I hope someone is old enough to remember the old Herbert. Mine is 55 years old. First of all I am a beginner, so much of this is pretty basic. I am trying to make a bush to allow a 3 sheaf V belt pulley with a large keyed internal diameter of about 1.75 inches fit securely on a 1.25 shaft. This from a big saw bench that I am restoring. I have turned down a piece of solid bar to the right OD but I have run into lots of difficulties. The chuck does not hold the piece, which is about 5 inches long, securely. I turned it down using the chuck and a dead centre and even though cutting off was difficult and I ended up sawing it off and cleaning up the end, it is more or less the right external size. When I put this in the chuck to try and bore it, it is not held very securely or accurately.
The chuck, which is about 9 inches in diameter, seems very stiff to tighten. I cannot see how this dismantles, as I think it is worn or dirty inside. I removed the jaws and I can see the scroll, which looks OK - although one jaw is a bit tight. It is the chuck key drive sockets that seem to have the problem though and there are some grub screws that seem to hold these in, but when I removed the grub screws there are some pins or something underneath that don't seem to want to come out. I would like to dismantle the whole thing as I think that this is where the problem lies. Although I have removed all the cap screws on the back face it will not come apart. (?)
I do have another chuck that would fit, but although it looks as if it is in much bigger and better condition, the jaws will only move about
1/4 of an inch. They do move freely though. This looks as if it is by design as there are two little arrows on each jaw that indicate the extent of this movement. Adjustment of the holding capacity is by moving the holding lugs on 3 serrated edges on the jaws. Is this normal, as it will be a big pain only being able to adjust the holding capacity on the scroll, by 1/4 inch, (is there a scroll for this 1/4 inch only?) It will mean having to remove and accurately line up the lugs again each time something else is needed in the chuck.So I am a bit stuck on the chuck problem. Also one of the 3 holding studs on the worn chuck has a damaged thread. I can probably get this out and replace it, but I would rather use the other one. Again, I have removed all the cap screws holding this better one together and although the drive squares are held in by little covers that came off easily I still cannot get the big one apart either.
On a different subject, the cross slide drive turns several times before the tool holder actually moves and I cannot see what to do about this. Once it has taken the slack it goes the right number of thousands though, so I can live with it and it is such an old machine that I doubt if it will ever be tight again. It should be better than this though.
The capstan does not come close enough to the chuck to allow drilling or reaming from any of the capstan tool holders. I tried to drill out the centre of my bush roughly but the only drills I have that are stout enough to do it are too short to reach and one rather long one that reaches wanders about and although I have drilled through it ready to bore it out to the required diameter in my pillar drill, I am not very happy with this.
If anyone has any comments or suggestion as to what I can do about these problems, I would be very glad to hear them.
Thanks and regards, George.