Category: General News

Over the one and a half years that the Mill One has been out in the wild, it has accomplished its role as a simple, affordable desktop CNC machine perfect for hobbyists and makers to dive into the world of CNC milling. We’ve designed a new machine (codename LongBoi) that holds that same focus, but as a new platform to allow for processing of larger materials.

It’s exciting to finally have this new machine out in the world for testing, especially since we’ve been working on the design on and off for the last couple of months. Here are our goals with the new machine:

• Simplicity: The LongBoi holds the same philosophy as the Mill One to be a mechanical simple machine by reusing design cues throughout the machine, such as utilizing the angle aluminum v wheel design found on the Mill One and using a limited variety of parts.
• Rigidity: The LongBoi has a 3×3 inch aluminum rail along the X axis, as well as a supported 2×2″ Y axis rail. The Z axis utilizes 12mm linear guides, allowing the Z axis to be rigid and extremely low profile. All gantries are made from 1/4″ steel or aluminum
• Precision: Unlike some of the other larger, hobby grade desktop CNC routers like the X-Carve and Shapeoko, the LongBoi uses leadscrews on all axis, which means higher precision and no belt stretch.
• Openness: The design of the LongBoi allows for a variety of modifications, especially with the simple design and use of 3D printed components. The Longboi uses standard and off the shelf parts that can be easily interchanged or replaced.

We currently have two sizes being beta tested, a machine with a 1ft x 1ft work area and a 2ft x 2ft work area. Want to be a beta tester as well? Check out this form to learn more and apply to be a beta tester! https://goo.gl/forms/Rei7ghZIDg6tlMhl2

A fun way to try new things on the Mill One is to try out new end mills and other hardware. That’s why we created the Mystery Pack! Sign up for the Mystery Pack and we’ll send you an assortment of cool stuff every month.

Are you interested in getting your hands on this Mystery Pack for free? Share your projects with us and we’ll send it to you completely free of charge. To sign up for free Mystery Packs, go to https://goo.gl/forms/ObkEJPFXMklOTBwB3 to sign up and for more details.

We’ve released a new firmware update for the Mill One. This update will work with all Mill Ones. Download it here:

https://sienci-upgrade3.cospark.io/wp-content/uploads/2018/07/GRBL-1.1g-Sienci-Mill-One.zip

This firmware update increases the speed and acceleration settings of the Mill One. GRBL v1.1g has general improvements and bug fixes that improve reliability and performance.

Things to know about this update (please read this carefully if you are updating your Mill One since there are some specific instructions):

• This firmware update takes the Mill One from running GRBL v1.1e to v1.1g. You can learn more about the development of GRBL on the GRBL Github.
• You can update your firmware the same way as you uploaded it the first time. Instructions can be found on our Resources pages.
• Before you start, make sure to clear your EEPROM. EEPROM is where the Arduino stores all of the GRBL settings. Some settings from GRBL v1.1e may persist if you do not clear the EEPROM. An Arduino program in the downloaded firmware folder can be uploaded to the Arduino to clear the EEPROM.
• If you have installed a library into Arduino for an older version of the firmware, you will have to delete it and replace it with the new version. You can find the old libraries in the “Arduino” folder, which can usually be found in the “Documents” directory. Go to the “Libraries” folder and delete the “grbl” folder. This will delete the library and will let you install a new ZIP library.
• Installing this update will undo and delete all your old settings. If you made any changes to the firmware, make sure to save all your settings. You can look at your settings by sending the command “$$”. If you need to make changes to your settings after the update, you can refer to the GRBL Configuration wiki.
• If you run into issues with the firmware, please let us know.

If you want to revert back to GRBL v1.1e, you can download the firmware here.

Over the last couple days, we have been testing the performance of the black HDPE frames. We’ve gotten a lot of interest in a plastic-based frame over MDF. However, we have found several issues with making the frames out of HDPE that leads us to believe that it is not a good option for our customers and we will not move forward with manufacturing them. If you want to learn why and our impressions of using this material to make the frames, please continue to read.

Stiffness

One of the biggest disadvantages of using HDPE is the fact that it is not as stiff as MDF. This makes the machine less rigid. Initially, we believed that this would be negligible, especially based on our previous experience using the material. However, when we assembled a prototype, we found that the reduced rigidity in the HDPE introduced decreased performance and reduced quality in milled test parts.

One of our tests was to make aluminum bitcoin tokens. On the bottom is the test piece milled on the HDPE frame machine. The one on the top is made on a machine with an MDF frame. You can immediately see that there is a clear difference in the finish between them. Both were made using the same gcode, with 1000mm/min feedrate at 0.35mm stepdown using an 1/8″ bit.

Both samples (above)

Sample milled on HDPE frame machine (below)

Sample milled on MDF frame machine (below)

We noticed far more chatter and experienced a more difficult time milling with the HDPE machine. This is also reflected in the milled part quality.

Warp

When we received the parts for the frame from our manufacturer, we noticed substantial warp in the material. We decided to go forward with testing since we believed that some of the warp would be taken up when the machine was assembled. The warp would be pulled straight by the brackets and rails. For the most part, this did occur, but the fit with the acrylic shield was still subpar. There was a sizable gap with the groove for the shield.

