July 19 – July 26, 2024 “Photo Art Projects” Contest

Happy Friday, everyone! Thanks for sharing your summer-themed projects made with the LongMill/AltMill.

Last Week’s Winners

We are happy to announce that Chuck Lalonde, Georges Côté, Brian Slevin, and Tom Pulles are the summer-themed projects contest winners. Watch out for a prize!

This Week’s Theme: Photo Art Projects

This week’s theme is “photo art projects.” Share your beautiful photo art made with your LongMill/AltMill/LaserBeam for a chance to win prizes!

Have ideas for themes? Let us know by commenting below!

Happy creating!

July 12 – July 19, 2024 “Summer-Themed Projects” Contest

Hi everyone! Thank you for posting your film-themed projects made on the LongMill/AltMill with us.

Last Week’s Winners

We are happy to announce that Georges Côté, Kenneth Key, Derick Bond, Adam M Lehman, Mike Wentink, and Ray Alires are the film-themed projects contest winners. A prize is on its way!

This Week’s Theme: Summer-Themed Projects

This week, embrace the Summertime theme! Share your LongMill creations that capture the season’s essence, from beach-themed artwork to outdoor furniture. Showcase your summer-inspired items for a chance to win cool prizes.

Have ideas for themes? Let us know by commenting below!

Happy crafting!

July 5 – July 12, 2024 “Film-Themed Projects” Contest

Happy Friday! Thanks for sharing your first projects made on the LongMill with us.

Last Week’s Winners

We are happy to announce that Barry Reesor, Barry Johns, Paul Aboueid, Donna Koster, Sam Klein, and Joel Lauterbach are the first projects contest winners. Watch out for a prize!

This Week’s Theme: Filmed-Themed Projects

This week’s theme is “film-themed projects.” Share your best film-themed creations made with your LongMill, and we’ll choose our favorites to win prizes!

Have ideas for themes? Let us know by commenting below!

Happy making!

Everything You Need to Know About the LongMill Spindle and Dust Shoe Kit

Hey guys, Johann here. Ever since we announced the Sienci spindle for the Altmill, there has been a tremendous amount of interest from the community in bringing a Sienci-supported spindle option to the LongMill platform. While it has always been our intention to do so, we were busy finishing up the AltMill and other projects, which prevented us from giving this project the due diligence that it deserves.

If you want to read about our previous thoughts, testing, and opinions about spindles for the LongMill, check out this blog post.

The LongMill Spindle and Dust Shoe Kit is now available in our store. First orders are expected to ship August/September 2024

Below is our analysis and additional info about ordering the kit.

TLDR Version

  • It’s about half as loud as a router
  • Easy to connect 
  • Offers precise control over your spindle
  • New features and functionality when paired with the SuperLongBoard.
  • Offers gains in performance over 20,000 rpm
  • Orders are open now and will ship August/September 2024

Key benefits 


In a previous survey of the LongMill community, most people placed “lower noise” as their second highest priority feature (only behind auto tool changing).

In our testing, a 1.5kW spindle is consistently 10dBA quieter than the Makita router at every speed, which makes it a drop-in upgrade that is easily half as loud (half the noise every 10dBA). While a water-cooled spindle would be even quieter, we believed that a small amount of extra noise was a reasonable tradeoff to the extra complexity of a water cooling system.

For some context, this air-cooled spindle produces less noise than the quietest of dust collectors/shop vacs in most use cases up to 23,000RPM.

Hear the difference in volume and the quality of sound for yourself

Plug and Play/Easy to Install

The Sienci spindle comes pre-wired, pre-programmed, and connects to your controller with a single RJ11 Cable (a telephone cable). As with all of our other accessories for the LongMill, come with excellent resources and support. We are currently finalizing the installation guide to upload to our resources site soon.

One wire to rule them all

Advanced Spindle Control

Another benefit of a spindle system is that you can control the start/stop and speed of the spindle directly from your g-code sender or gSender.  With this digital interface, you:

  • Can precisely control the speed of your spindle down to the single RPM
  • Know when your spindle is at speed
  • Know if your spindle stalls 
  • Communication between the VFD and gSender to improve the chances for job recovery in the event of a failure
No guesswork speed control
Spindle error feedback

Caveats, Provisos, Warnings, and Disclaimers

Marginal Cutting Performance Gains

This is an area we spent a lot of time and effort digging into since there are varying performance claims floating around the Internet and we’d like to give you our conclusions with some hard numbers. This of course pertains to our product in general, but likely to any spindle kit on the market. We believe we have conducted the most thorough testing and investigation in the hobby space for spindles.

