Counterbalance springs for enlargers -- Source found

[Vaughn]

Having 13 Omega D5-XL's to maintain, parts can be troublesome to find -- even though the enlarger is still in production. A call to the main supplier of Omega parts told me that the counterbalance springs are not in stock, and Omega does not know when they will be available. The supplier did have a couple of the counterbalances that have been refurbished for $99 each.

At this price, one might as well buy a used enlarger for $100 and save that much again by stripping it of the parts.

I contacted the Pullman Manufacturing Corp in Rochester, NY, and they made me a couple of the counterbalances for $65 each (and I have ordered 4 more to have on hand). The counterbalances installed and work perfectly. So if you need one or more, you can contact them. It is not on their website, but they'll know what you are talking about.

Contact info:

balancesales@pullmanmfg.com or call customer service at 585-334-1350 x302.

http://www.pullmanbalances.com/

Vaughn

 

[Wade D]

Nice find. Although not originally for enlargers, I found that balance springs for old wooden sash windows will work. It's a chore to find them but they are available in various weights that they will support/balance. Not as elegant as the proper devices but they will work in a pinch.

 

[Ian C]

Pullman sash counterbalances are original equipment on certain (but not all) Omega enlargers. The ones on my DII are marked “Pullman” on the base plate. They’re finished in the same flat black as the other components and are apparently original.

 

[Vaughn]

I had sent Pullman a broken counterbalance from the D5 and they said it was not theirs. But basically it is a window sash counterbalance set up to attach easily to the enlarger, and built to support the same weight (for the D5 it is 14 lbs for each counterbalance).

 

[Leigh B]

McMaster-Carr Supply Co at www.mcmaster.com has a huge assortment of springs.
They probably have one very close to your requirement, for much less money.

Springs are among the simplest mechanical parts to fabricate, so it's quite common for OEMs to design springs exactly for a given purpose and have them made to order.

For example, they have a variety of "safety extension springs", like this:

at ratings to over 300 pounds at less than $30 each.

- Leigh

 

[Vaughn]

Did not see anything close at McMaster-Carr -- and what was perhaps adaptable (with a lot of work) was twice the price.

 

[Neal]

Dear Leigh B,

The two items are not interchangeable. The couterbalance supplies a surprisingly constant load over a long stroke. For the spring to be truly effective you would need one that is quite long. Still, if you have the space and are mechanically inclined it could work.

Neal Wydra

 

[brucemuir]

Do you guys know if it is advantageous for counter spring life to store the head in a specific position while not in use?

 

[Ian C]

Like all springs, these last longer if not kept overly compressed. To that end it’s prudent to keep the head somewhere in its upper 1/3rd of travel when not in use, preferably most of the way up to relax the spring as much as possible. Think of Mamiya’s recommendation to store its lenses uncocked if not to be used for a while.

Most of the counterbalance spring failures I’ve seen were due to using the head in very low positions. That overly compresses the spring and might weaken or eventually break it. I’ve long followed the practice of raising the easel on boxes instead of dropping the head a great deal when making small prints.

 

[Vaughn]

Do you guys know if it is advantageous for counter spring life to store the head in a specific position while not in use?

Like Ian, I have found that keeping the enlarger head down all the way with the D5-XL increases the chance of the spring breaking. Usually the band breaks inside the casing. I keep ours at about the 50 mark...a little less than halfway up. One of our instructors wanted me to keep the enlargers low so that shorter students would have an easier time using them (she was short, too). But we started to break CBSs right and left -- and this was when they were still readily available at $25 each!

I never had a counterbalance spring break on the Beseler 23C's. Way too hefty of a spring to ever break. We have 8 of these enlargers and I have had no spring break in over 20 years.

The counterbalance springs (CBS) are designed to hold a certain weight -- too strong and the head will rise, too weak and the head will fall. The D5-XL's are designed to hold 14 pounds each (two CBSs per enlarger). Until I could find some CBSs, I ran two of the D5's with only one spring each. A bit of a hassle, but the hold-down screws could keep them in place -- but they would not hold at a height without the screws.

Harry, the expert Omega guy, did recommend spraying WD-40 inside the CBS to keep it young and healthy. So that and keeping the enlargers stored at mid-height, should keep the CBS from breaking. I would not worry about using the enlarger at its lowest height, but I just would not store it there. But I now have 6 CBSs in stock (2 here, 4 on the way) not including the two I just installed, so I should be covered for a long time.

Vaughn