when I want a nice rolled/raised lip - but - I do tons of small 1/4 turns with the impress so that it doesn't split.
If you feel like experimenting, maybe try a longer piece again, but do tons of small 1/4 turns each time and see what happens.

Tabitha · #19 2010-08-22, 12:51am

I use the Impress and Ginko's tubing and had this problem for a while- worked out I was not deburring it evenly, least I think that's what it was, because after I was a bit more careful with the deburring (with the tool) I haven't had the problem for ages (touch wood)
I cut 4.02-4.05mm longer and start with just under half a turn and then go to 1/4 turns.

ginko · #20 2010-08-22, 8:48am

I do this weird chant of "stretch" in my head when I am coring. Okay, may not that scary, but keep in mind you are stretching a thin, soft metal. Ginny is right, 1/4 turns will gently stretch and help prevent splitting. Flare 1/4 turn, flip, flare 1/4, fip, and repeat as needed. My cuts are 2.5 to 3mm longer than the width of the bead. I think 4mm is asking a lot of the metal, and may be too much to stretch with accuracy. I certainly would flare in small increments if I wanted that much of a edge.