If you’re one of my YouTube followers, you’ve likely caught wind of my recent acquisition – a used Kitamura Mycenter Zero CNC machine, for $3000.

In this YouTube short, I show the delivery of my CNC machine and a walkaround of this 1992 marvel, running on the reliable Fanuc 0M-C CNC controller. However, there’s a catch with these vintage controllers – they lack the solid-state memory we take for granted today. When the backup battery runs dry, you risk losing all your parameters, rendering your CNC inoperable!

To safeguard against such a predicament, a common practice is to back up the parameters. I wasted no time crafting a custom DB26 to DB9 DNC cable for my Fanuc 0M and efficiently read out the parameters over DNC.

I quickly made a custom DB26 -> DB9 DNC cable for my fanuc 0m and read out the parameters over DNC.

I followed a useful video tutorial to guide me through the parameter backup process, ensuring that even if the worst happens, I can quickly recover my Kitamura Mycenter Zero’s vital settings.

For your convenience, here are the backup files containing the parameters:

I hope this information proves valuable for anyone facing a similar challenge with their Kitamura Mycenter Zero CNC. Don’t let lost parameters stall your projects – stay prepared!

Introduction

In the realm of precision engineering, top-notch precision ground and lapped granite measuring parallels are essential for accurate and stable measuring and inspection processes. However, the cost of premium parallels can be prohibitive, ranging from $500 to $3,000, making it challenging for hobbyists and small-scale machinists.

Venturing into the world of affordable alternatives, I discovered Chinese granite parallels and decided to share my experience with these budget-friendly tools that exceeded my expectations.

Discovering and Ordering Chinese Granite Parallels

Navigating the complexities of ordering from a Chinese supplier that only communicates in Chinese and requires payment through a Chinese bank account [Insert my lovely wife here], I took a leap of faith and ordered a set of granite measuring parallels.

To save on shipping costs, I opted for the economical One Belt One Road rail transport initiative, which delivered the package to my doorstep within a month.

Upon unboxing the well-packaged granite parallels, I was impressed by their visual finish and clean, chamfered edges. Each parallel and granite square came with a factory measurement certificate, verifying their 000 grade (Chinese national standard) quality.

The granite parallels held up well within the tolerances specified by the manufacturer (at least how well you can measure using primitive tools). They were flat and parallel, indicating a high degree of precision.

Sharing My Findings with Friends

After validating the quality and performance of these affordable granite parallels, I shared my findings with friends in the machining community. Their interest led me to order more sets, which I distributed among them, receiving positive feedback on the value for money these Chinese granite parallels offered.

I ordered a few more sets and distributed them among my friends, who were equally impressed by the value for money these Chinese granite parallels offered. They have since become a popular choice among our community, especially for those seeking cost-effective options without compromising on quality.

One of my friends out of the machining community who got two parallels even made a video showing its performance:

[Note turn sound off!!]

Conclusion

My experience purchasing and testing Chinese granite measuring parallels has been enlightening, proving that budget-friendly alternatives can provide satisfactory results for hobbyists and small-scale machinists. While caution is necessary when purchasing from overseas suppliers, I believe it’s worth exploring affordable options like these Chinese granite parallels, as they can save you a significant amount of money without sacrificing quality.

In addition to my own positive experience, my friends in the machining community have also found these affordable granite parallels to be a game-changer in their work. These tools have enabled them to achieve high levels of accuracy and precision in their projects without breaking the bank.

Ultimately, the key takeaway is to keep an open mind when searching for affordable tools and equipment, as it’s possible to find hidden gems that offer excellent value for money. Chinese granite parallels are just one example of such a discovery that can benefit precision engineering enthusiasts on a budget.

Interested in Getting a Set?

Occasionally, I go through the trouble to import a batch of these parallels from China. If you’re interested, feel free to contact me through this page or on Discord. I will also be sending a set to a nationally recognized metrology lab to verify the factory’s measurement certificate.

Have you tried any budget-friendly tools that have exceeded your expectations? Share your experiences in the comments below!

