Meanwhile,
I did some experimentation and found when I invert the roller no change in curling issues, but when I swap sides the problem stops.
There isn't much one can do for adjusting reel torques on this particular deck (teac x10r)
I bounced a few ideas off Sam as far as making a few circuit mods but with him being quite busy, I'm sure he hasn't had time to give the ideas any thought.
My measurements put reel torque levels with-in factory specified ranges, abeit on the low side, again I'd like to alter the circuitry to make torque levels adjustable.
BTW:
The curling only happens on certain tapes. Not sure why this is, and if I provide increased drag on the supply reel, the problem also stops.
The rollers are in good condition with no issues, the rubber is solid but pliable, no defects.
The bearings on the other hand appear to be fairly worn. I took some measurements and the roller shaft is .190 in diameter, the bronze bushing, however has a diameter of.205 inch.
The net result is radial play of .015 and is clearly too loose and probably accounts for poor wow/flutter and potentially the tape tracking issues.
I did a bit of research on retro fitting precision bearing into the rollers and it appears that a 5x13x4 mm could be utilized, however the bronze sleeve would have to be removed, easy to do and the aluminum collar would have to be reamed to allow for the bearings larger size, do-able but easy to screw up. Going with a bearing solution reduces the play to apx .006 so a big improvement in play but no guarantees it will fix the problem.
Play could be further reduced to .0005 by the use of loctite, basically gluing the bearing to the shaft
I've sent an email to Terry's rubber rollers describing my project for his review, but no reply as of yet.
I also found a posting on a forum at homerecording.com where others were having the same problems and one poster suggested that having a mirror smooth capstan could be a possible cause. The X10 has this style of capstan
I had to post a response to the effect that maybe one could use 600 + grit sandpaper to remove the mirror finish. again no response.
well, never a dull moment around here...