Mill Quil play before lock down

Chris, very interesting with the Quill and the spring tension. How do you get the pinion to engage into the rack of the quill to reduce the backlash? Or is that the backlash of the micrometer dial on the fine feed you are talking about?

My quill moves on a funny angle with a sideways movement when looking at it from the front. Fore and Arft seem fine. But the real strange part is that you can get the head true to the table over like 150mm or so, on the spindle, then the quill does not follow an angle plate or a bottle square as it is raised and lowered.

I will try increasing the spring pressure, and see if that makes any difference. The other option is to create a locking collar guide like the video link shows, and fit that to the bottom of my mill casting also.

Its been an interesting read for sure. Maybe I need my casing line bored and sleeved etc to properly fix it and have the back section also recut true to the run of the spindle. All of that will be serious work with some of it needing to be outsourced. There is a company with a line boring set up very close to where I live. But that will be if all else fails.If I resleeve I will use the Bronze bush that has the carbon oil retaining pads, instead of just the cast iron.

Neil

Note: The quil fine adjust worm gear, you as operator willingly ...engage or disengage... by turning a knob deeper at the 3x levers mount (Where some fits a steering wheel) of the normal quil movement. You cannot have both at the same time, either the one or the other.

Jason B
-Interest about the larger knee mills and they not using the quill for fine adjustments. Maybe theirs are doing the same thing by touching the micro feed while the quil is locked, then unlock it and boom the height had changed without you ready for that-?

Paul

-The mill is new. I would not like to do this just yet, untill I clarified this understanding more, and can give the company a better maybe explanation. I am pretty sure if they give me another one of the same, it will just be the similar, and this is the only one with the swivel bed. I will try to discuss it with them and see if they get what I am trying to illustrate.

Neil

- I will play for another week with it before making any changes further, including cutting and measuring the result to see if I got what I thought I cut.
-Also I never before playing with the fine adjust of the quil, when I lock it down, for the dial indicator not to move less than .1mm........Only after I adjusted the spring tention it it got down to .01...Zero, so the spring tention must have done something.......THe "sponginess" I detected, I think must be the grease I added to worm gear.

Note: When you lock down the quil, you can adjust the micro-feed wormgear, that small handle will move either way...The Quil is now locked, however not the wormgear by design......What then happens in interesting=If you moved the micro-feed handle by any means=If you now release the quil lock, the quil WILL move because of that backlash, and interesting with the tighter spring it will move actually faster than before.

Note: By going the route of adjusting the head up and down by adding a ratio to get a finer adjustment, can eliminate all this on the quil, I then just lock the quil and move the head and lock that, I must still test how the head react if I lock that.

Edited By Chris Mate on 12/03/2022 07:52:53

Edited By Chris Mate on 12/03/2022 07:58:09

Edited By Chris Mate on 12/03/2022 07:59:43

Ok, after a day not touching the mill, I decided to do a little experiment with everything/the grease settled down.
1-Spring tention still as I left it after cranking it up.
2-Grease still not removed from worm gear.

The Dial Indicator has 10mm travel and thats what I am checking out from zero travel of the quil.
-Travel and deviation on quil lock as spring gets more tighter as quil goes down.....

Travel=.01mm...........Deviation=.03(Way better than orininally)
Travel=.02mm...........Deviation=.03
Travel=.03mm...........Deviation=.02
Travel=.04mm...........Deviation=.01
Travel=.05mm...........Deviation=.01
Travel=.06mm...........Deviation=Zero(Spring reach required tightness it seems)

Travel=.07...to....10mm=Zero(I saw a few .005mm variations in between, less than a 1/4 of tests)

Travel...So it seems after the initial travel down of .06mm its prety much zero deviation if I lock the quil.
Now this never happenned in 10mm travel with the spring more relaxed.

-Next step is to remove the grease and see if theres any difference with it removed.
-To increase the spring tention another notch after making a tool to grab the spring holder without messing up some fingers if it slips.

I put some conical disk springs under the quill locking lever. This allows a constant force to restrict play to give consistent movement of the fine feed.

Martin C

Martin Connely: I found what you did very interesting.......After all my thinking and experimenting previously, and I understand the conical spring washers are stiff(Relative), Is there s change, and I am not sure if you lock down it fully(100%) or keep it semin locked down say 70% meaning the fine feed can still adjust with constant move as you decribe.

My question is, if you keep it at say 70% locked with washers, will some cutters be able to pull the quil down while you taking a somewhat heavy cut to remove material-? This is a problem I saw coming playing with lighter restrictions-?

I have my spring set up so that the quill always rests downwards on the mechanism so it is already down. I got the thinnest springs and stacked them to get the force I wanted. I can still put on full lock when needed.

Martin C

Edited By Martin Connelly on 15/03/2022 07:59:27

A-So this week I made a holder vthat fits slipfit over the quil spring cup.
-I bored it out to fit, then drill and tap 8x 8mm holes evenly spaced, made a gap on the inside to accommodate the end of the spring that protrudes the cup. I bought a knob with 8mm tread on it some time ago from 2nd hand shop, and it fit like a glove for this purpose to adjust the spring not to damage yiour fingers/hand as it gets stiffer.
1-You remove the quil lock handle(Easy, quick).
2-If spring in unwinded, you wind it up till it may slip out of hand and you has to do it all over.
3-Now you fit this tool over and screw the 8mm gear lever handle in one of the treads to have leverage tightning direction. Then you tighten the other 7 bolts. Now the spring cup is gripped and you can upwind it a notch or two.
4-This worked great.

B-I discovered another problem.

THis mill has the spring cup hold in place that it not fall out and unwind by a known + washer that screw in. The problem is when you tighten it, the washer pushes against the cup and that causes the quil to have a spongy feeling(Not the grease) just before it reaches the home position, lets say the 3-5mm. For me this is a problem.

To solve this I inserted a smaller washer below the large washer to prevent the larger washer to push against the cup firmly. Now the quil return firmly back that last 5 mm. If you dont tighten this knob. My drillpress has similar spring cup design, but does not have this problem.

I did read up on other mills, and the various opinions on quil spring tention, neutral even in bridgeport case with tool weight taken into account.

Now with this all fixed, I will try to mill using the dial indicator, then measure it to see if I mill as accurate as I think I am by using the quil lock & fine adjustment in certain order. As soon as the quil is locked, the fine adjustment must not be touched at all. If milling cycle is complete, the quil lock is unlocked, the dial indicator stain same spot, the fine adjustment handwheel is adjusted in correct direction, the dial indicatr indicate next cut depth, you lock the quil, dial indicator do not move, you mill & repeat.....This is now my understanding of how I can use this mill in this way Z2 Axis. (Z1=The head up or down)

Note-1: I will think about the fine adjustment handle holding its position, or at least if you touch it, not mess up your depth by unlocking the quil. I found that putting resistance in quil lock assembly can give you false feeling of backlash, and if quil is unlocked, you will see it drops unexpectedly, which can interfere with your cuting expectations...This is just my opinion now or the time being.

Note-2:I had relook at Drill Press with similar quilspring assembly. The drillpress has 2x locknuts so you can tighten them without screwing the springcup down on shaft and the drillpress has a small play here, unlike the mill had.

Edited By Chris Mate on 19/03/2022 21:22:33

Edited By Chris Mate on 19/03/2022 21:23:34