Well spotted in the video, I just took another look and you're quite right, they aren't using the Stepcraft for that tutorial. I had assumed given the other tutorial on CNC machining carbon flat sheet that they were using the same machine in-house, so glad you picked that up! 

Ok, well I shall probably rethink this then and stick to the traditional manual methods. Appreciate the input oekmont!

Have a look at ec's video again. This is no stepcraft machine. It is hard to tell what kind of machine it is, but it looks like some China machines I saw on eBay. At least it should have unsupported rail bearings, or even supported. The second would would be the lowest standard i would be looking for. And it definitely has a more powerful spindle.
If you got no need for precision, a stepcraft might be ok, but it will take a stepcraft much longer than the machine in the video. If an x-carve could achieve those results, I don't know. I doubt it.

I would not go as far as to recommend a stepcraft for 3d milling. Compared to the x-carve the stepcraft machines are real rigidity monsters. However, mechanically even the stepcraft are closer to 3d printers than to proper cnc machines. And I am not talking about industrial steel machining. Stepcraft is very expensive for what you get.
Have a look at sorotec.de. starting  with the basic line, this are the kind of machines I would be looking for. Sorotec might not be an option in Australia, but there should be people building cnc machines like that. What you should look for, in my opinion, are proper linear bearings (wich both x-carve and stepcraft are missing) and  ball screws (same here, stepcraft has at least screws, belts are not suited for any cnc milling in my opinion), And a stiff portal (is that the right word in English?) (Here, the smaller stepcrafts might be ok,  but the x-carve is falling way behind). Additionally, usb has got a real bad reputation in the cnc community, because it might cause some problems. I would go for parallel port, if the budged is tight. Also I would like to mention, that a cheap desktop pc will be an advantage when it comes to cnc working. The energy saving systems of laptops can cause some quite strange problems.

Well, I didn't mean to turn this into a discussion on machine suitability, but what is your opinion on the Stepcraft then? I can stretch the budget for a Stepcraft, and knowing that EC are using it for what I want to do with it makes it appealing as well, but I just can't really see much difference between the two from my - admittedly very inexperienced - perspective. I know the Stepcraft will have better quality components, but I'm not sold on whether they are actually necessary. The covered bearings are nice, but it's a half hour job to make something similar for the X-Carve. It's stiffer, but again I'm not opposed to just stiffening the frame of the X-Carve if I find it is loosing steps. 

Realistically, it's 2.5x the price of the X-Carve, and a lot of that will be due to it's flexibility (function wise, not stiffness wise) which I don't need. But is there a reason the Stepcraft can do 3D routing of tooling board, and the X-Carve would never be able to? To me, it looks like the X-Carve can be modified to do what I need it to, comes with a bigger bed, and still comes in at less than half the price of the Stepcraft?

To be fair, I am looking at this as a way to reduce my manual pattern making. Hand carving polyurethane foam, even with the 2D profile skeleton structure, can only be so accurate. So I'm only really looking to replicate those tolerances, I'm not trying to get into precision milling of high performance engine components. 

I can only tell you my opinion based on my experience. I would not go for either a belt driven or non proper liniar rail machine when looking for 3d routing or carving materials harder than softer wood. The x-carve has both, and an not very smart construction on top of that. The portal is so soft, it twists visible by just driving the router into it's middle. And a z extention will make this even worse. And just slower isn't always the answer. I can tell you, that the vibrations both from the belts and from the flex will ruin your surface at least in a way, that you should start sanding with 120 grit paper.
And stiffening it... well, the construction is so bad, why should you try to fix it, if a good solution isn't that hard at all. maybe the improvements make it a good machine. But someone who thinks that the x-carve is a solid base to start a machine from with some improvements, has at least a different understanding of a good cnc router than me.
The x-carve is a low budget and router for 2d cutting of soft materials. Even the producer says so. Every construction detail is made with this in mind. from the very weak open loop steppers to the cheap bearings. It is not just the stiffness

I should clarify; the machine I'm getting isn't an X-Carve from Inventables, it's a locally made machine called the XYZ Carve. The makers 3DTek basically buy the X-Carve mechanical kits and modify them to improve them, combining their favourite aspects of the X-Carve, the Shapeoko 2, and Chinese kits.

So for example, the Z-axis as standard has 100mm travel but 65mm clearance under the X carriage. This can be improved to just under 150mm when ordering. 

As far as stiffening up the frame, it isn't hard or expensive to stiffen up the extrusions. The Y rails just need bracing to the bottom t-tracks, and the X rail can be stiffened up with an I-beam. I think realistically if that is still too flexible then you should be dropping the speed and depth of the cuts to take some strain off.

I would absolutely not recommend a x-carve for accurate cnc work, escecialy not for 3d work. The X-carve is the least stiffest cnc router I have seen so far. You might get along with it, as long as you are just doeing 2d and you are not looking for real precision.
Stiffness is a big thing for cnc machines, because of cutting forces and vibrations. As long as you are just 2d-ing you are usually not looking for perfect finish around the part, and a few 1/10 here and there might not be a problem. 3d however is different. In my opinion, you won't get a usable surface with a x-carve. Additionally the x-carve got a very limited z-axis. So just from the dimensions, the x-carve is not suited for 3d moulding.
Even the basic eBay chinese cnc machines will outperform a x-carve in terms of stiffness, accuracy and z-axis travel length. Sadly, in my opinion, there is no real cheap cnc option for 3d mould routing. I would say the cheapest system I can imagine to work is about 3-5k euro. Including tools and a cheap pc for controlling

Hey guys,

I'm thinking about investing in an X-Carve system, as I have managed to find a local source of an equivalent product to the S120, so working with tooling board is all of a sudden a lot more of an option for me and I'm particularly interested in the production of tools for low volume production runs to reduce my manual workload a bit. I'm probably trying to run before I walk here given I haven't managed to sort out my issues with the XT135 yet, but still - I'm easily excited!

I wanted to see if I could get a bit more info on the actual setup for machining tooling board though, ie. what sort of bits would you recommend, what spindle speeds should I be looking at, do you find the feed rates etc. in the data sheets to be good or would you recommend playing with them, what is the thinnest material thickness you would recommend machining to (eg, if I have a 100mm piece of tooling board, what depth am I limited to before it becomes to brittle to use?). Although I've got my head around CAD design with F360, I've got no experience with CAM what-so-ever so I'm sure I've got a lot of playing around to do before I'm anywhere near ready to start messing around with tooling board, but I would just like to understand the process a bit better before I commit to the X-Carve.

It's good to see the cnc approach becoming more accessible as time goes by. I've spent a whole heap of time researching what machine I should buy but usually I end up doing nothing because I doubt I'd be happy with what I can afford. Most of these little ones seem pretty flimsy and I'd like the be able work with ally etc as well as tooling board and achieve good accuracy. Will have another poke at it sometime soon. Inspiring vid though, good work.

Matt Statham
Easy Composites / Carbon Mods - Technical Sales