Graflex Crown Graphic Rear Yoke Guide Installation Questions

**spacegoose** · 4-Sep-2023, 08:11

My rear yoke guides failed due to user error. I think they must have been a little loose and/or I tried to drop or close the front door when the rails were extended.

I'm wondering if these guides are meant to fail to protect other (more expensive) parts? Like the rails themselves or the threads for the guides, etc - due to being made of weaker material? Related, I'm wondering how I can know the rails are not damaged?

I've found some replacement guides on ebay and was told installing them is a bit fiddly. I noted my right guide had 1 shim and the left 2. The guides also have seating pins attached as well ... are these removable, in case my replacement guides are missing them?

The seller mentioned loosening both front and rear yoke guides to get the adjustment correct. Should all the guide screws (front and rear) be snug tight when final adjustment is complete?

Thanks for any yoke / guide adjustment advice!

**Dugan** · 4-Sep-2023, 08:38

The guides break because of the thin-ness of the material surrounding the groove...it's cast metal.
You can also turn the rear guides around, and put them on the other side.
Yes, it's fiddly.
The yoke is probably ok, unless it was really forced hard.
IIRC, the pins are removable/ replaceable.
The screws are supposed to be tight when you're done shimming them.

**spacegoose** · 4-Sep-2023, 10:22

Thanks for the info and thoughts about my yoke hopefully being undamaged!

Maybe the index pins are screwed into the guide bottoms?

Do you also loosen the front yoke guides when installing and adjusting rear guides?

I decided to wait for replacement guides instead of turning these around.

Mostly because removing the bellows from the rear is something I only want to do once, or as few times as possible.

It seems reversing the guides may leave them weaker than an undamaged set?

I saw these: https://www.graflexparts.com/products/carriageguides - which seem a bit pricey! I wonder if they (being brass) may also be too strong to fail when they should, assuming the original cast metal guides are meant to fail to protect other components? Edit: According to the description at https://www.graflexparts.com/products/carriageguides - carriage guides were sacrificial pieces. I would guess the ones on offer there are as well, though it doesn't specify for sure.

I followed instructions here: https://lommen9.home.xs4all.nl/broke...des/index.html

to remove the bellows and noticed mine did not have the 2 moving clips mentioned. Mine only have the 8 clip tabs mentioned.

I started by push unseating one tab, with the help of an appropriately sized flat head screwdriver and my fingers; and then finger pushing the rest in. It seemed like a bit of a risky operation, prone to possibly damaging the tabs, etc.

I also found removing the shutter actuator assembly from the front standard to be difficult.

The thumb wheel seemed locked on. The link mentions a small clip or retaining ring on the thread end but I couldn't see one, even with a loupe.

It doesn't seem necessary to remove the shutter actuator assembly from the standard to work on the rear yoke guides - though I can see how it might make things easier to get the bellows completely off the camera.

My bellows are currently being held on by the shutter actuator assembly's cable - which I can't seem to figure out how to snake under the bellow bottom's wire retainers (the shutter actuator assembly doesn't clear them).

To remove the actuator from the standard, I ended up force turning the thumb wheel left, until it came off, but in doing so, I slightly deformed the post's flat head screw head. I may have also damaged it using a screw driver.

The post the thumb wheel (nut) screws down onto seems like it's a screw; is it? Or is it a post not meant to be screwed?

Thanks!

**Dugan** · 4-Sep-2023, 11:49

If you are referring to the knurled tilt adjustment nuts, and the posts those are screwed onto...those posts are staked, that is not a flathead screwdriver slot. It is that way to prevent loss of the knurled nuts.
Sorry, I can't help with the shutter actuator cable, first thing I did when I stripped down my SG to be a field camera was to get rid of all the rangefinder/viewfinder doodads and everything else deemed unnecessary for my purposes.

**spacegoose** · 5-Sep-2023, 10:47

Thanks for that info re: the staked posts.

I was referring to the top right adjustment nut (the one that holds the shutter actuator assembly). I wonder if there is a proper way to remove the nut (and thus the shutter actuator assembly) - or is it meant to be permanently attached?

I see the value in removing the extraneous bits in favor of only ground glass focusing, which I plan to do 99.9% (if not 100%) of the time, a significant part of me wants to keep the camera complete.

**Dan Fromm** · 5-Sep-2023, 13:17

I can't speak for 4x5 Pacemaker Graphics, but I have several 2x3s. I've removed the front shutter actuator assembly from all of them. It isn't necessary, really. The thumb screw that retains the assembly is really there to lock front rise. It is indeed staked, but can be unscrewed off without hurting anything and then screwed back on.

Reaching inside the box to remove the body end of the front shutter actuating cable is a pain, can be done.

Go for it!