[NJC]

Hello, Thanks to many of you, I have my machine running. Now I'm trying to actually cut something, LOL. I haven't been able to get my hands on any manuals yet so please bear with me, I'm a complete newbie.

First question, I purchased a new set of soft jaws and jaw nuts, when I clamp the chuck on a piece of round stock, the jaws don't sit square on the stock, they are tight at the chuck end of the jaw but at the outer end of the jaws, I see daylight, is this normal?

Next, I can get the spindle to move and change speeds while in the MDI mode with some codes you guys provided me but when I'm in manual mode, I can only get the X and Y axis's to move. I can't figure out how to get the spindle to spin, I want to just face off a piece of stock in manual mode to get the feel and try setting up my tooling.

Thanks,
Scott

[zanellan]

To get the spindle to spin using MDI mode, first go into MDI mode type in M3(OR M4) S???? (enter desired speed) press WRITE, then Cycle start. Now go into MANUAL mode (the spindle will now stop) and simply press SPINDLE CW or SPINDLE CCW (depending what M code you entered in MDI) The machine will remember the speed you entered and you can move the axis to part off the component/machine the part in MANUAL mode.

[littlerob]

As for the jaws I bore my jaws with an increasing taper from front to back for that reason, on the other hand a freind of mine simply uses very little chuck pressure "if the jaw is bored right you no need chuck pressure, Tai Le". Hope that helps. Robert

[NJC]

Thanks zanellan, that worked.

Robert, I'm not quite sure what you meen by boring the jaws with a taper, why wouldn't you bore them straight? I can't think of any reason why full contact wouldn't benefit in holding the work. If I'm on the wrong path here can you explain.

Thanks,
Scott

[littlerob]

Thanks zanellan, that worked.

Robert, I'm not quite sure what you meen by boring the jaws with a taper, why wouldn't you bore them straight? I can't think of any reason why full contact wouldn't benefit in holding the work. If I'm on the wrong path here can you explain.

Thanks,
Scott

Depending on chuck pressure and jaw length there will be less pressure on the part further from the chuck. Imagine holding a peice of say 6" sheet metal to a table, where you are holding it it is tight, away from it, it isn't. Same thing with chuck jaws, everything has some give. I probably should have been more specific, I taper the bore only about .001" per one inch, depending on chuck pressure, which gives me full contact. With that being said I am used to working with parts that are in excess of 200 pounds :tired: so I need alot of chuck pressure. but that is just my way. there are certainly alternative solutions. Robert

[NJC]

OK, that makes sense to me, I guess most chucks have some imperfections? Mine is out ALOT, I'm measuring .020 at the outer end of the jaws and tight at the inner end of course. I can see that the serrated mounts on the chuck are actually cocked, all three seem to be about equal. Is my chuck worn out? Is there any adjustment in the chuck to correct this? It's an 8" Buck chuck.

Thanks,
Scott

[littlerob]

.02 seems like alot to me, maybe not in six inch long jaws, but for a standard jaw length that sounds like alot. What weight and diameter are you chucking on? LB-15, not too long, not too heavy. (again coming from a guy who machines 200 LB parts). Maybe MAXIMUM 5" diameter, weight MAXIMUM; 60 LBS? You should keep your chuck pressure around 200 LBS. (without seeing the part). I don't want to sound rude but I am assuming you tighten the bolts on the chuck, closest to center line of the chuck first, then the outside bolts. If that doesn't help at least you know how much you need to taper the bore. But I think .02 is alot maybe you should have someone look at it. I am not familiar with that brand of chuck we use Kitigawa. Robert

[NJC]

Yep, I thought .020 seemed like alot myself, that's what concerned me. I only have a piece of 1.25 steel round bar, about 10" long in the jaws, maybe weighs 5 lbs.

Yes, I did tighten the bolts :idea:

How would I check and/or adjust the chuck pressure?

Scott

[cad01]

chuck pressure adjustment should be on the back of the machine.

[littlerob]

Yep, I thought .020 seemed like alot myself, that's what concerned me. I only have a piece of 1.25 steel round bar, about 10" long in the jaws, maybe weighs 5 lbs.

Yes, I did tighten the bolts :idea:

How would I check and/or adjust the chuck pressure?

Scott

Did you tighten them sequentially center to outside? (I know it seems obvious but if you tighten the outside bolts first it will pull the true position of those jaws out, you want them in a TRUE position).

For the pressure, there should be a pressure guage, and a twist knob for adjustment, just to the left of the door, the knob should be behind the first panel you can access to the left of the main door. Robert

[Thawk53]

Make sure that your jaw bolts aren't to long. If they are to long they will go thru the t-nuts and bottom out in the master jaws before your chuck jaws are tight.

Rick

[littlerob]

Make sure that your jaw bolts aren't to long. If they are to long they will go thru the t-nuts and bottom out in the master jaws before your chuck jaws are tight.

Rick

Good call I didn't even think of that, Robert

Usually the simpelest solution is the right one.

[NJC]

Thanks for the input guys, the jaws are tight and the bolts are not bottomed. BTW if the bolts were bottomed out the jaws would be loose, it would not cause them to be misaligned. Seems to me that I just need to bore them straight. I was thinking of clamping the inner chuck jaws, (serrated parts of the chuck that hold the jaws) onto a round ring or a disc so the jaws have the proper pressure on them when I bore the jaws, sound correct?

[Jarwalcot]

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