There are dips and rises in the RPM of the router I have in my router table, it's an 8mm Parkside router, so a very cheap model. It also screams a lot, I mean it's really loud, so I think the bearings it came with need replacing, probably bad quality ones from factory. But does any of that explain the inconsistent speed? The router has built in speed control. I need to open it, but to find the time... Might as well throw the ball around and see if anything comes of it I figure.
Router speed is inconsistent
- Thread starter DennisCA
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MMUK
Established Member
Sounds like the stator is failing.
I don't know, I only hear the change but I can't estimate how much the speed changes. Not a lot I would guess. The workshop is a freestanding garage with pretty beefy electrics, but I did cut & rejoin the power cable when mounting it in the board, perhaps this is the cause. I could do a better job of it I think.
Eric The Viking
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Try, very gently, to alter the speed control whilst it's running. You don't need a collet (nor nut, nor cutter) in it for this test.
If there's any spot where it hesitates as you alter the speed, it's probably the speed control itself. They're usually carbon-track potentiometers ("pots"). Better quality ones are sealed and might even be conductive plastic instead, but in most cases, especially if it's a thumbwheel rather than a knob, it's just a bit of pencil lead wiped round a circular track of compressed carbon. The change in resistance as it goes round results in a change of speed (via some electronics!).
Carbon pots hate dampness and have a tendency for the track itself to crumble, especially if left for a long time with the wiper in one position. If that's what's happened, you'll find it when you try the test above.
There are no easy fixes for this apart from replacing the part. Don't under any circumstances attempt to lubricate the pot with WD40 or any sort of spray lubricant or oil (even if it says it's suitable for electrical contacts). Any organic lubricant will dissolve the track surface and make matters a lot worse, if it doesn't cause complete failure of the component.
There is one possible patch-up that sometimes works (but usually isn't permanent), and it depends on getting easy access to the pot's track, and the track being of suitable carbon material: you can rub a soft artist's pencil - 4B or 6B, nothing harder - over the spot on the track that's failing. You may not be able to see the area with the naked eye, so you might have to note how far round the problem spot is, then find it again once you've dismantled the router to get at the track. Obviously, don't go near the thing with a leaded pencil when it's connected to the mains!
The graphite from the pencil is supposed to both fill the hole in the track and lubricate the wiper a bit (blow off any excess). I must admit though that I've not had much success with this in the past.
To prevent the problem occurring in the first place, always park the speed control at either it's maximum or minimum setting. One will be better than t'other. If you look at the circuit board you can usually see the connections to the pot: only one end of the track is normally actually connected to anything. Park the wiper at the other end (the one not connected). That way if there is any damage caused, it's not affecting the working part of the track. Regrettably, the Trend/DeWalt/CMT T10/T11 series have the speed controls as a module, and you can't get at the individual components -- yours might be the same, in which case you just have to guess. It will still be better than just leaving it set somewhere in the middle, especially as the electronics age.
Aside: I do this with the old analogue audio mixers I have. They can have hundreds of pots, and I stored them with all the knobs (usually) at maximum. It works: I have one mixer that's about 30 years old, with no noisy pots at all, not even the faders (which are the same idea but move in a straight line). It's a nuisance to have to set everything whenever I start to use it, but a lot less hassle than having to source spares from that long ago!
Router speed control circuits can fail in other ways too, for example, if there's a rotational sensor, the pulse-generating magnet can physically come loose or drop off the shaft (happened to my Trend T11 and I'm not alone in that!), and other electronic components can fail too. Beyond the obvious mechanical things ("what's this plastic ring loose in the case" Oh, it's a magnet!"), you need someone good at electronics to diagnose and fix it, or to swap out the whole module.
Given it's Parkhouse, it might be worth taking it back to Lidl, as they have a good returns policy.
Probably way too much info, but it might be useful at some point.
Regards,
E.
PS: Forgot to say - I have a Power Pro router from B+Q with very similar symptoms. It's just about usable so it was cleaned and shoved in its box in the attic in case. I ought really to either fix it or chuck it out...
If there's any spot where it hesitates as you alter the speed, it's probably the speed control itself. They're usually carbon-track potentiometers ("pots"). Better quality ones are sealed and might even be conductive plastic instead, but in most cases, especially if it's a thumbwheel rather than a knob, it's just a bit of pencil lead wiped round a circular track of compressed carbon. The change in resistance as it goes round results in a change of speed (via some electronics!).
Carbon pots hate dampness and have a tendency for the track itself to crumble, especially if left for a long time with the wiper in one position. If that's what's happened, you'll find it when you try the test above.
There are no easy fixes for this apart from replacing the part. Don't under any circumstances attempt to lubricate the pot with WD40 or any sort of spray lubricant or oil (even if it says it's suitable for electrical contacts). Any organic lubricant will dissolve the track surface and make matters a lot worse, if it doesn't cause complete failure of the component.
There is one possible patch-up that sometimes works (but usually isn't permanent), and it depends on getting easy access to the pot's track, and the track being of suitable carbon material: you can rub a soft artist's pencil - 4B or 6B, nothing harder - over the spot on the track that's failing. You may not be able to see the area with the naked eye, so you might have to note how far round the problem spot is, then find it again once you've dismantled the router to get at the track. Obviously, don't go near the thing with a leaded pencil when it's connected to the mains!
The graphite from the pencil is supposed to both fill the hole in the track and lubricate the wiper a bit (blow off any excess). I must admit though that I've not had much success with this in the past.
To prevent the problem occurring in the first place, always park the speed control at either it's maximum or minimum setting. One will be better than t'other. If you look at the circuit board you can usually see the connections to the pot: only one end of the track is normally actually connected to anything. Park the wiper at the other end (the one not connected). That way if there is any damage caused, it's not affecting the working part of the track. Regrettably, the Trend/DeWalt/CMT T10/T11 series have the speed controls as a module, and you can't get at the individual components -- yours might be the same, in which case you just have to guess. It will still be better than just leaving it set somewhere in the middle, especially as the electronics age.
Aside: I do this with the old analogue audio mixers I have. They can have hundreds of pots, and I stored them with all the knobs (usually) at maximum. It works: I have one mixer that's about 30 years old, with no noisy pots at all, not even the faders (which are the same idea but move in a straight line). It's a nuisance to have to set everything whenever I start to use it, but a lot less hassle than having to source spares from that long ago!
Router speed control circuits can fail in other ways too, for example, if there's a rotational sensor, the pulse-generating magnet can physically come loose or drop off the shaft (happened to my Trend T11 and I'm not alone in that!), and other electronic components can fail too. Beyond the obvious mechanical things ("what's this plastic ring loose in the case" Oh, it's a magnet!"), you need someone good at electronics to diagnose and fix it, or to swap out the whole module.
Given it's Parkhouse, it might be worth taking it back to Lidl, as they have a good returns policy.
Probably way too much info, but it might be useful at some point.
Regards,
E.
PS: Forgot to say - I have a Power Pro router from B+Q with very similar symptoms. It's just about usable so it was cleaned and shoved in its box in the attic in case. I ought really to either fix it or chuck it out...
