JOBO processing wihout water bath

[bill_carnell]

I have used my CPA-2 for years for color where temperature control is

necessary. Someone asked if the water bath would be necessary for B&W

film or print processing. I see no reason for the bath if the pump is

disengaged since room temperature is usually fine.

 

Does any one see any problems with "running dry"? Will appreciate

your comments. Thank you,

[filmbase]

Hi Bill,

 

I�ve been using my CPE-2 since 1990 for black and white film

only and I�ve had no problems "running dry". BUT, shortly after I

started doing that a fellow JOBO friend suggested I put in just

enough water to cover the heating element at the bottom of the

bath to prevent it from possible burn out.

 

I�m not too familiar with the heating device of your CPA so this

may not really apply to you. But if is similar to the CPE, I am

passing along this suggestion

 

**Personal Opinion**

 

Recently I've been filling the bath completely to keep all my

chemicals at my "personal" temperature of 75 degrees. I know

black and white is not as critical as color but consistency doesn't

hurt.

 

Hope that helps.

 

-- Jeff

[chris_eve]

Not sure about your model - my (very) old Jobo had solid nylon? rollers which didn't like running dry, even if lubricated. Jobo recently supplied me with a pair of "Easy Running Rollers" (their description) specifically recommended for this purpose. They also work "wet" :-)

[bill_carnell]

Thank you. Just need to turn the temp down so pilot light on heater stays off I guess. Mine is an old one so will watch the rollers

 

One note you may find of interest. I was concerned about slime developing. No help from JOBO. Problem because anything containing chlorine could cause corrosion. Found stuff for fish ponds which worked well. Finally put a sink drain fitting in with rubber stopper on chain. The 6" long x 1 1/4" drain is on an end extending beyond the top of a 22" high support table. Just dump to bucket when through and refil with warm water for next color print run. The fitting connects flush inside and is sealed from outside with a rubber gasker and threaded collar.

[gary_frost1]

On my CPA-2 the heater will only turn on if the pump is turned on.

So by leaving the pump off you avoid the chance of burning up the

heater when running it without water.

[alberto pastorelli]

Yes, if you switch OFF the pump and the temperature dial (lower) there's no risk at all.

The only problem, as Jobo states on their website, can arise from the rollers, so Jobo strongly advice to use the unit filled with water anyway.

 

regards