@Eclsnowman a thought just occurred to me that would save on pulleys. If the motor is mounted on the outside with the shaft parallel to the rods one pulley on each (x/y) could be left out. The belt would go, from the motors pulley, above and below the shaft immediately next to it. Connecting to a pulley on the far side smooth rod. The non motor end would remain the same as was to keep the two rods in tandem the night mount could then incorporate a tensioning mechanism (hinge/springs?) beneath it.
This would also cut out the need of two drive belts
Sign me up, I’m very interested.
@D_Rob I think if tension is correct the added belts should not add much slop, and to be honest one of the items I likes best about the Eustatios was how well contained it is within the footprint. To be honest I think it’s worth the cost of some belts.But time will tell once I start printing So far all I have is the frame built and parts printed while I wait for the Aliexpress motors to arrive and the New Azteeg X3 Controller to hit availability.
I haven’t seen many updates on the progress from @Jason_Smith . I see he changed his carriage design from dual extruder to single, and appears to have changes to linear ball bearings verses bronze bushings.
Jason, any input on your experiences so far would be great.
@Ashley_Webster Bed could be changed to three point level. I use that on my Corexy with a much larger bed. For now I just drew it with Jason’s design. As far as springs I still like them. I haven’t had to adjust bed level on weeks of consistent printing. But the build plate on my CoreXY is 1/4" thick aluminum which likely helps with rigidity. Plus springs are nice for some give if you crash the extruder into the bed (if you forget to home before moving around.
@Dale_Dunn funny you should mention that. My new design has a dibond shell that isn’t critical (strictly speaking) but has been integrated into the design from an early stage.
@Eclsnowman I’ll dig out the relevant files over the next few days. I think dual shafts for the cross members on each axis is overkill. A thicker shaft may work just as well. May be worth considering 10mm aluminium instead of steel. There is also the aluminium box section/roller bearing option a la Quadrap.
Hmm. Just looked at the Zortrax again. There is something appealing in the design… Shaft alignment would be critical. It’s possible printed parts might not have high enough tolerances.
@Tim_Rastall I ran into this alignment issue on my corexy with two bearings x 2 shafts. I think one rod with two bearings and one rod with one bearing might do the trick since you only need 3 points to establish a plane.
Looks like its time to play with solidworks stress analysis tools. Looks like I am in for some late night googling on how to use this feature.
@Shauki I know you are one of those true blue real engineer types. If I remember correctly I have seen some posts with you showing solidworks force analysis. If I can get the weights, center of masses, position of the stepper in the assembly, etc this should be fairly easy to confirm proper size/orientation of the rods for a well balanced machine to avoid undue deflection?
@Eclsnowman , First off, great work! Depending on how far your design branches off, I would probably be willing to host your source files on the Eustathios Github & Youmagine pages. @D_Rob , So far, I’ve had no issues with the current belt/pulley setup (other than increased cost), and I’m very happy with the self-contained design. After all, the setup is very similar to the Ultimaker layout, and it certainly has no quality issues.
On another note, I’ve been meaning to take a look at @Tim_Rastall 's xy end/belt clamp design and incorporate it into the Eustathios. That said, I’ve had absolutely no problems with the current design.
@Jason_Smith I’m sure the belt clamp you are using works fine! And I would have done exactly the same thing in order to minimize the number of from-scratch designs you’d have to do. The one I’ve designed was a result of starting again from scratch without needing to worry about securing a spectra line and aligning the cross member with the outer support/drive shaft in order to minimize bending moments and increase Z axis usable space - as much as anything it was a response to @Jarred_Baines talking about how close you can come to a platonic ideal when designing mechanical components.
@Jason_Smith I plan on building it up as you designed it first. Saving that file. Then making my mods. Only changes so far are small rounding changes on dimensions. I am a sucker for whole numbers. So a dimension of 6.1mm would be changed to 6mm when defining the sketch.
Once I get it done I will get you the model in a configuration as close as possible to “stock” as I can for the Github. Could you post a close up picture of how you used the thrust bearings and 8mm collar. I guessed but think I got it right. Also the spring bed mounts were a guess too.
Last question is there seems to be no adjustment designed in for spacing between the 10mm Z support rods. Did you see any issue during assembly with the stack tolerances from the bed assembly causing bind when the bed moves up an down?
You guys are all amazing - longer post when I have time but I would love the SW format files and have seen a few awesome bots with the zortrax “dual rod” design… initially the extra weight seems like an issue but I think the added rigidity is worth it… honestly I’d sacrifice speed for accuracy any day of the week - results from the zortrax are very good… I am really digging the idea of optional bowden/direct drive as well, I’ve just started a new job at a 3D printer shop and I have to say the most rigid machines have the best performance hands-down… a lightweight bowden setup just doesnt compare to a direct drive sitting on 12mm rods, driven by around 10-12mm belts and even being of a more “makerbot” style x/y the rigidity of those components easily over-compensates for the weight of the x motor and direct drive extruders…
Its been a real eye opener actually… here I was, day one, poo-pooing the design of one of the machines in store and it produced some phenomenal prints…
@Tim_Rastall gt2 belt profile can be purchased in widths other than the 6mm common in today’s repraps.
OK its up on github now. Not finished. But getting closer each day. And as of 3min ago my azteeg x3 v2 is on order. Roy has been pretty gracious about me pestering him the last few weeks about the new x3.
@Tim_Rastall as @Eclsnowman says I think theyre gt belts, may be 3 or 5mm pitch, ill have a closer look…
@George_Salgueiro I wouldnt say it was “more accurate”, I was just surprised how much better than the makerbot it is considering its the same carriage style… the bot im speaking of is a profi3dmaker by 3d factories… its fairly expensive - compared to our open source machines, but they are very solidly built, aluminium rather than plastic in most places and thick belts, thick rods, thicker extrusions than ours and dual head direct drive as well as a 1/4" or so bed… its pretty quick considering how much those components weigh and yeilds great quality prints but I havent seen an ultimaker in real life so I can’t comment on the quality vs ultimaker…
@Shauki I am starting to understand your love of rolling vs sliding… it may have more inertia but so much less friction… with good strong belts to control the movement and a strong frame, bearings sound great 
@Shauki , I don’t remember calculating inertia of the small bearings previously (I was just looking at it last night for my extruder carriage, 1.26g each), but I could easily have forgotten. I do remember working out that the 10x10x1 aluminum box tube is both lighter and more rigid than Ø8mm steel rod. Uh, here: https://plus.google.com/116889746506579771100/posts/c1BbZU2eigq