Quill Freeplay

[DLB]

David, I had to go look at my old "Quill Questions" post [not sure how to link back to that] where I said, ".012" play when unlocked" ...not 13. Sorry for the wild exaggeration . But it did greatly improve by tightening the quill lock, then backing off just a little. The challenges are 1) getting it just barely loose enough for the spring to retract the quill, and 2) how tight/loose that is varies through the quill travel. As to method of measuring, I clamped a dial indicator onto the main table. Table deflection should be even theoretically next to nothing as long as I keep my hands off. I would have to rearrange the dial position to match whatever quill advance I make... Probably makes more sense in the photo I took of how I measured the runout on my original quill, except in this case I pushed the quill up, then down to induce the deflection:

Creekwood freeplay.jpg (136.31 KiB) Viewed 1526 times

Note: portion above is quoted from another thread.

Using a similar setup, except that I used a magnetic mount on the way tubes rather than attaching my dial indicator to the table, I measured 0.003" vertical deflection under a moderate force. Quill lock fully loosened, depth stop loose (don't think this matters), quill fully retracted, dial indicator in contact with the flat near the end of the spindle. That's much better than I expected, sample size of one. I was applying enough force that this might be overstated. I should test again, finding a way to mount the indicator to the headstock to eliminate the possibility of movement not actually related to quill freeplay.

Suggestion: Try repositioning your indicator so that it is in contact with the quill 'barrel' rather than the spindle. You can measure where the lower saw guard attaches. This should help to isolate whether the quill assembly is moving within the headstock as opposed to the spindle moving within the quill assembly. If you have alternative indicator tips, a flat one will give more reliable results measuring a rounded surface. (Your other symptoms, especially that partially tightening the quill lock reduces the free play, seem (to me) consistent with the barrel moving within the headstock.)

- David

[JPG]

When Y'all say 0.0xx deflection is that 1)vertical up, 2)vertical down, or 3) both(1+2)

I think the unmolested table is an ok reference.

Whether the deviation is due to quill body or bearing slop does not matter unless you are trying to determine actual cause.

The end result at the bit tip is what we need to be minimal.(but that also includes arbor/chuck slop...)

[DLB]

When Y'all say 0.0xx deflection is that 1)vertical up, 2)vertical down, or 3) both(1+2)

When I say it I mean both combined, or Total Indicated. For example deflection readings of -0.001" from reference to +0.002" = 0.003" combined. Headstock is horizontal. Indicator is pre-loaded to ensure it is measuring both deflections.

- David

[CreekWood]

Same here in terminology--total deflection is the sum of pushing downward on the spindle, then lifting up...and not being too aggressive. The .012 was at full quill extension and with no tightening of the quill lock. When the shop warms up, I'll go play some more.

[BigSky]

I push downward (and hold), zero dial indicator, then push up and hold then read result

[DLB]

Same here in terminology--total deflection is the sum of pushing downward on the spindle, then lifting up...and not being too aggressive. The .012 was at full quill extension and with no tightening of the quill lock. When the shop warms up, I'll go play some more.

My freeplay increases dramatically at full extension, close to 0.025". From essentially none fully retracted. Both measured at the spindle, on the flat, with quill lock fully loosened. 50% extension gives about half the free play.

- David

[CreekWood]

The only operations I can think of where the user extends the quill significantly are drilling and morticing. I'm wondering about a couple of things: I'm not sure how to precisely measure whether my quill travels in a smooth path-- i.e. how much does it wobble as it extends. Secondly, and I wonder how much those operations direct their own path, I.e. once a drill bit engages, will it wander?

[JPG]

A twist drill will always tend to wander independently of quill slop. Brad points are slightly better. Forstner bits are best. Spade bits belong in a carpenter/electrician/plumber's tool box.

[DLB]

The only operations I can think of where the user extends the quill significantly are drilling and morticing. I'm wondering about a couple of things: I'm not sure how to precisely measure whether my quill travels in a smooth path-- i.e. how much does it wobble as it extends. Secondly, and I wonder how much those operations direct their own path, I.e. once a drill bit engages, will it wander?

I had some challenges using the machine for horizontal plunge routing recently. Those challenges may or may not have been related to this, but I wasn't getting the precision I was after or expected near the plunge (where the quill was unlocked). I would add routing to those operations.

Scott Markwood (My Growth Rings) did a video on tailstock boring that seemed to confirm (to me) that once a hole is started, whether that is straight or angled, the drill bit will tend to follow the original path. And that has been my experience as well when drilling. Material inconsistency may deflect the path, that is another matter. This might have been one of his follow-up videos that are only public for a week, I didn't immediately find it. But it has never been my experience that Youtube is very searchable.

- David

[JPG]

It is that tendency to follow an earlier drilled hole that makes drilling a small pilot hole desirable.( with typical twist bits(flat point)).

Now back to quill slop.