U of S | Mailing List Archive | alt-photo-process-l | Re: Speed Graphic Ground Glass Repair

Re: Speed Graphic Ground Glass Repair

----- Original Message ----- From: "Gordon Cooper" <nwlorax@comcast.net>
To: <alt-photo-process-l@usask.ca>
Sent: Sunday, October 26, 2008 2:39 PM
Subject: Re: Speed Graphic Ground Glass Repair

I need to replace the ground glass in my spring back Anniversary Speed Graphic in 4x5.

What is the correct procedure? I've removed the screws on the viewing hood to get to the ground glass, but can't get the metal bits on top of the frame that holds the ground glass. Not wanting to break anything, I thought I'd ask here.


Gordon Cooper
Bremerton, WA

The ground glass is held in place by two strips, one at each side. These strips also hold the sides of the viewing hood in place. Remove the screws on each side being careful not to let the spring loaded cover fly up. Once the screws are out the strips will come off and the old glass can be removed. The gound glass reference surface is the frame of the back so there is no adjustment necessary. The new glass just drops in. Replace the strips with the hood edges against the glass and fasten the screws. Make sure the new ground glass is solidly against the frame surfaces.
You will need to cut the corners off the ground glass for it to fit. The corners are supposed to be cut out to allow air to escape while extending the bellows but I think the real reason is to allow looking at the back of the lens to make sure there is no vignetting. The replacement glass may already have the corners trimmed.
If you need to cut glass precisely use a carbide scribe, not a glass cutter. Scribes are not expensive and can be gotten at most hardware stores. I got one at Home Depot so they are not too arcane a tool:-)

Richard Knoppow
Los Angeles, CA, USA