Introduction

When my laptop met its untimely demise, I was on the hunt for a new computer to run LinuxCNC for my CNC projects. In this post, I’ll discuss my experience with the Dell Optiplex 7050 Mini, featuring an Intel Core i5-6500 processor, and determine whether it’s the right choice for LinuxCNC enthusiasts like myself.

Dell Optiplex 7050 Mini – Key Specs

The Dell Optiplex 7050 Mini is a compact, yet powerful computer that comes with the following specs:

• Intel Core i5-6500 Processor (6M Cache, up to 3.60 GHz)
  
• Up to 64GB DDR4 RAM – Mine is fitted with 8GB
  
• Integrated Intel HD Graphics 530

• Penty of USB ports , and a 256GB SSD fitted

• Plenty of these units are available used through third parties. I bought mine for 150$

These specs seemed promising for running LinuxCNC, but the true test would come in the form of latency testing and real-world performance.

Installing Debian 12 + LinuxCNC + Probe basic in 2023

I had previously made a post about installing LinuxCNC 2.8.4 with Probe Basic, but unfortunately, there are several broken repositories in the probe basic installation script… so I was forced to install LinuxCNC 2.9 on Debian 12 using the instructions posted on the developer’s website and that worked … mostly. So I devoted a new post relating to how I installed it and the small challenges I faced.

Read more about it here: [placeholder]

Latency Testing for Dell Optiplex 7050 Mini LinuxCNC

Latency is a critical factor for LinuxCNC, as it determines the system’s ability to respond to changes in the CNC machine’s position. Lower latency results in smoother and more accurate operation. To evaluate the Dell Optiplex 7050 Mini, I used the LinuxCNC ‘latency-test’ utility to measure the maximum base thread and servo thread latencies.

As I’m using a Mesa 7i96S the base thread is not actually not applicable but I still had it running in my tests.

LinuxCNC BIOS Modifications for Dell Optiplex 7050 Mini

I did some small modifications in the BIOS setting to hopefully make LinuxCNC run smoother on the Dell Optiplex 7050 Mini. I basically disabled any power-saving features, sleeping states, and any virtualization options. I left the “turbo” feature of the CPU on, as I was unsure if this would benefit or harm the latency results.

Grub Modifications for Dell Optiplex 7050 Mini LinuxCNC

I did some modifications in the Grub including isolating CPU cores for LinuxCNC and reducing sleep modes and states for the Intel i5-6500 CPU on the Dell Optiplex 7050 Mini.

Follow the instructions provided in the original article to perform these modifications.

at the terminal, type:

sudo nano /etc/default/grub

when this opens, add this line (for a 4 core system):
GRUB_CMDLINE_LINUX_DEFAULT="isolcpus=2,3,4 intel_idle.max_cstate=0 processor.max_cstate=0 idle=poll"

You can add this below the other command line parameters in the file. Then hit control-x to save it.

then type:

sudo /sbin/update-grub

then reboot.

Verify that it worked by doing:
sudo dmesg
or
cat /proc/cmdline
which shows the parameters used for the current bootup

You should see your isolcpus command in that list.

This modification was inspired by this PrintNC wiki article.

Note: I have not independently verified if the idle max, state and idle poll settings benefit.

Comparing the Modifications

I read somewhere that there might be a performance benefit by isolating a CPU core pair i.e. 2,3 for a 4 core system instead of separating random cores so I did a quick test:

This test was conducted with 4x glxgears running and YouTube full HD video in the background.

The isolcpus 1,2,3 option resulted in lower latency, hence that is what I kept.

Results of Dell Optiplex 7050 Mini LinuxCNC Latency Test

The Dell Optiplex 7050 Mini performed admirably in the latency tests. The measured latencies were well below the recommended maximums for LinuxCNC, which means that LinuxCNC should be running smoothly on the Dell Optiplex 7050 Mini. However, it’s worth noting that individual results may vary depending on the specific configuration of the computer, as well as the connected CNC hardware. I’m utilizing a Mesa board for the direct control of my servo motors, so the latency requirements are also much less strict.

