Grbl Controller supports the AlaMode in version 3.3.8

I’ve fixed a problem with Grbl Controller where it expected Grbl to reset upon serial port open – some devices like the AlaMode initialize once and when you connect, there is no version response. The fix involved sending a Ctrl-X if no response was detected.

The AlaMode is an Arduino-compatible board that stacks on top of the Raspberry Pi and communicates serially through the GPIO bus.

Checkout my writeup on getting the AlaMode running with Grbl

You can pick one up at MakerShed

Shapeoko modified with belts on the outside

I’ve managed to upgrade my Shapeoko with belts on the outside. This gives me more working width and also moves the belts further away from debris. I ran a test and it works really well. I need to add a clamp down system, the pressure clamp approach mostly works but I have had one problem with it when a cutout piece moved while I had stepped away and popped the Lexan piece up in the air. Otherwise, the milling performance has been excellent so far into hard plastics (no problem with HDPE).

For the belt mountings, I used steel used for home construction (“Strong Tie”) and cut it into four pieces, then drilled it using measured templates. I did have to use longer 5 mm bolts because of the extra thickness of the plates.

It will make my limit switch mounting trickier, as my limit switch mounting holes were used to mount the steppers on the outside.

I am using thick Lexan for my stepper mounts and it works really well. The four holes in the corners are tapped for 5 mm bolts.

I reused the old Dremel mounting spacers for the stepper spacing mounts and also used extra parts that came with my second Y stepper kit from Inventables to complete the mounting.

All metal from the original Shapeoko kit is unaltered – nothing has been drillled, everything is either stock or has been bolted on (except for a couple of bolts I cut to shorten them).

stepper-mount zip file containing nc and cb files.

Grbl Controller 3.3.5 Released with optimal Grbl detect upon COM port open

Due to a problem a user was experiencing with connecting to non-Uno arduinos, I have modified the Grbl version detect code to no longer send out a linefeed upon connect. Now the code just waits for a response from Grbl upon connection.

Since my last posting on Grbl Controller, I have also made some modifications to the visualizer – it now handles pretty much any kind of valid gcode.

Also, when sending a file, you can now choose to send each line as-is or have Grbl Controller filter it based on what is supported on Grbl 0.8. This setting is in the options dialog.

Replacement bed for Shapeoko

I finally decided to pull out the big tools and make a new bed for my Shapeoko. This build is inspired by this project:

I glued two scrap pieces of 1/2″ MDF board together and then routered clamping channels.

The clamp material is solid 3/8″ aluminum rod cut to about 1 1/2″, drilled and tapped for 1/4″ bolts.

To see how well it worked with the DW660, I decided to try milling a scrap piece of 8mm Lexan I pulled from some equipment to make two stepper mounts for my next modification: the outside belts.

This time I’m getting proper “snow”. When I tried this with the slower Dremel I was getting hot flakes permanently adhering to everything on the machine. This time, no adhesion!

I was using a two-flute bit. Probably should have used my 4 flute instead as the final result wasn’t as good as I had hoped. Still not bad. Job run time was about 30 minutes. Could have be 20 minutes if I hadn’t decided to do the full mill on the two big circles and instead chosen a simple cutout approach.

Shapeoko now has the powerful Dewalt DW660 trim router as a spindle

I ordered the DW660 from Amazon and designed some brackets in CamBam, then milled them using my Dremel spindle. I’ve mounted the new spindle and have tried it with HDPE (cutting board). Works exceptionally well – no slowdown at normal speeds – speeds that would slow down the Dremel at least by half its RPM.

Check out my posting on the Shapeoko which includes gcode files for the brackets:

I’m currently working getting a proper clamp-down system on the bed. Additionally, I’m working on a light sensor-based limit switch using milled holders. Hope to get that build report up on the web site soon.

Shapeoko reconfigured with dual Y drives

I’ve managed to get my Shapeoko working with dual Y servos – why? I was getting tired of the undriven side sloshing around whenever I tried to work harder material. I ordered the extra drive kit from Inventables – it came with some extra hardware that I didn’t need and was missing a part (which i found a substitute for in my parts bin), but overall happy with the purchase.

Since the stepper they provided was not matched to the ones I ordered (I had purchased the mechanical kit only and sourced my own steppers), I repositioned the existing stepper and made the new one the Z-axis. Only issue is that the voltage setting on the Pololu driver isn’t right – the stepper runs a little warmer than I’d like. I need to tweak the pot slightly to bring down the current.

Check out the swapped red/blue wires on the A axis (upper right) so the stepper runs in reverse.

Hoping to do a more extensive writeup of the transformation.

Side note: I tried to run the 6×6 inch calibration pattern (, but it doesn’t fit into my Shapeoko’s working area – it is about 1/4 inch too small. Will need to edit the original design and try again.

Using Amazon S3 and getting logs

I’ve been using S3 to host my Grbl Controller downloads. So far I like it.

I just started using S3 Browser (free for non-commerical) and am liking it. It appears to be Windows-only, though.

I use it to upload binaries and download logs. After I download the logs, I delete them on the server so I can keep track of what I have already downloaded. Funny thing is I can’t find any good log processing tools that don’t require lots of manual setup. There is one online tool that looks good, but it is $5 a month, not worth it for the kind of use pattern I have.

Simple solution: Download notepad++ and do a search through the logs using regular expression. Go to Search > Find in Files and I use this expression to find all executable downloads (Mac or PC): GrblController3\d+

There will be duplicate entries, but you can usually deduce easily that from the log info.

Works well enough to tell me that I’m getting about 1-4 downloads a day, about 80% Windows, 20% Mac.

Minor fixes to Grbl Controller 3.3.1 Visualizer

I’ve posted a new Windows build of 3.1.1 on the S3 site. A user found a problem with computer-generated gcode that is conforming but Grbl Controller did not handle correctly in the Visualizer – i.e. it would not process spaces between an axis and value, so g0 x 0 y 0 wouldn’t work, but g0 x0 y0 would. This is now fixed.

Two other fixes made: Last line was being dropped in a file and stray spaces in an empty line would crash Grbl Controller.