Overwhealmed Newbie Looking for advice...

[fjcruiser]

Ok, so I've got the CNC bug but I'm so new to it I'm overwhealmed!!
My objective: use CNC 2 axis in conjunction with plasma cutter to produce misc. steel brackets and such

My dad's objective: use whichever CNC machine (4 axis?) to produce misc. routered/carved solutions. He wants to be able to create corbels and fancy columns like the following pics... http://barscigarsandbrew.com/Merchan...roduct_Count=4
How many axis will it take to produce these results? Is he wanting something that is not attainable without going industrial??

I've been poking around here and I'm getting overwhealmed with the abundance of knowlege/options with respect to CNC'ing.

I am an avid 2/3D AutoCAD user (mainly Architectural) and curious if all designs produced in AutoCAD can export/be coded to be read by the CNC controller?

I hope all that made sense. That said, where is the best place (besides here) to learn A-Z about CNC'ing? Is it a bad idea to try to use the same machine to do Plasma cutting (steel) and routing/carving wood?

I'm reluctant to even ask as I see the majority of this forum revolves around building your own machine, but are Torchmate machines any good? Will they produce decent routing/carving results?

What is the best/most cabable and complete CNC machine available that is capable of doing what we are wanting?

Sorry for this crazy disorganized post, but I appreciate any info/responses!

[keebler303]

Welcome to the Zone.
I recognize your name from pirate, so as they would say, read up!

1) Are you looking to build or to buy?
building is cheaper but you will inherently have some things to work out. buying will cost more but you will get a reliable system from the start.

2) The plasma table will be easy enough to figure out what you want. Sift through the plasma forum and you will get a good idea of what you are looking for.
http://www.cnczone.com/forums/cnc_plasma_waterjet_machines/

3) For the fancy carvings and such you will need a 4 axis machine. This will be a definate step up in complexity and cost compared to the plasma table. A commercial unit capable of 4 axis carving is pretty pricey. Check out this site for a look at what is needed for 4 axis column carving.
http://turningaround.org/4_axis_mill.htm
art ransom is the author of that site and he is a member here.

4) as far as putting them both together, you will have tradeoffs to make it work for both. it is a matter of wat will be acceptable to you and your dad. After you check out some examples of separate machines you will be able to decide if you think you will be happy with a combo machine.

Shopbot is a pretty nice setup and they have a setup that would work for your combo machine. Here are the standard 3 axis routers, which you could use for your plasma and any flat wood work with a router attached.
http://www.shopbottools.com/prtstandard.htm

then for the 4th axis for the columns you could bolt this on and go to town.
http://www.shopbottools.com/accessories.htm

5) your autocad drawings will be adequate for your parts. You will need a dxf for most 2d parts which will be opened up with a CAM software. sheetcam would be good for plasma and is cheap. Surfcam, Visual Mill or others capable of 4 axis stuff will be pricier.
http://www.sheetcam.com/
http://www.surfware.com/
http://www.mecsoft.com/Mec/Products/products.shtml

The CAM software generates the code needed for the controller, which actually tells the machine where to go.

Everything you need to know is here, it just takes time to read up and digest it all.

Good Luck
Matt

[fjcruiser]

Yup, this was my name on Pirate before the FJcruiser was even a concept car!

I reallize i double posted, but can't seem to delete the post? I thought it was under the "Edit" button but i can't find it. Advice?

My dad wants to purchase a whole machine for simplicity but I'm partial to piecing one together. Does anyone make a good "out of box system" that is 4-axis?

Thanks for the reply! I'll be reading all night!

[keebler303]

the shopbot stuff I mentioned is pretty much "out of the box" you would just need to figure out an easy way to switch between router and plasma, and your table/bed would need to be compatible with fire and still be good enough for wood. Maybe a metal table with a wood table to go over top when working on wood.

I am sure there are plenty of similar machines to shopbot to compare and shop around, I am using it as an example because my dad has a 4'x8' router from them.

Matt

[fjcruiser]

Shopbot looks very promising. I was thinking of a similar table to what you're describing. One with slats for plasma and bolt down a sheet of MDF to those slats for routing. Whats the biggest difference between that and the "MechMate" seen here http://www.mechmate.com/Forum/messages/329/646.html ? Just size and beef?

[keebler303]

Look fairly similar, beef is the only difference I see, and the planetary gear reducers on the stepper motors, probly needed for extra torque to move the beef.

Matt

[aspenelm]

Welcome. Sounds ambitious and open ended. Spend a few days reading this site, and decide if you want to make or buy a cnc machine, and define your needs and budget as well.

There seems to be a common trend, many build an mdf/plywood framed machine to get started, to see if they like it, get more experience with software and electronics, etc...Then they will upgrade to a second machine usually with a metal frame, sometimes transferring their motors and controller to the new one.

A basic three axis machine can get you pretty far. It can't make undercuts. But it can 3d carvings. To do the columns, you would need 4 axis minimum, probably 5 axis for the level of detail of the the column in the link. I think you will find that the software (4,5 axis) is much harder than the hardware and quite expensive.

Personally I would not mix Plasma and Wood Routing on the same machine.

To get a "cutting path", you'll need some form of CAM software. Again some time reading through this site can help you narrow this down. Any questions please ask.

[ger21]

Originally Posted by fjcruiser I'm an avid AutoCAD user (2/3D) and I have some experience with 3dMax. What conversions would have to be made to create a "cutting path" that is readable to the machine?

If you have AutoCAD 2002 or newer, I wrote a macro that will export g-code from within AutoCAD. There's a link in the thread. AutoCAD 2 G-Code macro

As for the limitations of a 3 axis machine, the main thing is that you can't do undercuts. You can sometimes work around this by using fixtures to hold your work at different angles to machine it from the sides.

[mulligan]

Originally Posted by aspenelm Personally I would not mix Plasma and Wood Routing on the same machine.

I'm in the process of ordering my parts for my 4'x8' CNC table and want to use both Plasma and Router.

I'm curious to know why this would not be a good idea? I've been reading and reading this forum for a year now and the only reasoning I can find is the IPM difference.

That said, what IPM are required for Plasma and Router?? 130 IPM for plasma and 80IPM for router. Of course this depends on the material used, just looking for a ball park number. Another thing I can't quite find a concrete answer on.

I am ready to hit the button and purchase the Xylotex 3 axis kit with the 269 oz/in motors. Will these work? I have no problem with changing pulley size to alter the gearing depending on the material I am working (wood or metal).

TIA

[keebler303]

my concern with mixing plasma and wood router would be getting all the dust and wood scraps away from the plasma so there is no fire. Also if you use the plasma, everything gets covered in metal dust. Not quite what you want all over your nice wood pieces. Basically plasma is really hot and dirty, which is not what you want around nice woodworking projects.

Try it and see how it works out. As long as you keep things clean I would think it will work ok.

My $.02

Matt

[ger21]

Sawdust + Plasma =

For a 4x8 router table you'll want to have at least 300ipm rapids, or you'll get bored fast waiting a minute for the router to move from one end to the other.

A Xylotex is a poor choice for a 4x8 machine. It just doesn't provide enough power.

[mulligan]

Originally Posted by ger21 Sawdust + Plasma = For a 4x8 router table you'll want to have at least 300ipm rapids, or you'll get bored fast waiting a minute for the router to move from one end to the other. A Xylotex is a poor choice for a 4x8 machine. It just doesn't provide enough power.

Understood. How many IPM for Plasma? Which motors would you reccomend so that I can achieve both?

I can deal with the dirt issue quite easily. I'm not too concerned about it since I will primarily be after steel products, and want the option for wood also.