A single run of our cutting test, out of more than a hundred
Speed – Torque characteristics of the Makita vs Sienci spindle
Speed – Power characteristics of the Makita vs Sienci spindle

The key takeaway from our testing is that the spindle is not dramatically more powerful than the router. The spindle has more power and torque at higher speeds, while the opposite is true for speeds below 20000 RPM (despite a higher risk of overheating for the Makita).

For 0.25” (¼ inch) tooling, there is little practical difference in cutting performance when upgrading to a spindle since you are limited to 400-500W cutting with the rigidity of the bit. With surfacing, you can use the full power of the spindle, but it also means that you will need to run both the machine and the spindle fast.

Surfacing Hard Maple End Grain at 1.2mm depth and 5000 mm/min (800W-1000W)

SuperLongBoard as a requirement

To take full advantage of the spindle, including the advanced control features detailed above and the all-important partial holding current feature available only with grblHAL, we highly recommend that you upgrade to the SuperLongBoard.

While it is possible to adapt this spindle kit for use on the LongBoard (and we will release more information on how that can be accomplished), here are 6 key disadvantages that you should be aware of:

  1. We will consider this a DIY configuration and support and resources will be limited
  2. Start-stop control will be unavailable without a reflash of the firmware and additional components
  3. The VFD will have to be re-programmed
  4. Holding current must be applied in full which can overheat the drivers and motors
  5. No stall detection or any other advanced features that are currently in development
  6. High-speed machine movements (>4000mm/min) that suit the spindle are unavailable due to legacy driver stability issues.

Dust shoe hose size

The spindle is designed with dust collectors, not shop vacs in mind and as such fits 4” dust hoses by default. To use shop vacs with the dust shoe, you will need to purchase a commonly available 2.5” to 4” adapter (Example found here on  Amazon). We are trying to see if we can offer an adapter at some point, but there are no commitments on this item just yet.

Additionally, the original dust shoe used on the LongMill is not compatible with the 80mm spindle. The kit comes with a larger dust shoe included.

The dust shoe performs well with a shop vac attachment

Spindle Mount

This spindle is 80mm in diameter and the mount will be included in the LongMill Spindle and Dust Shoe Kit.

The main difference between the AltMill Spindle and Dust Shoe Kit and the LongMill Spindle and Dust Shoe Kit is the addition of the 80mm mount. You can also purchase the mount separately from our store.

Additional Information and Insights

Cutting Volume and Accessories Compatibility

We’ve checked the spindle + dust shoe against every single LongMill configuration ever released (including the MK2 extension kits), and there is no loss to cutting volume to any configuration (the MK2 front feet can technically can collide with the dust shoe, but the overlap is only 2mm (1/16”) and only occurs when you are cutting below the wasteboard).

Clearance is clearance Clarence

The story is a bit different with the Vortex which is a lot more height constrained. The additional length of the spindle collet eats into the cutting (and probing) height requirements of the Vortex, and for every machine configuration we recommend raising the feet of the machine up by 1.5” (2 sheets of 0.75” MDF) to restore the original cutting volume.

Insufficient clearance for the Vortex without raising the machine

Weight of Spindle and Mechanical Effects

The new spindle is 2.8kg (6lbs) heavier than the Makita RT0701C router’s 1.8kg (4lbs) which may seem a lot, but according to our calculations and testing, this has a negligible effect on the X and Y axis, requiring only an extra 1-2% of available torque from the steppers motors even accelerating to 5500mm/min. The remaining torque should also be sufficient in making the hypothetical 1.5kW cuts which typically require less than 100N in cutting force.

Force generated by the stepper motors at varying speeds
Force requirements for a 1.5kW cut
Jogging the machine at full speed

With regards to the Z-axis, the additional weight can consume up to 27% of total available torque of the motor. Having said that, since boring operations typically involve pushing the bit down into the material, the additional weight is not an issue in such a scenario.

Making a few holes in walnut

Lastly, it’s also worth mentioning that although the steppers can hold and push the spindle with an adequate amount of force, aggressive cutting can still result in significant deflection of the bit and cause your cuts to come out untrue, so after any aggressive cuts, you should always follow up with a skim/spring or finishing pass to make sure that the surface is accurate and smooth.


