Repair Broken Rear Guides.
The fact that you've been linked to this page means that one or both of the rear guides of your camera are broken.
Broken rear guides make it impossible to turn the yoke or track anymore for focusing movements for and backwards.
The guides were made from die cast molding and thus very breakable. You can't repair this material but this page will show you how we can make the yoke track to function again.
As you can see on the pictures below it is mostly the upper side of the rear guide which is completely or partly broken. Most of the time in such a way that the guide lost its function and the yoke case section can't be guided anymore between both rear guides.
Once derailed the yoke case section cannot be moved for or backwards by using the focusing knobs on the front of the bed.
Focusing becomes impossible. Your camera can't be used anymore!
First remove the Bellows and Standard.
Let's see how it looks when the guides are broken. To get a good look at it, the lens standard should be unlocked and pulled to the front and raise the lens standard to get a better view into the back of the camera housing. However, to get a real good look and to be able to work on it, the bellows should be removed as well as the lens standard.
First remove the screws of the back of the camera - two on top and three on the bottom side and one on the lower part on the right side. Remove the camera back. It should come off easily. Open the focal plane shutter (Speed Graphic only) to be able to get access to the inner of the camera housing.
After having removed the back of the camera, you can see two clips holding the back of the bellows firmly to the camera frame, one on the upper side and one on the lower side.
Remove these two clips by sliding them a bit to the center of the frame.
Further you can see 8 clips connecting the back of the bellows to the frame. Place a screwdriver between the frame and one of the clips. Turn the screw driver in such a way that the clip comes off the frame. The other 7 will come off with a little help of your fingers. Be careful not to damage the bellows.
Remove the release assembly on the right side of the lens standard by unscrewing the thumb wheel. Note: sometimes you can remove the screw without any problem. Sometimes however the screw will stuck on the end of the thread. Using a magnifier you can see a very tiny ring retainer on top of the thread. Remove this 1 mm big thing using a needle or something small like that. Once the little retainer has been removed the knob can be turned off easily. Pull the standard including the bellows from the yoke and put it apart. Now you have easy access to both of the rear guides.
Repair of the Broken Rear Guides.
The rear guides normally use to break on the front side. Not always completely but just half way. If that is the case, repair will be easy.
Just exchange the left guide with the right one and the rear guides catch the yoke case section without any problem.
Photos below show the new situation. Although not completely guided, focusing should work again without any problem.
Now the yoke case section will be properly guided in the rear guide and no further action is needed.
However, sometimes it will be necessary to put shims under the rear guides to get them on the same level as the front guides.
On the other hand, if the rear guide is broken over the full length, focusing will be soon impossible.
The red arrow points to the broken part of the guide.
This photo shows how the yoke case section of the track derails out of the broken guides and thus making focusing impossible anymore.
I found a cheap, reliable and really simple way to make it work again.
Making a cover.
You need a steel dark slide of a 4x5 film holder.
These holders can often be purchased on a flee market or on a camera fair. Further more a pair of scissors for general use and suitable for cutting tin steel.
Most household general purpose scissors would do.
Cut a piece of steel out of the dark slide of 44 x 19 mm and follow the photo instruction below.
The piece of steel should be bent in the right angle to serve as a cover around the broken guide.
The photo in the middle shows that the guide cover on the upper side is just one millimeter over the edge. Quite enough to hold the yoke in position.
The next photo shows the drilling of two corresponding holes for final mounting.
The new cover should be pushed over the broken guide as shown on the photo. Once in the right position the screws can be tightened and the guide is completely capable to work for a lifetime.
If any questions please use my feed back form.
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