Brumberger (5 x 7) Contact Printer

[Kevin J. Kolosky]

I purchased one today in mint condition for next to nothing and would like to use it. But it did not come with bulbs.
I looked at a short video on U-Tube about the use of the machine. That one had two cords coming out of it. One that turned on a red bulb, and one for the white bulbs. Mine came with only one cord so I would imagine the red bulb would stay on all of the time once I plugged in the cord.

Questions

were there different models with some having two chords and some having only one, or is it possible that someone just rewired theirs and added the extra cord.

are there specific bulbs that must be used. if so where could they be purchased from.

Thank you.

[LabRat]

Interesting, as I just restored an old Aeroquipt 4X5 contact printer last week for proofing duty... Mine had a 15W bulb the size you find in old ovens and fridges, and a 15W ruby bulb for the safelight... The bulbs were about 5" away from the milk glass diffuser...

The first test I did was to see how even the illumination was, and not bad, but about a 1/3 stop under near one edge... I noticed that because there was 2 bulbs inside, they had to be placed staggered so they both would fit, but that meant the white light bulb was not centered under the diffuser, so I made a new lamp bracket that would center, and with a sliding slot for it so if I used different height bulbs, I could keep them centered... I realized that the safelight was not really needed in a standard darkroom, as the lamp could be turned on to center the neg, then paper could be pulled out and placed in the dark...

It had a switch that turned on the lamp when the cover was closed, but that was not needed as I was going to use an enlarging timer with it, so I removed it...

For good luck, I removed everything from the bottom chamber and sprayed the bottom with flat white spray paint, and white'ed out everything inside... I didn't want to mask the top half of the inside printer (to spray paint it), so I cut some very thin white mattboard to line the top half, and hot glued them in...

I tested this the other night with some very old MGRC I had a large box of (to get rid of), and with the 15W bulb/norm negs, the exposure time was 3/10th of a second, so that bulb was very bright for modern (old) paper... + or - 1/10 second was like +/- 1 stop, so the bulb was WAY to bright for any fine control of exposure, so I picked up one of those 7 1/2W golf ball sized bulbs hoping to get the exposure nearer to 1 second so I could trim the exposure by tenths of a second... I had some old Kodak PC acetate large MG filters I could cut down for the diffuser if I used MG paper...

The proofs came out great, with the flat paper, held highlights well, and had just enough of a warm (real) black to look like a real print (but old world), and very pleasant to look at proofs... DWFB/MG would look nice too, but didn't try it yet... Old Azo would probably like a brighter bulb, but the wattage of the lamp should be low for normal papers, as these seem to pump a lot of light to the paper...

One tip I found on the fly was it is a little hard to lift the neg off the masking blades on top, but I happened to have a bamboo round chopstick (with it's tip sharpened in a pencil sharpener) laying around nearby, and found it GREAT to push the neg around on top, and help lift the neg off when finished...

Good luck with it!!!

Steve K

[LabRat]

I was using mine this weekend, and I thought of something...

Since yours is the 5X7 model, the bulb might also need to be longer to cover the added size of the 5X7 diffuser, so check if there is the space for one of those longer frosted picture frame light bulbs, as these might have been used stock with it...

Measure, and stop in the home store lighting department and see what you find... (I still think the lowest wattage bulb is barely passable with modern paper speed, and I think these printers were intended to print with the slowest papers, like Azo...)

Steve K

[Charlie Strack]

Just a word of caution: the ruby bulbs used in these might not be filtered enough by the paint to eliminate all wavelengths that could expose the paper, especially multi-contrast. A separate switch for the red bulb (or cord) is a good idea.

[Jim Noel]

I was using mine this weekend, and I thought of something...

Since yours is the 5X7 model, the bulb might also need to be longer to cover the added size of the 5X7 diffuser, so check if there is the space for one of those longer frosted picture frame light bulbs, as these might have been used stock with it...

Measure, and stop in the home store lighting department and see what you find... (I still think the lowest wattage bulb is barely passable with modern paper speed, and I think these printers were intended to print with the slowest papers, like Azo...)

Steve K

You are correct - the printers were made to use with silver chloride contact papers like Azo and Velox. Silver chloride papers are several stops slower than the slowest enlarging papers. They use small round 5-7.5 watt bulbs , not long ones. Usually if they were made for 5x7 and had the original opal glass diffusers they worked beautifully. I have an old Ansco 8x10 which uses 4 bulbs for exposing the paper.