[Abercrombie]

Hello, I have the opportunity to get a used but good condition Carvewright for $500. I also have experience in building my own CNC machine but I need to to upgrade from what I have. My machine I built is a Frankensteined stepper motor/allthread/roller blade bearing trolley type mostly built from MDF. I have had very good results from it doing 2d v-carving etc.
My question is should I get the Carvewright or build my own? I know that will require more information so here we go divided up:

What I really would like to be able to do:

1. Cut foam,machinist wax,wood including hardwood,billet aluminum, soapstone, and corian
2. Be able to cut bas-relief jewelry and items such as buttons up to guitar bodies and cabinet doors
3. Faster and more precise, and more rigidity than Frankenstein
4. Durability

Must have from the deal;

1. Cut foam, machinist wax, and pine
2. Be able to cut bas relief from button size up to trailer reciever hitch cover size about 5X10
3. Faster than Frankenstein and more precise
4. Durability

What I already have to bring to the game

1. Experience in basics of cnc building from building Frankenstein
2. Stepper motors and controller board
3. Dedicated PC for the controllers
4. Software: Mach 3, Rhino 3d, Z-brush, V-carve, Aspire and Photo V-carve
5. Friend who is excellent tig welder with welder in his home shop right down the street who owes me favors.
6. Aluminum casting if absolutely necessary.
7. Tools including grinders and drill bits and taps
8. Router

Money situation

1. $500 already decided for the Carvewright or for the homebuilt
2. Can without much suffering come up with another $500

What I think I need for this

1. Supported rails and open linear bearings(I am thinking 12 mm) for x and y
2. Multistart acme screws with antibacklash nuts(I am thinking 3/8 2 start)
3. Antibacklash connections from motor to screws
4. Non supported rails and closed bearings for z-axis(am thinking 8mm)
5. cast aluminum 1/2 plate for trolley
6. Steel or aluminum flat bar for frame and gantry(fixed gantry)
7. Billet aluminum for carriage for z axis
8. Possibly spindle

So I would like to have 24X 14X 4(to 6) but can do with as small as 10x5x4

What do you all think is my best bet? Can I do what I would really like for $1000 if not for $500 can I do what I need or is the Carvewright a better idea. I have time and ability, so pros and cons of each. Considering the Carvewright is used there is no type of warranty on either choice. Does anyone know of a good solid chassis with motion already built that would meet my needs?
I know lots of questions but I dont want to blow an opportunity but I also dont want to find i made a mistake. I teach high school and have a couple of kids and a grandkid so I have to take care of where the green goes.
I appreciate any help you might lend.

[Abercrombie]

Aw one more question does anyone have amazingly good sources for the linear motion and leadscrewsa or is Amazon going to be my best bet?

[LeeWay]

Aw one more question does anyone have amazingly good sources for the linear motion and leadscrewsa or is Amazon going to be my best bet?

Hands down look at Ebay first.

[Abercrombie]

It takes me a bit to get my head around metric 12mm rails would be too small for the x and y rails wouldn't they? What size do you all recommend?

[Abercrombie]

Allright with everything I could think of and an extra $200 I came up at $850 to build 20X28X7. That is using supported linear rail and antibacklash 5 start 1/2 Acme. Assuming everything is square and level as it goes together and nice and rigid that brings my question to simply this: Considering I have all of the software I need and i know how to use it would I be better off building an all metal machine myself or buying a $500 Carvewright?

[LeeWay]

I haven't kept up with the Carvewrights, but they do have followers and a forum somewhere I think. Since you have some experience and software already as well as most of the electronics, I think the choice is clear.
Built your own. It will be far more versatile than the CW. Just off the top of my head, the CW is locked into it's own software and does have some size and speed limitations because of the design. You are also basically locked into using CW replacement parts where you can source you own from many different places for a home made machine.
I can' tell you not to buy the CW. It isn't a choice that I would make.