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Whosa whatsis
Polymathic autodidact
Polymathic autodidact


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Put together a little article with +Whosa whatsis about one of our pet peeves: how to define 3d printing "resolution." Check it out at the link:


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My first class with +Whosa whatsis on has just been released, "Additive Manufacturing: Optimizing 3D Prints." classes are behind a paywall, but they have free trials! Many schools also have subscriptions.

The class on

Some of it is also available via LinkedInLearning:

Check it out!

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Just adding the finishing touches to Hackaday Prize 2017 project with +Whosa whatsis, "Hacker Calculus" - teaching calculus intuition hands-on, with little or no algebra. Project video is up:
The overall project is at - please check it out.

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Anyone at SIGGRAPH? Organizing a Birds of a Feather session with +Whosa whatsis about best practices for making 3D printed math and science models. Tuesday 8/1 10-11:30 AM, room 506 in the Convention Center. Bring a cool print!

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We have a 3D printing meetup at the Supplyframe Design Lab at 6PM. If you're in the Pasadena area, come check it out!

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Citing precedent going back to the 1600s, the justices agreed with Impression Products that as soon as a product was in the hands of consumers, patent protection was finished. “Once sold, the Return Program cartridges passed outside of the patent monopoly,” the unanimous court decision, “and whatever rights Lexmark retained are a matter of the contracts with its purchasers, not the patent law.” Lexmark can still try to enforce its agreements with individual customers who don’t return the empties as promised, but the agreements don’t apply to third parties.

IANAL, but this sounds to me like this opens the door to, for example, third-party aftermarket upgrades to add a heated build chamber (deformable insulators and all) as long as the customer installs the upgrade rather than either company.

Has anyone done any experiments with using a remote air pump instead of a downward cooling fan mounted to the toolhead yet? I'm thinking something like an aquarium air pump or a small vacuum pump with tubes going to the toolhead.

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Excited that our new book (#6 in collaboration with +Whosa whatsis) is now out. If you want some fun stuff to do this summer with your 3D printer, how about a few gravity wave models? Publisher's link below, but also available on Amazon and other big booksellers.

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Anyone actually use toothed idler pulleys like these? They seem to have a huge design flaw: the OD of the bearings is the same size as an m3 washer and will rub against it. Do you need special conical washers for these?

I'll have to count up screws and stuff before I can make a proper BOM for the Cranestyle Mini, but here are some links to get you started:

* 1x NEMA14 TR5*2 linear stepper (note: Robotdigg motors are wired 1324 and come with cables that cross-over the 2 and 3 wires, but if you want to do any nicer wiring, you'll need to know that):*2-Acme-Leadscrew
* 3x high-torque NEMA14 (these unfortunately don't have D shafts, post if you find a good source that does):
Alternative, you might try these instead, they're more expensive (shipping is also insane, IIRC), and you'll need a supply voltage of at least 24v for them to be viable, but they do have a D shaft (also, wires are integrated, which I don't like):
* 3x Pololu Stamped Aluminum L-Bracket for NEMA 14 Stepper Motors (these could be replaced with RP parts, but they are good for rigidity and heat sinking purposes):
* 1x MGN9C and 2x MGN12C, all 150mm long. Robotdigg has the MGN9, but only has MGN12 in longer lengths (which I suppose you could cut down if you really wanted). Both can also be found on both Amazon and Aliexpress.
* 1x each of Misumi HFS5-2040-220 (this one is actually a bit long, and I might revise it to 210mm) and HFS5-2080-150. While you're ordering there, you might as well get one pack each of M3 and M5 T-nuts.
* 2x Gates GT 2MR196 belts, 6mm width (closed loop, 196-tooth, the current version will not work with cut belts, but this will probably change)
* 2x 16T GT2 pulleys
* 1x CR8 hot end (1.75mm version, and you will also need thermal grease/heatsink compound to assemble it, and a 30mm fan, or the X carriage can be modified to fit a different hot end):,searchweb201602_4_10152_10065_10151_10130_10068_10136_10157_10137_10060_10138_10155_10062_10156_437_10154_5010020_10056_10055_10054_10059_303_100030_100031_10099_100029_10103_100028_10102_10096_10147_10052_10053_10050_10107_10142_10051_10084_10083_5190020_10080_10082_10081_10178_10110_519_10111_10112_10113_10114_10037_10183_10182_10185_10032_10078_10079_10077_10073_10123_142-10050,searchweb201603_2,ppcSwitch_7&btsid=1a8d0bc3-cb90-460b-9748-141a36548a1c&algo_expid=ff0c2010-8ff9-4c06-8d2f-b684b9b732da-0&algo_pvid=ff0c2010-8ff9-4c06-8d2f-b684b9b732da
* 6x F623 bearings for smooth-side belt pulleys PLUS an additional 8x for toothed-side pulleys OR substitute 4x 16T pulleys with bearings for an m3 shaft (not yet tested):
* 1x v623 bearing used for extruder idler (or it can be modified to use a regular bearing, extruder design may also not be final):
* 1x Tatsu Mini drive gear (extruder can be modified to use a different gear):
* 1x E3D embedded bowden coupling (also check US resellers):
* 1x Openbuilds 100mm platform heater (I actually used the older version, but this one should be better):

There are also plenty of nuts and bolts that I'll have to measure and count, but that should get you started.
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