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Bill, 70's military B&W
11-Nov-2012, 15:24
I just mounted several lenses on to Linhof Tech lens boards,and now when I try and attach a few of them to the camera I find that it is too tight. The bottom of the lens prevents the lens board from fitting into the camera. The lens needs to be about ??1/8?? inch further out from the lens board. A fast and easy fix would be to cut a circle in a piece of cork, to just fit over the barrel of the lens, trim the outside to fit the lens and I'd have a spacer.
How has everyone else handled this problem?

I just learned that I'm going to have to rotate the lenses probably about 45* so that I can read the f/stop and shutter speed easier. Again how does everyone else do it?

Bill

Leigh
11-Nov-2012, 15:59
Cork is a very poor choice. It disintegrates easily and spreads little pieces all over the place.

You can find shim stock at any automotive store. Easy to cut with scissors.
Use multiple thicknesses if necessary.

- Leigh

IanG
11-Nov-2012, 16:19
Have you looked for the locating screws which many lenses have. You just file a goove in the board to accept it.

If you do need shims go to a garage you know they'll be able to help :D and cheap :)

Ian

Bill, 70's military B&W
11-Nov-2012, 16:50
Thanks guys, shim stock at a parts store, sounds great! I like the idea of metal.
Does the shim stock come big enough to fit around the lens? Or is it a wedge here and a wedge there?
I'll look for the locating screws, do these anchor the lens so that they do not rotate? Or do they act like a spacer, to help me in moving the lens forward?
Bill

Leigh
11-Nov-2012, 16:51
Shim stock is sold in rolls or sheets, as large as you might want. Certainly much larger than a lensboard.

It's also available in many different types of metals and plastics.
The plastic types are easier to cut and handle, but they're color coded by thickness, so you can't really choose a color.

With metals you certainly want to select a type that's not going to rust. Bronze, brass, or stainless steel are good.


I'll look for the locating screws, do these anchor the lens so that they do not rotate? Or do they act like a spacer, to help me in moving the lens forward?
The anti-rotation screw (on the back of the shutter at 12 oclock) prevents the lens from rotating in the lensboard.
It fits in a clearance hole or notch above the large hole. If the lens rotates in the board the ring can come loose.
I always use them when mounting a lens. Some folks prefer not to.

The screw is quite small (1/16" dia) with a narrow slot. If one is present and you don't choose to make a notch
for it, unscrew it with a jeweler's screwdriver and mail it to me. :D

The only Copal shutters that have spacers are the #3 size. Smaller ones do not. I don't know about other brands.


- Leigh

ic-racer
12-Nov-2012, 07:11
Cork will compress and loosen with time. You don't say what size hole, but these metal washers are Copal-0 sized are commonly available at a hardware store. They are for downsizing holes in electrical conduit boxes to get out of trouble when you punch out a the too-big hole.

However, it is odd the shutter binds on the camera, are you using correct "Linhof Brand" boards with the offset hole?

http://img.photobucket.com/albums/v670/ic-racer/washers.jpg

Jim Graves
12-Nov-2012, 11:32
Poster board ... and even foam board ... work well. It is cheap and easy to cut.

If you're worried about compression use the poster board ... but I've mounted some fairly large lenses using foam board as a shim without issue ... just tighten it down good when mounting. I tried it the first time just to get a quick mount with plans to replace it later. I was surprised how tight and stable it was and have never replaced the first one and have used it on other lenses since. In fact, I think some compression is desirable because the material forms to the lens and board surfaces and ensures a light-tight seal.

Because the only portions that are exposed are the edges you can use a black sharpie to color them.

Bill, 70's military B&W
12-Nov-2012, 18:43
Leigh,
I think I'd have trouble cutting hard metals. Yes I could use a Saber saw, but I do not think the results would be all that great. Plastic would not harm anything. I'll go to the auto supply store and see what they have.
I'll look for the anti-rotation screws, sounds like a great idea. I've already had a lens or two come loose. After shooting a few shots, I learned that I will want to rotate the shutter probably about 45* so that I can read the speeds and f/stops better.