Conclusion: Dell Optiplex 7050 Mini LinuxCNC – A Solid Choice

Based on my experience and the latency test results, the Dell Optiplex 7050 Mini with the Intel Core i5-6500 processor is a solid choice for running LinuxCNC. Its compact form factor, powerful processor, and compatibility with Linux make it a reliable option for CNC enthusiasts. At ~$120 for a fully tested and working unit with 8GB RAM and a 256GB SSD, the Dell Optiplex 7050 Mini LinuxCNC is also cost-effective.

However, keep in mind that the ideal computer for LinuxCNC depends on your specific needs and budget. It’s essential to evaluate your requirements and research other options before making a final decision. Overall, the Dell Optiplex 7050 Mini LinuxCNC stands out as a cost-effective and capable choice for those looking to run LinuxCNC on a reliable system.

The replication method is a widely used technique in manufacturing and metrology to obtain accurate copies of a surface. The method involves replicating the surface of a reference material onto a workpiece using a medium such as metalized epoxy. This article provides an overview of the replication method, including its advantages, limitations, and applications.

Replication Method:

The replication method involves using a medium such as metalized epoxy to make a copy of the surface of a reference material, such as a granite surface plate to a workpiece. The surface to be replicated is first cleaned and coated with a thin layer of release agent, typically some kind of wax. The release agent is allowed to dry and is buffed to a shiny surface before the epoxy is applied. The epoxy is applied to the setup by pouring or injecting it into the setup and then allowed to cure. Once the epoxy is cured, it is peeled (or hammered) of the reference material, leaving behind an exact replica of the surface.

Advantages of the Replication Method:

One of the main advantages of the replication method is its ability to produce accurate copies of a surface. The method is also relatively easy to perform and requires only basic equipment and materials. Another advantage of the replication method is that it can be used to replicate surfaces of different shapes and sizes, making it suitable for a wide range of applications.

Limitations of the Replication Method:

While the replication method is generally accurate, it is important to note that it is subject to certain limitations. One limitation is that the replication method can only produce a replica of the surface that is in contact with the reference material. If the reference material has any defects or irregularities, these will be replicated onto the workpiece.

Applications of Replication Method:

The replication method is widely used in metrology to produce accurate copies of surfaces for measurement purposes. It is also used in manufacturing to replicate surfaces for quality control and inspection. Additionally, the replication method can be used in the restoration of damaged surfaces, such as those found on antique furniture or architectural features.

Resources:

Academia:

There is a book from the 80’s or 90’s by a professor of a US university who writes about the surfaces replication method, and how they used it to make a giant 5 axis grinder… I just cant find it at this moment…

Ah, here it is!

Principles of Rapid Machine Design – MIT – Eberhard Bamberg:

https://my.mech.utah.edu/~bamberg/research/PrinciplesOfRapidMachineDesign/Principles%20of%20Rapid%20Machine%20Design.pdf

At-scale use of the replication method for big cnc machines – Rampf group:

https://www.rampf-group.com/en/aktuelles/blog/2021/how-to-2-replicating-mineral-casting-components-with-maximum-accuracy/

Replication techniques and portable machining in machine tool rebuilding – Molglice:

http://www.moglice.com/articles/replication_techniques/wrotethebook.html

PRECISION the easy way, making CNC parts too big for a hobby mill – @floweringelbow:

DIY experiment:

With most DIY builds the most difficult part is creating flat mounting surfaces for your carriages and rails. In my Mightymill build, I have the same challenges.

Creating precision surface copies using metalized epoxy

Total Time: 9 hours

Prepare your workpiece

Make sure it is free of oil, and has a decent amount of surface roughness for the epoxy to adhere to.

Prepare the reference surface

I used Miracle wax no.8 as a release agent. Follow the manufacturer’s instructions (I did 3 coats) with buffing in between. I used a 40$ <2um error small granite surface plate.

Prepare the metalized epoxy

I used West epoxy 105 + 206 hardner, although I’d think 209 might even work better. I did a 50/50 mix of epoxy + iron powder (<63um particle size).

Tape off your part

Note: I used a 3-4mm thick parallel to regulate the thickness of my epoxy layer.

