Feeling "In" way over my head

[alwaddell1723]

Hi,
I've been lurking here for a long time, have a goal of building my own CNC wood routing table, why, because I have lots of shop skills, reasonably good equipment to work with, and not a lot of money. So finally, I thought I'd spend some serious time on the site looking for info to help me get started in my project and I'm more lost and confused than when I started. For example - I keep getting this message that I've belonged to the site for a long time but have never posted..... and it took me 15 minutes just to figure out how to find the CNCzone ClubHouse forum to post this message. Can't even imagine how many gray cells I would burn up trying to figure out how to build something.

No, I'm not complaining about the site, it's probably a fantastic resource to those who know what they're doing, and also really helpful if you have the inclination to read through countless forums and try to figure out what applies to your situation. But I don't have hours ti spend on the computer and I don't know much of anything about CNC routers, just that I figure I can build one given good drawings and concise step-by-step instructions from start to finished, operating machine. Yes, I looked at the fantastic, beautiful drawings for an open-source design by "JGRO", they look great and the price for them is perfect, but no way could I build that without some very clear instructions.

So, here's what I'm looking for. Maybe someone can steer me in the right direction:
I want a to build a CNC router table that will use a commercially available wood router (Bosch, Rockwell, etc) to cut 3/4" thick oak into cutting board-style shapes. Max finished length 18", max width 6 inches. If the machine is bigger, no big deal, but scale-able plans would be nice. Since it is cutting a full outline of the object in one pass, I guess there would need to be some kind of vacuum hold down of the wood, otherwise the router would not be able to cut fully around the object in one continuous path?
I have both MAC and PC computers, I have a 3-D drawing program (Graphite 8) that I use to design the objects that I want to cut on and that will export those drawings in these formats: Graphite, PDF, DWG, DXF.

I can cut, grind, sand and drill wood, steel, aluminum, plastic, tap holes, weld steel, solder wires, and read and follow instructions accurately.

I don't mind paying for plans if they will get me where I want to go. I don't mind buying the electronics if they are the right ones for the job and the plans tell me what to buy.

Hopefully someone(s) can steer me in the right direction, then I'll be posting pics about the machine that I built.

Thanks,
Al

[jalessi]

Al,

Welcome to the zone.

What kind of accuracy do your parts require?

Is it for production parts or hobby?

What is your budget?



Jeff...

[TOTALLYRC]

Hi AL,
Grahite is a great program to draw your parts in. You will output the data, most likely in a dxf format to get into the cam software which generates G-code.

Which machine and which electronics we be dicatated by you budget more than anything else.

As a for instance a g540 kit from Keling is a nice place to start but may be way over your budget.
It may be a little overkill for the size you are talking about but it will definitely be capable of driving it in style and if your size gets bigger it will still work.

The questions jalessi asks will help us get a feel for what you truly need to get the job done.

It can be very helpful to find a buddy to work with who maybe has a mill and/or lathe or who can drink beer with you when you feel the need to burn the machine to the ground while you are putting it together.

Mike

[alwaddell1723]

Hi Guys,
Good questions. For accuracy I'd guess plus or minus .010. But it's not really critical. I'm cutting out stand-alone wood parts that don't have to fit with anything else. As long as straight lines don't look wobbly to the eye, and there's no misalignment where the cutter started cutting around the part and ended up finishing the cut, no big deal.

As far as hobby vs. production, I would have to say I'm more of a hobby shop. I make these things to give away to friends and sell a few at craft fairs.

Budget? Around $1500? Machine and electronics, not counting cost of computers which I already have.

Hair loss? Already too late! Been bald for years.

Thanks,
Al

[fatal-exception]

Well Al, that's the thing about a DIY machine. Nobody is going to have complete plans from mechanical to electrical to software for exactly what you want. I too felt overwhelmed and confused when I first started to get into this a number of years ago, but that goes away the more you learn about the art of CNC.

The only way you will become elightened is to read, view pictures and videos about each and every aspect of building a CNC machine. If you can't put in monitor time to do this, you would probably be better off buying a machine and spending your time learning the software for creating g-code and the software for controlling the machine.

Building a well behaved machine is a considerable process that takes time. Nobody is going to tell you exactly what to do. It's your machine.

Some main things to consider:
Machine:
1. What's it made out of? (Steel or aluminum?)
2. How are the parts going to move freely? (Linear rails, v-rollers, chain and sprockets, ect)
3. How are the parts going to be moved? (ball screws, belts, chain and sprockets, acme screws, ect)
4. How big do you need it? (you already know this)

Electronics:
1. Steppers or servos? (Tons of threads about this here already)
2. What kind of drivers for the motors?
3. What size of power supply?
4. How capable of a break out board?
5. Limit and/or home switches?
6. Type of spindle?

Software:
1. Design software for drawing parts? Cobalt will work fine for that.
2. G-Code generator software? (Artcam, SheetCAM, and the dozen or so other CAM programs available)
3. Machine control software? (Mach3, EMC, TurboCNC, ect)

You will find that cost will be the major factor in how solid a machine you can build.

Enjoy the journey...
Paul

[lsalme]

I scaled down Joes 4X4 CNC to 4X3 due to garage space. You could easily scale it smaller and save big since your buying shorter extrusions and leadscrews. As for cutting your periphery's you can make your cut depth .020 or so short to leave material that will hold the part in place.

[lovebugjunkie]

This might give you an idea, I have affiliation with the site other than I am going to order some parts soon.


http://cncrouterparts.com/product_in...products_id=49

[Edwardo]

Have you checked out www.mechmate.com they have the drawings for a table and .dxf files to have all the parts cut for the gantry cut and its free to down load, i already have a cnc plasma but in the future if i build a cnc router it will be a mechmate... hope this helps

EDD