Variable speed power drill

[bbg]

It isn't directly boaty, but it is "practical".

I have a several-years-old Black & Decker variable speed corded hammer drill. At least it used to be variable speed. Now I have to depress the trigger all the way before anything happens. Sometimes I get a "click" and full speed, sometimes I get nothing.

Is this the kind of problem I can sort myself? Is it worth getting B&D to sort it (it is no longer under warranty and it will cost me about £13 in postage just to send it and get it back, in addition to the repairs)? Or should I just get a new one (not cheap)?

I think the model is KR850RE or something like that. In any event it says it is 850 watts, FWIW.

 

[duncan]

sounds like the rheostat - should be a cheap part and relatively simple diy if you can get it

 

[savageseadog]

I'd try and get a "spares or repair" one off ebay

 

[Poignard]

If you do a Google search of "black & decker spares" you'll find plenty of suppliers.

 

[gjgm]

as an option, try screwfix or toolstation. For hammer drilling, give up on these rotary and get a cheap FERM SDS. Ok you ll need to get some sds bits too, but for hammer drilling this will whack through anything up to 4inch concrete. Just be a tad careful on walls, or you might be in the next room b4 you know it. About £30/35.
Then for normal drilling get a 24V cordless, 2 batteries and a 1h charger. Again Ferm is pretty good,maybe £30-35.
Taken me decades to realise this, but this combination is far better than the usual DIY B/d-Bosch solution. FAAAAAAR better!
Just in case the £2 spare isnt availbale on ebay!

 

[Hugh Foulis]

Another vote for this option. I have the ferm SDS hammer drill from screwfix and its a quantum leap forward compared to an ordinary rotary hammer drill. Similarly with a higher voltage cordless and 2 batteries, (this time from Wickes but around £30) much more versatile and convenient than a corded drill.

Best Regards
HF

 

[bbg]

For those who suggested that this is an inexpensive part to replace - thanks. I have done some searches and found this website. But I don't see a "rheostat" listed. Could it be called something else? When I opened the drill there was a small box inside the body of the drill, just above the trigger - is this what I should be trying to replace? Thanks for the further help.

As for SDS - thanks for the options. I will look into these SDS things, but being in Switzerland I might not be able to find them. I would also prefer to repair this for a good price if I can. I already have the cordless drills and screwdrivers, but very occasionally I would like a corded hammer drill. It has served me well until now and I can't imagine I will need anything better in the future.

 

[ThreeSummers]

I'd say its part no 105 in that drawing...

 

[duncan]

me too looks like the switch is integral

 

[2Tizwoz]

I'm not familiar with the particular model but on some B&D models, if not all, the 'switch' incorporates the variable speed electronics and I have had an older drill fitted with variable speed when the fixed speed switch failed.

 

[richardandtracy]

I suggest you put it to one side & get an Argos 'Challenge' reversible hammer drill. I got one last weekend for £6.49. The quality is poor, they are noisy, but Argos give a 1 year guarantee, and when it dies, you'll have a trigger to put into the B & D.

Regards

Richard.

 

[Cliveshep]

It's your trigger switch that's gone and the variable speed controller is integral with it.

 

[Engage]

You could spend some money and time fixing it then 3 days later something else goes. My recommendation is to go to Homebase which have some reasonably priced electrical tools and take out the extra cover. It is a no quibble cover. By their admission, 1 day before the extended warranty is up, smash it then get a spanking new one. Bargain. Fortunately I have never had to resort to such skulduggery but have enjoyed several replacements of cordless drills and lawn mowers.

 

[William_H]

I think you will find it is the rheostat (potentiometer) that is dicky. This is formed by a metal wiper contact moving around or along a carbon track with resistance. The further along the track the more or less resistance which then varies the voltage on the thyristor electronic switch which varies the power to the motor.
The first trick is to flood the movintg parts of the switch rheostat with CRC or WD40 or simillar contacy cleaner or water dispersant. (even fly spray) ecercise the control to get the WD right inbside.
It is very likely this will fix it.

No it is doubtfull if a commercial repair would be viable.

If you find the control box you may be able to bypass the electronics to give just on off full power or worst case on all the time it is pluged in. You may be able to cope with that. Maybe use it with an externsion cord with switch. good luck olewill