I’m experiencing enough run-out using my table mounted router that I get a rough surface finish when using a flush trimming bit. The table and lift are from Woodpeckers. The router motor is from Bora.
Using a dial indicator, there’s virtually no run-out when measured against the inside face of the router spindle (~0.001 of an inch). Using the manufacturer supplied ER collets, though, there’s more than 10x as much run-out when measured against a good router bit shank or bearing (~0.01 of an inch). I asked for replacement collets, but they are just as bad.
The pictures show my test set up and the maximum deviation.
Is this as simple as replacing the ER collets? They seem to range in price from about $5 for a cheap import to nearly $100 from McMaster. Does anyone have any suggestions or product recommendations?
Replies
I would be interested in seeing what you are referring to as a rough surface on your work piece.
As a woodworker I find it hard to believe a run out of 1/100 of an inch is causing significant issues.
I also am not sure your setup is consistent and capable of leading to the conclusions you are making.
It appears the angle of the gauge is different in the two tests. Any deviation in the angle of dial indicator will affect the measured runout.
You say the gauge is against the shaft of a bit, but the picture seems to indicate it's against a bearing, which could induce its own run out.
A more useful measurement would be the deviation of the cutting edge which is all that really matters. A bit that tracks perfectly true at the shaft would still not perform properly if the carbide cutting edges are not aligned properly.
Again I will say that I don't think the measured runout is significant and would be interested in seeing the problem you are seeing on the work piece and also the setup you are using to actually to make the cut. Your problem may lie elsewhere.
I would do two things.Obtain a short length of 1/2 and 1/4 drill rod and mike the "run out against these rods.No drill rod ? Use the shaft of drills for this task.Next,check how secure the router is in the table.Any movement could cause wobble and a rough serfice
What is an ER collet?
Your images are in HEIC format.
A rough result can definitely be from run out or vibration. I just put a Musclechuck on my Milwaukee 5625 mounted in a version 1 Woodpecker PRL. Possible runout and vibration caused by it were covered in the installation instructions. I bring this up just to state that I have recently looked closely at my table router and run out / vibration.
You state that replacement collets did not improve your problem. Was the collet nut also exchanged? The point being that a bad nut could be imparting misbehavior to the chuck itself.
Has the problem always been present or has it evolved? How old is the router?
At the Bora price point I would expect them to be pretty aggressive in being sure you are happy. Seems to be plenty of problems with premature bearing wear and vibration elimination issues reported on that motor.