cnc mill for jewellers

[ajd171]

Hello everybody! I'm the newbie in cnczone.I intended to buy cnc machine for my wax model but I have no idea which one should I buy and well suited for me.help.....Thanks

[under-dog]

This is what I have found. I am not telling you for sure this is what to go with just that this is the route I went. Everyones expectations, needs and budgets are different. I dont want to be the one to tell you what to buy but I hope this helps.

I have been a jewelry designer and model maker for about fifteen years. Primarily by hand. I have used 3-d printers as well. From what I have found no matter what you use it will need hand finishing and detailing in the end. This is something to keep in mind when purchasing. Dont expect to pull a fully finished peice off any machine. Jewelry is far to fine and detailed for those expectations.

I have just recently purchased a system myself for my home shop. So I have just put the research in myself and am in the process of fine tuning, adding accessories, setting up and just learning in general to get the results I want.

Your budget will determine alot. In the reasonal budget range two sytems seem to be prevelent. Sherline and taig which are both well suited to working on the smaller part sizes and softer materials we use in jewelry. I went with the taig as it seemed a more rugged machine for the price. Also, although sherline offers the most comprehensive line of accessories, thier machines do not seem to work as well with other accessory mfgs as easy. Alot of the sherline accessories are easily usable on the taig(some modifications may be needed)

I do prototyping of larger fiurative and gift items as well so the slightly larger size of the taig is welcomed.


So far I have been happy. I have only made a few test pieces after getting everything setup corretly and running right. I am still in the phase of seeing what it can really do. I am waiting for my parts for my fourth axis to arrive and am in the process of learning how to get the machine do do what I want so I cant give you a full assesment on the limits to its capabilities. What I mean at this point is that my experience is the shortcoming and not the machine.

My expectations when I purchased it where that it would take a good portion of the grunt work away from me freeing my time to concentrate the detailing aspects. When I say grunt work I mean the cutting, roughing out, Layout type work. As anyone that has designed and made anything in CAD, certain types of geometry will be far better suited for designing in CAD and some just arent worth the time and it will be easier by hand. The key is knowing where to draw that line.

I bought my mill from Nick Carter at Carter tools. He was very informative, best prices. He uses his personal taig equipment for making jewelry as well. I also just purchased my fourth axis from him.
I bought the software and controller(with motors from another source)

I can tell you exactly what my setup is if you wish. As I said I am merely giving you a diary of the process I have and am going through myself.

I added a couple of links which I found useful in my search.




http://www.tabletopmachinewiki.com/w...Jewelry_Primer -good breakdown for the jewelry person trying to get thier feet wet in CNC

http://www.cuttingedgecnc.com/programs.htm -great source for the CNC newbie

[Joules]

Take a look at the Roland Modela MDX 15/20 machines. They have a good user base of jewellers, and come with a competant pack of software for use out the box. Very good for working wax and plastics, but not really upto metals.

http://www.rolanddga.com/asd/products/scanners/mdx15/
http://3dwaxmill.com/phpBB2/album_cat.php?cat_id=1

Also a new group on Yahoo for owners of these machines... Ahem!!! run by yours truely...sorry for the plug...

Joules

p.s
I use my MDX-20 on the kitchen table run from a laptop using Rhino for designing in.

[surfer93]

hi under-dog,

I am also interested in using a taig mill for jewelry prototyping. May I ask what cad/cam software do you use? In your opinion, can the taig carve out school rings?(will it be able to carve out the small letters/initials?) Thanks


Don

[under-dog]

As I said I have not had alot of time to work with it and really put it through the ropes. I am still very new to this and my limitations are the major factor at this point in finding the machines limitations. I am also waiting for my fourth axis. I have only produced what I would call one succesful test sample so far. It was just something to guage the level of detail. cutting times, etc. that I might expect. Just to note this was not just my first true attempt off this machine but off any cnc mill for me. Prior to this I was cutting quik sample "chips" to tune in the machine and get an idea of how it and cnc milling worked so this does not mean there were failures. It was just the first piece where I actually figured out how to get things working the way I expected. It is a one sided relief. I have not attemted to flip mill yet as I have some ideas for doing this with the 4th axis. It didnt come out too bad. I think some fine tuning on the machine and my CAD files will improve it.

The main point to seen here is that it took me about 2 hours to design and setup to mill. After that it was on its own for 4-1/2 hours doing the actual work. After that if I had to pull it off and do an hour or two of cleaning, detailing and such..... If done by hand it it would have taken 15+ hours at least to get something truly refined and accurate. Plus I can rescale, flip mill as I mention, without too much added labor on my part. This is where I see a mills strengths and my own expectations from it lay. I think if you expect a truly finished part to "drop out of the tray like on a gumball machine" you will be disappointed. At least at this price range of my machine. Maybe......on a real expensive machine like a haas but I cant believe.... or even comment to be honest. This is also at the discretion and opinion of the beholder. I know some people and companies that would look at this and consider it a finished part. Cut it out slap a joint and catch on there ad we have a pin.

This is in my home shop and will be used for some freelance but more importantly being my grunt worker in making some larger collectable items for my own ventures and enjoyment. I have an advantage in this as it does not have any immediate "business" expectations from it and I can take my time through the learning curve. I bought it for fun with the intent of it making money some day(once I am proficient enough for it to outwork or better yet augment/support the hands on work I do). Obviosly there is and advantage in having worked with these types of machines before with regards to hitting the ground running.

While I am waiting for the 4th axis I am in the process of revamping the shop a bit so that I can build an enclosure, better layout and such. Swarf (chips) go everywhere especially in wax. So the machine has been down for these changes. Once up I am going to attempt 4th axis which I am sure will take some time to setup never mind get the hang of before actually producing a real part. I will update you with that progress. This is probably be what you will need for rings especially ones that are covered in surface detail.

