DeWALT DW089 Calibration
The DeWALT DW089 is a multiline laser featuring; horizontal and dual vertical lines at 90 degrees. This model is self-levelling utilising a pendulum mechanism, see my post on self-levelling technologies HERE
Most self-levelling line and dot lasers with a pendulum levelling mechanism operate in pretty much the same way with a pendulum suspended within gravity. Calibration is achieved by re-weighting the pendulum usually with the use of two grub screws, one for each axis of movement, X and Y. The majority of laser levels of this type often have easy access to these two grub screws, making calibration pretty straight forward. DeWALT and Bosch, in particular, do not make calibration easy at all. With the majority of other brands of laser levels of this type they have two dust covers covering the access to the calibration screws, see images below.
With many DeWALT and Bosch models, you need to disassemble the laser to get at these screws making calibration at best difficult and at worst just not economic to do.
Another thing the DeWALT line lasers do differently to the majority is that they generally have no pendulum lock. This means that during transit the pendulum is bouncing around in the laser all the time. Personally, I would much prefer to have a pendulum lock as most other manufacturers do. Saying this, I must say to balance the conversation, that the DeWALT’s are built pretty well.
There is one other little anomaly DeWALT have which I do not have the answer to but one of you out there might. On a number of their line laser models, they claim that they are a class 2 product but then states that its output is 1.5mW. Now as far as my knowledge of going through various standards class 2 only cover less than 1mW above this and below 5mW is a class 3. Also after working with laser levels for many, many years I know when I get a flash in the eye from a laser greater than class 2. The DeWALT DW089 feels far more than a regular class 2. Anyway, that’s just my observation.
Calibration Procedure DeWALT DW089
Back to calibrating the Dewalt DW089. As previously indicated we need to partially disassemble the laser to get to the calibration grub screws. At this point, I’ll again make a point of saying if you do not now to what height to calibrate to set to, do not go any further. Send your laser to a laser level calibration specialist. Also, The Laser Level Review takes no liability for any damage you may cause your laser if you decide to continue following these instructions.
For the purpose of this example, I’m assuming that the laser diodes are all working correctly. Also, the geometry between the horizontal and vertical lines is intact and correct. I’m also assuming that there is no inconstancy in the bearings. If the bearings for the levelling mechanism are damaged, worn or have grit in them then achieving a reliable calibration will not be possible. Checking bearing based pendulum self-levelling mechanisms is a post on its own and something I’ll try and cover in the next few weeks. So assuming geometry and bearings are good then the principle is if we get the horizontal line calibrated correctly. Also, check the two vertical lines are consistent with each other and plumb is good then the laser level is calibrated.
The first thing we need to do is remove the cast metal housing on the front of the laser level. This is done by removing the four tech screws (sorry not sure of the size) see image below.
Next, you need to remove the four screws on the base of the laser. Note two of them are within the battery compartment.
You can now prise apart the base section from the top section carefully. A cable connects the two half, you may be able to work with the cable attached. However, detaching it may make the calibration procedure for you easier. One axis grub screw is reasonably easy to get at, that’s the left to right one, the X-axis. The other axis is located at the back of the unit. It is much harder to get at with a tech screwdriver this is the Y-axis. I’ve known some calibration places actually drill a hole in the plastic casing to get at it. This for me is a little extreme. I have found using a hex, Alun key of the right size can do the job if you do not have access to a 90-degree tech screw key. See images below.
The tricky bit
The rest of the process is a bit of an art. Turn the grub screws for each axis in order to shift the weight of the pendulum in the required direction. The grub screws may be stiff to start with. This is due to a locking substance used when it was manufactured. Once you have moved the grub screws replace the bottom casing. Make sure the batteries are installed and check your horizontal heights for both axis. Make a mental note of how far the horizontal line has moved. Also if was in the correct direction for both axis. Remove the base again and make more adjustments, you may need to repeat this a number of times. If this was one of the other laser levels with easy access to calibration screws you would not need to spend all this time disassembling and reassembling before each check.
Once you are confident that everything is calibrated then you can put it all back together. Note if the calibration grub screws move a little too freely then you may need to use some screw locking compound.
and that’s about it, as always if this was helpful to you please consider a donation. If you have anything to add please feel free to comment at the bottom of this page or by email.