Pour the epoxy

Make sure you remove all air and have proper coverage. This is actually the most difficult part

Let the epoxy cure

I think I let mine set for about 12 hours

Remove from the reference surface and inspect

Any overflowing epoxy you can just hit off with a hammer or grind it away with a die grinder. The initial surface is quite rough due to the remaining release agent on there and any defects of your reference material.

Optimize the surface roughness and flatness

You can use either something like a 123 block + abrasive, a “kitchen” flattening stone, or any other relatively flat material. I used some dishwashing soap + the above-mentioned iron powder to basically do a lapping operation to the surface.

After about 3 – 5 minutes of lapping the surface should be smooth with most of the high sports removed.

Inspect and repeat

There are various ways to inspect surface flatness. I used a Mitutoyo indicator, a 123 block, and a high-precision HGW20CC block as my reference.

The initial flatness before the optimization stage was about 8um over the whole surface. After a cycle of 1-3 times of optimizing and inspection, it is <= 2um. Which equals my reference material. Lapping becomes challenging because the materials just want to stick together. The main issue at this point is that this is extremely difficult to measure.

As you are at or nearing the requirement of lab-based CMMS or optical measurement methods.

You could make this perfectly flat by doing this to 3 surfaces and using the Withworth 3 plate method.

Does it pull a vacuum?

yes: https://youtube.com/shorts/egtODwy4WiE

Estimated Cost: 5 USD

Supply:

• Slow cure no shrink epoxy such as West 105 + 206
• Iron powder <63um particle size
• Tape

Tools:

• 123 block

Materials: Workpiece Reference material Mold release wax

Conclusion:

The replication method is a simple yet effective technique for producing accurate copies of surfaces. While it has certain limitations, it is a valuable tool in metrology, manufacturing, and restoration. It allows a hobbyist or a professional to make micron-to-sub-micron accurate copies of reference surfaces. And thereby able to create flat surfaces for DIY CNC machines or metrology equipment at a relatively low cost and low effort.

But before we dive into the specific coatings, it’s important to understand what an endmill coating is and why it’s important. An endmill coating is a thin layer applied to the surface of an endmill, a type of cutting tool used in milling operations, to improve its performance and extend its lifespan. There are various types of coatings available, each designed to address specific issues and improve the tool’s performance in specific materials.

The choice of endmill coating is crucial because it can significantly impact the efficiency and accuracy of the milling process. A good coating can reduce tool wear, improve cutting speeds, and increase tool life, leading to cost savings and increased productivity. On the other hand, a poor coating choice can result in tool failure, poor surface finish, and increased cycle times.

When milling aluminum, it is essential to choose a coating that has excellent non-stick properties and prevents chip welding. This is because aluminum has a high affinity for sticking to cutting tools and is prone to chip welding, which can lead to tool failure and poor surface finish. A non-stick coating helps to reduce the risk of tool failure and improve the overall performance of the milling process.

What is an Endmill Coating and Why is it Important?

An endmill coating is a thin layer applied to the surface of an endmill, a type of cutting tool used in milling operations, to improve its performance and extend its lifespan. There are various types of coatings available, each designed to address specific issues and improve the tool’s performance in specific materials.

When milling aluminum, it is essential to choose a coating that has excellent non-stick properties and prevents chip welding. This is because aluminum has a high affinity for sticking to cutting tools and is prone to chip welding, which can lead to tool failure and poor surface finish. A non-stick coating helps to reduce the risk of tool failure and improve the overall performance of the milling process.

Best Endmill Coatings for Milling Aluminum

There are several endmill coatings available on the market, each with its unique properties and benefits. Some of the best coatings for milling aluminum are: Platit Naco-Blue, PCD (Polycrystalline Diamond), and Diamond-Like Carbon (DLC).

#1 PCD (Polycrystalline Diamond) Coating

PCD (Polycrystalline Diamond) is a superhard coating that is made up of diamond particles that are sintered together using a high-pressure, high-temperature process. It has a coefficient of friction of 0.1-0.3u and is known for its excellent wear resistance and ability to prevent chip welding, making it an ideal choice for milling aluminum. PCD coatings offer excellent lubricity and can withstand high cutting speeds, making them suitable for high-speed milling operations. They also offer excellent tool life and reduced tool wear, making them a cost-effective choice for milling aluminum.

