Changing chuck on a Makita

[keiron99]

I have a Makita MXT drill (cordless combi).

Unfortunately, though it's apparently in most respects a decent bit of kit, the chuck is absolute garbage. Even with the easiest of tasks, the bits work loose. On hammer action, it works loose even just running it in the air!

So I've decided to replace the chuck. Even the cheapo drills in B&Q have what seem good designs. I've seen Rohm and Jacobs chucks which apparently "lock" tight with a clicking mechanism, and also usefully have a free spinning outer shell on the chuck, Ii guess so you can put your hand on it to guide the drill while in action. I'd like to hear of recommendations and where I might purchase (ebay seems obvious!)

Second, I don't seem to be able to remove my existing chuck. I've removed the bolt that runs down the middle of it. However, after that I'm stuck. I've put a big allen key in the chuck and whacked it in all directions and can't get it to budge. Any help with that would be welcome too.

Thanks.

[R]

When I did my Makita Small Tools training course a while ago, the recommended way was to drill through the side plastic behind the chuck with a 3.2mm drill approx halfway through the diameter of the chuck mount at 90 degrees. Insert an Allen key through the hole to loc the chuck and put another (8mm) Allen key in the chuck then strike smartly anti-clockwise to release the chuck. The screw sometimes found in the centre is left hand, but you have removed it. There *might* be threadlocking compound on the threads, so warming carefully the chuck will assist in release.

[keiron99]

Thanks. I'm not quite clear on the reason for drilling the hole, and to be honest I'm very reluctant to do that! I have tried clamping a big allen key in the chuck, and striking it. Indeed, I've probably done about half a dozen full rotations in a counter clockwise direction, but it's still not loose.

[R]

You don't mention a specific model.

The reason for the hole is to provide an aperture to put the 3 mm Allen key through into the hole in the side of the shaft to lock it. Even in low gear (If chooseable) all you will succeed in doing is spinning the shaft.

If the 2 shell casings are removable (Usually several screws around the case) you might try stripping the gearing out and holding in a vice using aluminium or copper vice jaws (Flattened plumbing pipe will do) and then try to undo the chuck.

[auctions]

If the drill's not too old, get it checked under the warranty - the chuck in mine is absolutely fine. The bits work loose if I catch the side of the chuck against something occasionally, but otherwise, as long as I tighten it properly to start with, it's fine.

A

[Sylvain VAN DER WALDE]

I suppose that you're relying solely on the braking force generated by the geared down drill armature. That may not be enough. I would follow the advice given to you: drill that hole (it may not have to go as deep as directed). Then you'll have a _more positive_ resistance when you're attempting to unscrew that chuck.

Sylvain.

[keiron99]

Sorry, I am *really* dumb, I really have no idea what is going on inside the case. Let me get this right: I drill a hole in the black plastic section between the drill itself and the chuck? (this is the rotating piece which sets the torque on my 8414D)? Then I stick an allen key into it, and what does it latch onto when inside? (Can't pretend drilling a hole in the case appeals to much...)

Another question which may convince you I am out of my depth here: when I'm trying to release the chuck, in which direction am I trying to turn it as I look at the drill with it pointing at me?

[John Rumm]

Sounds like it is shagged certainly. The previous generation of those drills used ratchet action Rhom chucks with a free spinning cap which really were first rate. Some of the later ones are not as good IMHO (although not as bad as yours - so something is not right with it)

Have you looked at the exploded diagram for your drill? It may help:

[Andy Wade]

Also bear in mind the experience of a. n. other contributor:

[John Rumm]

That is a good point and often overlooked. I am often surprised how cost effective it can be using the official service route!

[Lurch]

On Mon, 30 Apr 2007 13:50:33 +0100, John Rumm mused:

I've sent some of my drills into oficial service centres rather than back to Makita directly and have had a replacement rear half and motor for a 14.4V cordless and a service and few new parts on a 110V SDS for about 30 quid. Hardly worth getting your fingers greased up.

[Ian White]

It's a kind of selective blindness, a perfectly normal symptom of being DIY Positive. Usually harmless but sometimes expensive.

[keiron99]

Hmmm...does make you think. Thing is, money's tight and I've removed the chuck from another old drill that will do. The one on the Makita however is absolutely jammed solid. I rang Makita and have done as they say: put in low gear, put in drill setting, pu in allen key and smack anti clockwise. But it just won't budge!

[keiron99]

Well, I finally got the bugger loose, and in fact installed a Rohm Extra RV as you describe, John. This one here:

The ratcheting locking mechanism works an absolute treat, and the spinning cap makes holding the drill so much easier (for me at least). Brilliant design.

[John Rumm]

Yup, that looks like the one on mine. Handy to know you can order them separately.

(the other change they made to the latest Makita combis was to add an extra skirt round the base of the chuck - closing up the gap between the back of the chuck and the front of the gearbox. Oddly I find that reduces the grip you can get on the chuck because you can no longer get hold of the rear edge of it)