Quote Originally Posted by lebies View Post
Thanks for this detailed answer, very much appreciated.

I'm not a mechanical engineer, so the best way for me to learn is by burning my fingers. To do so I guess I must expose my weaknesses but have the balls to put it out there and trust folks with experience will come to the rescue - as has been the case here (thanks all). Collectively that makes of us a better, stronger community. I look forward to when I can start contributing and in so doing free up the folks with their vast knowledge to spend more (quality) time innovating and have drones like me help newbies get going .

On to the business at hand.

Not sure you saw my revisions (we posted at around the same time) but I've made some significant changes to the original. I went back to one of my 1st designs and have decided to go all steel.



Nothing to loose and much to gain, will implement.




Done. I cut it down to even less. In fact 150mm diameter is probably more than enough for my needs.



Thanks, will do.



I'm going Hiwin 20 on everything now.



Fred and I are speaking and sounds like we'll come up with a solution. Ridiculous thing is, for a set of ballscrews at $90, DHL want to charge $92 for shipping!
If we're going to find a good shipping solution between us, my costs drop to the extent I can use Servos and an alu bed.



I'm going to buy the alu bed piece-meal over the next few months, so I'll work to it in good time and give it high priority.




Will now go less radius as stated, but I can't quite picture what you actually mean here :).




I was definitely inspired by their builds, hence the strategy on the alu bed in good time. Also, I've now got the message - go overboard on the base, it's worth it!



Thanks to Eddy (and locating his stiffness calculator) I was able to learn a whole hellova lot, and improve on my original design. Mostly though, many of the critical principles were highlighted for me to learn from and/or about.



Great! I'm going to use this combo myself. Just busy sourcing motors to match.



As stated above, once these things have been pointed out, it's easy enough to pick up on. Without Eddy's sheet (and/or knowledge thereof) I'd have been fumbling around in the dark for quite some time I can tell you. As a suggestion (very humbly), a place to put all such info in it's own right on the main board?

Thankfully there's a community of very helpful folks to nudge one in the right direction, and once you've found the proper info, you can actually do precisely what you recommend .

Thanks again for the detail, really appreciate and it'll definitely shorten my build time.
Quote Originally Posted by silyavski View Post
Thats why the suggestion to buy everything from him, cause shipping costs are high, so they could be spread among all pieces. i have done the calc and seems cheaper to buy all, pay shipping, duty, than buy from Europe, where i live. 1/3rd cheaper. you will have to do your calc though. Dont forget to tell him to state lower value.




i mean this, the green is the 300mm diameter workpiece

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Gotcha, thanks.

Been buying all my electronics from China for a while now, so have learned a few tricks :).

I'm thinking of pairing the AM882 with 86HS35 steppers. Good match?

Not sure I should belt-drive both X-axis ballscrews from one motor, or drive each individually.
If I go belt-driven both from 1 motor, I'll go look out around here for some examples.

If I go individual drives, what size motor should I be thinking of?