CNC Tools

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Bay Area Digital Fabrication Club meets this Thursday

The Bay Area Digital Fabrication Club meet-up is meeting this Thursday.

Graciously hosted by BlueSprout, Oakland's new tech factory, the Club is an informal and fun user's group where designers, fabricators, and artsts share tips and tricks about these amazing tools. This month's meeting is all about cheap and/or free 3D modeling options for 3D printing & subtractive fabrication.

Remember, bring something you've made to show & tell, and get a chance to win a prize: $60 worth of 3D printing filament or CNC tooling, your pick!

Would love to see you there!

Reception Desk Photos...

So here's some more pics of the recption desk we finished recently. We're super happy with how it came out! Modeled in Revit, with parts modeled in Blender, and cut via CNC out of sustainably harvested walnut, this was our first big complex job we did via our design process.

We love the red our client choose for the wall behind it, it really makes it pop.

That's the wing, the only part that was modeled in Blender (and cut from solid walnut). The rest was modeled in Revit (and cut from walnut veneer plywood, with the guts just being cheap rough plywood). All the wood in the desk is sustainably harvested. The finish is a nice dark walnut stain with a poly sealer over the top.

We had this hourglass custom-made. Seeing that this lobby design is based upon the Death Jr. game, the client requested an hourglass prop for the table. It's a working hourglass, as in it really takes an hour for the sand to go from the top to the bottom. We had it custom inscribed to say 'To Backbone: Thanks for making my kid look cool. Death' and the other side has their logo on it. Everyone loves it! And I kinda want one for my own desk now.

The client also wanted a classic phone for the desk to go with the overall look. Ebay to the rescue, we found this lovely little bakelite number. It's a great shape and has a really nice action on the wheel. Very satisfying technology, with a nice and heavy receiver and cloth cord.

Y'all will see a lot more photos of this lobby soon, for we'll be finishing up the rest of the job here shortly! There's a logo to go on the wall (that's 80% done) and a display wall we'll be putting up soon. Our first 'big job'! So excited...

Maker Faire!

Wooo the Maker Faire is a ton of fun! Lots of great stuff here. We're also right next to Mr. Jalopy, our favorite blogger and a really funny guy. We made him this sign so that he wouldn't hate us from all the noise we're making with the Shopbot.
    So the PRTalpha benchtop Shopbot was kind enough to send out here for us to use at the show rocks. It's faster than the one we've got at home, and for someone that just wanted to make small stuff, like guitar bodies or signs or something it would be perfect. It's working quite well (once a fuse that worked loose in the shipping was found and set back into place!) and it's quite a draw. Several folks seem to be having the same little ephiany that we did when we first learned about them. You can see the gears turning in their heads, thinking of all the things they could make with one. Gotta say, Shopbot is really good at making accessible and affordable CNC gear for everyday folks.
    The difference between the one we have at home and this one we've got at the show is that this one is an 'PRTalpha' while ours is just a 'PRT'. What this means is that the one at home is always running 'open loop' while the one here at the show can switch from 'open' to 'closed' loop on the fly when it needs to. 'Open loop' is where the computer tells the motors to move the bit a certain distance, but doesn't check that it actually moved that distance. It just trusts that it did. This means when you're doing something that's really complex, or need something to be really accurate, or cutting something really thick, you need to slow it down a bit, for otherwise it can 'loose steps', i.e. not really move as far as it thinks it did and get off register. With the Alpha, it can also run in 'closed loop' where not only does the brain tell the bit to move, it then checks to make certain it did move the right amount when it's done. This means that you don't have to worry about loosing steps when doing stuff. However, it's slower to run closed loop all the time, so the alpha switches between the two automatically depending on what you're doing. So in the end, it runs fast, yet is unlikely to loose steps. Pretty cool. Best thing is that the PRT and the PRTalpha are only different in the stepper motors that drive it and the brain, so at some point in the future when we've got the money we can 'step up' and not lose steps anymore by just swapping out those items.

Design -> Revit -> Blender -> CNC -> real life!

Here's a sneek peak at a big job we're in the middle of. We're doing a lobby for a local game design company, and we're very excited about it. The overall theme of this lobby is based upon an orginal creative work (a fun PSP game and a neat comic) of this company called 'Death Jr'. It's theme is that you are Death's kid and you've got to save your dad (who's in trouble because of something you did). We loved this image of Death's desk in his study from the comic:

So we proposed to base the reception desk design off of it. We were very excited that the client liked the idea, and we designed and modeled the desk in Revit:

Which formed the majority of the desk. However, we wanted to do some very custom parts for the desk. We mocked up these wings for the front in Revit, but we wanted them to look more carved instead of flat. So I exported the wing from Revit into Blender, and then remodeled it until we liked the look:

And then we exported that model from Blender to the CNC toolpathing software, and then carved it out from a solid chunk of walnut we got from Pals down the street (certified sustainably harvested, Pals rocks). Those extra bits in the model are to save some of the wood, so we're not carving it all away:

Then we sanded and finished the wing. We're very happy in how they came out:

They were a nice touch to the overall desk.

