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Guide to mechanical adjustments and maintenance

This guide was originally created by Donna, moderator of the official Sculpfun user group, with some additions made by me.

Laser imaging is so precise and has so many variables that it becomes difficult to achieve good results regardless of what brand of laser you own. Sculpfun produces very capable lasers at great prices that can achieve the results you’re looking for as long as you take the time to make sure everything is adjusted correctly before you start.

Important

The following adjustments apply to all models and should be checked regularly. Especially, the lens needs to be cleaned regularly. Depending on your usage, this might be daily!

Perpendicular frame

Make sure the frame is set up straight and that the frame must be aligned at right angles. After assembly, you can check this by moving the x-gantry completely to the front or back. Both ends should reach the front or back profile bar at the same time.

Tilt test

The tilt test is the best way to evaluate if adjustments to any of the three belts are required. Here is a great video by Mike [Admin of the Sculpfun FB group] demonstrating the tilt test and the perpendicular frame. If the tilt test is not successful, you should definitely check the belt tension and eccentric nuts!

Belt tension

Above all else, this can cause you the most problems if not set correctly. Too tight and the lasers’ movement is restricted, too loose and banding or wavy lines will occur. To adjust the tension, undo the nut (pictured below) with the tool provided and pull the belt to the desired strength before re-tightening the nut. This applies to all three belts.

Wheels / eccentric nut

Secondly, underneath each of the three carriages you will find a wheel that needs to just touch the underside of the frame, these are adjusted by turning the eccentric nut. To see if these need adjusting, firstly gently rock each carriage from side to side to see if there’s any movement. Especially in the one holding the laser head itself also run your finger over the wheel to check if there’s friction. If there’s movement in the carriage or the wheel runs freely, then you will need to raise the lower wheel to touch the frame and stabilize the carriage. Be careful not to over-tighten so that the wheel movement is restricted. The same holds for the opposite situation, where the wheel is already too tight. In this case, you commonly notice some kind of clicking sound / bumby feel if you move the slide manually. Then the wheels are too tight.

To adjust the eccentric nut, do the following…

Loosen the nut (A) and turn the centric nut (B) a quarter at a time with the provided spanner to raise or lower the wheel. Once the wheel just touches the underside of the frame (until there is no play anymore, then stop immediately), re-tighten nut (A) and repeat the tilt test.

Linear rail (S10)

The S10 laser has a linear guide for the x-axis instead of rollers. No mechanical adjustments can be made here, besides lubrication, which should be done regularly (as with all ball bearings). A video that is often recommended for this is the following:

This video shows how to integrate the linear rail upgrade kit to S6 / S9 lasers (in German, but you can activate subtitles).

Belt positioning

As stated above, a good result depends on so many variables that the slightest thing not set correctly can affect your finished image. Make sure all three belts run central to the toothed gear, a slight deviation either to the left or the right can cause the belt edge to rub against the side of the gear, causing extra friction and possible banding. To adjust this, do the following…

Take the provided Allen key and loosen the nut pictured. Gently slide the gear so that the belt is central, then re-tighten. You should check these grub screws anyway, since they have been loose at some users.

Pulleys / gears

As stated above, many users reported that the pulleys have not been tightened enough to the motors axes. This leads to slips in movement. Check the small grub screws if they are sitting tight.

Dirt

Always make sure EVERYTHING is clean before each burn. That not only includes the laser lens itself but also the rails and gear teeth which over time collects dirt from the wheels, soot from wood and paint from tiles.

To clean any part of the machine, use a cleaning wipe, I use spectacle lens wipes for the frame and lens cleaning spray plus soft cotton buds for the lens and gears. This will be a regular action you will need to take after every few times of use.

To clean the lens, people commonly use Isopropanol or any other alcohol and cotton swaps. You have to remove the protective cover by loosening the grub screws holding it or in case you have an air assist nozzle, you need to remove that as well. In newer versions, there is a metal simple air assist nozzle mounted above the protective shield, you can remove this as well by loosening the according grub screws. It is hard to tell at which time span you should do that, it heavily depends on your usage level. I recommend to check often in the beginning and after some time you have enough experience on when to clean it. If you have a great air assist nozzle, you might nearly never need to clean it. See the extra section and video below.

And that’s it. Of course, you will need to ensure you use a high-quality image in the first place and that the processing is applied correctly in LightBurn or whatever laser program you are using. Other guides will deal with that part of the process, by following all the steps above will give you a great chance of achieving decent results with your Sculpfun laser.

Connector fixing

It happens quite often that users have problems with the plug connection on the laser module. This then manifests itself either in a total failure of the module or (much more difficult to detect) by a loose contact and strange results when lasering (only one part is lasered, lines, dots, etc. are missing in between). It is important to provide strain relief at the connector of the laser module! This can be done in different ways. The laser comes with small cable ties that can be used for this purpose. There is no right or wrong here, the essential thing is that the cable on the connector of the laser module does not move when the module is moved (or pushed) back and forth. Some 3D-printed mounts include holes to attach the cables. This also partly applies to the hose of the Air Assist, check this as well.

Cleaning of the lens

This is one of the most important points to keep in mind. If you don’t use a perfectly tuned Air Assist, it is very likely that dirt particles will collect on the lens over time. This is a major hazard to the laser! When the dirt on the lens heats up from the laser beam, the lens will go blind or even crack! This is the most common cause of defective lasers and declining laser performance. It is better to check once more often than once too little. Depending on use, the interval may vary, but for frequent use, this should be done every few hours of operation. Cleaning can be done with a cotton swab and cleaning agents such as alcohol, isopropanol, or specifically designed optics cleaners. The following video from Mike shows how it works. This is analogous for all lasers in the Sculpfun line. Some lasers have a small lens protector built in (as seen in the video), but this can be removed. The S9 modules usually also have a conical air-assist-light metal cylinder built in, which can also be removed by loosening the grub screws.

Videos of the cleaning procedure:

S6 / S6 Pro with brass cylinder:

Video explaining the cleaning process

S9:

Cleaning the lens at the S9 module

S10:

Cleaning the lens at the S10 laser module

Removing the lens at the S9 module:

Removing the lens

Adjustment of Firmware parameters

Often instabilities come from wrong parameters in the firmware. I recommend adjusting the following values (see the page about firmware on how to change parameters). Especially, the acceleration should be adjusted as shown here!

ParameterValueExplanation
$1105000 mm/minMax speed for x-axis
$1115000 mm/minMax speed for y-axis
$120250 mm/s²Max acceleration for x-axis
$121250 mm/s²Max acceleration for y-axis
Recommended settings for acceleration values

Calibration of the axes

If, despite everything, inaccuracies still occur, the axes can be calibrated even more precisely with a LightBurn function. To achieve this, draw a rectangle (I would recommend at least 100 × 100 mm) and have it lasered. Now you can measure the actual distances and enter them in the following LightBurn wizard (Edit ⇾ Machine settings). As an example, I measured 102 mm on the x-axis. The wizard outputs the new value for the steps/mm of the x-axis ($100) and can also save it directly in the firmware. Thereafter, you let the rectangle be lasered again and check if the measurements are exactly right.