Maintenance Guide

This page is missing:

Software updates.

Hardware upgrades.

Troubleshooting known problems. In progress

Repairing common failures. In progress

Tested replacement parts

Stating frequency

Maintenance Guide¶

Required skills and resources¶

Maintaining your pipetting bot doesn't require superhuman skills, just a little time and dedication. Here's what you'll need:

Time to spare

Set aside some time to clean, lubricate, etc. Think of it as a small investment that keeps your bot running smoothly.

Replacement parts

Keep a stock of commonly replaced parts like belts, rods, and nuts. This minimizes time-loss.

A commitment to care

Following the recommendations on this page is your key to success. No fancy skills needed, just a desire to see your pipetting bot thrive!

Post-assembly setup¶

Note: This section is missing a proper tutorial. This section takes a couple hours.

Software updates¶

Note: This section is missing a proper tutorial.

To-Do: commands for updating are similar to the ones for installation.

Add links to relevant contents: use Mainsail, connect through SSH and use git pull, etc.

Hardware upgrades¶

Note: This section is missing a proper tutorial.

Lubrication¶

Lubrication is an important step in maintaining Pipettin Bots, as it helps to:

Reduce friction
Prevent wear and tear
Dissipate heat
Protect against corrosion

In addition to these general benefits, lubrication can also have specific benefits for different parts of the Pipettin Bot. Lubrication, for instance, can help to improve the accuracy of pipettes and reduce noise levels.

Some parts, such as the threaded rod and wheels, are lubricated at the factory. However, other parts, such as the lead screws, bearings, gears, and belts, need to be lubricated regularly by the user.

Apply a thin coat of lubricant to the moving parts of the Pipettin Bot.

Be careful not to over-lubricate, as this can attract dirt and dust.

Tip

Clean the parts before lubricating them. This will help to remove any dirt or debris that could interfere with the lubricant.

Here are some specific lubricants that you can use:

White lithium grease (such as WD-40) is a good general-purpose lubricant for the moving parts of the Pipettin Bot. It is relatively inexpensive and easy to find.
Silicone grease is a good choice for lubricating the lead screws and bearings, as it is resistant to moisture and dust.
Synthetic oil can be used to lubricate the gears and belts. It is important to use a synthetic oil that is specifically designed for use with precision machinery. Also recommended for tools maintenance.

Note

If you are changing between different types of lubricant, we recommend cleaning away the original lubricant with isopropyl alcohol first.

Instructions to lubricate CNC machines: https://www.youtube.com/watch?v=Yn6FFd1ry9g

Belt tension¶

Almost all parts of Pipettin Bot have a hole for adjusting the position of the motor until it is tight, at least the z-carriage. For the xy-carriage, the motor position is adjusted manually.

Pipettin Bot achieves motion using a system of pulleys and belts as explained here. For optimal operation it is important that the belt tension is maintained at the correct level. Excessive belt tension will contribute to premature bearing wear. Insufficient belt tension can also lead to reduced pipetting accuracies.

Since belts stretch over time, it it recommended that the user occasionally measures the belt tension and adjust as necessary. This can be done with any device that allows you to measure audible frequency in hertz or even manually.

Here are some tips for adjusting belt tension:

Be careful not to overtighten the belt, as this can cause it to break.
If the belt is too loose, it will slip and cause the Pipettin Bot to malfunction.
It is a good idea to check the belt tension regularly, especially if you use the Pipettin Bot frequently.

Instructions to adjust belt tension manually¶

Adjust X-Axis belt tension manually¶

To adjust X-Axis belt tension just pull the belt as tight as possible ensuring that it is tensioned. Then, use a zip tie to secure the belt in place. Make sure that the belt tooth profiles are aligned to ensure tightness. It should look like this

Adjust Y-Axis belt tension manually¶

To adjust the Y-axis belt tension, we designed a system that lives in the 20x20 V profiles of the Z-Axis. This system is adjusted with screws as shown below.

To adjust the Y-axis belt tension first loosen the screws, tension the belt and then tighten the screws.

Adjust Z-Axis belt tension manually¶

To adjust Z-Axis belt tension first you new to loosen the four screws shown at the image below. Then, move the motor towards the direction of the green arrow to tighten the belt and once the belt is tensioned, tighten the screws.

Info

To tighten the belt, move the motor in the direction of the green arrow. To loosen the belt, move the motor in the direction of the red arrow.