While the Makita RT0701 is an excellent option and recommended for most LongMill users, the Spindle Kit offers a high-quality, simple, and well-supported option for the community. To learn more and to order, make sure to check out the store page here.

LongMill Spindle and Dust Shoe Kit


This is a pre-order. Spindle Kits are expected to start shipping in August 2024. TheLongMill Spindle and Dust Shoe Kit is designed to unleash the capabilities of the LongMill as a plug-and-play replacement for the standard Makita RT0701 router. For everything you should know about this product, please read this article. Each kit comes with:…

94 in stock

July 2024 Production Updates

Hey everyone, welcome back for our July 2024 production updates.


X-axis assembly
Y-axis assembly

As we alluded to in the last update, we were hoping to start shipping AltMills mid-June. However, we did run into a few issues:

  • There were some issues in the wiring for the spindles, which were done manually in-house to get some put together. We should have new ones arriving soon
  • There were some parts on hold for coating due to some scheduling issues in the plant.

However, we are excited to announce we have started shipping AltMills! Horray!

You can also find resources for AltMill here: https://resources.sienci.com/view/am-welcome/

We’ve brought on several new people to help on the production and operations side of the AltMill so that we can ramp up shipping and iron out any kinks as they come up during our production.

Also… new gSender update is expected to come in the second week of July, which will contain settings and defaults for AltMill.

Our first batch of 200 is now sold out, and we are working on stocking up on our second batch. This means that new orders will be part of the second batch. The shipping schedule will also be largely determined by the timely arrival of those parts.

AltMill/LongMill Spindle Kit

I’m not sure where I should add some extra info about the AltMill Spindle Kit, with regards to LongMill compatibility but I’ll throw that in here for now.


We have gotten a lot of requests for the AltMill Spindle Kit to be available as a separate purchase, and we have planned to have it available since the beginning. It is now available in our store.

This also brought up a lot of interest in official spindle support for the LongMill. Some of the factors why we are working on supporting a spindle option include:

  • Now that we have established a spindle testing and QC procedure for the AltMill spindles, we can use the same techniques for supporting LongMill as well
  • We have created a relationship with an established spindle manufacturer who can build to our specifications
  • The production of the AltMill provides enough volume for us to order more spindles, which brings the overall cost down.
  • The addition of the SLB greatly improves and simplifies the installation and setup between the controller and the VFD. The SLB and the VFD used in this package allow for RS485 communication which allows for control of the spindle speed directly through gcode and the gSender interface, and can allow for features such as “wait for spindle”, which allows the spindle to get up to speed before starting the cut.
  • This interface also allows for additional safety features such as being able to stop due to spindle issues and shut things down in the case of an emergency (with the SLB)
  • With the improved motor holding capabilities of the SLB, the Z axis is better able to support the weight of the axis.

I should include that the spindle can be used with the original LongBoard, however there are some limitations

  • Speed control through code or gSender may not be supported out of the box. It is possible to control it using the PWM, but a converter from 5V PWM to 0-10V analogue may be needed. The spindle can be controlled manually and turned on and off directly from the VFD, and so it can still be used this way.
  • The added weight of the spindle may be enough to cause the Z axis to come down when no power is going to the motors. To mitigate this, users can use the command “$1=255”, which causes the drivers to hold their position. However, this constantly powers the motors and use a lot of power. There is no way to control how much power goes to the motor and each motor draws full current when this setting is turned on. The SLB allows for specific current values when the machine is stationary, so power draw can be controlled.

With that in mind, to take advantage of the new features, it is strongly recommended to use the spindle with the SLB.

We have ordered 200 spindle kits to finish the first batch of AltMills, plus an additional 200 kits that will be shared between AltMill sales and separate spindle kit sales. These are expected to arrive in mid-August.

At this stage, the spindle used for the AltMill has been tested on the LongMill and work is being done to have completed support documentation for the LongMill. Users can order the AltMill spindle kit for their LongMills. At this moment, we don’t officially support it, but we will officially support it once our testing is complete.

This also brings up the consideration of potential support for non-Sienci machines. If you have a machine that you want us to consider working with for the spindle kit, let us know.

Additionally, we’ve checked the fit for the 80mm dust shoe to be compatible between the AltMill and LongMill. We are also working on supporting 2.5in hoses (the 80mm dust shoe uses 4in at the moment).

