|
Post by opalpyrexia on Jun 9, 2018 14:22:08 GMT -5
Do you thrum? I do occasionally... ...with trepidation. If you're new to the term, thrumming is the use of strings or cords (with polishing compound) to polish areas that are difficult to reach with wheels or burs. While it works very well it can leave grooves in the metal if you're not careful. I was finishing a custom pendant for a customer that required thrumming. I made it in silver with two 14K bezels for a tourmaline and diamond. I like to finish the back of my pieces with a matte finish (to eliminate scratches from fabrication) using an abrasive wheel on my polishing machine. When I did that the fibers of the wheel managed to scratch the large bezel where I've indicated in the second photo. Crap! How am I going to get those out? I couldn't get a wheel in there. Thrumming the bezel by hand with cords risked leaving marks in the softer surrounding silver. Here's what I did. Do you sew or know someone who does? My wife sews. So I know what bias tape is. Bias tape to the rescue! Here's a rough sketch of what I did — Mounting the pendant in a block of thermoplastic, I clamped the block in a vise. Then I took a length of 1/4" bias tape with tripoli (and then rouge), ran it around the bezel and thrummed with a back-and-forth pulling action. It did the job quickly and to my great relief the silver was untouched. Problem solved. Customer happy.
|
|
|
Post by Pat on Jun 9, 2018 14:48:17 GMT -5
Yes, I’m a thrummer. Always use cotton string. Good idea to use bias tape.
Your piece is beautiful!! Thanks!
|
|
|
Post by opalpyrexia on Jun 9, 2018 16:08:42 GMT -5
Thanks, Pat . I'm always tense when using strings. Oh, no, another pun. Sorry.
|
|
|
Post by rockjunquie on Jun 9, 2018 16:22:22 GMT -5
Beautiful piece and clever save.
|
|
|
Post by fernwood on Jun 9, 2018 17:00:26 GMT -5
I use bias tape or strips of soft leather when needed.
|
|
|
Post by toiv0 on Jun 9, 2018 17:34:00 GMT -5
Cool Idea if I can remember it when I need it. Great piece, I am in awe!
|
|
|
Post by opalpyrexia on Jun 9, 2018 20:04:14 GMT -5
I use bias tape or strips of soft leather when needed. Thanks, I figured I wasn't the only one, although I haven't tried leather. I'll have to try it. We have some that we picked up at the old Amity leather outlet store in West Bend years ago. I actually prefer the bias tape over string except for really tight spots. The tape conforms to the shape of the metal without cutting deep, provided that I keep an eye on the edges of the tape. That should be true for leather, too?
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,732
|
Post by gemfeller on Jun 9, 2018 22:18:42 GMT -5
Beautiful piece and very cleverly designed. In tight spots like that I usually use Shofu Bownie/Greenie/Supergreenie points. They're small enough to reach into many small places and a little less hassle that thrumming when they'll fit IMO. Otto Frei used to carry them. www.shofu.com/en/products/abrasives/stones/browniegreeniesupergreenie-polishers/Rio Grande used to sell a string type thrumming abrasive in several shapes and grits. As for bias tape, never heard of it until this thread. Sounds like a good solution.
|
|
|
Post by Pat on Jun 9, 2018 23:58:31 GMT -5
Thanks, Pat . I'm always tense when using strings. Oh, no, another pun. Sorry. I'm a punist/punerator/punoralatorist/punician. Don't apologize for puns around here
|
|
|
Post by opalpyrexia on Jun 10, 2018 9:23:23 GMT -5
In tight spots like that I usually use Shofu Bownie/Greenie/Supergreenie points. ... As for bias tape, never heard of it until this thread. Sounds like a good solution.
Thank you. I have a dental supply company less than a mile from me. Their website has Shofu Greenies and Supergreenies listed as a bulk purchase with no details. If they're small I can certainly see the benefit over regular polishers. I really do need to walk over there and say hello.
The silver arch/bail of the pendant had some marks and light scratches underneath from forming it. I considered thrumming with bias tape, but I elected to use a G-Tac Slurry Coated Polishing Strip in a jewelers saw frame. It worked extremely well in putting a moderate shine on the surface. In fact, I think the product is worthy of a separate post.
|
|
|
Post by Rockoonz on Jun 10, 2018 11:51:45 GMT -5
Thanks, Pat . I'm always tense when using strings. Oh, no, another pun. Sorry. I'm a punist/punerator/punoralatorist/punician. Don't apologize for puns around here so if I steal the puns of others does that make me a repunican?
|
|
|
Post by Rockoonz on Jun 10, 2018 12:27:12 GMT -5
In tight spots like that I usually use Shofu Bownie/Greenie/Supergreenie points. ... As for bias tape, never heard of it until this thread. Sounds like a good solution. Thank you. I have a dental supply company less than a mile from me. Their website has Shofu Greenies and Supergreenies listed as a bulk purchase with no details. If they're small I can certainly see the benefit over regular polishers. I really do need to walk over there and say hello.
The silver arch/bail of the pendant had some marks and light scratches underneath from forming it. I considered thrumming with bias tape, but I elected to use a G-Tac Slurry Coated Polishing Strip in a jewelers saw frame. It worked extremely well in putting a moderate shine on the surface. In fact, I think the product is worthy of a separate post.
Yes, please do.
|
|
gemfeller
Cave Dweller
Member since June 2011
Posts: 3,732
|
Post by gemfeller on Jun 10, 2018 15:29:06 GMT -5
In tight spots like that I usually use Shofu Bownie/Greenie/Supergreenie points. ... As for bias tape, never heard of it until this thread. Sounds like a good solution. Thank you. I have a dental supply company less than a mile from me. Their website has Shofu Greenies and Supergreenies listed as a bulk purchase with no details. If they're small I can certainly see the benefit over regular polishers. I really do need to walk over there and say hello.
The silver arch/bail of the pendant had some marks and light scratches underneath from forming it. I considered thrumming with bias tape, but I elected to use a G-Tac Slurry Coated Polishing Strip in a jewelers saw frame. It worked extremely well in putting a moderate shine on the surface. In fact, I think the product is worthy of a separate post.
I checked Otto Frei's selection and if you can get retail pricing from your dental supply company you might find a wider selection of shapes/sizes. Shofu offers several options not available at Frei: www.shofu.com/en/products/abrasives/stones/browniegreeniesupergreenie-polishers/
|
|