drill chuck no longer cinches

[jdfnnl]

I have a great 20v dewalt drill (DCD790) that has developed a problem holding onto smooth shank drill bits. First I thought of roughing the surface of the bits and inside of the chuck with sandpaper, but then thought about how I have been disappointed with the feel of the chuck when tightening. I would usually hear a series of clicks and a more gradual tightening of the jaws, but now it really only has one, maybe two clicks and the absence of that satisfying cinching response. On a couple of occasions, I have tried oiling and working the jaws in and out similar to what this video recommends, though admittedly I probably fell short on this sort of maintenance. I would like to know methods for restoring life to the chuck or if at this point the proper course would be a replacement of the chuck.

 

 

[paulengr]

Keyless chucks wear out. Replace.

Most of the Dewalt ones are made by Rohm. Their web site lists chucks by brand because they make them for everybody. I’m kind of partial to Jacobs but on power tools Rohm is the way to go. Changing is simple. The big trick is breaking the chuck loose off the shaft. There are several YouTube videos showing you how to use an Allen wrench and a vise.

[method]

If it's just a tightening issue you can just spray the inside with some WD40 or silicone spray. My metabo chucks do this every few years if they get heavy use and the lubricant makes them hold on and tighten like new.

[paulengr]

If it's just a tightening issue you can just spray the inside with some WD40 or silicone spray. My metabo chucks do this every few years if they get heavy use and the lubricant makes them hold on and tighten like new.

WD40 is solvent, not lube. It evaporates leaving no grease or oil behind. There are spray lubes but the problem is wearing of the friction surfaces in a well worn chuck. Mine gets every day use so I wear them out.

[jdfnnl]

Think I've tried lubing this chuck a couple times, probably wd40 then triflow or the like. But if people are saying chucks simply wear out in one way or another, either jaws that become too smooth or also in this case, a lack of that satisfying tightening/cinching action, then I suppose a replacement is necessarily called for. It seemed a bit challenging going through the manufacturers site, but with a search of "dewalt dcd790 replacement chuck," I found this Rohm on amazon that looks fairly stout. Thought I would see if anyone had any opinions on this or any other specific recommendations. $50 has me wonder whether a deal on a new drill or used of decent condition would be more cost effective ..

 

I took the old chuck off to get a look at what make of chuck came stock and how much of an upgrade this replacement would be. Nothing comes up with a search of the number on the back, but maybe someone has an idea?

 

 

 

[paulengr]

Rohm. That is who Dewalt uses. Same with Makita. Milwaukee uses another one sometimes and they suck but Rohm makes one for them too.

Unfortunately it’s a fact of life that keyless chucks are crap. Rohm makes the best out there. If there was a better one I’d buy it. As you said at $50 each it’s cheaper than a new drill but I’d like to get more life out of them. The old keyed chucks last as long as the tool.

[Tyson1987]

I  have had the same problem with my dewalt drill until i stumbled across how to use keyless chucks properly (incase your in the same position) 

 

when you tighten the chuck all the way up, loosen it off just one click. This actually locks a keyless chuck in properly and stops the drill bits from spinning. Then when removing drill bit just tighten back up one click again before loosening chuck.

 

May seem common knowledge to some but literally no one I've talked to since finding this out knew anything about it haha

 

good luck

[method]

On 6/11/2020 at 10:10 PM, paulengr said:

WD40 is solvent, not lube. It evaporates leaving no grease or oil behind. There are spray lubes but the problem is wearing of the friction surfaces in a well worn chuck. Mine gets every day use so I wear them out.

It has always worked for me. I wouldn't say WD40 evaporates like most solvents, it leaves behind a slight film but the plus is that it doesn't really make the jaws slip as I'd imagine lanolin spray or lithium spray might. Mind you, this is to stop the friction issue with the jaws not to help hold the bit in place, which in turn allows you to properly tighten the jaws if that makes sense.