de vere 504 varicon

[evdb]

dear friendly photographers

i am in the middle of installing my enlarger, but as it came with 2 heads i need to install it from scratch. The head i want to use is the 504 varicon but the screws, bits and bolts that came with it dont seem to make sense. So i was wondering if anyone who uses this 504 de vere with varicon head would by any chance have a close up picture of the back of the head to see how it attaches?

Also, the other head, a colour one i assume, connects through a big fan, presumably to keep the temperature down. However, the varicon head does not seem to have similar connections, does this mean the varicon does not need to be kept cool? because the bulb is less intense or the distance between the bulb and the neg is smaller? Or am i missing something and it does need a fan?

I have my fingers crossed. Thank you in advance

Evdb

[Phil Hudson]

The Varicon uses a mains voltage photocrescenta lamp, usually 150W. The condensers will absorb some of the heat radiated towards the negative, while some of it will rise up by convection and out of the top of the lamphouse (it is passively vented rather than fan cooled). Exposure times can be quite short because it is an efficient design......negative buckling might not be an issue.

The early 504 dichromat (Mk III I think) heads used a stand-alone blower delivering air to the lamps through a large duct rather than a pair of small balanced fans in the head itself (Mk IV and V). The stand alone blower solution eliminates any vibration issue that may occur if the fans in the head wear out and start to get out of balance.

The heads mount in the same way (sorry, no pics for you). Depending on the age of the 504 chassis there will be either a pair of silver L-shaped roller bearings sticking out the back of the CHASSIS (early) and there may/may not be a deep V-profile groove running vertically down the uppermost rear part of the chassis as well. The L-shaped roller bearings fit into the corresponding L-shaped slots in the back of each head. If the HEAD is a later type it will have protruding nylon wheel attachments at the rear which run in the V-shaped groove on the enlarger.

Before mounting the head make sure the two head-raising pins are in place on the chassis and slacken off the nylon trim screws on the chassis that may cause the head to bind. These will be readjusted later to ensure the head goes straight up/down. Offer up the head and guide the rollers into place. On early chassis/heads the L-shaped rollers run inside a slot in the head and on later ones the nylon wheels on the head simply run in the groove on the chassis. Finally hook the spring tab on the back of the chassis over the protruding screw on the back of the head (choose the appropriate tension). Check the raise/lower lever works and readjust the nylon guides so that with the carrier in place the head sits down square and flat onto the carrier.

They're great machines once you've got the hang of it!

[evdb]

thank you ever so much for your time and knowledge Phil. Not so worried about the fan any longer. As for the installment, i seem to have the L-shaped bolts, but they do not fit through the holes, which makes me think perhaps these belonged to another head or chassis. so I am going to try and find smaller bolts. I hope this wont too tricky.

Thanks again!

EvdB

[Nasir]

I've been given a De Vere 504 enlarger with a Varicon head but there's no power supply or timer. The lead from my Varicon has a kettle style plug on the end so I'm stumped about what I need to get this thing working. Do I need a dedicated power supply? What about the timer? Do I need something specific to this head?

Any help would be much appreciated.

[2014268]

I've been given a De Vere 504 enlarger with a Varicon head but there's no power supply or timer. The lead from my Varicon has a kettle style plug on the end so I'm stumped about what I need to get this thing working. Do I need a dedicated power supply? What about the timer? Do I need something specific to this head?

Any help would be much appreciated.

[2014268]

Hi Nasir,
Just plug the kettle style plug into the back of a timer (The back side of a timer has reciprocal socket with the word "ENLARGER"). The power supply came through the timer.
When you turn on the timer and press "PRINT", the opal lamp will light up.

boon
drbcng@gmail.com