XYZ CNC Table Dimensions - Which is the most practical for various size material?

[John Kleiber]

This may not be the best place to post this, but it does have to do with engraving so here goes...

I've been looking at CNC bed dimensions and I have a question regarding the most versatile size to accommodate various large material pieces with a smaller bed.

Keeping this simple, lets say I am looking at a 2' Y by 4' X (24" by 48") CNC. The largest in width I can place is 2' Y (24").

However, lets say I have a 4' Y by 2' X (48" by 24") CNC. The largest width I can feed is 4' (48").

Why would anyone buy a 2' Y wide bed when you could buy a 4' Y wide bed, and feed 2' X at a time with proper supports a much larger piece of material?

Generic_CNC_XYZ.png

[Ross Moshinsky]

The simple answer is you need a beefier gantry to span 4ft than 2ft.

[John Kleiber]

The simple answer is you need a beefier gantry to span 4ft than 2ft.

That makes sense. Longer spans would require better support.
The only other issue I could think of, and possibly not an issue with proper heavy frame would be accuracy and repeat ability.

[Art Mann]

CNC Router Parts company sells a 4 by 2 foot machine kit with the Y dimension (in your illustration) being 4 feet. They make it that way so it can be expanded to 4 by 4 foot or perhaps even 4 by 8 foot. The gantry is the same for the 4 by 2 and 4 by 8 machines I think. I certainly agree with Ross's comment.

[John Kleiber]

CNC Router Parts company sells a 4 by 2 foot machine kit with the Y dimension (in your illustration) being 4 feet. They make it that way so it can be expanded to 4 by 4 foot or perhaps even 4 by 8 foot. The gantry is the same for the 4 by 2 and 4 by 8 machines I think. I certainly agree with Ross's comment.

CNC router parts is kinda what started me to thinking what would be the most versatile. Truth be told, if I got a 4'x2' I would probably not enlarge it, rather just get a bigger one and have 2 sizes as long as business was there to support it.

[David Somers]

John....Not implying you should leave the Engravers forum. But were you aware that Sawmill Creek also has a CNC forum? Go up one level and you will find it listed among a number of other good forums. The Engravers forum does have a lot of people who use both CNC and Lasers, among other tools. But the CNC forum will be followed by folks with your specific interest in mind. Another good resource for you if you hadn't seen it already.

[Kev Williams]

This may not be the best place to post this, but it does have to do with engraving so here goes...

I've been looking at CNC bed dimensions and I have a question regarding the most versatile size to accommodate various large material pieces with a smaller bed.

Keeping this simple, lets say I am looking at a 2' Y by 4' X (24" by 48") CNC. The largest in width I can place is 2' Y (24").

However, lets say I have a 4' Y by 2' X (48" by 24") CNC. The largest width I can feed is 4' (48").

Why would anyone buy a 2' Y wide bed when you could buy a 4' Y wide bed, and feed 2' X at a time with proper supports a much larger piece of material?

Generic_CNC_XYZ.png

not to be too nitpicky (ahem ) but the axis's are wrong in this drawing-- X always runs along the gantry...
That said, I've had the pleasure of engraving 8-10' long items in 19" sections, and making sure each next section to engrave is dead-to-rights aligned is time consuming and nerve-wracking. Going to a 4' wide gantry machine would be great, but why limit the other axis to 2', especially if you're plans are to work with 4' x longer-than-2' material? It's do-able of course, but every position change is another chance for a mistake to happen...

[Jerome Stanek]

not to be too nitpicky (ahem ) but the axis's are wrong in this drawing-- X always runs along the gantry...
That said, I've had the pleasure of engraving 8-10' long items in 19" sections, and making sure each next section to engrave is dead-to-rights aligned is time consuming and nerve-wracking. Going to a 4' wide gantry machine would be great, but why limit the other axis to 2', especially if you're plans are to work with 4' x longer-than-2' material? It's do-able of course, but every position change is another chance for a mistake to happen...

On our Bessie's Y is the gantry also my shopbot Y is the gantry