You mention spacers for #3 Copal shutters??? Is this something I can buy? From where?
Thanks, Bill

Bill, 70's military B&W
12-Nov-2012, 18:53
Ic-racer, I bought these boards from China. I wanted them center drilled so I did not order the 'off center' ones.
Then I read where Bob S. said that Linhof drills it's regular ones a little below center, and the 'off center' ones are actually center drilled...... Damn!!!

The problem is located where the bottom of the Chinese Linhof Tech lens board slips into the adapter that I put on the cameras so that they will all accept the Linhof boards. The 3 or so prongs that stick up do not fit in the space between the lens board and the lens. Needs a spacer.

The size that is giving me trouble is Copal #3. I'll remember the metal washers from the electrical boxes. Heck, I'll probably take the lens down to Ace Hardware and HD and see if I can find something off the shelf that will work.

Bill, 70's military B&W
12-Nov-2012, 18:57
Jim, now that is an idea I can do right away. If I can't find something at the hardware store or automotive parts store then I'll give your idea a whirl. I've got some black poster board that will work just fine.

All you folks are wonderful, great ideas. Obviously there is more than one way to do things.

Thanks to all,
Bill

Michael Clark
12-Nov-2012, 20:45
Excuse me for changing the OP subject, but the spacer ring on the #3 copal, is that only for the spacing for the thickness of the lens board and not the spacing of the cells ?

Mike

ic-racer
13-Nov-2012, 07:38
The size that is giving me trouble is Copal #3.

Copal #3 can be tough to fit on a Technica board. Here is one I did, the hole had to be just in the correct place so the lensboad keeper didn't bind.

http://img.photobucket.com/albums/v670/ic-racer/2012/mounting2.jpg
http://img.photobucket.com/albums/v670/ic-racer/mounting8.jpg

Bill, 70's military B&W
13-Nov-2012, 19:14
ic-racer, the lens boards I bought came predrilled from China. The hole is slightly lower than center. Maybe the answer for me is to buy a couple of boards and this time buy the
"off center" boards, that in reality have the holes drilled in the center. I believe that would solve the problem by raising the lens up slightly and thus avoiding the bind at the bottom.
I think that would solve all my problems, unless I missed something.

It is confusing, and I made a mistake. When I bought the lens boards I had a choice between standard or off center boards. I did not want the lens to be mounted low in the lens board so I bought the standard boards. When they arrived I noticed that the holes were drilled lower than center. I looked around and Bob S. explained that that is the way Linhof drills their boards.

So I think a couple of 'off center' boards, actually drilled in the center of the board, will raise my lens and avoid the bind at the bottom.

Am I right?
Bill

Bill, 70's military B&W
13-Nov-2012, 19:21
ic-racer
And I forgot to add, that is one beautiful camera, and from what I've read that is a wonderful lens.
I'll trade you a 8x10 Grover for it. I'll throw in a folding 8x10 Grover too!!! Heck to sweeten the deal I'll include a 5x7 Grover, my dog, my cat, and I'll cut your lawn.
Bill

ic-racer
13-Nov-2012, 19:40
ic-racer
And I forgot to add, that is one beautiful camera, and from what I've read that is a wonderful lens.
I'll trade you a 8x10 Grover for it. I'll throw in a folding 8x10 Grover too!!! Heck to sweeten the deal I'll include a 5x7 Grover, my dog, my cat, and I'll cut your lawn.
Bill

Actually that camera was less than $2000 new when I got it, but I see the price has risen above $2000 now. Between you and me, that lens is not as good in the corners as the 80 degree coverage Fujinon 210mm.

