1. Incorrect track setup
   
2. Flooring
   
3. Loose wheels
   
4. Wind
   
5. Loose belt
   
6. Image properties
   

Incorrect Track Setup

The tracks should always be set up under the following parameters:

1. The transition points where 2 long beams meet are completely flush; you should be able to run your fingers over them and not feel any points where one beam is higher/lower than the other.
   
2. The bolts do not need to be tightened down as far as they will go. They only need to be tightened as much as needed to keep the long beam secured to the cross beam and keep the long beams flush with each other
   
3. The nuts on the feet are tightened both above and below. The feet are entirely touching the floor. You should be able to grab the long threaded part and be unable to move it around.
   
4. The cross beams should be touching the ground except for in cases where minor leveling is needed using the feet. The level should generally not exceed more than 1/2 inch. Both sides of a crossbeam should never be off the ground, level using only one side. Employ scaffolding or shims in cases where the crossbeam would need to be 1/2 inch or more off the ground
   
5. The tracks should generally be 7-10 inches from the wall, measuring at the start of the long beams. They must be parallel to the wall throughout. The distance from the wall is determined based on the printhead having 3 inches of movement both forward and backward from the surface.
   
6. The tracks must be clean of dust and debris.
   
7. You should not hear any noise indicating that the tracks are moving as the weight of the printer moves across them. You can run the printer over the entire length of the tracks prior to printing to test this
   

Flooring

Despite the leveling properties of the tracks, sometimes the flooring is the cause of the banding. This is due to the weight of the printer. Check your flooring and employ a shim of some kind underneath your tracks if you believe that the floor may be shifting. Some types of flooring that can cause banding include:

1. Plush carpet that stops the tracks from being able to properly level
   
2. Vinyl that is not completely flat against the floor underneath it. This also happens with newly laid flooring that has not had time to adjust and flatten out
   
3. Tile with grout, where a foot is between 2 tiles. The grout may stop the foot from being completely perpendicular to the floor
   

Loose Wheels

We recommend tightening the wheels before every print job. The wheels tend to loosen from transport and general use. Use the 4mm Allen key included in your Customer Care kit to tighten them.

1. Remove the black caps at the center of the wheel. These caps are for aesthetic purposes only and can be removed permanently for easy access, if you wish. If you’re unable to remove the caps easily, a small precision flathead screwdriver can be used for leverage between the wheel and cap. 
   
2. Use your 4mm Allen key and tighten the bolt to the left. The bolts are counter-threaded.
   
3. Do this each time after you transport your printer and before each print job. 
   

Wind

When printing outside, wind may cause the machine to sway as it prints. While you cannot eliminate the wind completely, there are a few techniques you can employ.

1. In the TWP operation software, go to Printer information in the top left corner. Find Machine Settings and set your printhead Speed to 1 or 2. Slowing the speed will lessen the amount the printer sways.
   
2. Set up something to block the wind, this can be as simple as parking your car in the direction the wind is coming from, or as complex as building a temporary structure around your job site.
   

Loose Belt

The green and white Y axis belt must always have adequate tension on it. If you believe that your belt is not tightened enough, please remove do the following:

1. Remove the 4mm bolts on the white block that holds one end of the belt to the other. 
   
2. Loosen the 3mm bolts that hold the belt to the block and adjust the position of the belt between the teeth of the block. You will likely only need to adjust by 1 or 2 teeth.
   
3. Tighten the 3mm bolts once again, then use the 4mm bolts to secure the belt structure to the printer once again. Tip: tightening the belt in the teeth of the block to the point where only the very ends of the 4mm screws touch the lower block will oftentimes provide the perfect amount of tension once tightened completely.
   

Image Properties

If your banding is not eliminated after checking each of these environmental factors, the issue may be in the image itself. Take note of whether the banding is consistent each time you print. 

1. Do you find a band of the exact same width happening at the same location in an image every time? If so, it is likely the image itself causing the issue. To reduce this, we recommend rasterizing the image and adding a Spot Channel. We have instructional documentation on how to do both of these things in our Dropbox and Customer Portal. 
   
2. If the banding is still showing at that point, we recommend using a different image.
   

Also note that there is a difference between banding and pixelated vertical lines from a low resolution image. Banding looks like a lightened line across the entire length of the image from top to bottom, whereas vertical lines from a low quality image tend to only be apparent in darker or more pixelated parts of an image. If you are unsure whether you are experiencing banding or pixelated lines, please contact Support with the original image you used to create your .prn as well as a picture of your printed result.