great tool, if you want to add our laser on it, I would be happy to give you 25%

http://endurancelasers.com/

great project .  for friction rollers , i suggest you have a look at the types of rubber hose that can be found in your hardware store .  neoprene and silicone type rubbers make good friction surfaces . 
also one should look at LPG (propane) rubber tubing ,  some of that has 6 to 8mm center hole and about 11 to 14mm outer dia.  cut into 1cm or so and pushed onto a 6mm or 8mm smooth rod  makes them pretty good friction rollers .  I use salvaged tube from old broken regulators , but there can be a lingering stink of pro pane for a few days , so try to find new in your hardware store if you can .   so neoprene for small rollers ( you can get this at hobby shops for R/C air craft and cars  fuel line as well  if you hardware store does not have it . 2.5mm ID and ~4 to 5mm OD ) 

can you give me grbl setting  please

how can i find my ramps 1.4 shiel- arduino mega for grbl source code

allright. i know that my english is bad. so i am sory. i want to learn thing; i have ramps 1.4 card, arduino mega, polulu shield. for this system, am i make config to  grbl. And i want to work solenoid in my system. i don't know how to do. this is final project so can you help me please

hi can you help me for frimware

Download https://github.com/grbl/grbl

And extract it into your libraries arduino folder --> Open the 'Arduino IDE' and go to examples, pick GRBL and hit upload to you Arduino Uno..

Maybe I don't quite understand the question though..

OK so you used a printer feeder rod from an old printer. Just by looking at the design, the gear controlling that rod fits a variety of sizes right? ie: you can fit different rods with an adjusting screw? Also where are those betls attached to the stepper motors from? Great build!

Hi. Thank you for your interest!

Yes the feeder rod is from an old printer, and the current size is Ø5mm. I just updated the files on thingiverse, and marked which diameters to change, be aware that you have to change both the 3mm and 5mm sheet. (Marked with green).

I bought my timing belts here:

http://reprap.me/hardware/belt-gt2.html

http://reprap.me/hardware/pulley-t2-5.html

although I have downloaded the files to get them LASER CUT... but do you have suggestion for a similar one where motors stay still... not talking about the one where the pen hangs and I have seen the corexy.com but the laser files are a bit confusing for me and I cannot get it water jet, only laser cut....

Uhmm, not quite sure I understand the question. But thank for the link to the corexy, haven't seen that one. If I understand you correct, you want a more "standard" XY-table that can be made with a laser cutter? What is your application?

OMG!!! This is just what I'm looking for. I actually have a 30K worth of junk laying around that used to be a machine that cut out shapes in rubber blanket. The same principle.

do you need to home the axis?

Yes, there is no automatic homing just yes. But I will put it on the todo.

So you need to cut both the 3mm and 5mm parts? How large is the 3mm part? How large are the dxf files in inches? BigBLueSaw quote thinks ithe 5mm parts 581 in x 132 inches?

Yes, you need both the 3mm and the 5mm pieces. Using 3mm for everything makes a very fragile printer. (Have made somewhere around 10 in 3mm)

The file is in mm

May I suggest using RTV silicone as friction material for your paper feeder mechanism? I don't know if it will work (having never done this) but I thought it might be a helpful idea.

Nice job with this project. I might just have to try something like this once my current laser printer dies.

Thank you!