OrigamiWaterLab / OWL300

The best small water treatment plant ever built.
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Get a CNC Router #1

Closed eak24 closed 6 years ago

eak24 commented 6 years ago

We need a CNC router. I chose the Maslow. Relevant conversation is here: I did some preliminary searching and I found the Maslow CNC. You have to do some mental re-adjusting of your definition of a CNC. Accuracy is down to 1/64", max ipm is 35, and max cut depth is 1/8"-1/4". The two big advantages of this is the $350 price tag, and the fact that it is vertical, and consequently takes up comparatively little space.

Heya Pops,

To get you up to speed, I'm planning to get a 4' x 4' CNC router. But I don't want it to be that large of a footprint. Will and I are considering options. Look at some videos on the Maslow CNC to start getting excited. It has a 4' x 8' work area, and is expandable/shrinkable.

The alternative is to get a more traditional CNC router for around 3k-10k depending on the quality.

(Conversation between Will and Ethan):

Whats the weight of a 4x4 PVC sheet?

0.75" is about 120 cm 120 cm 7.5 cm 1.38 g/cm3 0.001 kg/g = 149.04 kg = 328.6 lbs

.750 thick right?

Yes. But most likely I will just be using 0.25" PVC

That will play into the overall rigidity of the table design. The rigidity of the spindle setup will depend on max DOC and feed rates as well as precision more than accuracy. From some quick searching yesterday more traditional cnc routers are accurate around .001-.0005 and precise ~ .005

That is much more accurate than I need for this project.

What features are you looking to machine? Contours, small holes (under 1") or milling large dia. holes ( over 1")?

Contours, small holes. But couldn't I cut large diameter holes with a router bit?

The Maslow is a cool setup, and with minimal investment I think its worth trying depending on what you want to do. I don't like the fact that it relies on gravity and the weight of the tool. Tool deflection would be a concern due to the gravity/chain drive system.

I was concerned about this as well. This video of the inventor talking about design choices is excellent and explains that in this system, where we're taking shallow passes on relatively soft materials, the force required is minimal and the shaft deflection is next to nothing. But remember - this isn't for super high precision, so I'm speaking relative to the expectations for such a system.

Chip evacuation is another area of concern, might be ok depending on how far the Z axis travel is. Not sure how the Z axis works will do some more research on it this weekend. Not sure about the repeat ability either, this design looks fine for cutting patterns but if you wanted to locate features at specific points on multiple sheets that may be an issue. So if you wanted to have 5 different sheets with the same hole patterns I'm not sure how well this would work. If you want to cut various parts out of a sheet rather than the sheet is the part, it might be fine.

The edge-to-feature required precision for my application is not demanding.. I'd be happy even if it was a 1/4" off, although I'd prefer less than 1/8"

Could try it, worst case would be you have a semi portable wood pattern cutting machine only.

Just bought it. Should be there in late February. I agree, I think the initial investment is to low to not buy - even given the risk this thing might not work...

Will keep doing some research. Do you have a model of what your looking to make? Do you want something purpose built or something that offers flexibility as to what types of materials and operations can be done?

I don't have a model except for in my head at the moment. I did finish a model of the CryptoCase. See here for that.

My thinking for now: get the Maslow up and running. If I find there are some jobs it can't perform that I need, I should look into a more traditional CNC - perhaps a smaller format because the Maslow could do a rough job with the larger things.

How does that sound?

Next step: design a hanging system so the Maslow can fold up into the ceiling and then build it with the Maslow itself.

I'll share you on the Fusion project I'm using to develop the little plant.