One of the main advantages of PCD coatings is their excellent wear resistance, which allows them to maintain their performance for longer periods of time compared to other coatings. This can lead to increased productivity and cost savings by reducing the need for frequent tool changes. PCD coatings also offer excellent surface finish and can be used on a variety of materials, including aluminum, steel, and titanium. However, one of the main disadvantages of PCD coatings is their high cost, which can make them less cost-effective for some applications. They also require careful handling and storage to prevent damage and maintain their performance.

#2 Diamond-Like Carbon (DLC) Coating

Diamond-Like Carbon (DLC) is a hard, wear-resistant coating that is known for its excellent non-stick properties and low coefficient of friction of 0.1-0.2.

It is applied using a PVD process and is made up of a thin layer of amorphous carbon that contains small amounts of hydrogen and other elements. DLC coatings offer excellent wear resistance and can withstand high cutting speeds, making them suitable for high-speed milling operations. They also offer excellent tool life and reduced tool wear, making them a cost-effective choice for milling aluminum.

One of the main advantages of DLC coatings is their excellent non-stick properties, which helps to prevent chip welding and improve the surface finish of the milled parts. They also offer excellent lubricity and can be used on a variety of materials, including aluminum, steel, and titanium. However, one of the main disadvantages of DLC coatings is their sensitivity to temperature and humidity, which can affect their performance. They also require careful handling and storage to prevent damage and maintain their performance.

Platit DLC Coating Information Pamphlet

#3 Naco-Blue Coating (Platit nACo)

Platit Naco-Blue is a high-performance endmill coating that is known for its excellent non-stick properties and ability to prevent chip welding. It has a low coefficient of friction of 0.4u and is applied using a physical vapor deposition (PVD) process. It is made up of a thin layer of titanium nitride (TiN) with a thin layer of aluminum oxide AlTi(Si) on top. The TiN layer provides high hardness and wear resistance, while the AlTi(Si)N layer offers excellent lubricity and prevents chip welding.

One of the main advantages of Platit Naco-Blue coatings is their ability to reduce tool wear and improve cutting speeds, leading to increased productivity and cost savings. They also offer excellent surface finish and can be used on a variety of materials, including aluminum, steel, and titanium. However, one of the main disadvantages of Platit Naco-Blue coatings is that they can be brittle and prone to chipping if subjected to high impact forces. This can be mitigated by using a thicker coating or by applying a secondary coating for added toughness.

Platit nACo Coating Information Pamphlet

My personal experience and recommendations

In my experience, PCD (polycrystalline diamond) coating is excellent for creating mirror-like finishes on aluminum. However, the high cost of this coating means that I personally use APKT1135 R0.4 PCD inserts in combination with a BAP300R tool holder, only for the finish pass to maximize its lifespan.

For roughing, both DLC (diamond-like carbon) and Nano blue coatings work well. Personally, I prefer DLC coating as it still provides a good finish and is more affordable than PCD. It has better non-stick (chipweld) properties than Nono-blue coating.

I had good results with the 1 flute and 3 flute Dreanique DLC 5$ endmill from Aliexpress.

Nano blue coating is a good choice for a multi-material endmill that can handle aluminum and steel. This versatility makes it a useful general-purpose endmill coating.

Conclusion

In conclusion, choosing the right endmill coating is essential for efficient and accurate milling of aluminum. PCD, DLC and Platit Naco-Blue, coatings are some of the best options available, each offering unique properties and benefits for milling aluminum.

It is important to consider the specific needs of your application and choose a coating that offers the best balance of performance and cost-effectiveness. By choosing the right endmill coating, you can improve the efficiency and accuracy of your milling process, leading to increased productivity and cost savings.

However, there is no one-size-fits-all solution when it comes to endmill coatings. Different coatings are better suited for different materials and applications, and it is important to carefully consider the specific requirements of your operation before making a decision.

