RPM for Jobo 3010 with Beseler motor base? [Archive]

View Full Version : RPM for Jobo 3010 with Beseler motor base?

brian steinberger

25-Nov-2006, 09:49

Jerzy Pawlowski

25-Nov-2006, 17:25

I have encountered same problem recently when I got Beseler base and Jobo 3010. It runs at about 32 rpm which appears too fast for me. I tried to slow down with simple light dimer, does not work, cuts too much power. Then I tried with variac and it is much better. I can get between 16 to 20 rpm, it corresponds to 76 to 78 V, at 75V it stops. However I am not extremely happy with this setup, rate of rotation strongly depends on amount of liquid in 3010 and it is hard to control. I am still playing to get better feeling. Few days ago I have asked Sandy King on one of treads regarding speed/Pyrocat matter and his reply - anything below 20 rpm is OK.

Eric_Scott

25-Nov-2006, 18:03

As they say, YMMV. I just started using my 3010 drum with a Beseler motor base I recieved recently. Maybe it's just luck, but my development time is exactly the same as my time for tray processing 6 sheets of film. Needless to say, I'm very pleased with this setup. Just try it and see what your results are. You may need to make several runs to dial in your time. Once that's done you're set. I don't know if this matters, but I do use a 5 minute presoak.

Eric.

Jerzy Pawlowski

25-Nov-2006, 21:02

Eric, do you use base at full speed. I have no problem with time, but when I am slowing down I have impression that the rotation speed is not exactly the same during whole process. In summary the system works great, I am only worrying about reapetabality. May be I should simply use on full speed - 32 rpm. I use presoak, however only 3 minutes. Did not notice anything wrong, I think I will extend to 5 minutes, can be better only.

Eric_Scott

25-Nov-2006, 22:30

Jerry -

There must be different Beseler motor base's available. Mine operates at only one speed. It has a switch to reverse directions. I don't use that feature. I timed the rotation, but can't remember what it was. I don't know if my unit slows down during use. I'll have to look for that. Don't get me wrong, I'm no expert. There are a lot of others folks in this forum who know *much* more on this topic than I do.

Eric.

Jerzy Pawlowski

25-Nov-2006, 22:36

I am sure it is the same base with one fixed speed, but I am slowing it down using variable transformer (called variac). When voltage is lower, then motor is weaker and does not act perfectly. Still it is just observation. When at full, normal speed then everything is fine.

Ron Marshall

26-Nov-2006, 06:56

I just got my beseler motor base today. I didn't receive my Jobo 3010 yet. The beseler came with some sort of tank that I put on it and ran it. It seems to run really fast. I have no idea though. I'm sure the Jobo 3010 is larger than this drum.

What revolution rate is adequate for the Jobo 3010?

The Jobo technician I spoke with recommended 50 rpm for the Jobo 3010 for hand-rolling on the Jobo roller-base.

That speed has worked well for me.

brian steinberger

26-Nov-2006, 12:14

The base that I have is "Color by Besler". Mine has one speed and NO reverse switch. I plan to pick the tank up and flip it every minute or two.

Dave Aharonian

26-Nov-2006, 12:21

I have a "Color by Beseler" base with a reverse switch (which I don't use). It spins at about 30prm. I pick up the tank and reverse it every 30s. I don't use Rollo Pyro - I just use regular PMK with a tiny amount of EDTA added and I get perfect development every time. Good luck!

Jerzy Pawlowski

26-Nov-2006, 12:33

The Jobo technician I spoke with recommended 50 rpm for the Jobo 3010 for hand-rolling on the Jobo roller-base.
I am not surprised since it is their minimum. To make it slower the motor would have to be better. For most developers it is OK but some may oxidize too fast. It is my only concern.

The base that I have is "Color by Besler". Mine has one speed and NO reverse switch. I plan to pick the tank up and flip it every minute or two.
I don't think it is necessary, Jobo 3010 is designed the way that movement of liquid is good in both directions (along and across rotation axis). This may be even worse if you will not synchronize flipping with full rotations of the drum. I have two bases, same as yours and one with reverse switch but I am never using the latter feature.

Michael Daily

29-Nov-2006, 17:35

The base that I have is "Color by Besler". Mine has one speed and NO reverse switch. I plan to pick the tank up and flip it every minute or two.

I have the same base and replaced the switch with a dimmer suggested by an electrical supply store. It works OK and can be dialed down to about 28 rpm. film development is even and repeatable with the basic Bessler tube for 8x10..
Michael