Thread: Chucks & Camlocks

Hi Ray,
I get the click as well, it's from the plunger going into the detent when it comes around to the open position.

It will be interesting to see Bryan's camlocks.

Dave

Dave, leaning on a 300mm lever sounds like a lot of grunt to me too, but what do I know? If you say there's no damage after years of use I guess it's fine.

Below is a pic of one of my cams. The groove goes all around, but is only full width for half a turn. No detents.

Also attached is a pic of my 4 jaw. The jaw slots are all broken away at the top, every one. What manner of bastardry could cause this sort of damage? I thought about machining grooves and trying to fit some key steel or something but there's not enough wall thickness in the casting. I think it is an ex chuck.

I just went and checked the T handle and it's 240mm (120 either side) T handle not 300mm as I thought. The T handle part on it came with the the lathe but I made up an extended version to get up over the headstock so I don't knock my knuckles.It is fixed in position so it can't be slid to extend it, but originally in the factory shaft it could be ,which made it a pain to use as it would slip out when putting it down.


I have never seen any camlocks like that, but I suppose the Chinese make them the easy way, where yours would be made by milling as well, instead of just turning.
I am not sure why or how your 4 jaw got like that, not something you see.

Dave

I edited the other post and sorry about misleading you. I will make sure I measure next time before posting. I find the way the tolerances are with my tapers, it takes a little bit to get the two faces seated together. The 3 and 4 jaw supplied with the lathe where a nice fit, so I just use them as guides for the rest of them.

I will have to make some camlocks for my D1-4 adapter like Stuart built, so I might try to copy yours and see what they are like and if they are better.

Dave

Hi Bryan,
I was just thinking, if they are still out could you run the verniers over them and post up the dimensions? If I was to have a O ring it would probably break into the side wall of the square drive so yours must be bigger, but I like that idea of having one.
If you have already put them back in, not to worry.

Dave

Hi Bryan,
I take from the way the groove is machined that the grub screw for the camloc comes in from the front (face the chuck sits against)?

The only guess I have for the damage to the chuck is gripping short work pieces way to tight. That may also explain the dings I think can see closer to the other end of the slot.

I made a key like Daves, the pretty colors dont show up well in the picture

Stuart

Dave, dimensions attached. Don't quote me on the cutaway though - bit hard to measure (I mean the big radius). You're right, there's not much meat between the corners of the socket and the o-ring groove - about .85 mm by my reckoning. I don't know how much good the o-ring does. I guess it keeps any lubricant in, but it doesn't keep chips out. For that you'd need one on the other end. Not much room though. Maybe a really thin one?

Stuart, yes but not the actual seating face, the vertical face inside the taper, closest to the bore. Which appears to be a clearance face.

Over tightening is highly likely as the guy had extra long handles on everything. I've started cutting some of them down.

Stuart, that T handle came up good and I like the grub screw in the end.

Bryan, Thanks for taking the time to do that, much appreciated. I will be able to measure the radius of my camlocks, or I could be lazy and ask Stuart as I am sure he worked it out for his.
I think the purpose of the O ring would be for friction to keep it in place when it's undone, where our Chinese ones have the spring and plunger.
As for the guy using long handles it saves on muscle power if you have an injury or are getting old where you don't have the force. Even though he has been using the long handles do you see any wear on them caused from it? Like I said earlier mine don't have any wear, and I think it would take an awful lot of pressure to do any damage, if you could damage them that is as they are really hard.

Dave

No probs Dave. Is yours D1-5? If not the dimensions will be different anyway I think. I can say for sure the cutout provides generous clearance (1-2 mm on dia) for the fixed pin to slot in.

The long handle comment was relating to the damaged chuck. There's no damage on my camlocks. A little wear is all.

Speaking of friction, I think it was you Dave who said they hold by friction. Does that mean they shouldn't be lubricated? I have conflicting instincts.

Thanks Dave, Its pretty shades of blue and brown. One funny thing that came up when making it was it turns out the chuck and keys are 9.5mmSQ, the cam locs are 10.4mmSQ. never seemed to matter much but nicer now the new key is the right size. Its long enough I can turn it past the gear levers in any position.

Bryan, I lubricate mine. Haven't really got my head around what stops them coming undone.

Stuart

Mine is D1-4, but those measurements will come in handy as I will mix them with mine, I was just after a general idea of your sizes.

I lightly oil mine with some oil on my finger every now and again, the pressure from the camlock wouldn't be bothered from a bit of oil. If anything it will help if slide better to get it tighter.
Once you start using them you will see what we mean, they lock up real tight. As I said earlier who ever invented them did a great job, as it's a good system.

Dave

This is a 10" 4 jaw I bought from fleabay to replace my broken 12".




The chuck is actually not in bad nick. Despite looking a bit beaten up, there's very little wear on the jaws. By a stroke of luck it has a taper that matches my D1-5 spindle, but instead of 6 camlock pins it just has 4 bolt holes on the exact same diameter.



From the details on this page I think it must be an A2: Lathe Spindle Nose Fittings. I decided to try and convert it to direct mount camlock. I had a spare set of pins, and measurements suggested it should work. I would need to use two of the existing bolt holes. Luckily there was enough meat to do this.



I don't own a mill, but I do have a rotary table and a drill press. In this pic I have a centre in the drill chuck so I can locate it on one of the existing holes. The rotab does the rest.



Yes it's a little bit dodgy. Suffice it to say there were a few little problems to solve along the way. Fortunately the camlock system has reasonably generous tolerances on the pins. It's the taper that does all the locating. Anyway, I seem to have pulled it off.



It's a handy size and suits the machine well. Much easier to wrestle than the 12". Direct mount keeps the weight down too.

I still have a bit more to do. More on that later. Meanwhile, comparing it with the factory camlock on the left, can anyone spot my stupid mistake? I mean a geometric error.

HI Bryan,
Looks good. As for whats wrong with it, my guess is the PCD of the pins shouldnt be the same as the PCD for the adjustment bolts.(though I can't work out why that would be)

Stuart

Give that man a cigar. Yes I blithely assumed they were on the same PCD. Because why wouldn't they be? Well I don't know why but they aren't. And that means the cutouts on the pins don't align correctly with the cams. So that's one problem I have to solve.