Mod the Machine

Some Time at Shaper HQ

A couple of weeks ago I was able to spend some time at the headquarters of Shaper Tools to have a little time with their new Shaper Origin tool and work with them on building a better integration with Fusion 360.

 

If you’re interested in woodworking and haven’t seen or heard of the new Shaper Origin router you need go check out their website. I think the best link to fully understand what it is and how it works is the “Features” link where there are a series of videos demonstrating various features of the tool. My definition of the tool is that it’s a cross between a hand-held and a CNC router. You upload the design you want to cut onto the router, like you would with a CNC router. The router has vision and uses the domino looking tape you can see in the picture above to accurately know where it is on the board. You visually position your pattern on the board using the screen on the router and then move the router along the pattern by watching a “cursor” on the screen.  The spindle moves independently of the router so as you move the router the best you can to follow the pattern it corrects the position of the cutter to keep it where it should be.

 

I worked primarily with Sam while I was there, (who you’ll meet on the demo videos), and met most of the rest of the team too. They’ve been working on this for a long time and have gone through several prototypes and are working hard to put out a good product. As you can probably tell, I’m excited about the product and can see using it in my shop.

I don’t want to say too much about the Fusion integration at this point because it’s still a work in progress and I don’t know where we’ll end up but it should make creating the patterns to cut much easier than without it.

-Brian

CNC Fun

This past June for the Forge Developer Conference I worked with some of the great folks at opendesk and ShopBot to put together a working demonstration using their furniture designs, machine tools, and Fusion 360.

opendesk has a large catalog of furniture designs that are made locally on-demand from sheet stock. You should check out their website because it’s an interesting concept.  ShopBot has a selection of CNC routers in all sizes from large 12 by 5 foot monsters down to the portable Handibot.  We decided to use the Johann Stool design from opendesk and allow attendees at the conference to design custom engravings for the top of the stool that would be cut at the conference using a ShopBot tool. 

I got involved to try and create a simple interface to allow non Fusion 360 users to easily create a design and send it to the router.  This consisted of two parts.  First I created a series of Fusion 360 custom commands that draw various designs as a sketch.  The picture below shows the new panel that the add-in creates in Fusion and its commands.  There are several different patterns that the commands allow you to create.  The one shown below creates a rectangular mesh with the grid positions randomized.  There’s also a command that creates several polygons to create a flower pattern, one that creates circles in a random pattern, one that rectangles arranges randomly, and finally one that draws sin curves. 

 

The main thing to remember with all of these specialized commands is that they’re just automating the creation of sketch geometry.  Below is the result of using the custom sketch commands and a bit of manual editing on the resulting sketches to create a new design.

The last custom command provided by the add-in sends the design to the CNC router.  To make the entire process easier, it doesn’t use the NC capabilities of Fusion 360 but with a single button click it directly creates the g-code data from the sketch geometry and sends it to the CNC router.  The command gets the geometry information from the sketch and essentially treats the sketch geometry as the tool path to create a g-code file that will drive the cutter along the sketch geometry.  Splines and circles are stroked into small lines and text is also converted into lines so the g-code consists entirely of point-to-point directions. Below is an example of one of the stool seats that contains some text.  To reduce the time at the conference to create a stool the stools were already mostly cut out in panels of birch plywood and then only the custom pattern on top needed to be machined.

 

Here’s Bill from ShopBot at the booth cutting a stool top. Bill also reported on the experience in his blog.

 

Besides doing the stools, ShopBot also brought a couple of the portable Handibot CNC routers and we used the same process to machine small badges that people could design in the same way. If you haven’t seen the Handibot before you should check out the website and look at some videos on YouTube to see what people are doing with it.

 

The whole process of getting ready for the Forge conference was a lot of fun and very educational for me.  CNC isn’t new to me but I hadn’t every directly written g-code before.  The entire Fusion stool add-in is currently available on github.  This could easily be done with Inventor too but so far I’ve only needed it for some Fusion 360 events.

After the Forge conference, a couple of guys from Autodesk (Philippe and Lucas) wanted to do something interesting with a Handibot at another event.  They liked what we had done at the Forge conference and had the great idea of cutting chocolate. Philippe is a much more colorful writer than me and has written a report about their adventure with chocolate.

-Brian

Bathroom Vanity

I previously made a post about a some VBA code I had written to help layout the boards from a woodworking project so I could create cut sheets.  I just looked up that post and couldn’t believe it was almost five years ago. 

In that post I had an image of a bathroom vanity that I had started to design and used as the example.  I did complete the design in Inventor and finally finished building it a few months ago.  Here are some images of the final project.  Having the CAD model helped a lot in laying out the curved legs and matching the curves on the door and drawer fronts.  I didn’t do anything in Inventor for the handles but sketched them out and hand carved them.  These pictures aren’t the greatest, but I’m happy with how it turned out.

