CX601 Milling Machine

[EddyCurr]

The machine I looked at appeared to have a hole
in the side of the larger dia segment at the end of
the spindle that has the female taper for the R8 collet
where yours is cracked. Visible when the spindle is
fully up.

Your photo corrects my erroneous impression that I was
looking at the hole for the pin - your pin is higher, up
above the bearing inside the quill where it is unlikely
to be seen at a casual glance.

Still, there was a hole in the lower section. When I
posted earlier, I was musing about the possibility of a
pin in this lower location being inset so far as to create
a sidethrust on a collet as the collet was pulled up into
its seat.

.

[boslab]

Irrespective it looks vaguely het treatment fault or failure from memory, should not have cracked I'm thinking, is it returnable, I'm sure the supplier would exchange somthing like that myself, I had a socket crack in a snap on socket set i bought years ago, they gave me a new set, not just the cracked one, they were more insistent on getting the fracked one back, suppose the met lab were bored or somthing, they also wanted the photo I sent them to be theirs not mine, made no difference in the end as the bloody thing got stolen, don't think I'm ever going to buy an 3/4" drive socket set again!,
Mark

[BMW Rider]

The mill had a three year warranty which ran out eight months ago. I doubt they'd entertain a claim now.

[EddyCurr]

You will not know if you do not try.

Are you the original owner and is the machine's purchase history in
the vendor's database? Do you own other machines marketed by
Busy Bee? Other tools and accessories? Have you got rapport with
members of the sales staff?

Have you posted/searched elsewhere on the net for indications that
other CX601 owners may have experienced a similar issue? One man's
approach suggests that prudence regarding the tone of any statements
uttered going forward may retain & build goodwill towards a satisfactory
outcome.

What would be a satisfactory outcome in your estimation? I wouldn't post
the reply in an open forum at this point, but thinking the question through
seems a worthwhile exercise.

.

[RB211]

Just curious, how hard were you torquing down the collet? Unlikely the threads would be strong enough to cause this, but if the part wasn't heat treated properly, perhaps over time it was enough to do this.

[BMW Rider]

I did question myself as to if I was too heavy handed tightening the collets in. I tried to search for information on how tight they should be, and the common theme that I came to find was good and tight and that the drawbar threads would be the typical point of first failure. My drawbar is just fine, so I would say over tightening would not seem to be the issue.

I also searched for other reports of problems with this machine and found very little on this machine at all and nothing related to this.

[BMW Rider]

As promised, the new spindle arrived yesterday. Got the machine reassembled and running again. Nothing remarkable to note with the new part, it is visually identical to the old one (aside from the crack).

[EddyCurr]

Did BusyBee express interest in examining the original spindle or offer any relief under some sort of Customer Satisfaction program?

.

[BCRider]

I did question myself as to if I was too heavy handed tightening the collets in. I tried to search for information on how tight they should be, and the common theme that I came to find was good and tight and that the drawbar threads would be the typical point of first failure. My drawbar is just fine, so I would say over tightening would not seem to be the issue.

I also searched for other reports of problems with this machine and found very little on this machine at all and nothing related to this.

I wondered about this as well. Of course if I used a Weldon shank holder with the set screw it only needed moderate tightening to stay true. But I'm all OCD about needless tool overhang. So I was hoping I could use the R-8 collets directly for the end mills to both limit the overhang as well as try to reduce the runout.

What I did was run some tests using a 3/8 collet with a 7/16 two flute end mill, a 1/2 inch collet with a 1/2 inch two flute end mill and a 5/8 collet with a 3/4 inch 2 flute end mill. The shanks and collet jaws were cleaned of any packing grease and lightly oiled then wiped off to remove any excess. Once set in the collet a witness mark was made across the joint between shank and collet with a fine tip felt marker. To tighten the collets I held the nose of the spindle with one hand tightly and gave the end of the 10 inch wrench a few good thumps with the palm of my other hand. I'd have to check to measure the foot pound this created. But it isn't much. For the larger sizes I gave the wrench a couple of extra thumps and hold the spindle with a bit of leather to provide more friction. But even with that the draw bar loosens up quite easily and the collet taps out with no more than a bump or two from the hunk of lead I use for this sort of thing.

At this point it was a year ago and I honestly don't recall how deep of a full width slot I managed to cut without any movement in each size. But it was enough that I trust the smaller size mills and collets to do anything that I feel OK to push the cutters to doing. On the larger sizes I did get some slippage when I was getting down to what I'd consider as "hogging" cuts. Like 1/4 deep full width slot in mild steel with the 5/8 end mill. But even then just holding the spindle nose with something to give more friction and an extra twist on the drawbar fixed that. And even with that much the torque was not what I'd call very high. Certainly nothing even close to straining the draw bar threads.

