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Very nice case design.
Chris
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I've been absent around CNCzone recently, as I've been hard at work on the version 2.0 prototype. The entire design has been optimized and almost every single part on the machine has had some modifications to it. I got the new machine under power yesterday, and figured it was time to release some images and give a progress report. It still needs final alignment and completion of small details like a door for the electronics and attaching the cover. The machine build went together very smoothly. A few photos are posted below, and here is a short list of some of the changes. Many thanks to everyone in this forum who contributed suggestions and shared details of their own modifications.
- The entire base is built from one thickness of wood (3/4”).
- Right and left sides symmetrical. This will make it easier to enlarge the machine and add a slaved stepper to the left side.
- New cover design. More wood, less plastic, for improved sound containment (& a little cheaper).
- Elimination of the difficult to cut rabbet at the top of the inner skins.
- Fewer sizes of metal stock to order.
- Roll-pins in carriage parts to create rigid moment connections.
- New router mount design, which is easier to construct and uses smaller sizes of stock.
- Router mount drawings for both Ridgid R2401 and Bosch Colt.
- Z axis optimized for better utilization of travel. A full 5 1/4” now available.
- More height under the gantry.
- X axis travel increased by about 3/4”.
- Built in tensioners on both X and Y belts.
- Uses standard belt sizes. 200 and 250 tooth.
The new drawings are 100% complete. I now have about 5000 photos to sort through so I can completely rewrite the assembly instructions. I am aiming to release the new plans in a couple of weeks. I'll be sending out new download links to everyone who has previously purchased the plans.
-Bob
Very nice case design.
Chris
Bob that looks awesome! Looking foward to the new plans. I feel better that I haven't started mine yet!
Well, guess I know what my *second* machine build is going to be!
Thanks for this new update!
I'm only in high school and I will be building this CNC when the designs come out. I've got a whole summer ahead of me. Wish me luck guys!
Same here.Originally Posted by antisubae
Well, guess I know what my *second* machine build is going to be!
Well done Bob! All the changes sound like great improvements ... and that coming from a guy that usually treats "new and improved" as a warning label.
Looking forward to seeing the drawings ...
Cheers
Charlie
I cant wait to receive the 2.0 plans!
"Momus", Greek God of Satire, just wondering about the name in relation to this machine.
Henry David Thoreau references him in Walden. In his first chapter, "Economy", Thoreau notes what he considers the valid objection of Momus/Momos against the house which Minerva/Athena made, that she "had not made it moveable, by which means a bad neighborhood might be avoided". From Wikipedia.
Chris
Thanks for all the positive comments. I can't wait to start using the machine, and unfortunately as soon as I got it under power I went and got on a plane to Texas. Then I got sick. Ugh. Almost recuperated, so back to getting the final touches on the machine tomorrow.
Forgot to mention one other significant change:
- The X motor is relocated from the rear of the machine to the front. Now it is possible to take that motor out without touching any other components. Before it required tearing down half the machine.
-Bob
Funny you should reference the Thoreau quote, that is where I first stumbled across the name, and long before Wikipedia existed. I've also seen Momus described as the god of criticism, or mocking criticism, although I'm far from a classics scholar so I could be totally misinterpreting everything I read. In the real world my job title is unofficially "critic," so I thought it was kind of amusing that I had my very own god to represent me. And being from the architecture world, I liked that it sounded like a cross between MoMA and domus. So the name stuck in my head. Given the content of the original quote, the name would have been perfect for a manufacturer of prefab buildings."Momus", Greek God of Satire, just wondering about the name in relation to this machine.
Henry David Thoreau references him in Walden. In his first chapter, "Economy", Thoreau notes what he considers the valid objection of Momus/Momos against the house which Minerva/Athena made, that she "had not made it moveable, by which means a bad neighborhood might be avoided". From Wikipedia.
As far as how it relates to the machine, there actually is a connection. When I started looking at entry level DIY CNC router designs, there seemed to be a few general approaches:
1. Use large quantities of very low-modulus materials. Use size to overcome the inherent material flexibility. That is kind of like attempting to chase after something running faster than you are. Just never going to get there.
2. Bolt together a bunch of off the shelf, typically mismatched, components (how about 80/20 with linear rails, NEMA 42 motors, and 1/4-20 allthread leadscrews?). Hope for the best.
3. Then there were various John C. K********* type of approaches. I'll refrain from commenting on those.
So it seemed like this segment of the CNC world could use a little mocking criticism to move it forward. Given the potential sophistication of the parts that can be produced with digital manufacturing tools, it amazed me to see some of the contraptions people were building. And I was surprised by the dearth of the most basic engineering principles, designing totally by gut instinct, or by creating a bricolage of pieces left over from remodeling the kitchen. Compare this to other hobby fields where builders learn some pretty sophisticated knowledge to carry out their designs. An example that comes to mind is LoCost car builders, who use FEA while designing frames and suspension components, and then build fixtures to test torsional rigidity of the finished product. Of course having federal regulations that need to be met is a big incentive, but still, have you ever seen anyone do anything as simple as pull on their gantry and measure its deflection with a dial indicator?
None of this is meant in any way as a slam against anyone on this site, or bashing anyone else's designs, by any means. The amount of knowledge contained by the contributors to this site is staggering, and there are some truly beautiful machines. Unfortunately all way out of my build budget. But there seemed to be a problem with synthesis of that knowledge, and it all coming together as a great design that an entry level guy like me, on a tight budget, could build. The amount of knowledge to design a successful machine is almost overwhelming. Lots of factors to balance against each other. I'd consider most of those crude designs I was seeing as (expensive) learning curves, trying to resolve all of those factors. A very noble pursuit, and my own attempts to build a better contraption were quite humbling.
So ultimately I made my little stab at proposing a different course, and hoped I would be providing some criticism through setting a positive example. The plans aimed for a higher level of graphic clarity, and the machine design has its own philosophy: small quantities of high-modulus materials, which keeps everything compact and stiff, and a matched level of (in)accuracy of components throughout. Basically, I was aiming for a more holistic design that met my own particular design goals and needs. Its been far from perfect, as we've seen, and I don't claim it to be the best thing since sliced bread. But hopefully its a good foundation that can be developed further, and maybe my efforts can serve as some sort of small example.
So there is my mocking criticism. Hopefully all taken constructively and in good fun. I, of course, now position myself exposed to be the recipient of the same. All in the name of progress.
-Bob
Well that seems like an accurate summation of the situation and an equally suitable name for the machine...no criticism here.
Chris
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