We'll be posting a lot more photos of this when we're done, but here's a sneak peak of what it looks like now:

Revit -> CNC -> Product!

So here, finally, is the process I've been going through to produce products using the CNC table in combo with Revit. Been meaning to post this for a while now.

So, we just made a nice kitchen island for a client of our own custom design:

And we needed to make some matching stools. So we did some sketches, some modeling, and arrived at something we all liked. That simple Revit model was then carried forward into a fabrication model in Revit, and the parts from it copied out into 3D space to 'explode' the model:

Then I exported elevation views of those parts to DXF. Revit's 2D views of the 3D model are dead-on, which allows me this very fast and cheap way to generate these clean loops. I then take those profiles and lay them out within the CNC toolpathing software to fit onto a single 4' x 8' sheet of "ApplePly" (a finish-grade maple plywood that's made up of solid fine layers):

Then we feed the CNC table a sheet of ApplePly, and tell it to cut away:

Then we sand and finish the parts:

Then we assemble the parts:

Then we get the finished product!

So, this is making things simply out of '2D' parts, or flat parts cut from a flat sheet. Next up, we'll try to make some '3D' parts, where the CNC table will be carving out reliefs for a possible upcoming large job. I'll post that process too when we run through it. But here's a very fast, cheap, and easy way to go from Revit to reality.

In the future, we're hoping to scale this beyond just furniture and products, and make key parts of a building this way. For example, a nice railing detail for a residential deck could be modeled in Revit, and then broken down into it's parts, which would then be produced via the CNC table for mass customization on the dirt-cheap. We could make a railing where each part was custom for the price of the material and modeling time.

Now we just got to find someone willing to hire us to help them with their house. ..

Big news about the MAKE Show...

So some big fun news to share! We entered into the upcoming "Maker's faire" that Make Magazine is putting on, for we love Make Magazine and figured since it's local, why not try to see if we could get into the show? We're going anyways, we might as well go and show some people some stuff too. So, amazingly, we got picked! We're going to have a table there, and show off stuff we've made, how we make it, and talk all about CNC tools for everyday folks like us.

...but it gets better! Jillian somehow got the Shopbot folks to actually send us a mini-Frank. Apparently Shopbot loves Make Magazine too, and just bought some ad space in the next issue, but wasn't going to be able to send someone to the show. But when Jillian talked to them, and told them we were going to talk about their CNC routers, they decided to ship us out a "tabletop" model Shopbot for the show. We'll put it together there, and then make stuff for folks right on the spot! How cool is that? It will be tons of fun showing people how great these robots are, meeting lots of other folks into making things, making things right there for people, and maybe even selling a lapdesk or bookshelf or something (or two).

This "tabletop" model is about a third the size of ours, and instead of the whole top moving back and forth like ours, this one moves the table back and forth as one of the axises. When Jillian asked Shopbot if this one is any, well, quieter than ours, their response was a "ha ha ha... No."

Now, while we'll be in the 'workshop' part of the show, where other people will also be making things and showing tools off and such, still... between the dust and the noise, let's just say that we're not going to be making any friends within our immediate area... But if you want to drop by, I'll be posting more info as it approaches and we've got a better idea as to where we'll be. Tickets are $12 too, so you should go, for it looks like it will be a ton of fun...

Frank's new Bucket...

Hey! Lots of updates and news, but to start: Frank got a new Bucket. bucket! Those yellow arrows show the airflow's path from the cutter into the dust collector. We were having big problems with the dust collection system clogging right at the end of the hose (that last 3rd arrow). Big chips and 'threads' from the cutting were all jamming up the screen at the entry for the blower, and cutting off any suction. So now we spliced in a bucket into the line, with a screen at it's exit (and a brick in it's bottom to keep it stable) so any big bits would (hopefully) fall into the bucket and stay there, and the lighter dust would continue on into the big white bag on the dust collector itself. So far, so good, except that the bucket does fill up fast, and crawling under there to get it isn't fun...

Frank's new tricks

Finally got the time to work on setting up the CNC table more today. Behold the mighty silver tube of dusting!
The silver tube!
That tube hooks to a big ol' blower under the table where all the dust (hopefully) winds up. On the other end it's hooked to a skirt that surrounds the cutting bit:
the dust skirt
It's like the opposite of a hovercraft! Anyways, see that gap there? Between the bottom of the router (the gray tube thing) and the top of the dust skirt? That gap's gonna cost me $250 to fix. My router is too small and we have to get a bigger one. Which we needed anyways, really, so it's not too bad. Only bad thing is that no one locally has it except for one place that wants $100 more for it than Amazon does, so that means we'll still have to wait a bit before we're 100% operational while Amazon ships it to us. However, another new thing we got set up is the Z-Zero plate:
z-zero plate
Now, this is pretty cool: when that magic plate of aluminum and that jumper-cable-looking clamp touch, it sends a signal back to the table's brain. So you place the plate on top of your material, clamp the clamp onto whatever bit you're using, and then tell it to find the plate. The table then lowers the router until the tip of the bit and the plate just touch, and then it does it again at a quarter of the speed to be sure. Then the brain subtracts the thickness of the magic plate and now knows exactly where the top of the material you want to cut is (or where the top of the table is, so it doesn't cut too deep, if that's what your after). Huge time saver, otherwise you have to set it yourself, and it changes every time you change a bit, so you have to do it every time.
But with the dust collection and Z-zero in place, we can now do this:
spiral cut
The Shopbot comes with software that allows it to take a bitmap image and convert it into a 3D cutting file. So I whipped up this in Photoshop:
spiral cut graphic
and turned it into this:

pretty neat, huh? Here I set the white to be the top, the black to be 1/2" deep, and it figures out the rest. Semi-automatic relief cutting! I'm going to do a lot of this I feel, using mathematically derived patterns for decoration, surfacing, and the like. Now, this one is a little rough due to the fact that I can only use long, flat-ended cutting bits with my table because my router is too small. Normally you'd use a bit with a tiny, 1/8"th or 1/16"th ball end to get smoother cutting and a finer detail. So as soon as the new router shows up, I'll be able to show you all a nicer example.

Frank's first day out

Sorry for the long break in the 'blog. Had a whole mess of work getting my handouts ready for Autodesk University for the two classes I'm teaching, and then right after that I had to get a portfolio together to go talk to some folks about some possible work (on top of 20+ hours a week consulting). Now I should be able to get back to my once-a-week posting. Anyways, super excited to say that I finally got the CNC table working!
Frank's first sign
After some software problems (that were totally of my own dunderheaded creation) got sorted out everything is working great. Except that the dust collection system is on back-order, so we can't do too much just yet. But I had an meeting this afternoon with a client who wanted to see a portfolio of stuff I've done, and I figured this morning why not make something to carry the portfolio in to show off the new CNC-goodness?
And here's a somewhat blurry photo of the final result. It's two bits cut from a sheet of oak plywood held apart by bolts.
Bolt detail
The presentation boards then sit in there, held on the sides by the top bolts and held up by the bottom ones.

So then the boards just sit in there, and you can pull out whichever one you want. Then that big top slot acts as a handle as well.

So you can haul it around. It's funny, it took longer to draw and design on the computer than it did to cut it out, sand it, and stain it. I'm not too happy with the finish, I only had time for one coat. I think I should hit it with another, and then maybe give it a satin poly finish.
Front shot
Finally, I really wanted to do something more subtractive and/or sculptural to that blank front. But without the dust collection system, I'm loath to do something that would create yet more dust. But, lucky for me, it just showed up from UPS while I was posting this, so very soon you should see some more complex work, and we'll also have the big ol' Robot christening party...

Revit -> Shopbot, Conversions & Diversions

OK, with the Shopbot on the way, I've been working on how we are going to get models out of Revit and produced with the Shopbot.
The issue here is that the Shopbot isn't a 3D printer, it's more a 3D remover. While the software it comes with is great for cutting out parts from a flat sheet, or taking a bitmap image and producing a carved relief from it, it doesn't have anything for freeform complex 3D models. So while it's going to be great for carving out lots of stuff we have ideas for, I'd like to someday scale this whole CNC process up to making whole Buildings, or at the very least lots of parts that go into the Building... and to do that, I'll need to be able to take a complex 3D model out of Revit and have the shopbot generate it...
Here's an example part I quickly made in Revit by combining a solid blend and a void blend:

See, there are two parts in this, first off I need a way to produce the 'Toolpaths' that will direct the moves of the shopbot so that it carves this complex shape. To do that I'm looking at a bit of software that's called Millwizard, because it can output directly to a format that the Shopbot can use. Here's a image of this part, exported from Revit as a solid and then converted into a 3DS file, with some example toolpaths:

That red 'fuzz' of lines represent the passes that the router will have to take in order to carve out this shape. I left out the 'rough-in' cutting, where the part is initial quickly whittled down into a rough shape just for legibility (it would be too many lines, you wouldn't be able to see it).
This software not only figures out the toolpaths based upon the router bit you're using and the router/tool speed, but it will also figure out the 'layers' you'll need to stack if you're trying to make something that's thicker than you've got the ability to make.
For example, the Shopbot we ordered can only move up to 6" in the Z-axis, so if we wanted to make something very sculptural that's thicker than that, we'd have to do it in 6" layers. This software will figure that kinda stuff out for us. We'd also have to flip it over to be carved from the other side too, for the Shopbot is only a 3-axis machine, but we'll figure that out when we start working with it (I hope).
This is just a rough pass of testing, obviously that 3DS file could be better subdivided to be smoother...
But the general idea here is that Revit Families could be generated that make up pre-fab parts of a house, that house could be quickly designed and modeled, and then the parts that were used (in all their variations and sizes) could be exported out individually and either carved directly via the Shopbot or have molds generated via the Shopbot that then are used to cast the desired parts, and the house goes together like one big puzzle...
But first, baby steps, gotta clean out the shop, wire up an outlet, make some simple products to sell and/or consulting side jobs to fund the bigger dream...


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