Thank you for your information, Mike. I will think about it.
For rack and pinion, I found the Nexen roll and pinion interesting. But I expect your solution more maintainable and easier to implement.
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Thank you for your information, Mike. I will think about it.
For rack and pinion, I found the Nexen roll and pinion interesting. But I expect your solution more maintainable and easier to implement.
Did you measure how much the backlash varies? If the backlash is software corrected, there will be some variation left. Is T5 better than GT e. g. in this respect?Quote:
Originally Posted by Mike Everman
Sorry, being lazy but I didn’t want to read through all 29 pages of this thread. Is there a website where this is sold?
Thanks!
What gear down ratio are you planning on using?Quote:
Originally Posted by JoergS5
I am considering GT2 10mm in both sides, 20 teeth and those motors with a 5:1 ratio.
Freies schiff 3 stücke 4-Blei NEMA 23 reduktion getriebe Stepper Motor, Getriebe verhältnis 15:1, 20n. m
https://s.click.aliexpress.com/e/b834MfFE
The second option is just one 3nm stepper in the middle of the gantry driving both sides, geared down with a belt at the motor.
I might try a direct driven pinion first, maybe I don't need that power anyways.
Thank you for putting the link, Ger.Quote:
Originally Posted by Scot808
Scott, generally no, we do not sell to the public. Our main focus is OEM sales, but we do sell one-offs rather regularly to OEM customers.
The reason I am here is that I am happy to help DIYers with their own implementations. You would not be happy with the price of how we do it, and the whole concept is rather simple for you to apply.
We unfortunately can’t currently sell bits and pieces, which is what you will end up wanting.
The advantage to use GT2 over T5 is that it's nearly backlash free. You will loose this advantage with a gear again, so I would avoid a gear and try to find a stepper with 0.9 angle per step and high torque and try to use it without gear. An alternative is to use a harmonic drive as gear, which has low/no backlash. Cost is about 150$ used. It depends on what precision and speed you want to achieve. (e.g. high precision, low speed => harmonic drive 1:50).Quote:
Originally Posted by heavyweather
Hey Mike, did I read somewhere that it is necessary to have the belts in some kind of track to keep them from running off even though they are under some tension?
Thanks
Also, how much down pressure is required between the idler rollers and the belt?
Thanks
In answer to your previous question, yes the belt needs to be captured with side walls, flanges on the pulley or idlers do not work. As far as pressure between the idlers on the stack of two belts, no, no pressure. Close to zero clearance is best.Quote:
Originally Posted by tkms002
In my building gantry router cnc machine, 3 axis are through the timing belt drive connections to the ballscrews. No solid solution to the little non-synchronization between gantry drives or backlash are there then. May be the using of glass scale encoder is a solution. But it cannot be implemented in Mach3 environment under servo or stepper motor drive conditions. Presently, no step down gear ratio are used between the timing belt pulleys(Is it better than using small pinion to a large gear in term of backlash amount??). Two 32 teeth are linked with MT5 belt. Wider belt is more preferable in that case as well. Thanks.
Has anybody ever implemented Mike's system by forming the bottom "belt" from epoxy using a real belt as a mold?
I've seen a router where the bottom belt profile was machined into aluminum.
now if I only had a mill with the correct profile cutter. That would be the best way to go I would thinkQuote:
Originally Posted by ger21
I personally think that would not be an improvement. If the lower belt wears enough that you need to change it out that would take 20 minutes. If the aluminum wears out how long will it take to change it out? Especially if you have to mill the aluminum first. T5 belt is so inexpensive it makes no sense to reinvent the wheel! Go with a wider belt if you think you need more ability to handle the force.Quote:
Originally Posted by tkms002
Ha ha ha! First time I check this thread in a long time and this is what I read.Quote:
Originally Posted by tkms002
Yes I did exactly that. Super simple setup, I even made it on a table as a base. I put some tension on the belt and made sidewalls leaving a few mm space. Then poured and it worked really well.
Interesting, I was thinking about doing this last year. Never got to it.Quote:
Originally Posted by svenakela
Which epoxy did you use? I assume you greased or waxed the belt before pouring? Which belt?
Funny, I do not get alerts for this thread or I would have chimed in!
So, with regard to molding the base teeth, I too have done this, and the first discovery was that clearance is needed to allow the very slight pitch changes of the upper belt, from belt to belt. It will mesh with an upper belt over a short distance, or sometimes a long distance, but not reliably, belt run to belt run. Clearance is needed. So, you need to replicate the base belt complete, which adds another step and for a one-off, not worth making a mold.
For me, having base belt sections that are molded would be a good thing, but has not yet become essential. VHB to hold base belting down is great stuff if you use it right.
Either way, when I make a mold, it will be cut metal, and geometrically will make base teeth the same as the belting. Some features, though, like the little groove in the bottom of the groove, aid in getting air out of the mesh, reducing noise, and are a complication that would be solved well by replication..
ding, the more you know..
We put this drive in our KL7 Series CNC routers at BobsCNC. I love the cleverness of this design.
https://youtu.be/GRhJgDyyM7g
Hello, me too, it's ok.Quote:
Originally Posted by ger21