C6501 doctor blade gap width

[mrwho]

Good afternoon!

Does anyone have any info on the width of the doctor blade gaps for these machines?

I've got some developing trouble that I traced down to the doctor blade gap, but I'd like to try to adjust it before replacing the entire developing unit (the developer is quite new and I'd like to avoid dumping the developer and putting it on a new unit if possible).

Thanks!

[dljorg]

Re: C6501 doctor blade gap width

Hello -

Had some trouble with doctor gaps on C6500 dev units at my company. We took apart multiple new units to see how they were set from the factory. Gap is generally about 0.8mm with a feeler gauge, However......

1. Apparently the factory uses a special curved tool for setting the gap. Of course you don't have that.

2. If you use a classic flat bladed feeler gauge the angle at which you hold the gauge will make a huge difference in the actual gap.

3. The application roller is not perfectly round - most units will have a black felt marker line at the high spot.

What I suggest is that you get a new unit out of the box and use the feeler gauge you have to get an idea of how to hold the gauge in relation to the roller. What I tried to do is hold the gauge at a (math term) tangent to the roller right under the doctor blade. There are screws on top of the metal doctor blade that you loosen, move the plate and tighten to adjust. Tightening the screws will change the adjustment so you will have to check with the gauge multiple times. Also I found the best way is to adjust one end of the blade, then the other end and then go back to check the first end again. It may take 3 or 4 adjustments to get both ends the same. Be patient. When its right and you have the gauge angle correct a 0.8mm gauge will fit in but a 0.9mm gauge will not.

dljorg
Waterbury, CT

[RRodgers]

Re: C6501 doctor blade gap width

All 4 units are rhe same, just measure another color. Of course make sure the mag roller is clean before measuring and use the same angle on both.