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Dr_Rocks
3-May-2012, 14:05
Hi all,

I got a HP combiplan 4x5 tank to develop my first negatives in, and I'm pretty happy with it so far, but I've noticed a few times that the negatives slide out of the slots and stick together, causing uneven development. They load in just fine, but I'm guessing the agitation is what moves them around. Looking at the rack, it seems the side with the screws is perfectly tight, but the other side of the holder moves around a bit, causing the negatives to slide out. Any suggestions? I was thinking of shimming it with something, or just gluing it together, but I'm not sure.

Thanks,

-Chris

Jon Shiu
3-May-2012, 14:27
One tip is to only agitate in the direction of the edges of the film, ie rotate around the narrow side of the tank. (I'm not explaining it clearly, but you can figure it out.) That will keep any sideways forces on the film to a minimum and hopefully keep them from coming loose.

Jon

Gem Singer
3-May-2012, 14:55
Are you installing the orange film retaining clip on the top of the film rack, after loading the films into their grooves?

If installed properly, it prevents the film sheets from popping out.

Also, there is no need to agitate aggressively. Continuous rocking for the first 30 sec. Then, slow deliberate rocking for15 sec., at 1 minute intervals.

See the article I wrote:"Developing B&W 4x5 Sheet Film-An Alternative Method".

On the LF Home Page. (click on the dark blue tool bar above).

Frank Pittel
3-May-2012, 21:18
You also need to be carefull not to push the retaining clip down to far. Just enough to keep the film from shifting in the hanger.

Ian Gordon Bilson
6-May-2012, 03:18
Not having ever had the luxury of a retaining clip,I have been very happy with the lift and tilt method.
You do need a darkroom for this method though.

Dr_Rocks
6-May-2012, 09:29
Thanks all. I'm guessing I either agitate it too much, or push the clip down too hard (probably both of these things!).

Bruce Douglas
9-May-2012, 12:28
My CombiPlan came with plastic washers which go underneath the nuts which screw onto the orange rods. The clear plastic ends are held together by the rods. The plastic washers allow you to tighten the nuts enough that the clear plastic pieces won't wobble. If you do not have these, I don't know if the washers are available as replacement parts.

Bob Salomon
9-May-2012, 14:36
The blue plastic washers are not for 4x5 with a Combi-Plan and should be thrown away as they space the ends too far apart. Their only use was to space the ends properly when using the 2x3 divider plate to process 12 sheets of 23 film. That plate was discontinued in the 80s but the factory kept including the blue washers.

The way to assemble the carrier so the sides can't wobble is to put it together so the orange lock nuts are on opposite sides of the carrier. One on the left side and the other on the right side. Just make sure that the curved grooves on the ends face each other when you put it together.

Bob Salomon
9-May-2012, 14:39
Make sure that the curved sides of the end plates face each other. Otherwise film can slip out. The straight sides are for glass plates only. Then slide the film clip down so it contacts the film. Sheets can now not slip out.
If you installed the blue washers take them off and throw them out. There is no use for them.
Also check that the spring bar on either side of the clip has not been broken. That happens if you don't gently press the springs in when removing the clip from the rack.

Dr_Rocks
9-May-2012, 21:20
Make sure that the curved sides of the end plates face each other. Otherwise film can slip out. The straight sides are for glass plates only. Then slide the film clip down so it contacts the film. Sheets can now not slip out.
If you installed the blue washers take them off and throw them out. There is no use for them.
Also check that the spring bar on either side of the clip has not been broken. That happens if you don't gently press the springs in when removing the clip from the rack.

Thank you! I had the plastic washers installed, this must have been causing these issues. I seem to have been doing everything else correctly.

Thanks for the help!

-Chris