LongMill MK2.5

LongMill MK2.5 machine are shipping now. We are working to get lead times down as we work our way through our list of orders, but at the time of writing, most are shipping within 3-4 weeks. Please refer to the order page information for most up-to-date estimates.

More shipments continue to roll in for LongMill production, and we aren’t expecting much news at this moment for production.


Vortex orders continue to ship out. We’re excited to announce that we are working on the official version of the independent 4th axis, which combines and external driver with the SLB to allow for all axis to move simultaneously. For those who don’t know, the Vortex is currently connected to the Y-axis drivers so that you can switch between either the Y axis or the rotary axis. The SLB has an external driver output which allows another driver to be used to control another motor, in this case, the Vortex.

4th axis support is already officially supported and documented on the Resources. Users can integrate their own drivers for full 4th-axis support. The new development we are doing will be a plug-and-play option for the AltMill and SLB-integrated LongMills.

Given that we are purchasing a lot of closed-loop steppers, we have decided that the cheapest and easiest way to provide the 4th-axis support was to integrate them. While this might be little bit wasteful for existing users, since it leaves one unused motor in the conversion, in the long run as we move towards the SLB adoption, it will be the simplest and best option for this application.



A new batch of SLBs has arrived and folks who have ordered them after our first batch of 500 units should be getting them now.

A small change that’s coming to the SLB will be in the design of the e-stops. Our initial version had an illuminated switch. However, we found that it would make more sense to have lights on the case itself since it offered more button choices and we wanted to have something more durable/easier to replace. Both buttons work the same and are interchangeable so there likely won’t be any particular notice on when this change happens. We have another 500 of the original version in production now and we’re getting things together to make another 1000 sets.


I guess one of the things that the Sprouter project has become is an exercise in understanding spindles, routers, and machining science in general.

We have received another set of prototype motors and Johann has been testing that plus the Makita router and 1.5KW spindle. Here’s a breakdown:

  • At the lowest level, the Makita has the highest torque, but drops proportionally to the speed (green)
  • The spindle keeps a fairly flat torque curve, but needs to spin above 20,000RPM to see power advantages over the Makita (blue)
  • The BLDC/Sprouter tested in various configurations show the potential to have a higher power output between the spindle and Makita router.

It also looks like the sensorless BLDC speed response was greatly improved in the new iteration. However, because the motor was built and tested to run at 160V (to be voltage compatible for both 110V and 220V), testing at 220V gives very good results, testing at 110V does not have an acceptable response time.

The manufacturer is currently working on a new version specifically tested and manufactured for 110V use only, which in theory should have similar performance as our current version, with the compatibility for 110V.

I should include some disclaimers here:

  • While this shows the maximum power output, it may not reflect real-life optimal use. For example, running the Makita at it’s highest power level can destroy itself, whereas a spindle/sprouter is designed to run at the higher level for longer.
  • Power output was calculated through indirectly with speed and torque simulation under real-life cutting loads, as our dyno cannot handle this level of power at this moment, it would be

Here are some current conclusions:

  • The BLDC, after all the work, shows a lot of promise. These are results that we feel are “extraordinary”, which is that because they are so good, we have to make sure they are actually true. If the results are actually accurate, then in theory, it is possible to design a spindle using BLDC that could outperform a 1.5KW spindle.
  • There is also a massive potential for this technology to be used in more applications outside just our machines. Perhaps it opens up a new roadmap for the company? We feel that after all of this work and development focused in this space, we may be one of, if not the only company doing this R&D, and perhaps the only one who is in the position to put out a new revolutionary (haha, bad pun), spindle design and platform.
  • This also feels like uncharted territory, so there’s a lot of business end planning we need to do to decide how we want to keep committing to this project.

In other news, the testing of the Makita clone was not very good, as the speed control was poor. After some back and forth with the manufacturer, we are expecting to have a new sample with much-improved speed control soon. This version won’t have the 5V PWM input yet, but we should know if the performance is acceptable before moving onto this next step.

Panel Computer

We have now received the new batch of fanless panel computers and they are pretty great.


There are a few things we’re trying to decide on. One of them is which operating system to use. The two main contenders are Windows 11 and Linux. These are some of the things we are trying to weigh:

  • Linux is free. Windows on the other hand, is pretty configurable, but does cost money. We aren’t exactly sure what that cost would be, as some sources offer it for $10-65USD, whereas the Microsoft store sells them directly for around $139USD. For us to be able to offer Windows as an option, we would need to navigate getting the licenses legally.
  • Pretty much everyone either knows how to use Windows or has used it at some point. Linux on the other hand has a pretty small following. This may make some of the support for Linux more difficult, since there are a lot of info and resources available for Windows.
  • Based on initial testing, the performance of gSender on the same hardware running Linux is slightly less fast than on Windows. We are still trying to iron this out, but we suspect that due to the differences in the drivers and optimization, going with Linux may mean there needs to be some additional optimization on gSender to make it compatible.

