[Bill Zoucha]

Bought a very nice used Woodtek Router table with porter cable router, trying to cut slots but every time I run a pass and then test again it has got lower, the bit is tight, but it seems the up and down mechinism is moving, very frustrating, can't use if I can't depend on it staying at the height I SET IT.

 

[jw2170]

Welcome to the forum, Bill. I wonder if there is a problem with router lift. Is it a plunge router or fixed base?

 

[old55]

Welcome to the forum Bill.

 

[Marco]

If you have a router lift check that first to see if it is dropping. If that's not it check that the PC router height adjustment is locked.

 

[PhilBa]

With a used machine you have to assume that it hasn't been well taken care of. Tighten every screw, bolt, nut. Look for wear and damage. Unplug every electrical connector, look for corrosion/damage, clean and reinstall. That may not be the cause of the problem but you need to do it anyway.

Now, test the machine by running an air cut - tell it Z zero is well above the spoilboard, make a note of where Z zero is and run your GCode program. If it it finishes with Z zero in the same place, then run a real cut test. If that fails then there are several possibilities:

• Z acceleration is too high, losing steps.
• Z feed rate is too high, losing steps
• stepper current is too low, losing steps
• Chuck/collet is not tight enough or damaged and bit is slipping. Bit too small?

 

[Alphonse53]

Bought a very nice used Woodtek Router table with porter cable router, trying to cut slots but every time I run a pass and then test again it has got lower, the bit is tight, but it seems the up and down mechinism is moving, very frustrating, can't use if I can't depend on it staying at the height I SET IT.

What model PC router are we talking about?
Is it in a lift or mounted directly underneath the table?

 

[five20]

I have the same lift and the same problem. What happens is the vibration causes the mechanism to slowly lower the router on lifts that have seen a lot of use. Woodtek must have recognized the problem because the newer models have a lock that is operated from above the table. The simplest way to stop the movement is to thread a stop nut on to one of the elevator screws. I 3-D printed a plastic hand wheel with a 14 - 1.25 thread. It adds time to the set up but definitely prevents the movement. Of course you could buy a nut to fit yours and make a wooden hand wheel. I only engage it on long cuts where bit height is critical.