HELP do i need to buy a new router ???

[hunggaur]

hi folks i currently have a 1/2 hitachi MV12 router which has been fanastic however over the last few weeks it has developed a problem.

when you turn the router on it does not start. however if you spin the spindle with the router turned on it will kick in and start and runs fine.

When going it does sound a little spluttery on occasions but i don't know if this is connect to not starting problem.

I have taken the brushes out and checked them and there about 8 to 10 mm thick.

any advise would be welcomed

many thanks

jon

 

[Eric The Viking]

Two questions:

1. is it variable speed?
2. could it have got cold and/or damp recently?

If 'yes' to both, it's probably the varispeed pot (control). They're almost always made of compressed graphite. They don't like damp and they don't like being left on the same setting for long periods. It might improve if you work the speed adjuster to and fro a bit (gently - don't get too rough with it), and you might find it starts well at a different speed.

If not 'yes' to both, I defer to m'learned colleagues...

E.

PS: you might get the controller board repaired fairly cheaply - the components aren't expensive if you can find someone to do it.

 

[Racers]

Hi,

Could be a bad winding on the rotor which you should be able to buy as a spare part.

Pete

 

[hunggaur]

many thansk for the advice i will try playing with the speed setting as it has been left set on number 6 for a while. it has also been left in my work shop which has been cold. Is it worth sending off to get repaired if so to whom or should i just buy a new one. jon

 

[Digit]

The 'spluttering' and failure to start sounds as though the armature has had it. Do you have a multimeter?

Roy.

 

[9fingers]

Or poor brush pressure/sticky brush boxes
8-10mm does not sound that long for a meaty router brush.

Bob

 

[mailee]

I have two of these and the first one developed the same problem, I tried checking it with a meter and came to the conclusion it was the electronic speed control. They are about £80! I bought another and thought I would keep the old one for spares or if a cheap one came up for spare to repair it.

 

[EssexChris]

It might be worth trying a new set of brushes for only a few pounds.
Have just changed a set on the same machine, as it was starting to make strange sound on start up. Brushes were down to about 12mm. Now sounds fine again.


Chris.

 

[Digit]

Hardly worth buying new brushes if the com's had it, if Jon has access to a meter the com is easy enough to check, and pricey to replace.

Roy.

 

[Rob Platt]

I have two of these and the first one developed the same problem, I tried checking it with a meter and came to the conclusion it was the electronic speed control. They are about £80! I bought another and thought I would keep the old one for spares or if a cheap one came up for spare to repair it.

Likewise

I will add that i also took mine to the local specialist power tool repair shop and they confirmed exactly as above price was dearer. Seems to be an issue with this model. But it had well paid for itself many times over and it didnt stop me buying another of what must have been a contender for the best router around at the time.
all the best
rob

 

[Eric The Viking]

If the controller is potted (totally encased in plastic or rubber), it's hard/impossible to repair because you have to dig the circuit board out first. If it's just the anti-vibration goo (white or black, usually), that often comes off by pulling with needle-nosed pliers (usually). Then you can get to the components. They shouldn't be at all expensive individually, with the possible exception of the actual speed control potentiometer (might be hard to obtain). The individual components are cheap enough that you can simply test by substitution - try the pot and the capacitors first, and any obviously burned resistors (it can be hard to see the value after they've had a good scorching!).

Doing all this would mean you're happy poking about in mains equipment (you'd have to test it!). I would say 'don't go near it' if you're not. But it shouldn't be £80 of time for someone competent to change a few components. Is there any sort of electronics repair shop near you? A vacuum cleaner shop might do it.

E. (who hates the waste of throwing away repairable things).

 

[hunggaur]

many thanks for all the advise. i can get access to a multi meter but how/what do i need to test ???

i do have a dealer near me "paskins" so i could drop it in there if i have no joy.

i will try the bushes to see what happens

if i have to get a replacment which model should i look at ????

many thanks

jon

 

[Digit]

Jon, if you had brought the router to me I would have noted two comments, stuttering and damp. What happens is this. As the brushes wear the inside is coated with carbon.
Now carbon is both a lubricant and a semi-conductor, dry. When damp it becomes sticky so that the brushes jamb. This causes the stutter.
Ignoring it wrecks the com, if you're lucky it won't have got that far, but even if replacing the brushes works the machine needs stripping and all the dust cleaning out and very probably the com cleaning. This is what a pro would do and what you would be paying for.
And you can DIY.
Borrow a meter, remove the brushes then the 4 screws that hold the base on and withdraw the armature, then me an Bob can take you through from there.

Roy.

 

[hunggaur]

Jon, if you had brought the router to me I would have noted two comments, stuttering and damp. What happens is this. As the brushes wear the inside is coated with carbon.
Now carbon is both a lubricant and a semi-conductor, dry. When damp it becomes sticky so that the brushes jamb. This causes the stutter.
Ignoring it wrecks the com, if you're lucky it won't have got that far, but even if replacing the brushes works the machine needs stripping and all the dust cleaning out and very probably the com cleaning. This is what a pro would do and what you would be paying for.
And you can DIY.
Borrow a meter, remove the brushes then the 4 screws that hold the base on and withdraw the armature, then me an Bob can take you through from there.

Roy.

many many thansk for that Roy i will order some new brushes next week and send you a Pm when i have everything ready.

kind regards

jon

 

[Digit]

Frankly Jon I wouldn't buy the brushes till you've checked the com.

Roy.

 

[mailee]

I am afraid the electronics on these are 'potted' It is completely sealed in plastic so no good trying to replace components. I have a friend who could do this for me if they were accessible. I have to say though that I have been more than satisfied with the router and it has done a few years service without any problems...hence the reason I bought another.

 

[Digit]

I've got the earlier model Hitachi which has no speed control. It's permanently mounted in a table with a remote speed control.

Roy.

 

[hunggaur]

Frankly Jon I wouldn't buy the brushes till you've checked the com.

Roy.

many thanks for that roy. just to let you know i have ordered a multimeter and will PM you when it arrives if thats OK

 

[Digit]

Fine, no problem. Do you know how to dismantle the router?

Roy.

 

[hunggaur]

No any advice would be greatfully received

many thanks

jon