MDO vs. Flatbed

[rubo]

Just an idea for you guys to consider - why not to print on veneer and then mount it on the board? those things are pretty flat. I do that routinely on my homemade flatbed with pinch-rollers- converted Mutoh RJ900, Artbot is right, pinch-rollers suck big time, but it's just an inconvenience - couple of guides on either side of the board take care of skewing - I have none running 12' aluminum sheets. I installed guides on my Epson 9700 - two rubber profiles 3" long, double sided tape - on top of the cover, feed the media through and no more skewing.
As for why making a flatbed vs buying one - it's really simple - the price/maintenance/repair/parts on "proper" flatbed are crazy - there is no reason for a printer to be that expensive - again, Artbot is right, it's just a CNC with a printhead.
OK, got to go back to work. Cheers,

Rubo

 

[artbot]

i have one suggestion. it would require some welding (maybe). say the MDO is 3/4. get some heavy 8' x 3/4" O.D. square aluminum extrusion or steel bar. you might want to weld another supporting u channel that is really heavy to it. you'd want it to be very rigid. now drill/countersink some holes down it. if you run into a bowed sheet. set it on a work table and lightly drill the extrusion at both ends. now clamp the board to the table (over the extrusion) and flatten it. now rescrew the channel down the length of the sheet flush to the top of the sheet.. take off the clamps and possibly the bow in the sheet will be greatly reduced. of course the more rigid the channel, the more it can control the sheet.

 

[DougWestwood]

MDO - lay flat for printing

Hello All!

Have done many MDO boards, and encountered many "banana boards".
Here's how:

Line up warped board with corner marks as close as possible.
Put some kind of weight on each corner. (Gallon jug of waste ink works well).
Turn on table vacuum.
Apply painters tape along the seam between board and table.

This should give you plenty of suction, and create a seal.
Has worked for me for even the most twisted potato chip-style boards.

NOTE: REMOVE CORNER WEIGHTS BEFORE PRINTING!

Rock On!
- Doug Vancouver

 

[TimToad]

For our IONx, we typically do a combination of buying only 2 sided good material, applying pieces of banner tape underneath the panel around the perimeter, covering the rest of our open table area with transfer tape and/or duct taping around the edges of the MDO if the layout isn't a full bleed.

I'm finding that if a customer wants a 4'x8' site sign or less than long term sign and hasn't specifically requested a plywood sign, we offer them direct printed 10mm Coroplast. If they insist on MDO, there aren't 5 or more of them and it is anything between medium longevity and long term in the field, we just print/laminate them on vinyl and mount them.

 

[Techman]

time to invent an automatic height adjuster that keeps the head height perfect to the substrate.

We used to use a machine long ago that would copy a 3D pattern with precision. An on the fly print head adjuster would be just the ticket.