A good CNC Mill to accompany the Desktop?

[wespor]

I have great respect for the community here so I frequently ask your opinion on other products. This time it's small CNC Mills, like the Shapeoko 2, for example.

I need to start cutting intricate patterns in thin brass and I'm not steady on the idea of putting my Desktop through that wear, even if it could, which I imagine it can.

[donek]

Shapeoko is built on makerslide. Along with my two shopbots, I own a CNC Mogul, also built on the maker slide concept. It is not even close to the rigidity of a shopbot. Your desktop is going to be far better at brass and aluminum than any maker slide based tool. If you run your tool paths properly, you will be putting no more stress on the desktop than taking a 1/4in deep pass with a 1/4in diameter end mill in most hard woods.

While there are some less expensive options out there, they are not going to out perform your desktop. Use your machine, take care of it, but there's no reason to baby it. You will find it necessary to baby a maker slide tool though.

[gundog]

What is your budget? Sherline makes some small CNC mills. An Emco is a nice CNC mill. Myself I would buy a larger machine if you have the space. It is easy to make small parts on a large mill but making large parts on a small mill is not easy. You may find you want to make bigger stuff once you have it.

Mike

[wespor]

Ah, I was concerned that the Shapeoko would be too fragile. This (https://www.youtube.com/watch?v=Ig156w0kyaY&feature=share) is the kind of thing I want to do, the mill in the video was a Kickstarter and won't be sold openly until December. It's around $2,500 and I guess that's about the top of my budget. I may end up waiting and buying that.

I will try on my Desktop first but I'm concerned about lead content, I'll be making jewelry and most machinable brass is soften with lead, up to 5%. I'd rather avoid that.

[Ger21]

You'd probably be much better off with a Taig or Sherline. While they call them mills, none of these other machines are what I'd consider a mill suitable for cutting metals. Machine's like the Shapeoko are little more than toys.

[donek]

Ah, I was concerned that the Shapeoko would be too fragile. This (https://www.youtube.com/watch?v=Ig156w0kyaY&feature=share) is the kind of thing I want to do, the mill in the video was a Kickstarter and won't be sold openly until December. It's around $2,500 and I guess that's about the top of my budget. I may end up waiting and buying that.

I will try on my Desktop first but I'm concerned about lead content, I'll be making jewelry and most machinable brass is soften with lead, up to 5%. I'd rather avoid that.

Any idea what the hot melt is that's being used?

[wespor]

Any idea what the hot melt is that's being used?

Waiting on a reply back about that, I also asked exactly what brass was used.

[donek]

Waiting on a reply back about that, I also asked exactly what brass was used.

It's possible that it's just candle wax, but an interesting hold down technique for one off metal parts as long as you can keep them cool.

[Burkhardt]

I believe it is fixturing wax like THAT (http://www.machinablewax.com/product.php?product=44)

As for brass you can check for lead free naval brass but even more important make sure it is nickel free.

[scottp55]

Not positive , but you could probably use dop wax like I use for some opal 160F.
Dipping a 1/4" birch dowel into it and then pressing on stone, lets me go from 180G-60,000G polishing and (NOT OPAL) sticking it in the freezer for a minute and the stone pops off.
Just thinking. Many kinds of dopping wax.
http://www.riogrande.com/Product/Super-Hard-Green-Dop-Wax/206054?Pos=18

[Brady Watson]

....as long as you can keep them cool.

The most important point...and not quite as easy to achieve unless you are cutting thin parts. Thicker parts get heat soaked and would chuck your part across the table and laugh at you if using wax as a hold down. Even carpet tape fails with thicker metal parts that get heat soaked.

Unless you are cutting critical mechanical parts, you can go pretty far with any model SB when it comes to machining non-ferrous. Yes, some allowances have to be made, and no it isn't going to be fast, but you really can do quite a lot.

As long as you NEVER plunge straight down (ramp your entries) and use the proper tooling, you can do amazing things.

-B

[gundog]

If you have the money Tormach makes some good small CNC stuff and they have a good forum on CNC Zone that gets a lot of posts. New Tormachs start around 9K and I have seen used ones go for around 5K.

Mike