Tired of loose V wheel eccentrics?

A while ago, after finding V wheel eccentrics loose for about the 3rd time, I designed these little adjustable locks.

It’s a pain to drill and tap the holes for the lock screws, but once that’s done, you shouldn’t have to mess with the eccentrics ever again.

Here’s the link to the model:


Warning! Don’t trust the feeds and speeds.



Get yourself some Mr Beaver’s Nuts. He has massive eccentric nuts!


“Mr. Beavers massive eccentric nuts” I would like to nominate that as the comment of the year.


I second that. Call me immature, but that had me rolling with laughter. Thank you!


FYI: My kit came with blue Loctite, which I use when I assembled the machine, and the nuts have never loosened and 3+ years


I’m immature too but it sounds like Mr Beaver is not😉


Did you apply the Loctite after adjusting the nuts?

During assembly…so I guess that was technically before…still easy to adjust…since it is only blue Loctite…but they NEVER loosen. So feel free to install some anytime.


Thanks! I had assumed that you’d need to use the penetrating (“permanent”) type to be effective after the nuts were installed and adjusted!

After 8 hours of cutting on the final cut out the wheels came loose and ruined the whole thing!
If I could have picked up my Shapeoko and thrown it out the door I would have, just a bit too heavy. I will take a look at your idea and give it some thought. Thanks for the idea.


I’m not 100% sure what you mean by “the wheels came loose.” Are you implying that the eccentric nuts loosened? If this is the reason, I bought an early model, one where you had to assemble every nut and bolt, and it came with a tube of blue thread locker (Loctite). To this day (3.75 years later) I have never had a wheel loosen due to the nut…wear…yes, but that is very gradual and does not cause any harm.

Let me know what the root cause of your wheels (all of them??) loosening up?


I’ve been cutting for a year straight and mine have not come loose.

Which ones exactly where?

While I have not had any loosen, I have noticed that due to the right had threads, adjusting the eccentrics on some locations, will cause some nuts to tighten…and the other half to LOOSEN <----- This is where the Loctite helps.

So over time, during normal maintenance, cleaning and adjusting, it is likely that some of these eccentrics will loosen (if they do not have Loctite).

Due to the threading, once one has the bolt/nut tightened, best practice is to then use a hex wrench in unison with the wrench used to adjust and to turn the bolt/nut as an assembly so that one maintains the tension.

As cool as the eccentric nuts are, from an engineering standpoint the original eccentric spacers which required the addition of a nut and suitable washers were arguably better.

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FYI There are several grades of thread locking compounds. I would not use permanent because it is meant as permanent and the size of these bolts and nuts you would easily strip them before the thread locking compound would give. Additionally the only real way to get permanent loose is with heat and that is not very compatible with a Shapeoko. Locktite makes a “Removeable” thread locker that is just sticky enough to keep the bolt/nut from loosening but not so locked that you cannot get it loose. Remember in the future the V wheels may need to be replaced. So do not use permanent unless you really mean to never adjust the bolt/nut again.

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I use 242/243 blue Loctite, haven’t had anything come loose in quite some time. As was mentioned I tighten everything with both an Allen wrench and an open/box end wrench fully, with eccentrics away from the rails, then only turn the eccentrics in the (clockwise) tightening direction when adjusting. If I go too tight when adjusting I tighten from the Allen head side to loosen the v wheel on the rails. Make sure the fixed wheels (non-eccentric type) are loctited and fully secured before even messing with the eccentrics. If you decide to go with a heavier loctite such as 270 green, you can use the tip of a decent wattage soldering iron to get heat right where you need it to loosen(I don’t suggest anything more than the blue 242/243 though). Last tip, put the bolts fully through the bearings, then either apply loctite to the exposed threads only, or inside the eccentrics themselves (I put a drop of loctite on a paper plate, then dip a toothpick in to use as a brush). Most of the common loctite brand threadlocking liquids are anaerobic, they will only cure in the absence of air, so don’t apply to the bolts, wait to dry, then stuff them through the bearings, you’re just putting loctite in your bearings (not great).



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