Making a ring mandrel- jewellery tooling

I won't raise to the bait...

Clearly a seasoned forumite !!!!

I made a ring mandrel for two engagement rings. Got the dimensions from the proposer, who is an engineer and who knew how to measure rings.

The mandrel consisted of 3 turned diameters; one for "hers", one for "his" and one to fit into a drill chuck. Rings made of wood - turned out beautifully, and they "worked" as the wedding was about a month ago.

Is a brilliant idea. Why bother making something you're never likely use again when you probably already have something in the workshop.

My sausage fingers are probably more like MT3. Was about to say i know a few people who'd be MT4 but it is probably mythical ogre sizes fingers.

Michael W

Not only lots more information, but a good laugh as well!

Gary, I want to make the ring out of a silver coin. I want to make it so that the year of the coin (her birth year, of course) is visible. I may have to use an American silver quarter, as they apparently were made with a high silver content until 1964, unlike British coins which, again apparently, stopped having a high silver content in 1920.

I initially considered buying some silver strip from Cooksons in Birmingham and piercing it to make a kind of filigree effect, but then I saw this video on YouTube-

https://www.youtube.com/watch?v=7Q8aokoIH9Y

-where a coin is used.

I will practice on some copper tubing before trying to make the silver ring.

I apologise for my rather haphazard approach to this, I have a, ahem! pragmatic learning style which leads me to want to 'have a go' rather than approach a new technique circumspectly.

Thanks again for all the help and knowledge!

Regards,

John.

You will find that copper tubing as used for house supply, plumbing etc will be too thin to do much with. Copper is OK - a bit chewy to cut but OK to hammer, polish, etc, it is the thickness that will let you down. You could try making a ring from a two-pence piece, but try with a magnet as the latest versions are not bronze... If you get the bronze version, remember to anneal frequently as working it will be harder than copper or silver.

Anyone seeking a different approach is invited to consider casting into a home-made mould. Cuttle-fish bone is good for this, easy to find from the pet shop (ask for the big bits) and excellent to cut. The cast material can be silver (or gold, once you are confident) - other materials are available but are either too hard to melt or leave green rings on the finger.

Brass casting could be done in cuttle-fish, for model parts - so if there is an interest we might add this to Neil's list of new topics.

Cheers, Tim

OldMetaller, would you like me to see if I can find the jig I made coin rings with ? It was 40 plus years ago but I think I have seen it in the workshop somewhere. It works so you can read the year etc on the inside.

I look forward to receiving your manuscript Tim

Neil

Don't know much about it til your comment, Tim, but it definitely has this amazing natural grain effect as evidenced here;

Would be cracking material to machine on my CNC sherline mill, create some funky shapes on mach 3, put a carbide burr in the collet and bobs your uncle so they say (in my case he really is).

Michael W

Edited By Michael Walters on 20/09/2016 22:15:39

Tim, thanks for some great ideas, I will definitely try it on a few 2p pieces first- even a tightwad like me can't moan about such economical raw material! Thanks for the heads-up about copper pipe being too thin, I would have found out the hard way!

Chris, that's really kind of you. What I would really like, if you manage to find your ring-making jig, is a photo or sketch so I could try making my own jig. I always think that making a jig for a job like this is a great idea, but I usually fall down on the actual execution of it due to my lack of experience.

You chaps are the absolute tops!

Regards,

John.

"We wants it, we needs it. Must have the precious!"

Hi John,

To make a ring that way you will need a ring triblet. One that I use tapers from 25mm to 8.5mm over a length of 310mm. The half angle of the taper is calculated as...

arctan(25-8.5)/(2*310)) = arctan(8.25/310) = arctan(0.027) = 1.55degrees

When I started making jewellery I made my own triblets; but instead of making a smooth taper I made them with a number of short steps with each step corresponding to a specific ring size.

Thanks Gary, that's something else to think about. I've just had another look at triblets on Cookson's website and frightened myself at the prices... I think I'll be doing some taper turning over the weekend! Thanks for the detail about the required taper, I also note your earlier point about there not being any 'set' taper and that triblets can vary.

If I get anything worth reporting, I'll post on this thread.

Don't hold your breath!

Regards,

John.

OldMetaller, I have found my little jig. PM me and address and I will put it in a jiffy bag and post to you. Chris.

An old thread but still here. I am just starting making various rings from old coins & the like. One of my 1st jobs with the new lathe is to make a stepped mandrel to hold the rings in the lathe. Luckily there are a few youtube vids showing how to make them. Steve Jordan makes all sorts of things & I usually watch him on an evening when all's quiet. Just to say the ones I have seen made are made from alloy.

Edited By Steviegtr on 02/01/2020 19:40:44

I asked at a jewellers about making my gold wedding band a bit bigger (my finger is fatter than it was 40 odd years ago). I got a very negative response, the guy said he would have to send it off for an estimate. I decided he could do without my business and did the job myself with a no.3 morse taper and parallel no.3 morse taper socket (as used in turret lathes). Gently tapping the taper into the ring whilst supporting it against the socket, turning it over and checking the size often. This did the job without marking the ring and I finished up by holding the ring on the taper in the lathe and polishing it.

I have a couple of expanders see pics. The top one I hope to turn down to put steps to hold rings in the lathe. Was very cheap on ebay. The bottom one was expensive but very good & even has dies at the bottom for shaping. Gold is very soft & they say easy to enlarge a half or full size as long as they have never been split repaired or resized using welding/gold brazing. Being prone to snapping at that point.

stevie, I too have a ring reducer/expander of the lower type. The dies are where you do the reducing (by driving the ring into the hole that is the minimum increment smaller than the ring's current diameter). It only really works with D profile ring shanks, not flat profile, which would get excessively marred.

It's always best to anneal a plain band before sizing up or down if you're going to resize by moving the metal using main force rather than by cutting and resoldering. In most cases gently heating a plain band is a useful way of revealing whether it has been soldered anywhere - a solder line will become more obvious when heated.

daveb, relatively few high street jewellers these days fabricate rings (as opposed to having them cast or buying off-the-peg castings) and even fewer fabricate them on site. This means that even routine jobs like resizing increasingly have to be sent out. "Sent out" can mean somewhere like www.makermends.com or as far as Hong Kong.

Edited By Bill Phinn on 03/01/2020 01:18:48

As an engineering solution I would definitely turn a ring from titanium.

I've made quite a few over the years, both male and female styles.

Heating the titanium when finished gives a beautiful colour finish, but I also file work them for decoration.

It's far easier to make the ring to size on a lathe for me, unless you're going to precious metals and have very deep.pockets.

Mick