Woodworking – Board Layout

Ever since my initial post discussing the use of Inventor for woodworking I’ve been planning on writing a tool to help laying out the individual parts onto stock so you know how to cut them out.  I’ve a design in mind for an add-in that would have some nice features for this but unfortunately haven’t been able to get going beyond some initial design.  That’s the problem with making the project too big to begin with.

Right now I’m in the middle of a new woodworking project at home and could use my non-existent add-in to layout my boards for cutting. Instead of waiting for my add-in that may never show up I decided to do some quick and dirty coding that would do some of the work and should still be a lot better than nothing. It ended up working pretty good, for at least what I used it for. I thought I would go ahead and share it with the rest of you and hopefully you can get some use out of it to.

Here’s my latest project, a vanity for a bathroom that I’m remodeling.  I’ve constructed it completely in Inventor.  That’s the first step, to get a complete and accurate digital prototype.  Here’s a picture of my project rendered with Inventor Studio.

The programs to help with the layout are small VBA macros and are available here.  The link is for a text file that you can copy and paste the contents of into your VBA application project.  The first macro is called LayoutParts.  To use this have your assembly open (in my case the vanity assembly shown above) and run the macro.  After running this macro with my assembly I see the result shown below.  A new assembly was created and every part is layed out flat on the assembly x-y plane.  An assumption made by the program is that when the board parts were created that they lie flat on the x-y plane of the part coordinate system.  It’s beneficial to have each material you’re using colored in an obvious way so you can easily tell the differenced.  The program also constrains the part x-y work plane to the assembly x-y work plane so they can easily be moved around in that plane.

Next, I created a sketch in the assembly that represented my stock boards.  In my case I have some cherry stock that is of various widths.  I drew a sketch that contained all of these boards butted up to each other since I knew I would have to do some glue-ups.  With this sketch I then manually did some nesting by dragging the parts around to see where they would best fit.  While doing this I found I needed some additional capability to rotate the parts and to flip them over.  This resulted in the creation of the three other macros; FlipPart, Rotate90, and Rotate180.  After a few minutes of this manual nesting process I ended up with what’s shown below.

I inserted this assembly into a drawing, added a few overall dimensions to some of the boards, printed out the drawing and then started laying out my project on the actual boards using chalk. I’ll keep this layout drawing handy while I’m doing the glue-up and actual cutting.

I’m still hoping to write the bigger program some day, but these simple macros ended up providing a good share of the capabilities I needed. Hopefully they can help someone else too.  I’ll post a picture of the real vanity once I get it finished.

Woodworking with Inventor

This posting is a little off-topic of the API but I thought I would show you a little of how I use Inventor at home.  I do some woodworking and use Inventor to design my woodworking projects.  I agonize over the design and worry about every cut. Being able to fully design every piece and see how they fit together before making any saw dust is a huge help.  Here are some pictures of my latest project, a Murphy bed.

  
The bed in the up position. (click to see full size in new window)

 

 
The bed in the down position. (click to see full size in new window)

 

 
The real thing. (click to see full size in new window)

Inventor worked great for the initial design.  Where it fell short was in the process of going from that design to a set of working drawings.  The biggest issue was determining the stock I would need and how to cut the pieces from that stock.  Admittedly this is mostly a woodworking specific problem and not something Inventor was designed for.  The method I ended up using was to create an assembly for each type of wood.  For example, I had one assembly for all 3/4" oak plywood, and another for all 3/4" solid oak. In each assembly I have a sketch that contains one or more rectangles that represent the stock.  I inserted each part into the correct assembly and manually positioned them within the stock. Below is a screen shot of one of these assemblies.

Laying out the boards on the stock.

I made drawings of these assemblies to use in the shop. These drawings, an assembly drawing containing the parts list and a few more detail drawings, and I was ready to start cutting.

I plan to write an add-in to help automate the stock layout process. I have the intial design but it will be a long-term project.

I purchased the bed mechanism and plans from Rockler Woodworking. Their overall design is very good and the hardware functions great.  The goal of their plan was to make a bed that works and the construction being as easy as possible. I didn't like some of what they did to make the construction easier so I made some changes. The majority of the wood in their plan is just plywood with iron-on edge banding.  I used solid wood to cover the edges of the sides and made rail and stile panels for the front doors.  I chose baltic birch for the bed frame and left the edges exposed. They also had a lot of screwed butt joints in their design. Instead I used a combination of dovetails, biscuits, and pocket screws so none of the fasteners are visible.