CNC Router Newbie

[IN-WondeR]

I'm planning a build of a rather large CNC router. But I need som advice on material use for tables and gantry's.
I was planning on usin MDF for almost the entire machine, but is it a good material to use for the whole machine.!?
Is it stiff enough if put togehter the right way.!?

I was thinking Moving Gantry made out of 3/4 Inch MDF on the sides, a box in the middle and so on, I think you all know what I mean.

But when I'm thinking of making the table size around 4'x8' would it be stupid to start out by doing one in MDF, should I make it somewhat smaller than this.

I could go as low as 3'x4' would it do to make the whole machine out of MDF then. And would it be precise enough.!?

Next question.

I have already got one stepper from sonceboz. It's a hybrid stepper very nice quality and also very sturdy I think. But is it powerful enough for both X & Y & Z Axis movement. The stepper is a Sonceboz 6600/20 Hybrid Top drive stepper.

I'm already making the plans for the full table including gantry to be built in MDF and I just wanted to make sure that it is possible to make it stiff enough in MDF.

Thx

[ger21]

A 4x8 machine made from MDF is not a good idea. Even 3x4 is on the large size for an MDF machine. Gantry sides made of just 3/4MDF will not be strong enough. At least 2 layers would be needed, or a torsion box type structure.

If you haven't read it, read Joe's thread. It's probably the best example of an MDF machine on this entire site. Joe's CNC Model 2006

Do you have any specs on those motors? I couldn't find any info.

[Madclicker]

I've proven (to myself anyway) that you can build an accurate large router out of wood. You won't do it with 3/4" slab gantry sides, and you won't do it without finishing the MDF. The last thing you want for a finished machine is warped MDF.

It's a ton of work, but you can build as accurately in wood as you can in metal.

[Halfnutz]

Do you want to keep the machine? Are you using MDF only because of cost? You could build a medium size router out of MDF and at a later date migrate the assemblies and parts into a larger aluminum frame.

I ask because there are some great mid size MDF machines here that you could build without having to take any chances with, whereas a 4'x8' MDF machine would be somewhat of an experiment. There might be one somewhere you could use for guidance, but I have never seen one.

For something as large as 4x8 I would not try anything less than 1.5x3.0 aluminum extrusions or 3 inch structural channel iron for the main frame.

[IN-WondeR]

My intital thought's were that this is a stepping guide for me to go up to the 4x8 size router at a later date. For now I'm gonna get into the world of CNC, and then I'm gonna continue building until I reach the 4x8 Size, maybe even Larger if nessecary...

I'm currently working at a facility where we use a 6x10 Laser cutter from Amada. Nice piece of equipment. And when I'm gonna get to where I'm gonna make parts in Metal,then I have the greatest tool to use in this cause I can cut it laser like and with great ease....

But for now, I'm gonna start out with something a bit smaller so I can get the feel of the things concerning CNC.

KM

[diarmaid]

My intital thought's were that this is a stepping guide for me to go up to the 4x8 size router at a later date. For now I'm gonna get into the world of CNC, and then I'm gonna continue building until I reach the 4x8 Size, maybe even Larger if nessecary...
But for now, I'm gonna start out with something a bit smaller so I can get the feel of the things concerning CNC.
KM

It might be too small for you but Im starting out with David Steels sosylva plans just to get the feel of cnc routing. Then I plan to build an 8' x 4' or larger machine from metal. The plans were only $25 but the largest machine in them is 2' x 3'. Its all made from MDF. The plans are very clear and would take less than a month to build, a lot less than that again if you were doing it full time. Might be worth spending a month building it just to get an idea for your larger machine....at least thats my plan, it might not suit you.

The plans are here: http://www.solsylva.com/

[IN-WondeR]

I'm actually trying to get the plans, but somehow my paypal is messed up rigt now. Cause I liked the Design for his machines so I would like to get the feel with those to...

KM

[diarmaid]

You might be interested in this thread and viewing the various links to solsylva threads I posted in it:

www.solsylva.com

[IN-WondeR]

The Plans have now been ordered from SolSylva.com

Nice and easy with paypal... Now all I have to do is wait. And hope that they will arrive nice an looking good also...;-)

I'll let you know when the plans arrive...

KM

[IN-WondeR]

Well now guys....
The plans have arrived in my little brown mailbox. And damn they are comprehensive... I think that's the word I was gonna use... hehe..
The plans are nice, and very easy to follow and easy to set up.
Although one thing. I'm gonna use MDF instead of ordinary wood, I'm hoping to get a more rigid construction that way.

But 7 days from ordering till the plans arrived, that was very nice...
So many thanks to Daniel Steele from SolSylva.com

So now on to the building process... Weeee, my very first CNC...

Kim

[Halfnutz]

What about a real nice 12 ply birch plywood? Is there any general or technical consensus comparing the MDF to plywood? Personaly I like the 12 or 15 ply better than the MDF, just the way it feels and looks, it seems much sturdier, but that doesent mean much, just my personal preference. I'd like to know what the technical spec's compare like.

[diarmaid]

Ply, thats an idea. Would MDF not be 'less' solid than the HDF suggested in the plans, and less solid again than solid wood? Maybe Halfnutz could clarify this? I was thinking a solid hardwood for mine, maybe oak. Then I could sand it down and finish it with a nice clear varnish and it'll look damn good.....