We would love to hear from you in the comments below about your experiences with endmill coatings for milling aluminum. What coatings have you used, and what were the results? What factors did you consider when choosing a coating? Share your thoughts and experiences with us and let’s continue the discussion!

Total Time: 1 hour

Download the required software tools

Download LinuxCNC 2.8.4 Debian 10 Buster PREEMPT-RT ISO
Download Rufus 3.2.0 https://rufus.ie/en/

Format USB stick and make bootable USB

WARNING: Your USB stick will be formatted, you will lose any info that is on there.

Insert USB stick, open RUFUS , select correct USB drive/partition,select linuxcnc ISO and press start.

If you get the POPUP “ISOHybrid image detected -> Select Write in ISO image mode

If you get the popup “Download required” accept yes to get the required files

Boot from USB stick

Insert the USB stick in the device you want to install linuxcnc to. Turn on the device and select USB stick to boot from.
(google if you do not know how; this is universal knowledge)

Install Debian

Start installer and follow installation instructions. In case of troubles there are plenty of videos online regarding how to fix issues.

I found this video quite useful.

Install probe basic

Follow the instruction listed on kcjengr.github.io from step #1

[This is a summary for source look at kcjengr link above]

1- Update the operating system
After installation, copy the following in the main terminal one line at a time and hit enter, select Y for yes if asked at any point during installation:

sudo apt update
sudo apt upgrade

2- Start Linuxcnc first time
Now linuxcnc needs to be started for the first time for it to create its directory folders. This can be done by the drop down menu and selecting CNC and then LinuxCNC. After the program has started, you can shut it down and continue below.

3- Install Probe Basic requirements
On a terminal emulator run:

sudo apt install python-pyqt5 python-pyqt5.qtquick python-dbus.mainloop.pyqt5 python-pyqt5.qtopengl python-pyqt5.qsci python-pyqt5.qtmultimedia qml-module-qtquick-controls gstreamer1.0-plugins-bad libqt5multimedia5-plugins pyqt5-dev-tools python-dev python-wheel python-setuptools python-pip git python-pyqtgraph python-pyqt5.qtwebkit

4- Download ProbeBasicInstaller
Link on the github page is broken. Luckily I still had an old copy.
You can download it here: ProbeBasic-Installer-py2+3.g231c7ff.run

Click the link below to download the ProbeBasicInstaller file. Once downloaded, find in its destination folder and right click and select properties. Select the Permissions Tab in the window that appears and check the box for “Allow this file to run as a program”, see images below for reference. now double click the installer icon to begin the installation. Follow the installer instructions to install Probe Basic. Select all of the available items during initial installation. after installation probe basic should show up in the linuxcnc launch screen and you can select to create a desktop icon for it by selecting the check box to do so at the bottom of the page.

Congratulations! You now should be able to launch Probe basic!

Tools:

• Rufus 3.20 Portable
• Linuxcnc 2.8.4 buster ISO

Materials: USB stick 8 or 16GB

CNC controllers require understanding of the exact length of tools in order to compensate for any tool length differences between milling cutters.

In this article, I go over the various style of tool length sensors available. Evaluating aspects such as accuracy, versatility, and cost.

Lower cost mechanical tool setter

The lower-cost mechanical tool setter such as the HLTNC CNC tool length sensor which I reviewed here is the most popular method of tool length measurement for DIY hobby or semi-pro CNC machines.

There are various models available on Aliexpress and at other sources of these lower cost mechanical tool setters. Internally they are all constructed similar. There is a plunger where the end mill presses down and internally there is a switch that gets contacted when the plunger is moved down by a certain distance.

The repeatability of this style of tool setter has been shown and tested to be within +-0.01mm – 10um. For most DIY, hobby, and semi-pro CNC machining applications this is suitable.

However you will face some challenges with irregular shaped milling tools such is index-facemills or bigger tools that exceed the size of the plunger.

In addition this style of mechanical tool setter does not allow you to measure the tool width.

The elecrtical connection of this type of tool length sensor is quite easy. It with either have an NC or NO type switch internally which allows you to connect it to your cnc controller board such as an UCCNC or Mach 3 breakout board.

