Jewelry Making??

[its_me]

Hello,

Allright i want a shopbot cnc router but i have a couple of questions. Can you create wax molds with a router or is it just better to do with a mill? Is it better to engrave with a mill or a cnc router? Basically i want to create jewelry molds but i want to do other things too like make furniture and engrave and a cnc mill would not have enough space for what i want to do and i dont really want to get two different machines. So tell me what you think is it possible to do these things on a cnc router with a 4th axis?

Thanks i appreciate you answering my questions and look foward to some good answers.

John

[frank_hav]

John, are you talking Spindle vs Router or Machine vs Machine?

I would choose the spindle for the variable speeds.

As far as machines go routers and mills are both capable of machining about anything within their tolerance zone. Mills are generally expected to be more rigid as they are expected to mill ferrus metals also.

My bot does fine on Wood, Plastic, Aluminum, Brass, Foam, and Wax. Keep in mind that small engravings require small bits. With this in mind you will want as much variable RPM as you can afford. You also need to pay close attention to CHIP LOAD, as little mills break easily.

Just to repeat, either machine will work as long as your part is within the machine tolerances, and you don't plan on cutting alot of steel.

Frank

[gerald_d]

Making jewelry and furniture on the same machine is just not right. The ShopBot is a furniture machine and not a jewelry machine.

[patricktoomey]

John,

As someone who uses a ShopBot to make custom cabinets as well as 3d relief carvings and custom millwork I can give you some insight. As a furniture machine the ShopBot is fantastic and can't be beat for the price. For relatively detailed 3d work it is very good also and I couldn't find an equal out there anywhere. If you are talking REALLY detailed work though, like wax molds for jewelry I don't think it's the right machine.

The reason I say this is that there are physical properties of the machine that just don't lend themselves to this sort of work. The ShopBot is relatively lightweight and therefore likes to shake on rapid movements and direction changes. It is not very rigid, compared to a mill or a stiffer (and much more expensive) machine. This lack of rigidity allows the cutter to wag around a little under loads and movements. For the work it is intended to do, these factors are not an issue. For very detailed work however these become huge issues. One more problem would be resolution which is in the 5/1000" to 15/1000" range depending on what you're measuring (repeatability, positional, etc.) 5/1000's is huge in a piece of jewelry. Many high resolution mills that I've looked at for very detailed work are in the 0.5/1000" range so you get 10 times the resolution and a much stiffer machine that won't overshoot or vibrate on cuts.

You could theoretically change controllers, motors , gearing or rack and pinion ratios to increase resolution but your speed will plummet and you still have the other issues. If you get a machine that's accurate to 0.5/1000" chances are it's much smaller and/or much slower or priced like a small house so I don't think one machine for both uses is plausible.

Building your own machine would be the only other possibility but I think it would be a huge challenge to build one that could do both types of work efficiently. It would be like trying to buy a car that you can race professionally on the weekends and also drive the kids to school and pickup groceries with during the week.

I hope I've given you some info you can use.