Beseler 45 carriers and registration

[M Carter]

So the karma gods may have smiled on my search for a good deal on a 4x5 enlarger. Turns out a friend-of-a-friend has an absolutely pristine 45MXT, complete, looks like new, not some rusty garage-stored mess you see quite often. Seems like we'll find a fair price. Latest version with square bellows.

She doesn't have a glass carrier, so I found a deal on a box of carriers which included a double glass Beseler. I haven't seen the enlarger in person yet and haven't used the MXT. All the carriers I found have four locating pins on the bottom.

So, my question - are those pins accurate enough for masking? Do they return the neg to the exact place, or are they more in the horseshoes and hand-grenades zone?

If I come up with a pin-regsiter solution modding an existing carrier, will I need a more accurate way of registering the carrier itself? (I actually ghetto'd-up a glass carrier with registration for my 67C, so it's doable I suppose). Interested to hear any info from MXT users. (Hell, I'll read all the guesses, too!)

 

[John Koehrer]

Horseshoes more likely. They center the carrier on the negative stage but they can and will rotate.
There MAY be a bit of shift/play on any axis. It's been a loooong time.

 

[darkroommike]

Thinking out loud. Make a new carrier stage for your enlarger with two registration holes, modify one of your carriers to mount four pins, two on the bottom to mate with your new stage and two on the top for film registration.

 

[M Carter]

On my 67, I drilled two holes in the bottom of a neg carrier, and used that as a template to drill into the casting that holds the carrier. I made two threaded posts that go through the carrier, and ground the thread off where they stick into the casting. Very good & tight fit, but man... I kinda don't wanna take a drill to the 4x5. I believe Radeka & others make a registration carrier. Was hoping the stock pins were a registration fit though...

 

[grahamp]

The Beseler 45 negative stage clamps, but not so tight that the carrier cannot rotate (that's a feature) with the pins on the carrier riding inside the circular space in the lower negative stage. The 4x5 Negaflat does not rotate, but the design of the stage still allows some slack, and works against critical repositioning. Apart from installing registration pins in the lower stage and doing matching holes in every carrier I think you could make a metal insert that slides over the stage base with a grip for the handle on the carrier that would go on top of it. To achieve accurate registration would require some close tolerances or some springs.

 

[M Carter]

Seems like a good possibility would be to remove the pins from the bottom half of a spare neg carrier, add a tiny bit of taper to the tops of the holes where the pins used to be, and cut the window wider than 4x5... and then affix that to the neg-stage casting (outside of any rotational stuff). Maybe do it with tapped holes and flat machine screws so it could be removed. The holes for the pin-rivets in the carriers are a tight fit, so my guess is that then placing a regular neg carrier onto the adapted and fastened carrier would give a tight fit. That should make all carriers registered... in theory. Sounds pretty easy, I'll check it out when I get my hands on the enlarger.