Non-contact tool setter

Non contact tool setting system often recognizable the U shape is one of the most common methods for automatic tool length measurement for industrial machines.

These non-contact tool setter work by sending a small laser beam from the sending fork to the receiver fork on the other side.

Due to its non-mechanical nature of it, the accuracy and repeatability of it tool length measurement is generally around 1 – 2 um for the more affordable models such as the Sick WF2. On the higher range of the spectrum, the Renishaw NC4+ achieves a repeatability specification of +-0.5um for smaller tools and +-0.75um for larger tools

An additional benefit of this type of non-contact tool length sensor is that it allows irregularly shaped tools such as big insert-based face-mills to be accurately measured. This can often be a challenge when using a contact-based tool setter.

In addition to that you can do width measurement of an milling tool. This is especially beneficial to capture catastrophic damage to a milling tool or to verify that the physical tool matches the tool size as set in the cnc controller such as linuxcnc or UCCNC.

This width measurement is usually less accurate than length measurement. One can generally expect about 20 – 50 um measurement accuracy using a non-contact

Endmills and other milling tools are often not completely flat on the bottom face due to cutting edges etc. To measure the longest point of the endmill accurately this kind of non-contact tool length sensor requires the spindle to turn (~1000 rpm) while measuring the lowest point of the milling tool.

On the second hand market such non-contact tool setters are available from just 10$.

Popular term for this on european ebay is “Gabellichtschranke” which translates to “Fork light barrier” – one example of this is the Balluff BGL000A which you can often find new or used for 20 – 40$

Premium – mechanical tool setter

In comparison to lower-cost mechanical tool setters that are often used in the DIY CNC community, there is also a premium style available that can achieve repeatability numbers comparable to or better than non-contact tool setters.

Renishaw OTS 3D touch trigger tool setter is one of such premium mechanical tool setters.

While listed as a mechanical tool setter in this article, internally it is just like the non-contact tool setter optically based to achieve better stability and accuracy numbers.

Brand new the Renishaw OTS 3D tool setter costs approximately 2000$ but used these can be found for about 500 – 1000 $ on places like ebay.

The Renishaw OTS 3D tool setter lits a repeatability specification of 1.00 um.

There are a few copies of this design on aliexpress but they are still quite pricey at 1000+ $. At that price point, I would advise to look at second-hand options in the west.

Conclusion

In this article, the various kinds of tool length setters are described with each having their pro and cons. For most hobbies and DIY use, a lower cost mechanical tool setter will be sufficient.

Looking for more versatility and better accuracy? have a look at (second hand) non-contact tool setters.

Are you a job-shop that is running VMC all day long, with coolant etc – for you the premium 3D mechanical tool setters for a brand such as Renishaw might be the right option.

Introduction

While looking for a Integrated AC servo drive solution for my MightyMill build, I was tipped by the machine builder DamenCNC to look at the Delta ASDA-M series of AC servo drives for my gantry based cnc router.

In this article I’ll share some of the highlights that this product has to offer and my opinions regarding it.

What is the ASD-M AC servo drive?

The ASDA-M series goes beyond the typical servo drive. It includes 3-axis servo drives in one frame to support real-time data exchange among three axes without any time delay and provides 3-axis synchronous motion control with performance better than comparable servo drives. Such as a diy solution with ASDA-A3 and ASDA-A2 drives.

This synchronous features set allows a new gantry control function for synchronous control that is precisely adapted to pure rigid mechanical systems.

What features does the ASD-M have?

The main features of the Ac servo drive ASDA-M are as follows:

• 3 servo drives integrated in one unit
• 3 external encoder inputs for full closed loop operation (i.e. linear glass scales)
• Multi axis synchronised motion
• Expansion capabilities
• Step/dir input
• See Datasheet for all the information
• …

Benefits of such a drive for a (DIY) CNC router application?

One of the most challenging items I came across with my Mightymill build was Y-axis (gantry) synchronisation during high speed machining (HSM). In more DIY style of routers this is often something that is overlooked.

But when your goal is to develop a semi-professional system these become aspects that need to be mitigated.