Instructions to adjust belt tension using an app¶

Follow the instructions here: https://www.youtube.com/watch?v=tg9Co_1MyZo

Vref adjustment¶

Visit the Software & Electronics Setup to access to the Vref adjustment steps.

Pipetting Bots parts: maintenance¶

Many technical documentation entries have specific maintenance information:

Testing¶

Note: This section is missing a proper tutorial.

Test replacement parts¶

Note: This section is missing a proper tutorial.

Maintenance frequency¶

Note: This section is missing a proper tutorial.

Troubleshooting known problems¶

Overheating¶

Stepper motors generate heat as they operate, and if the heat is not properly dissipated, it can cause the motor to overheat. This can be cause by:

Irregular maintenance regim: If the CNC machine is not regularly cleaned and cleared of dirt, it can lead to overheating. This is because the dirt can clog the channels within the system, preventing the machine from properly cooling itself.
Running the machine at the highest RPM for a prolonged period: As the RPM increases, so does the friction between the moving parts of the machine. This friction generates heat, which can lead to overheating.
Variations in environmental temperatures: If the CNC machine is placed in a workspace that is not properly ventilated, it can lead to overheating. This is because the high ambient temperature can cause the machine to overheat.

For reference: temperatures of 150°C or above are considered deteriorating for nearly every CNC machine and its tools.

How to Fix: Keep you machine maintained and clean. Check the manufacturer's recommendations for the maximum RPM and operating time of your CNC machine. Place your machine in a ventilated workspace.

Incompatible Power Supply¶

CNC machines are highly complex in their building, and they may display specific issues with their functioning due to power supply problems. This is why CNC machines must operate at appropriate power supply settings. Sometimes, the CNC machine tool’s display or different parts may not work due to issues with the power supply

How to Fix: To resolve this issue, the machine operator should ensure that the correct power and voltage supply is used for the power and supply input. If the power or voltage is low or no one, try disconnecting output wires when the power is off. An elementary system examination for power issues can be performed. A stable power supply is required and is the basis for trouble free operations with any CNC machine.

Programming errors¶

It’s safe to say that CNC machines are sophisticated pieces of machinery that require absolutely precise execution commands. A single G or M-code error in a CNC file instantly results in a result that does not comply with technical requirements.

How to Fix: To resolve these errors, it is important for new operators to be adequately trained in the different ways in which CNC machines can be programmed. Comprehensive user manuals and training, motion sequencing, and operation of the machine should be provided to new operators by the machine suppliers or experienced operators on the shop floor. On the other hand, rapid prototyping serves the purpose of making impeccable CNC files with zero errors. If there are some related issues, the approach to rapid prototyping should be revised.

Poor maintenance of the CNC machine tools¶

Modern machines with multiple constantly moving mechanical parts, CNC Machine Tools, need to be regularly cleaned and maintained to keep them running optimally.Failure to clear away dirt, material and other debris could result in a build-up which over time can result in inaccuracies in machining or even machine failures.

How to Fix: It is crucial for machine operators to follow a detailed maintenance regime for the machine tools in use. This should be done to ensure that operations continue to be smooth and uninterrupted.

Machine vibration issues¶

The efficiency of some machines can be measured by how well it vibrates. However, with CNC machines, vibrations are not recommended. If a CNC machine vibrates while performing a task, it could potentially reduce the lifespan of that tool. It may also affect its durability and long-term functionality.

How to Fix: To identify the machine's vibration issues, the machine operator must diagnose whether the chatter comes from the workpiece or the tool itself. They can try adjusting the machine's RPM using a balanced tool holder, so that the frequencies of the machining process will not resonate with the material frequency.

Repairing common mechanical failures¶

All you actually need to know, as seen at R-bloggers.

Pipettin Bot common failures¶

Note: This section is missing a proper tutorial.

To-Do: Do tests on Pipettin Bot to learn more about its common failures.

Tool Changer Problems¶

Occasionally, you may face challenges with the tool changer in your CNC Machine Tool.

How to Fix: This could be resolved by learning every step of the tool changing process, and troubleshooting it by diagnosing what went wrong. Check that the baseplate, the pipette, and toolparking (tool holder) are working properly and smoothly. Or examine the swivelling and mechanical pipette action to see that they work properly. Do also keep the tool changer and tool holders clean of chips and coolant.