How does this compare to what you were doing? I know you posted that the drawbar isn't showing signs of abuse at all. I'm more curious about if my own method is typical or not and if I should be worrying as well. After all it wouldn't take a whole lot to make up a ring from some tough alloy and press it into place on the nose of the spindle. And given your experience I'm considering doing just that.

I also wonder about heavy interrupted cuts such as with a flybar. The crack doesn't need to come from ONE source. Tightening the drawbar does put some stress on the spindle taper. But so would heavier interrupted cuts. Any thoughts based on how you used the machine?

[Rustybolt]

The mill had a three year warranty which ran out eight months ago. I doubt they'd entertain a claim now.

Never hurts to ask.

[brian Rupnow]

Today I have to add a new chapter to this story. This mill has a high speed/lo speed selector knob, which gives the same effect as putting a lathe into "back gear". About a month ago, during heavy drilling with a 1" diameter drill, in "lo speed" the selector knob jumped out of gear. I said "Oh Dear" or something to that effect and clicked the selector back into "lo-speed". That fixed things for a little while, but the mill kept doing that repeatedly on any heavy drilling jobs I had from that point on. Yesterday, during a heavy drilling job, the lathe went "crunch" and I totally lost the "lo speed" function. I'm sure I have stripped the teeth off a gear in the head of the machine. I called Busy-Bee head office in Toronto this morning, and they do stock spare parts for this mill, which was purchased in 2015. Sometime this week I will pull the top off the mill, and try to find what I need to replace. If I find that it is too complex to fix in my shop, the entire head of the mill can be stripped from the column by removing two bolts, and I can take it down to Busy Bee for repair. The high speed function still works correctly, but I need that "lo-speed" function more than you would think. I really like this mill, and it has given me excellent service since I bought it.---Brian

[Black Forest]

Today I have to add a new chapter to this story. This mill has a high speed/lo speed selector knob, which gives the same effect as putting a lathe into "back gear". About a month ago, during heavy drilling with a 1" diameter drill, in "lo speed" the selector knob jumped out of gear. I said "Oh Dear" or something to that effect and clicked the selector back into "lo-speed". That fixed things for a little while, but the mill kept doing that repeatedly on any heavy drilling jobs I had from that point on. Yesterday, during a heavy drilling job, the lathe went "crunch" and I totally lost the "lo speed" function. I'm sure I have stripped the teeth off a gear in the head of the machine. I called Busy-Bee head office in Toronto this morning, and they do stock spare parts for this mill, which was purchased in 2015. Sometime this week I will pull the top off the mill, and try to find what I need to replace. If I find that it is too complex to fix in my shop, the entire head of the mill can be stripped from the column by removing two bolts, and I can take it down to Busy Bee for repair. The high speed function still works correctly, but I need that "lo-speed" function more than you would think. I really like this mill, and it has given me excellent service since I bought it.---Brian

In the works of our late illustrious Sir John, "Clumsy Bastard" A 1" drill might be pushing your mill I think...just sayin!

[Cuttings]

Good morning Brian. You should be able to handle the job just fine. I have had just about every part of the head on mine apart at some time. If you look at page 13 of the manual it gives an exploded view of the head. If you want to have a look at what is going on in there roll the head all the way with the top to the right and you can take off the #299 inspection plate on the back. Through there you should be able to see what is going on. I usually remove that plate 2 or 3 times a year to make sure are still well greased. The original grease in my opinion wasn't all that good. I found some from Petro-Can that has a high adhesive value and it seems to stay on a lot better. If you run a lot at higher speeds it is still going to throw most of the grease off. In mine I also found that the #292 lever was not mounted in the proper position on the #290 shaft to get full engagement of the gears in one of the speeds. I believe I made a new #290 shaft because the lever kept jumping back to it's original position on the shaft. If you have to replace the shift gear you need to remove the motor off the top and maybe even the #234 adapter plate to get the shaft out. hopefully the gear on the quill shaft is still OK. I have had that out too, but it is quite a bit more work. Hopefully this helps a little. If I can be of any more help just shout. I pretty well know this machine inside out and backwards by now.

[brian Rupnow]

Yes, a 1" hole in steel is pushing the limits of the machine a bit. Cuttings--I am just finishing up some contract machining for one of my old customers. I finished the last part about 10 minutes ago. I talked to the technician at BusyBee in Toronto yesterday (to see if they kept replacement gears in stock) and he said it shouldn't be a real tough job to get to the broken gears. I will find out a bit later this week. Will probably do a thread with pictures when I do it.

[brian Rupnow]

Cuttings--Are we talking about the same cx601 mill? This is a picture of my mill with the top cover removed. Don't let the sprocket and chain fool you--that is a modification I made so I wouldn't have to reach up so high to raise/lower the head. (I have a torn rotator cuff in my right shoulder that can't be repaired). Unfortunately I don't have access to the back of the mill, so I will have to remove the motor and the motor-mount plate and go in through the top.---Brian