In the future, we would need to look into a more dimensionally stable material or have the material stress relieved to prevent warping. This introduces more cost and perhaps would make this upgrade uneconomical.

Conclusion

Although HDPE looks nice and has great water resistance, due to its lack of stiffness compared to MDF, as well as warping issues, it is not a suitable material to make frames out of. Further research and development will be needed to create a frame that avoids those issues and offers performance comparable or better than MDF. As of right now, we will not be moving forward with manufacturing HDPE frames. Please stay tuned for more updates on frame development, and if you have any suggestions for other materials we can try, make sure to get in touch!

One of the key areas that we strive to improve on in our manufacturing process is with the quality of the 3D prints in the Mill One kits. Our 3D printed part quality is an area that has a lot of room to grow in terms of improving quality. We have worked with our customers and listened to their suggestions to improve print quality, and over the last couple of months, our prints have become stronger, more consistent, and more precise. Making these improvements have involved testing different print settings, nozzle sizes, bed surfaces, and materials.

One other step that we have taken in improving print quality has been to update our printer farm with two new Prusa i3 MK3 printers. This is to increase our print capacity, as well start replacing printers from our aging fleet. One of our longest lasting printers has close to 3000 hours of printing on it.

If you’re familiar with Prusa as a company, they build industry-leading printers known for their consistency and reliability. They are currently being used to print the ACME nut mounts and the angle mounts, which are parts that require good layer adhesion to provide high strength. Based on our initial tests with the ACME nut mounts, it appears that these new mounts are stronger and less prone to cracking than mounts made by other printers. We have one printer that has been working fairly reliably but still need to fix some things on the other Prusa to have it up and running properly.

Here are some other things that we have improved over the last couple months:

• Reduce Z banding on the electronics holder and cover
• Improve bed adhesion for the angle mounts
• Adjust tolerances on the nut catches on the ACME nut mounts
• Switch from using the Cetus printers for printing the ACME nut mounts over to the Wanhao i3 or Prusa printers to have a smoother bottom surface (the raft on the Cetus leaves a rough bottom surface)

We’re excited to be using these new printers for creating better parts and continually improving our kit!

Hey guys, it’s been a while since I’ve posted. It’s been really busy at Sienci Labs, sending out machines and working on some new cool things. But we do have some really cool news that I want to share.

We now have Sienci Mill Ones on every continent (minus Antartica)! Although we actually met this milestone a long time ago, we only just realized it when we got orders from Puerto Rico and India this past week. This is a really amazing milestone for us, especially how we’ve seen the diverse number of applications that the Mill One has been used in almost 30 different countries.

If you have any friends in Antartica who might need a small desktop CNC machine, make sure to let them know about us!

A couple of users have reported that their Z axis drops during situations such as when the machine stops moving, or when they turn on the router before a cut, which can be really annoying.  While the machine is supposed to have enough resistance from the v wheels and the leadscrew’s resistance to back drive to support a router, some machines may have such low friction in their Z axis that the weight of the router actually exceeds the resistance. You can either rotate the eccentric nuts to allow for more resistance on the Z axis, and/or the rest of this post will talk about another option.

This is where $1= 255 comes in. $1= 255 is a command that you can send to your Mill One that will hold all of your motors to prevent any of the axis from moving when the machine is stationary. This means that if you are experiencing your Z axis moving down, you can use this command to use the motor to hold the axis. Below is a detailed guide on using $1= 255. If you want to learn what $1= 255, and other setting commands mean, check out this page or go to the end of the page.

Step 1) 

Connect your Mill One to your computer and open up Universal Gcode Sender. You can use other gcode senders for this, and the process is the same, but the images below are from Universal Gcode Sender.

If you already have your Mill One connected previously, it is recommended that you open and close the connection.

Step 2)

Give the Mill One a minute to load. You should see the message “Grbl 1.1e [‘$’ for help]” and a string of settings come up in the console.

Step 3)

Into the command box, type in $1= 255.

Press enter. You should see the next entry in the console to say

“>>> $1= 255
ok”

Step 4)

Use the keyboard controls or the onboard jogging controls on Universal Gcode Sender to move one of the axis. You will notice that the motors are now powered on and you cannot move the axis by hand. This will prevent the Z axis from falling when the machine is not in motion.

To turn off motors, follow the same steps, but send the command $1= 25. This will allow the motors to turn off. It is recommended that when you are not using the machine, to unplug the machine from mains power or ensure that the motors are turned off with this command.

How does this work? Here is an excerpt from the Grbl 1.1v configuration page:

$1 – Step idle delay, milliseconds

Every time your steppers complete a motion and come to a stop, Grbl will delay disabling the steppers by this value. OR, you can always keep your axes enabled (powered so as to hold position) by setting this value to the maximum 255 milliseconds. Again, just to repeat, you can keep all axes always enabled by setting $1=255.

The stepper idle lock time is the time length Grbl will keep the steppers locked before disabling. Depending on the system, you can set this to zero and disable it. On others, you may need 25-50 milliseconds to make sure your axes come to a complete stop before disabling. This is to help account for machine motors that do not like to be left on for long periods of time without doing something. Also, keep in mind that some stepper drivers don’t remember which micro step they stopped on, so when you re-enable, you may witness some ‘lost’ steps due to this. In this case, just keep your steppers enabled via $1=255.