Table size for 49"x24" net cut area.
 

Guys just a quick question about the table size.

I have a limited size garage. i would like to cut 49"x24" boards at a time and what has to be the x and y rail size for this?
i mean how many inches do i have to add to the net cut area to x and y direction?

thanks.

As a quick estimate, add 30" in each dimension to get a sense of the required floor space. Also remember to think about material loading and unloading, and operator space. If you do go with the MechMate, consider a long gantry on a short table. That gives a nice wide loading area, and potentially allows reuse of the gantry on a larger table in the future.

The MechMate design provides excellent stiffness on large scale machines, but as you scale it down, the amount of overhead space starts to dwarf the work space. If you never plan to go larger than quarter sheets, you may want to look at a smaller footprint machine than the MechMate. I think 4'x4' or 2'x8' are as small as I would go with the MM.

Brad,
found out 20 inches to x and y.
You are absolutely right on the larger scale side.
Becouse of the Y car design it does not let you build a smaller scale machine.
i am reading this forum along with the others since a long time. i found out that Mechmate design is absolutely one of the best design out there.
it is sad for me not have a space that i need.

Yes, the MechMate design is great, but you should be able to find an optimal design for the scale you want to build.

Note that 20" is the theoretical no clearance version, and the 5" of padding I added on all sides is a combination of clearance, and allowances for variation in implementation, moving and maintenance access, accessory lines and hoses, and the usual practical concerns that occur.

I will be very impressed if somebody manages to fit a fully provisioned 49" x 24" MM into a 69" x 44" space and operate it comfortably.

Good luck with your build, whatever machine you choose.

If you build a gantry that is 'long enough plus", it can always be re-mounted on a longer table eventually, if that is a long term goal. So building a gantry for 48 to 50" wide cutting then you can build the table the length you need.

The plans indicate what is needed 'exactly' to get given cutting area sizes.

Great thought Jack.
A machine with a 48" Y capacity with a 24" Z length would be much easier to upgrade to a 4x8 than a machine with the 24" Y and 48" Z.

yes all great ideas to get a better machine but the question is still there.
all the axis can be modify to some point but the Y car.
Y car is the heart of this machine and cannot be modify.that what does not let you build a smaller scale machine.i am not going to argue or complain over this great design But

i am sure i will come up with some other y car possibility cuz this limited space war is far from over:)

Can the Y car be modified?
 

Yes. It can be modified. The part that needs to be modified is not the Z-car that runs on the Y-cart but just the Y-cart. It means re-doing wires, extending the 2 Y cart 'rails', carrier box beams, and rack. Basically replacing/rebuilding and re-aligning between the ends of the Y car.

This kind of modification is similar to going to a surgeon to make you taller. They can splice another 6 inches on your legs, but its much easier to be happier to choose to be who you are.

Almost easier to build a new Y car, IMHO, but then, I haven't built one ... yet :-)

yeap.

maybe someday the designer of this machine can scale down the components as much as possible and come up with a new concept design (complete Y car).
now that will be a game changer tough.
that means a new laser files,maybe the mass of the car will be less and some other changes on the v bearings or maybe who knows linear bearing blocks instead v steel rails.
as i say the devil is hidden on that car design.it has a great amount of engineering power and knowledge there.

looks like easy to change and modify but at the end of the day lots of unknown trade secrets.
making a new design i am agree on that but modifying the original design hmmm i am not sure is a good idea sir:)) you are right on that.

GeraldD is the designer. At one time he was going to do something about a fold up 4x4 rig, but it didn't make that much sense given what MM was designed to be.

One guy did build a narrow but long MM. He used it with a long axis to turn logs if I remember right. But I think I remember it being dismantled (lack of need as intended use changed).

MM also depends on the weight of the cars for downward pressure (note that the Y and Z cars don't 'clamp' to their rails like some designs do.

One DIY version is on buildyourcnc.com - they have good plans and kits, but they are NOT MM's. There are other great versions abound.

( I have no ties to buildyourcnc.com - just an example of a reasonable solution I remember )

. . . . not interested to do that

I will offer my opinion. You could in theory scale down the entire scale of the machine that can in turn use a smaller cutting motor. Unfortunately CNC machines require mass or engineering to accommodate for the dynamic forces that are exerted on the machine. A smaller scale machine will also lose out on speed if adequate stabilizing is not accounted for. It is not that you cannot design a small machine that is rigid enough but you most likely will incur the same cost of building a full sized Mechmate that Gerald designed.

There are lots of small machine designs out there. Who looks at a Kenworth and hopes that Kenworth will scale it down for his home garage?

I am in agreement with you Gerald.

...Gosh, I find that I always want a bigger machine - not a smaller one.

Thank you guys.

.....

You mean something like this ??? :eek:

Attachment 15002

:p...... Robert

I want one of those:D!

He gotcha, Gerald. :rolleyes:

now that's awesome truck.not only the commercial guys,others can enjoy too :)

That guy must be a real life 'Jolly Green Giant'.
I wonder how many steaks he eat's a day.