Should I consider building a cnc or just buy one?

[johnt]

I would really like to have a cnc plasma cutter but haven't yet quite justified spending $ 7-10 k for one. I didn't really know building one was an option till I found this forum.
My question is: should I even consider building my own or would I just be wasting money I could put toward a "real" cnc?
I have no clue where to even start, though I am still reading the FAQs etc.
I have no worries about the mechanical/welding aspect of the table, my concern is the electronic/wiring/software part.
I am mechanically inclined and computer literate but not a programmer.
Any help or advise is appreciated. Even some direction toward some reading material to learn what parts are needed.
thanks in advance,
John

[trubleshtr]

Well, like alot of people on this forum, it is a hobby to build from scratch, you learn so much along the way, your bound to make mistakes and it will defffinetly take time, more time to build then buy. If you are going into production with your machine and time is not on your side, I'd recommend buying. But if you are not in a hurry and feel you can tackle the build then deffinetly go for it, You can buy off the shelf cnc kits to put onto your mechanical build, and most companies you buy from will support you and your questions, as-well as the people on this great forum.

*the build would be cheaper but take longer, and may not turn out as "proffesional"(pending your skill level )
*buying would be quick but costly, and you may miss-out on learning new skills.

just my 2cents....

[JRoque]

I'd have to agree with the post above. The electronics, wiring and software business are not that hard. In fact, you can buy that as a package which I'd do if I'd be starting out. Buy the motors (steppers or servos) and the drives (where the motors connect to) from a known and trusted source. Search this site for good sources. The cheapest and fairly good way to go is with steppers and a set of matching drives. You'll also need a power supply and that you can pick up from eBay or other source after you know your motor/drive requirements.

As for software, there are 3 major categories. First you need a way to draw up what you want to cut. Programs like AutoCAD, Rhino, etc can do that. Second, you'll need to translate the drawing to what's call 'cut paths' and that's where Visual Mill, OneCNC, etc come in. Finally, another piece of software takes the path files and tells the motor/drives where to go in an X/Y/Z plane - Mach2, etc will do this part. Some packages do all three of these as well.

JR

[shockwatch]

Hi, I dont want to hijack this thread but I am in the same boat as johnt.

I want to build my own table to keep costs down and at this stage have had little to do with CNC.

I came accross this website offering a Plasma Table Package Deal

http://www.lowcostcncretrofits.com/usa.html

If anyone can make some comments please get back to me.

I intend to make a table capable of accepting 8' by 4' sheets of metal.

Thanks,

Peter Mc

[johnt]

You are not hijacking at all... I appreciate your comments.
Thanks for the input, guys. I will be reading lots more.
I have plenty of time as I dont need to earn a living at this CNC stuff so maybe building is the way to go. I am considering the Torchmate so I would be doing considerable building anyway. If I can buy similar components and "plug-N-play" I may be better off.
Wish me luck,
John

[ViperTX]

Also check out http://www.campbelldesigns.com...I believe he has some sort of Torch control stuff....I suspect that the hardest part you'll face is in the torch and the control of the torch....the rest of the CNC (x-axis, y-axis, z-axis) should be quite easy.

In The Home Shop Machinist (mag) their is a company Plasma CAM at http://www.plasmacam.com that has advertised in the mag for years....research....research..., compare, build versus buy and set a goal!

[Torsten]

I would be tempted to recommend for most people asking this question to
go and buy one.
Building a cnc is a hobby and requires a great deal of dedication, if you don't
enjoy building stuff and rather spend your time elsewhere this is not for you.
I have read that 95 percent of people never complete there machines.
The 3 factors are time, cost and skill.
A lack in any one of them will drive the others up.
If you expect a monetary return for your time invested a homebuild machine will
be more expensive in most cases.
On the other hand if you dont count your time and have some of the skills needed.
You could be building a better machine within a year or more then what you can
buy for.
You may even save a little money on the total of parts purchased dont expect much so.
When doing the cost estimate most just add up the heavy hitter items, in reality
it is the unexpected nickel and dime stuff that ends up driving the cost up.
Because you are indeed asking the question instead of blindly diving in, I suspect
you will do well with your decision.
Good Luck

[accuratemike]

Don't rule out building vs. buying though. I built this http://www.cnczone.com/forums/showthread.php?t=6923 for around $1200, could have been bigger or had Z-axis travel for a few more bucks. I worked on it (not hard) for about 6mos. It is true that the commercially available machines sell for 4-10 times the cost of the sum of their parts. If you can do the work you can save that kind of money. I wanted the machine and could not afford it, necessity is the mother of invention. MIKE

[shockwatch]

Hi, the vendor from lowcostcncretrofits got back to me with an offer I have listed below. Its alot more powerfull however I still have to manufacture the table and other components.

Its it going to cost me about $1800USD for this or I can try and build one for myself from scratch.

I have spent the at three days reading everything to do with building a plasma cutting table and come across Phils Open Source Files on ths forum and another called Campbell Designs, http://www.campbelldesigns.com/

If anyone on the forum can lend me their experience on the pro's and cons of these options please chip in.

Thanks for your time.

Peter Mc
**3 Axis Motion controller with 2 internal opto relays**

**NEW!!! High torque 50vdc / Power Supply**

**Jog Pendant Remote**

**2 / MYCOM 1080oz.in Stepper Motors

**Quickstart CDrom, Demo programs and Instructions**

**Db 25M to Db 25F Printer cord**
high torque 7amp micro stepping 3 axis controller, x2 1300oz.in 34 size stepper motors (Not the standard MAE 1080oz.in type) 50vdc+ power supply for higher torque and top end speed (Not the standard 24vdc type)
Beleive me the upgrades are well worth it!!!

[accuratemike]

Look at the motors here: http://www.clickautomation.com/produ...c=list&cid=159
and the drives here: http://www.geckodrive.com/item.htbml...=&item_id=G201
Depending on the weight of your gantry, these motors are probably overkill. There is no tool load on a torch. You only have to push the torch around. I move a 55+# gantry at around 100ipm with 187oz Mycoms from ClickAutomation. The Opto Isolated break-out boards are around and the powersupply can also be sourced rather inexpensively. You can jog with your keyboard. I would guess that you could get the same array of parts for less than 1/2, but the nice box and pendant will take a little more effort. Look at the DIY-CNC Yahoo group for more pointers to the right suppliers. ( http://groupyahoo.com/group/DIY-CNC/ ) Good hunting, MIKE
PS that is groups.yahoo CNCZone must not like us being able to find the "other guys"

[shockwatch]

Thanks MIKE for the advice. Last night Bob Campbell got back to me via email.

He is designing a plasma cutting table package at this time and should have more details later next month.

In the meantime I will hang around the forums learning as much as I can.

Adios,

Peter Mc

[johnt]

I have been wading through this ocean of cnc information and
I would like some input to see if I've learned what I think I've learned.
Let's assume my plasma table is built and I need to make it move.
Let's also assume the following:
I have
Corel Draw
a computer
Turbo CNC
Gecko Drive
Stepper motors

Is there anything else I need?
Some things seem to be different "flavors" of similar items and I am having trouble sorting through it all.
For example, do I need a G code interpreter or is that where Turbo cnc comes in?
Do I need a breakout board?
Cam? or again is that Turbo cnc? Do I make tool paths and tool offset with TCNC?
Your help is greatly appreciated.
Thanks, John