Question on adjusting a Maxwell Screen to fit a new camera

[StuartR]

Hi everyone,

I wrote an email to Bill Maxwell about this and am still waiting for a response, but I figured I would ask the hive mind here for advice as well. I have a Hi-Lux screen that I bought in 2004 or 2005 for my monorail camera. Nowadays I mostly use my Ebony. I have the stock screen in the Ebony, and I find the Maxwell to be much better. I would have switched them right away, but the Maxwell screen was made for a Horseman 45LE, and unfortunately it is every so slightly wider, so it will not fit in the Ebony. With my caliper, it tells me that the Horseman screen is about 100.8mm wide, while the Ebony screen is 99.63mm wide. So, the Horseman screen could take about 1.2mm off, and it would fit the Ebony. I think it would not even affect its use on the Horseman, as there seems to be fairly ample room on each side supporting it. In terms of cover glass, I could just use the Ebony glass, as it is just a plain protective glass that already fits. Since the Maxwell screen is plastic, I assume it is not overly difficult to cut or sand, but it is not something I have experience with, so I figured I would ask. I live in Iceland, so sending it out to the US and back again is costly and time consuming. If this is something I can do fairly easily with sand paper or even a dremel, I might risk it. I did not want to do so until I had heard from people with more familiarity. I understand the screens and the fresnel markings are liable to be very fragile, so obviously care would need to be taken...

Any thoughts?

[Ari]

I've done this with a regular glass screen, it was less than 1mm too long, so I took sandpaper to it. Coarse first, then fine.
It takes a long time, but it's very do-able.
Having never done this to plastic, I can't tell you what to expect, only that I hope Mr Maxwell has been in touch by now.

[StuartR]

Hi Ari,
Yes, he called and we spoke for two hours, which is a little longer than usual with Bill, but not by much, haha. He wants to do it himself, but said he would tell me how to do it if I wanted to do it myself, but did not actually tell me. He said they were extremely delicate, and advised against doing it myself in that if I made a mistake, I would potentially be out the cost of the screen. I may just send it to him, as my screen is old enough that he could also upgrade it, which might be interesting. Still, I cannot imagine that resizing it would be rocket science...I imagine that the plastic is similar to acrylic and soft enough that it would likely work with just a piece of medium grit wet sandpaper on a piece of glass for flatness, using distilled water as a lubricant. Maybe 180 grit to start and 400+ for a final polish.

[Bob Salomon]

Hi Ari,
Yes, he called and we spoke for two hours, which is a little longer than usual with Bill, but not by much, haha. He wants to do it himself, but said he would tell me how to do it if I wanted to do it myself, but did not actually tell me. He said they were extremely delicate, and advised against doing it myself in that if I made a mistake, I would potentially be out the cost of the screen. I may just send it to him, as my screen is old enough that he could also upgrade it, which might be interesting. Still, I cannot imagine that resizing it would be rocket science...I imagine that the plastic is similar to acrylic and soft enough that it would likely work with just a piece of medium grit wet sandpaper on a piece of glass for flatness, using distilled water as a lubricant. Maybe 180 grit to start and 400+ for a final polish.

Isn’t there a plastic supply shop somewhere in Iceland? They should be able to properly resize it in a few minutes or, if not, sell you what you need and instruct you how to do it yourself!

[StuartR]

Hi Bob,
I am not aware of a place that would be familiar with handling something as delicate as a focusing screen, though there may be one around that I am not aware of. There is a shop that sells acrylic and so on, and I could ask there, but I do not think they are used to working on precision components. This is a country the size of a small city, and while they have pretty much everything, stuff like this which is fairly specialized is often ordered from Germany, Scandinavia or the US. My most sensible options are to do it myself, or send it to Bill.

[Bob Salomon]

Hi Bob,
I am not aware of a place that would be familiar with handling something as delicate as a focusing screen, though there may be one around that I am not aware of. There is a shop that sells acrylic and so on, and I could ask there, but I do not think they are used to working on precision components. This is a country the size of a small city, and while they have pretty much everything, stuff like this which is fairly specialized is often ordered from Germany, Scandinavia or the US. My most sensible options are to do it myself, or send it to Bill.

Acrylic is acrylic, all you need do is explain to them that you want to maintain the center on the new size and that the grooves are delicate. They can handle the trimming.

[rfesk]

Well, I say emphatically - send it to Bill. That screen is extremely delicate. taking 1mm or so is not hard. Messing the screen up is very, very easy. An acrylic shop has no idea how delicate it is - regardless of what you tell them.

Bill says you can blow on the screen gently to get dust off but don't try to clean it an any other way. (I have an old Maxwell screen I switched from a Busch Pressman to a Sinar.)

[Bob Salomon]

Well, I say emphatically - send it to Bill. That screen is extremely delicate. taking 1mm or so is not hard. Messing the screen up is very, very easy. An acrylic shop has no idea how delicate it is - regardless of what you tell them.

Bill says you can blow on the screen gently to get dust off but don't try to clean it an any other way. (I have an old Maxwell screen I switched from a Busch Pressman to a Sinar.)
Of course they do, if you tell them it is. Grinding a small amount of each side is very simple for a plastic shop. And they can always cover both sides if requested!

[consummate_fritterer]

When I bought a Maxwell screen for a Chamonix 45N-1, Mr. Maxwell suggested I send the camera and screen to a specific technician. I'm sorry, I can't remember the tech's name.

[DennisD]

Maxwell screens are delicate and expensive.

Before Letting any shop or anybody adjust or trim a maxwell screen, I'd make certain they and their equipment are capable of handling delicate material and working at fine tolerances.

OTOH, If the screen is not in great condition, one might be willing to take greater risks.

.