In Bob's test bar thread he and I had a brief exchange about Albrecht drill chucks. I think they are one of the best out there and one of the things I like about them is that they are practically bullet proof - all the parts except for one are hardened and ground. If something does break there are parts available and once you know the tricks they are not hard to repair.
He asked if I could put something up about overhauling them so as I had a boat anchor of a chuck arriving I have.
The chuck was covered in rust as it it had been sitting in a damp cupboard (Normally I find these in the US, but this came from the UK. It could have been in a damp cupboard I suppose). It had been subjected to some abuse. The tips of the jaws are dinged up as can be seen. These burrs may have to be stoned out as when the chuck is worked it hangs just there.
First remove the arbor. Wedges or straight brute force may have to be applied here. Don't open the jaws and try driving a punch down the guts as Albrechts have a moving part in there and you won't move the arbor but you could break the chuck. This arbor is a bit of a worry as the end is burred over. Mounting it in a sleeve in the lathe (Yes, not the most accurate I know), I got 4 thou of run out. It seems a common problem and it is probably fair to say that most times when the TIR on an Albrecht seems large it could well be a bent arbor.
With the arbor out, the first thing to do is take the collar off the back of the chuck. This is held in place with a single screw, so loosen the screw and then tap a screwdriver in the gap to expand the collar slightly (this is the only non hardened part). The collar will just lift off.
Then, holding the chuck in the vice just below the knurled bit, use a chain wrench or similar to loosen what is referred to as the "hood". The join is just under the knurl (second picture), here just cracked open. Be careful here as the hood and the section underneath are thin walled. Too much pressure will deform them (hence the chain wrench instead of stilsons or a pipe wrench.
That's it really - how to open an Albrecht. There are small loose parts inside so don't do anything more than loosen until you have seen part two.
Michael
He asked if I could put something up about overhauling them so as I had a boat anchor of a chuck arriving I have.
The chuck was covered in rust as it it had been sitting in a damp cupboard (Normally I find these in the US, but this came from the UK. It could have been in a damp cupboard I suppose). It had been subjected to some abuse. The tips of the jaws are dinged up as can be seen. These burrs may have to be stoned out as when the chuck is worked it hangs just there.
First remove the arbor. Wedges or straight brute force may have to be applied here. Don't open the jaws and try driving a punch down the guts as Albrechts have a moving part in there and you won't move the arbor but you could break the chuck. This arbor is a bit of a worry as the end is burred over. Mounting it in a sleeve in the lathe (Yes, not the most accurate I know), I got 4 thou of run out. It seems a common problem and it is probably fair to say that most times when the TIR on an Albrecht seems large it could well be a bent arbor.
With the arbor out, the first thing to do is take the collar off the back of the chuck. This is held in place with a single screw, so loosen the screw and then tap a screwdriver in the gap to expand the collar slightly (this is the only non hardened part). The collar will just lift off.
Then, holding the chuck in the vice just below the knurled bit, use a chain wrench or similar to loosen what is referred to as the "hood". The join is just under the knurl (second picture), here just cracked open. Be careful here as the hood and the section underneath are thin walled. Too much pressure will deform them (hence the chain wrench instead of stilsons or a pipe wrench.
That's it really - how to open an Albrecht. There are small loose parts inside so don't do anything more than loosen until you have seen part two.
Michael
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