# Colabrative help on silver clip



## bitshird (Jul 6, 2008)

Here is a rendering of a clip that I think I'll try, I believe it will have enough tinsel strength to keep from bending the way the outer edged are filleted and the center is crowned I think there will be about a 4% to 7% shrinkage rate, I wonder what opinions are on the ball on the tip,  could it just be on the bottom and allow the natural edges to continue on the top surface since it goes to a taper any way, and just keep the ball or half hemisphere on the bottom , or bust a plain half round,
 I'm not fishing for a market, I'm not advertising, nor doing market research or testing the waters, just looking for suggestions since this part has proven to be the biggest buggaboo on making kitless pens.
Jeff if you feel this post is in error please remove it.
I'll set up a piece of wax and get it in the mill, after I get some suggestions,


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## Texatdurango (Jul 6, 2008)

I think the bevel look is nice.  I think leaving the ball full at the bottom and possibly rounding over the top similar to the #4 clip below would look nice.

You mentioned shrinkage, are you planning on casting with sterling or using PMC?  I didn't think sterling shrank when cast.

By the way, if this kind of thread doesn't belong here, nothing does!


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## bitshird (Jul 6, 2008)

George, unfortunatly there is always shrinkage, I'll loose 1% on the RTV Silicon mold and another  2-3% on the wax model and possibly another 2 or 3 when I cast the metal, it all goes back to the principal of thermal expansion, and contracting when the waqx and or metal cool.
 I'm just going to cast this on using regular sterling grain, I have some Argentum at my disposal, but don't want to use another crucible,and I'm not sure of the ductile strength, I've used it and it is nice in that it doesn't oxidize and tarnish, but my thoughts are if you want sterling, then learn to polish it  I've been writting the code for it since I posted, should have the wax master in a few hours. 
CNC is wonderful[}][}][}][}][}][}][}][}]


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## BRobbins629 (Jul 6, 2008)

This is a case where one test is worth a thousand opinions, but in my opinion, if I'm reading the dimensions correctly, the .127 height is a little too thick.  I'm fabricating clips from 14 gauge (.064) sheet or even half round that is about .060 to 0.080 high and that gives plenty of strength.  As for the ball, you will only know which you like when you make both.


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## bitshird (Jul 6, 2008)

Bruce, you're reading it right, at the bottom of the grooves though I believe it's only around .07 -.08 , it's also tapering as it goes towards the tip., there it's only .04 just as it goes into the ball end.
 I've thought about soldering some patterned wire to some 20 ga. sheet for a clip, and making a band from the same wire, even using gallery bezel over sheet to get the thickness then cutting a tenon for the center band in the cap for a different look, something like some of the Gisi pens[)]


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## ldb2000 (Jul 6, 2008)

Hi Ken
I'm casting a similar clip with almost the same dimensions as yours but I don't have the equipment to do it in silver so mine is cast in pewter (not as nice as silver but it works ) .
The size is a bit clunky but it has plenty of strength and holds up well .
I use 1/32" tinned brass strips for mounting into a slot in the finial and cast it into the clip for added strength (the pewter bonds great to the tinned brass) the brass has enough flex at the mounting point that the clip flexes without bending (not as much as I would like but very workable)








PS: If Jeff removes your post I say we TAR and FEATHER him [)][)][)] 
We finally have an advanced penturning post


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## ESwindell (Jul 7, 2008)

Ken,
I have not made any clips before, that said I know that the commercial clips have the backs hollowed out I am not sure if that is to save material or if that give the clip some sort of structural strength or both.  I would also guess that you would need a two part mold to cast it.  I was also wondering how you are planning to attach this to the pen as there is nothing in your pattern ring/post that I can see that would allow this, or is that a separate cast and then you attach the two after.
God Bless,
Eric


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## bitshird (Jul 7, 2008)

Eric I can fabricate a ring, from sterling sheet,cut a slot for a piece of 22 or 20 ga.
 I have a set of disk cutters the go from 1/16th to 1 in, all I have to do is punch out the size hole I need for the match up for the cap size then punch another hole for the finial to press through, this way, I only have to have one or two clips and can adapt them as needed fro a slimline to a Gent or El Grande, I cut the first one yesterday and will be doing another today, I've thought about removing stock from the back, it seems like the side wall should add some structural integrity, we'll see down the road.


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## Daniel (Jul 7, 2008)

I was thinking that the 0.127 side could be tapered in towards the bottom. Maybe half way down that side. Wish I could do a drawing of my own, this would give the appearance of a thinner clip while still keeping the meat. I agree with doing something with the top end. nothing to fancy but Don't have any specific suggestions just yet. As for the ball. not completely spherical but not cut all the way down to the clip profile either. just flatten the ball a touch on the top surface. otherwise I can't decide between the two extreme choices.


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## bitshird (Jul 7, 2008)

Daniel, it does taper towards the bottom end, also the .127 is at the top of the ridges and crown, just before the ball at the end the clip is only .065, keeping in mind the ridges run all the way to the ball, I haven't weighed the wax yet, but I don't think it will be that bad, once I have it cast I can mill out the back if necessary,I didn't like the fully spherical ball so I flattened the bottom a bit.


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## hebertjo (Jul 7, 2008)

What about a clip that is pinned or bolted to the pen. Much like the Gisi's do on many of there pens. Here is an example:

http://www.penmakersguild.com/gallery.php?gallery=gisib&page=16


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## Texatdurango (Jul 7, 2008)

> _Originally posted by hebertjo_
> 
> What about a clip that is pinned or bolted to the pen. Much like the Gisi's do on many of there pens. Here is an example:
> 
> http://www.penmakersguild.com/gallery.php?gallery=gisib&page=16


Are you sure those are pinned or bolted to the body?  I've never seen one of these up close but have often thought those rivets were just decorations for looks, that the clip was attached similar to having a center pen inside the pen body.


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## hebertjo (Jul 7, 2008)

You could be correct, I have never seen one up close either but I have looked a variety of their pens and they use the same bolts on all of them even when the brass bolt clashes with the rest of the pen color theme. This is what leads me to believe they bolt them on. You can find those brass bolts where model railroad stuff is sold and you can buy taps for the very tiny threads from Micro-Mark. A little red locktite or epoxy and you are all set.


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## hebertjo (Jul 7, 2008)

Forgot one other thing, their pens tend to be thicker then most kits so that gives you more material to turn threads in which would give the bolts more holding power. Anyway, I think it solves some design issues but opens up others. I think you have me inspired to order the tap set and attempt to bolt some aluminum to a turned tube. I'll report back once I have tried it.


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## bitshird (Jul 7, 2008)

Hebertjo, I'm not much of a betting man, but at best those are pins, sort of like rivets, a few places they use them they would be too short to be of any value in holding, Technically a bolt or threaded screw only needs to be threaded into the joined parts a distance of half the diameter in order to attain full holding power, about the smallest commercially available machine screw I know of is  0-80 the body diameter of this little sucker is only .060, I know of a fellow that made an operating miniature steam engine that he had to make the hex head screws for the boiler ends, they were if memory serves .015 with 100 tpi, pins like that could be cast but man what a job cleaning them up, I'm getting a 4th axis in a few weeks, I may try something like that,


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## Paul Downes (Jul 10, 2008)

Just a thought. I haven't made any jewelry for a long time, but....Could you have a strip of stainless underneath the silver decorative part of the clip and silver solder the stainless to the silver? Couldn't you also cover the stainless with silver solder?


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## bitshird (Jul 10, 2008)

Paul, Sterling can be silver brazed/soldered to stainless, at least most Stainless some alloys have too much Chromium in them to solder to.


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