Printrbot Big-E is on sale!
@Brook_Drumm are there any more pictures of this giant?
I can’t recall the name of the rule but, when i started to design my cnc machine, i read you must have a wider base than your Z height can go.
If you don’t some force apply that makes it hard to move along the Y axis.
@Jean-Francois_Talbot at a cnc you neef force to move the cutter bit throu whatever youre cutting. 3d printing is additieve so only the force to move the head is requirerd witch is A whole lot less then A cnc head
This design is certainly good enough for printing, but not Cnc. You would really need linear rails on the y to do any sort of Cnc.
You are right about the force indeed, but would you not, while printing at high speed, say a linear infill at 80%, that the constant back-forth of the infill would have some effect while printing tall structures?
Large format 3D printers aren’t necessarily high speed, when you’re making a thick bead, you can only melt plastic so fast. Even the Cincinnati BAAM doesn’t move very fast.
I was just wondering, because at the speed people want to print these days, something made me questioned the possible print height.
@Jeff_DeMaagd The BAAMCI routinely prints at 250mm/s, can travel at a little over 5,000mm/s, and does 25,000mm/s^2 acceleration. That’s while carrying an enormous pellet extruder system. It’s not just an entirely different class of machine, it’s six or seven classes removed from anything we’re doing. (Some specs: https://groups.google.com/forum/#!starred/3dprintertipstricksreviews/N8gK0KbpYTg)
The Big-E is not designed to print fast in linear feedrate, and yes, it is very limited for scaling in Z. It scales exceptionally well in Y though. If Z height or high acceleration/jerk is important to you, build something else.
This is not meant to be a competitor for the baam machine, just a low cost option for large prints with trade-offs.
I would argue it scales well in X and z too… You just lengthen your y stance that holds the z stage to allow more z height. We should obey any best practices for that geometry. While the current method used gravity to hold the machine down and uses Nema 23 motors, a different approach is possible. Bigger y motors and a carriage that locks the xz stage onto the y rails with more than gravity… Like linear rails or opposing Delrin wheels locked into the side slots on the y rails. This would allow faster speeds and reduce wobble. There is a lot of room for improvement since the cost is so much less. This is currently an absolute proof of concept approach as a mvp (minimum viable product) in mind to put it within the economic reach of mere mortals. If I could fly, defying gravity, at 5mph… I’m not gonna win a race against superman, but it’s still a superpower!
Designing more rigidity or capabilities is easy… You gotta walk before you run. Or crawl maybe. I also don’t assume that BAAM made all the best choices. I am sure they had reasons for their choices based on target market. But I’m targeting regular enthusiasts, not businesses. If I trusted 3D systems or stratasys had made all the right choices for consumer market, I wouldn’t be in business. Or if I thought RepRap machines where good/cheap enough, I never would have formed a company to do things differently. I don’t consider baam as a competitor-- different markets. I think large format printing has been focused on business and I want to prove that consumers have an option to pursue it or at least learn some lessons from attempting it
Brook
Well said Brook. I meant no disrespect with my comments, I simply posted a concern, that is all. Your arguments about evolution are equally right.
After I visited your product page, and seen the wording on it, I have no further comments, you are up front in your sale of the item, and its refreshing to see that much.
Keep on pushing Brook!
I didn’t mean to say it was a competitor to BAAM, just used it in comparison. The video footage I saw didn’t show it in super high speed mode then.