Here are my current thoughts.

  • If we can get Windows licenses at a small cost, it would be a better option because we know that it works and people are familiar with it. We would of course have to pass this cost off to the customer, but I think people would be willing to pay a little extra for being able to use the platform they are familiar with.
  • We can create images for both Windows and Linux, and they can be available for anyone to download and use. They should in theory work for both the panel computers we will sell and other computers as well, but we’ll only know once we do the testing. This means that if people want to switch between operating systems, or use their own computers, they can do that.

Currently, we are:

  • Looking for a way to get legitimate Windows licenses
  • Testing with Windows and Linux
  • Testing and designing ways to attach the panel computer to the machine

If you want to provide any extra feedback for the Panel Computer, please feel free to fill out the survey.

June 28 – July 5, 2024 “First Projects” Contest

Hi everyone! Thank you for posting your acrylic projects made on the LongMill with us.

Last Week’s Winners

We are happy to announce that Jacob Columbus, Robert Terry, Brandon Ellis, Kenny Swett, Bill Pare, and Louis Van Pelt are the acrylic projects contest winners. A prize is on its way!

P.S. We will be closed on Monday, July 1st for Canada Day and back in the office on Tuesday, July 2nd.

This Week’s Theme: First Projects

For this week’s contest, share your very first project or any initial work you’ve done on the LongMill. Submit your entry for a chance to win free prizes!

Have ideas for themes? Let us know by commenting below!

Happy building!

June 21 – June 28, 2024 “Acrylic Projects” Contest

Happy Friday! Thanks for sharing your animal projects made on the LongMill.

Last Week’s Winners

We are happy to announce that Taylor Marie, Bernie Strybos, Rick Suleman, Chris Pare, Robert Mohr, and Tony Gallagher are the animal projects contest winners. Watch out for a prize!

This Week’s Theme: Acrylic Projects

This week’s theme is “acrylic projects”! Share your LongMill creations featuring acrylic as the main material for a chance to win free prizes in our contest!

Have ideas for themes? Let us know by commenting below!

Happy creating!

June 14 – June 21, 2024 “Animal Projects” Contest

Hi everyone! Thank you for sharing your LongMill projects and the lessons you learned from making them.

Last Week’s Winners

We are happy to announce that Shawn P Palmer, Tim Goodyke, Spamming Eddie, Andre Arseneault, Don Rideout, and Jim Shuler, are the something learned projects contest winners. A prize is on its way!

This Week’s Theme: Animal Projects

This week’s theme is “animal projects.” Share your favorite animal-themed projects for a chance to win free swag!

Have ideas for themes? Let us know by commenting below!

Happy crafting!

June 7 – June 14, 2024 “Something Learned Projects” Contest

Happy Friday! Thank you to everyone who shared their incredible accessory projects made with the LongMill.

Last Week’s Winners

We are happy to announce that Alex Chopek, Dave Parkerson, Dean Goulet, Don Rideout, Ed Lagace, and Matt Osterhaus are the accessory projects contest winners. Watch out for a prize!

This Week’s Theme: Something Learned Projects

This week’s theme is “something learned projects”! Share a project you made with your LongMill and tell us what you learned from making it. Post your project with a caption about your lesson, and we’ll send awesome prizes to our favorites.

Have ideas for themes? Let us know by commenting down below!

Happy making!

May 31 – June 7, 2024 “Accessory Projects” Contest

Hi everyone! Thank you for posting your LongMill-made kitchen projects with us.

Last Week’s Winners

We are happy to announce that Russell Dillon, Tom Pulles, Bruce Forbes, Bill Pare, BuiltSmart Woodworking, and Raul Nemes are the kitchen projects contest winners. A prize is on its way!

This Week’s Theme: Accessory Projects

This week’s theme is “Accessory Projects.” Show us your LongMill creations like jewelry, phone cases, stands, keychains, home decor, and more. We’ll reward the winners with fantastic prizes!

Have ideas for themes? Let us know by commenting below!

Happy building!