View Full Version : Jobo Light Trap Q's

Steve H
20-Jan-2006, 06:41
As you will recall, I have had poor luck with the Unicolor Drums, and therefore am looking into using a jobo drum on my unicolor base. However, I find the prices of the Jobo items completely outragious. $259 for a plastic drum ? P.T. Barnum's skeleton must still be grinning ear to ear.

So, Im going to attempt to make my own version of the drum. My question is how does the light trap (if there is one) work on an expert drum ? Is it in the cog assembly ? If so, how does the trap work on a 2551 setup with the magnetic lid ?

At this point, I have two options. #1 would be to make 'torpedo' tubes that would fit inside of my 11x14 unicolor drum, and function similarly to the expert system. Or, I can make a new PVC housing with the tubes inside of it - this however would require the manufacture of a new light trap.

I have not been able to find some detailed photos of the expert drum's internals, but I suppose each film tube is ribbed to keep the film off of the walls of the tube ? If so, the way that I would plan on ribbing the inside of my film tubes would be to glue 5-6 beverage stirrers inside of the film tube, which should allow proper circulation. I suppose I could even slot the tubes in between these ribs to assure flow.

Thanks !

20-Jan-2006, 06:48
You can buy a new 2551 for a lot less then that. A used one for even less.

The 25xx type film tanks have a funnel inside the lid. The funnel connects to a tube. The combination makes the light trap. Both the cog and the magnetic lid are the same.

Ron Marshall
20-Jan-2006, 06:59
Steve, Jobo expert drums can go for around $100 on ebay.

I have the 3010, which I highly recommend for ease of use etc.

The drums are like cylinder of a revolver. The walls of the film "chambers" are smooth, except for two ridges, which hold the sheets in place.

The light trap is like a round flat plate inside a funnel. The opening is narrow, and the plate and funnel are parallel where they are in close proximity.

Steve H
20-Jan-2006, 07:13

Thanks for the quick replies. I've been keeping my eye out for the 25xx on ebay, ditto for the expert 3010. The 2551 setup doesn't look too bad, but I wonder how easy the reels are to load in a darkbag. Even used it seems as if the 3010 goes for $140s. Being as I have the unicolor drum already, I figured perhaps I'll give it a shot.

What Im thinking of would be to try some 1.5" ID PVC as the tubes, glued around a 1.25" ID tube in the center. This would make the setup fit snugly into my Unicolor drum, and it should allow me to do 12 sheets at a time.

We'll see what happens - thanks for your help !

Ed Richards
20-Jan-2006, 07:52
There is some pretty impressive plastic forming in the Expert drums, and they keep the weight down, which becomes an issue.

The ID should be more like 2.25 in, or you may never get the curl out. What will you use to fill the space around the tubes so that all of the developer stays in the tubes?

Mark Carney
20-Jan-2006, 08:30
You can get a loader guide for the 25xx reels.
I never got the hang of using it though and ended up loading the reels by hand.
Still not a very practical way of doing things but alot less expensive than the expert drums.

But the results are very good and consistent! Even with a unicolor motor base.

I have since gotten a 3013 tank for 4x5. It was less expensive than the 3006 or 3010, which I am still looking for.


20-Jan-2006, 09:27
Steve, I tried to email you but AOL bounced it cause it's hotmail. I've got some things I was going to sell on ebay. Email at lrpete@hotmail.com if you're interested. Len

Steve H
20-Jan-2006, 10:46
Thanks again for the replies. I honestly would want the 2551 setup, but yet again on ebay they are going over $100, and I cannot justify that, as I can get 5' of PVC for less than a 10th of that. Im going to try a couple of ideas, and I'll report back later this eve.

Thanks !

20-Jan-2006, 11:48
Buy just the tank on Ebay. With some patience you'll find a tank for far less then that. Once I bought a 2551 and a 2581 plus 12 2502 film reels and a collection of pitchers,film clips etc. All this for $50. I've bought two 16x20 print tanks and a 11x14 for about $30 total. Just keep your eyes open.

Once you have the tank a new 2509N reel from B&H is something like $30. Personally I see too many questionable reels on Ebay going for too much money. Some are missing the inserts. Some are the older style. Not worth the effort for reels.

If you're going to use this on the motorbase don't ignore the 2581 8 reel tank. The things are often cheaper because people don't want anything that big but except for the higher use of chemicals it'll be just fine on the motorbase.

Steve H
20-Jan-2006, 13:27
Ok, so Im scrapping my idea. First off, it seems no matter what I do, the PVC is scratching the negs. Secondly, my Unicolor drum leaks anyway. So basically what I need here is a 2551 tank and 2509N reels ? I believe the 2551 would take 2 reels - correct ?

Thanks again.

20-Jan-2006, 16:01
A max of two reels. But you can start with one. The bigger 2581 takes a max of three. Buy which ever one is cheaper. If you're doing B&W the added chemicals aren't a big issue. The 2551 needs at least about 600ml the 2581 at least 1litre.

Steve H
20-Jan-2006, 16:10
Interesting. I don't understand why people complain that Jobo's use lots of chems....In my 8x10 trays, Im using ~460ml of solution to develop 4 negs at a time. Hopefully I'll be able to come up with a drum shortly.


21-Jan-2006, 04:37
In rotary mode [like on the motorbase] the don't use much at all. The motorbase is actually an improvement over the Jobo made processors since it can handle a lot more chemicals then the processors are rated for. In inversion mode the smallest tank [the 2521] needs over 1 litre for just one reel. It only goes up.