When you are doing high speed machining (HSM) with feed rates of 10000mm/s and up AND require accurate parts gantry synchronisation becomes a serious problem.

The ASDA-M servo drives solves this solution by integrating multi axis synchronisation of Position, Speed and torque with a 16kHz loop speed. In addition it is basically 3 ASD-A2-0721-M drives integrated into one. This makes the overall installation much easier and compact

Alternative solution? ASD-A2 or ASD A3 drive

Delta offers other servo drives which have the gantry synchronisation function.

The options that I found comes down to basically tying two ASD-A2 drives together or two ASD-A3 drives.

This makes overall wiring and control more difficult. In addition to the lower slower sync rate between axis versus the 16 kHz that the ASD-M offers.

And in case with the A3 drives could require additional communication or hosting over a protocol such as Ethercat. Which makes it more difficult to integrate with DIY style cnc controllers such as UCCNC, Eding CNC or Acorn CNC.

How much does it cost?

Pricing of these ASDA drives varies a lot by country and from which dealer you get it from. I have seen western webshop prices of around 1500 USD while the Taiwan-based prices start from 700 USD for the ASD-M-0721-M model

There are various (second hand?) drives on ebay hovering around 600 USD mark. For the ASDA-M drive that I bought I paid on the lower end of the above range (Taiwan direct) ex taxes ex shipping ofcourse.

For basically three ASD-A2 drives in one I find that a good deal. Especially when looking at the extra features it offers.

How does it work-out in practice?

I’m currently waiting on my ASD-0721-M drives and ECMA-C10604RS AC servo motors to ship from Taiwan. When they arrive I will start mounting them on my machine and share the process with you. Make sure you subscribe to our e-mail newsletter. So you don’t miss these updates.

What is polymer concrete?

Polymer concrete is the composite material made by fully replacing the cement binders of conventional cement concrete with polymer binders or liquid resins, and is a kind of concrete-polymer composite. Replacing these binders allows new and interesting properties which excel above regular cement based concrete.

How is it made?

Polymer concrete (PC) consists of an aggregate mixed with a monomer or resin that is subsequently polymerized in place. The techniques used for mixing and placement are similar to those used for portland cement concrete. After curing, a high strength (greater than 10,000 psi), durable material is produced.

There are various commercial products available in pre-mixed form. Each having their own speciality such as a good basis for molding machine components – Nanodur or for filling hollow areas in machine beds to provide better vibration dampening properties – Durfill .

Increasing vibration dampening properties of machine frames

Polymer concretes – especially UHPC mixes are an increasingly popular material for DIY and professional CNC machines. It allows you to upgrade an steel tube or aluminium tube based machine frame and add beneficial dampening properties to it.

How much improvement can you expect?

Below is an illustration showing los coefficient of materials (dampening performance) vs young’s modulus (stiffness).

Epoxy granite for example is approximately 3-5 times better in dampening vs an empty steel tube. But there are other polymer concretes that exceed the improvement by 50 times. source: Durfill – Fraunhofer -IWU .

As can be seen in the table and image above there is a big range of performance depending on which filling is used in the machine frame construction.

My personal experiments

I wanted the best performance for my up and coming cnc build so I decided to fill my aluminium extrusion with Durfill.

Containing the concrete

I filled the bottom of my aluminium extrusion with garden sand. With some light compressing it made a good and easily removable spacer. Which afterwards could just be removed by spraying it with water.

Filling the aluminium extrusion

Durfill is easy to mix. Just add 2,3 liters of water to 25kg of pre-mixed UHPC – mix it and pour it into the aluminium extrusion. It is self compacting, removes the bubbles by itself. Therefor it is very easy to use.

Finished product

Conclusion

Polymer concrete is an awesome material and filler for diy and professional CNC machines. Albeit a little bit expensive, it is easy to use and has very beneficial properties for machine frames and other applications.

Its practical use is immediately noticeable when knocking on an empty aluminium extrusion and one that has been filled with a uhpc product such as durfill. It does not ring which an empty extrusion or tube would do. When you knock on it it sounds like a dead knock such on a big piece of granite or concrete wall.