HELP: Graflex RB Series D - Tension Spring Problem

[fstop760]

I picked up a Graflex RB Series D, yesterday. I shot a bunch of tests shots (http://imgur.com/a/oGLR0) with it using different exposure combinations (slits and spring tension).

Everything was fine. I got home and dropped the spring tension down from 5 to 1 and now it won't go back up.

The knob spins but the number doesn't move at all.

The focal plane shutter still works

Any ideas what the problem might be?

[Jim C.]

The numbers are stamped onto a large gear that engages a pawl , the knob of the Tension Plate
is peened in place so I've never taken the assembly apart.
Does it click or engage when you turn the tension knob, and can you still release the tension
using the tension release button ?
133510 133511

[fstop760]

No click or tension. Here's a video link to the issue: https://vid.me/NPdF

The release button worked. That's how I got it from 5 to 1 the other day. It stopped winding after that

[Jim C.]

Looking at you video is does seem like the knob has detached from the gear, you'll either going to
have a get a beater for parts or take the Tensioning Plate off to see if the knob has detached.

If you're brave enough, you can remove the Tensioning Plate to see what's going on inside, note that
removing it will release any tension in the spring inside the lower curtain roller. So if there is any tension
set on the curtain it should be released past O, if it's still possible.

[Jason Greenberg Motamedi]

I think Jim is correct. The knob is no longer attached to the shaft or gear. You will need to take off the mechanism and see what broke. It is relatively easy to remove, although as Jim notes it releases all tension on the spring, so can be a little difficult to replace. I am sure there are instructions how to do this somewhere online.

The good news is that you didn't break the main spring.

[Louis Pacilla]

You can get a lot of great Graflex help if go to Graflex.Org and ask this question on the "Help Board".

http://www.graflex.org/

[EdSawyer]

here's some info I had saved about retensioning the shutter (which you will have to do after releasing tension and removing the knob), so this should be helpful.

--------------------


About servicing Graflex focal plane shutters

FROM: w1xyz@aol.com (W1xyz)
SUBJECT: Tensioning the Graflex Shutter - repost
DATE: 11 May 1999 22:37:32 GMT
ORGANIZATION: AOL http://www.aol.com
NEWSGROUPS: rec.photo.equipment.large-format

here it is



Tensioning the Graflex Shutter


This How To is for those who recognize that the rewards of learning how to "do
it yourself " must be weighed against the risk of potential failure. Don't
risk ruining your Super D if you aren't sure ! ;-D

INTRO

By now the old and venerable spring in your RB auto Graflex or Series D has
lost its luster and doesn't pull the curtain fast enough. As a result, all
speeds are slow. Fortunately the fix is not too difficult for those with a
little patience and mechanical aptitude:

PROCEDURE

1. First make sure that the curtain is not rubbing anywhere and the curtain
selector is free to move (they often get bumped and then stick). It should move
very freely with no sticky spots.

2. Apply just a drop of lightweight oil into the two oil holes. These are the
little holes in the end of a round, flat, keyed metal piece on the left hand
side of the camera. Don't ever use or spray WD-40 or any spray lube or it'll
get in and mess up the works. Just use one of those little needle oilers like
the one sold in Radio Shack. Check to see if this improves things dramatically
- probably not ;-)

3. Look at the tensioning escutcheon (that's the plate that surrounds and
holds the tensioner) You'll see the tension knob, the release button and a hex
shaped cap. You should also see screws at the perimeter of the plate-don't
undo these yet. Release tension with the release button now. Then just take off
the hex cap (counterclockwise) to reveal the screw slot.

4. Find the right screwdriver to fit the screw slot before proceeding. Notice
that as you tension the shutter, the screw slot rotates. This slot is at the
end of the tensioning shaft and has to be tightened in order to increase the
spring tension. Don't try to force the screw since it's locked in place
relative to a gear under the plate.

5. Loosen, but don't remove, the screws holding the plate down. On the Series
D there are four screws. The idea here is to lift up the plate enough so that
the gear disengages from the shaft so that you can retension it. Put a thin
screwdriver in to hold the slot BEFORE you lift up the plate so that the
tension doesn't release suddenly.

6. You may have to unscrew the perimeter screws a little more to disengage the
gear. Once accomplished, now is the time to guess how much more tension to
apply by turning the slot so that it gets tighter. I'm impatient so I give it
a good whirl thereby throwing caution to the wind. This can result in too much
tension which could overly stress the now ancient shutter curtain material, so
you probably should try moderate tensioning first. If the spring has lost its
temper, it will feel "dead" when you turn the screw - this is not the case and
the spring has some life left in it.

7. While still holding the tensioning slot push the plate back down to engage
the gear. Re-tighten the perimeter screws. Put the hex cap back on after
applying one drop of oil.

8. Test the shutter. I usually test with Polaroid having found the speed to
be reliable enough, however, if you have a flash meter you could make a setup
with a bright light to measure the relative shutter speeds.

9. You may have to go back and do this again. Be patient, don't poke or pull
on the curtain in frustration, and don't curse me 'cause it's really easy and
self evident once you dive in.

FINAL COMMENTS

I love these old boxes and with care they ought to be useful tools for the
serious photographer. I am still learning the ins and outs so I don't claim to
be an expert by any means but I have found this procedure to be workable
several times now with no failures yet.

PS - I've been asking around about how to convert some of these to Graflok
backs, a challenge that I have not attempted yet but will tell you about my
experiences and write a "how to" if there is any interest.

Bob Crowley





FROM: dickburk@ix.netcom.com (Richard Knoppow)
SUBJECT: Re: Tensioning the Graflex Shutter - repost
DATE: Tue, 11 May 1999 23:38:27 GMT
ORGANIZATION: Netcom
NEWSGROUPS: rec.photo.equipment.large-format

I've found in some Speed Graphic and Graflex shutters that the
lubricant in the shutter roller has gummed up. A small amount of light
oil there will loosen it up and increase the speed. The rollers for
the shutter curtain may also need just a touch of oil on their
bearings.
Most older Speed Graphics seem to have had the tension cranked way
up to get the highest speed to be really 1/1000th. It makes the slower
speeds much too fast.
Accuracy of speed is not the strong point of the older shutter
design. The modified shutters in the Pacemaker Speed Graphic and in
the Super-D Graflex are much better.
---
Richard Knoppow
Los Angeles, Ca.
dickburk@ix.netcom.com

[Jim Noel]

I prefer to use "Drop-L-Do It" from Lubecon. It is molybdenum suspended in a quickly evaporating carrier. It never gums up and is the lubricant recommended for Leica shutters.

[Tin Can]

I have cans of spray Moly, but it's clumsy for cameras...

I use it less than my Nuclear Grade anti seize, which is also a real product.

I just bought clock oil from Otto Frei http://www.ofrei.com/page246.html