Taper on grinding wheel

Good morning all, I have been getting .0007 taper when dressing i.d. wheels. Taper is small away from the spindle. I have sufficient coolant and just replaced it brand new. I have checked for alignment and made sure diamond is at centerline. I can not get rid of the taper. I am checking the o.d. of the wheel with some old micrometers and when I grin a part you can measure the taper near the shoulder. The wheel is 1 inch long. Any suggestions?

First thing might be the facet of the diamond.. a sharp point of the diamond might dress with less stress on the wheel
possible more wheel chatter out-board..
angle of dress feed..
angle/tram of wheel head.
direction of dress feed.
might check tram of wheel head with a test bar at top ans side.
bearings in spindle.
pre-load to spindle bearings.
out of balance of wheel.
wheel spindle holding secure.
QT op:The wheel is 1 inch long. what diameter and mounting design?
pull clean and turn holding collet if collet held.
shorter hold on dressing diamond.
larger diameter of diamond shank.
diamond holder bore washed out.

I changed the diamond and have trammed the wheel head. Unfortunately, on the particular CNC grinder, I can only dress starting by the spindle outward. Even dressing manually the opposite way, the taper still appears. I'm scratching my head on this one. The ball screw for the Z axis was just replaced. Can this have anything to do with causing this?

What is your diamond point geometry.
try a different wheel.
tear down whole set-up (wheel off and everything) and set up again to perhaps find a fault.
test wheel spindle.
What design is your wheel arbor?
dressing by hand feed, and other direction should have ruled out the z ball screw.
has this machine worked well in recent past?
QT: [have trammed the wheel head.] front and top?
is this first work after pulling table for ball screw repair??

Perhaps the wheel is spinning so fast a little off/out balance makes it whip a little. .0007 is only .00035 on one side as it would be dressed.
Perhaps cutting wheel to half speed (or what) for dressing.

Does indicating the parked wheel from the dressing direction traveling X show the same .00035 taper? or show straight?

Dose traveling x show any variance going left/ then right on a straight test bar?

Is the wheel a super hard wheel.

One test I used was to dress a wheel then feel parked to a solid side of a parked part and set zero.. then back away and come back in running to see where it hit..this to see how much wheel whip I might have in a set-up.,, some wheel arbors and some wheels would whip more than others. Some wheels went to the dumpster with still looking like good wheels.

First, what kind of grinder is this ?

And second, is the diamond stationary while the table passes by, like an I.D. grinder, or is this some other setup ? Over-the-wheel dressers on cylindrical grinders could have this problem but it's hard if the diamond has a fixed position relative to the ways.

How do you determine that the wheel has a .0007" taper, btw ? That's a little hard to measure.

And this is just after it is dressed, not after a few passes ? Wheels always develop taper when grinding. That's why on an i.d. job I dress at two tenths from finish size ...

You probaly know that but have to cover all possible causes, sorry

Did the damage to the Z ball screw involve a wreck? or a hard bump to your limit stops?
Can you hand dress wheel perhaps with a diamond hone to finish this one job?
Might you program a 2* OD taper dress to the wheel? Agree that does not solve the reason for the problem.
Perhaps looking for something out of square to .001" in 3 inches..(about .00035 perinch to one side of wheel)
I have seen a wheel running at perhaps 10,000+ rpm act like a gyroscope and try to draw a assembly to one direction..
Can you blue up the wheel perhaps with sharpi lines and then come in to skim dress .0001 at perhaps wheel speed of 5,000rpm so to see if RPM is a factor..
what diameter is the wheel.

QT: Emenual: You probaly know that but have to cover all possible causes, sorry
Don't be sorry we should try to cover all the bases.
As you suggested it may be good to try a fixed diamond dress ..if the dress is not fixed but traveling in some device..

Got the spindle rebuilt (bad bearings) and realigned wheelhead (off by .005 over 22" travel). Seems to have solved my problem. I believe it was the wheelhead that was more the culprit ad when I got the spindle back the issue was still there. Thank you for all your input.