I use:
CAD- Solid works(through work so its free for me but probably a bit too expensive for the home user) Alot of jewelry ppl even companies I know use Rhino 3-D. Its affordable, pwerful for the price and from what I have heard a bit more flexible for the organic designs than a "engineering-design" program like solid works.I think it may also have some sort of NC generator as well. I have only played with the demo a few years ago so someone with some real experience in this may be able to comment better.
CAM- Meshcam(seems to do pretty well for the price range. I havent had it jump through all its hoops yet). I also have a copy of DeskCAM for when I go 4 axis so I cant comment yet. Most of the low cost CAM programs dont offer a 4th axis and I counldnt see at this point dumping as much as the machine cost just to get software to be able to use it.

[surfer93]

that was a nice engraving, may I know the cutter that you used? Thanks for the reply

[under-dog]

It is actually sculptural relief. For 3-D tool paths ball millers seem to be the cutter of choice. I havent tried a straight end mill but i would assume it would make step lines.


It had a roughing toolpath with a 1/8" ball mill at 1/8" stepover. This stepover works fine in wax because it is so soft and cuts so easily. In metal or harder material I am thinking I will opt for a smalller cutter and overlapping stepover so that I remove as much material as possible before the finish pass.

The finish toolpath was with a 1/32" ball mill at .015(just under 1/64") stepover.

I origionally had the file at .01 stepover and it was taking forever so I stopped it, reset the tool to the home for the nc file and ran the updated file from there. According to my simulator it reduce the cut time from 7-3/4 hrs to 4-1/2 hrs. The thing to keep in mind with making files is that everytime you double the resolution it approximately doubles the cut time bec. the cutter has to pass over 2x as much. Depending on the part at a certain point a higher resolution becomes un-noticable. There was not a readily noticable difference between what it cut the first time and with the new file. Not to justify 3+ hours anyway. I am thinking that on smaller pieces I may want a finer stepover though.

[bill south]

Hey Under-dog!
Is the material used for your sculptural wax. I've never seen wax used before and am just curious!!
Thanks.
Bill

[under-dog]

It is jewelers wax. There are afew companies that make it and it is available in three hardnesses. It is good for learning because it is more affordable and hard to break equipment if you screw up. Plus you can to some degree melt down and re-ingot scrap or unwanted parts. Its never the same but hey what are you going to do with the scrap anyways.

1)Green-hard-holds the crispest detail but can be more brittle
2)purple-medium-less detail but more flexible
3)blue-soft-least detail but most flexible

From what I know machinists use a similar if not the same wax alot to test out part files and practice.
I have seen it in the usual machinist supply catalogs(MSC.Travers, etc)

It sells for cheaper than the jewelers wax but only blue is available. From what I can tell it is the same as the jewelers wax. Probably blue for testing parts as it is most forgiving to breakage and the crisp detail needed in jewelry is not needed. It is also available in a wider range of block sizes for making larger parts etc.

Jewelers wax MFG.
Ferris "File-a-wax"
Kerr "carving wax"
I like the ferris as they offer the color spectrum and pre-sliced blocks. This can save time and waste when making smaller parts.

[Stepper Monkey]

I have had experience with a number of CNC mills, using them for cutting jewelry waxes in a production environment. If you can afford it, Model Master makes a bulletproof, very overbuilt system. Ours has not had any adjustment or maintenence problems running daily, and occasionally abusively, for years. The downside is they are pricey, but scary accurate and built like tanks.

The Taig and Sherline seem to be the best of the inexpensive machines. They work well, but need a lot of tinkering and adjustment and occasionally are a pain, but they do 95% of what you need, and will do it 95% of the time, and cost almost nothing. If you do not require absolute reliability and absolutely the fastest, most hassle-free setup (i.e. a demanding production shop environment) then bang-for-the-buck they are a smart buy. Hell, you can buy TWO so you have a backup and still save a boatload of money, the cheaper machines are just a headache to tinker with sometimes. Steer way from the low-end MaxNC stuff though in any case from what little I have dealt with them.

Put all of your money into the BEST design software you can possibly afford, even if it means a lesser quality machine at first.
Unlike other machining, this is really where 90% of your time will be saved or wasted in jewelry design. I cannot stress this enough! Most other CNC machining and routing does NOT require generating a 5 MB g-code (yes, Meg) file for the cutting of a simple 1/4" wide workpiece!!! (for the rest of you in awe of that number, imagine the z-axis behavior alone for a .005 end mill cutting, say, Celtic knotwork rings on a rotary table)
The actual cutting time and machine setup is nothing in comparison. (I use Artcam myself, and it was worth every penny and then some)

[moniker]

Well put StepperMonkey. After 10 years on the bench in retail jewelry and lots of hand carved waxes.My experience in cad jewelry design started with Matrix (GemVision) about 2 1/2 years ago. After 18 months of service bureaus producing our parts in a variety of media ,rapid prototype and wax milling it became apparent we need it done in house. I went with a MiniTech MiniMill 1 Jeweler Package and have been very pleased with the quality of the machine and the parts produced. DeskProto for g code.Granted the learning curve has been quite a challenge. We can now produce all custom jobs in house and have been using some advanced mill strategies.

[opalboy]

Howdy, I've got artcam, and I agree it is expensive but well worth it.
And really design is everything. I have been doing waxes on my roland mdx-15 and it is a great little unit, but my model master 1250 comes next week and it will probably hit the shelf, or come home with me. I'm reel excited.