Hey there! I’m installing a wasteboard. After starting to surface it, I’m seeing this odd pattern (pics attached) when using the Whiteside surfacing bit (6210). I’m assuming the issue has to do with machine setup (not the bit) because the left to right operation seems flush. But as you can see, the front to back and back to front operation is a bit odd.
The pattern is not odd. Your router is not square to the spoil board. You can use dial calipers, 123 setup blocks or a number of other ways to square your router to the spoilboard. Feel on the left side and if the high side of the ridges are on the left side you router needs to be rotated counter clockwise. If the high side is on the right then your router needs to be rotated clockwise. On the front and back if the high side of the ridges in in front then the top of the router needs to be shimmed outward. If the high side in on the back then the bottom of the router needs to be shimmed outward.
Make sure your v-wheels are all in adjustment and there are no mechanical issues moving the gantry from side to side and front back with the power off. Move in a slow motion because if you move too quickly the stepper motors are energized and you will feel and hear a strange noise.
After squaring (tramming) your router you need to surface the spoil board. If there are a whisper of t he lines then simply use a medium grip sand paper to smooth. try to get it as close to perfect as you can but at some point just use the sand paper.
What’s your stepover? If it’s 50%, then you can get oddities where the edges of every second pass just lines up. But yeah, tramming first, then reduce stepover, even just a little bit.
This problem is not with step over. Step over can leave tiny lines but what I see is classic that the router is not square with the machine.
Step over can be decreased and will decrease little lines left in slots and pockets. When you see the pattern in the pictures you just need to move the router to get it better aligned with the spoilboard. In the pics you can see that the left and right adjustment needs to be adjusted. The lines across the front and back might be acceptable but the problem may be worse than the pics show. Look at the spoilboard from different angles and with a raking light.
Thank you both for the help. I started by checking (and fixing) the leveling of the rails: that they are level to each other across, in the front and back, and level to themselves front to back. @gdon_2003 thanks for the tip on tramming the router–that seemed to resolve things the most. I used Winston’s video here (How to Tram Your Shapeoko - YouTube) to help with that. It’s not perfect, but I think close enough. I’ll run some things and see how they turn out.
@mhotchin, your comment reminded me to adjust the default step over from the template I got, so that it was less than 50%, so thank you for that!