In terms of making a lensboard hole, if you have a drill and a dremel or a file it is not too bad. The day that lens came in the mail I was shooting with it in less than an hour. A little work with the drill, dremel and a file and I was good to go! My 'tip of the day' is that I make the mark for the hole bigger than I want, that way I don't grind and file away the mark as I get up to it.
http://img.photobucket.com/albums/v670/ic-racer/2012/mounting4.jpg

http://img.photobucket.com/albums/v670/ic-racer/2012/Mounting5.jpg
http://img.photobucket.com/albums/v670/ic-racer/2012/mounting6.jpg

Bill, 70's military B&W
13-Nov-2012, 20:00
ic-racer,
Glad to hear you say good things about the Fuji 210, because that is the one I have.
That was some nice work on the lens board, you are pretty resourceful, I'll mentally file that trick away, might need it.
Do they make bits for routers that will work on metal? I have a router table and could easily do something like that, if I had a metal cutting bit.
Bill

uphereinmytree
13-Nov-2012, 20:05
I happen to like cork, but you need the thick pressed kind used for gaskets. You can get a gasket material sample pack from Napa auto parts store including cork and other cool materials to be used for all kinds of photographic applications

BrianShaw
14-Nov-2012, 07:32
I happen to like cork, but you need the thick pressed kind used for gaskets.

Cork is a classic gasket/spacer material and has proved itself over the years. As you say, there is cork... and there is gasket cork. There is also wine/champagne bottle cork too. :)

Bill, 70's military B&W
18-Nov-2012, 21:16
I found a solution!!! Cheap, readily available, easy to do, looks like it belongs there, and it keeps the lens from rotating.
Any plumbing or hardware store will have a "Tub drain gasket". It is flat and made out of dense black rubber. I had to enlarge the center hole about 1/4" but that was easy to do using a utility knife.
Dimensions are 3" x 1 7/8" x 1/8". The visible outer circle is factory made, 1/8" thick and it compresses slightly. I tightened it up real snug and I can not make the lens rotate. It really looks like it is an original part of the lens(OEM). I think it's perfect, but time will tell. I'm going to do something similar to each lens I have, if nothing else just to stop the rotation.
Thanks to everyone, and I hope someone else will try this trick, I'm very happy with it.
Bill

E. von Hoegh
19-Nov-2012, 08:12
Cork is a classic gasket/spacer material and has proved itself over the years. As you say, there is cork... and there is gasket cork. There is also wine/champagne bottle cork too. :)

"Corkprene". Gasket cork is made of a mix of ground cork bits and neoprene. It's much sturdier than cork sheet, but it still won't keep the oil in the rocker covers of a smallblock Chevy if you overtighten the bolts. Or if the last guy overtightened the bolts.

AtlantaTerry
21-Aug-2015, 19:05
Here is an alternate solution for a gasket material. Instead of buying something from an auto supply or hardware store, go to your local bicycle repair shop. Ask them to give you a blown-out bicycle inner tube.

I wash and dry the inner tube to remove any lubricants, dirt, etc. Then when dry, I use it for all kinds of projects. I cut small sections out to make rubber rings to hold various things such as headphone or cell phone charger wires. I cut out flat sections to go between a tripod head and photo device - especially useful when the OEM cork has fallen apart. The inner tube section adds a large amount of friction preventing devices from rotating or twisting.

If you go to a truck repair center and ask them for a blown-out inner tube, then you can make larger projects with cut out sections. For example, a gasket to go between a lens and lens board.

The advantage of blown out inner tubes is they are free and unlike cork or the typical office rubber band, will not dry out and disintegrate. Plus, you can cut them to size.

RSalles
21-Aug-2015, 20:38
Terry,

Those tubes are a real helping hand, used some pieces to tight-light-seal the DIY btzs tubes i've made some days ago,

Cheers,

Renato

mdarnton
22-Aug-2015, 04:57
I cut washers from the dark plastic lids of coffee cans. Get a locking (mechanics) dividers with sharp points, and scribe the outside dimension first, gradually scribing through the plastic, then the inside hole. The material is soft enough to work cleanly with the scribers as cutter, but not so soft that it lets the lens sag, and I have a constant free supply. But the metal washers from the hardware are a new one for me! Usually I have this problem with #4 and #5 shutters, though.

Jim Andrada
23-Aug-2015, 20:16
I make spacers out of wood. I have a lathe and it's a quick turning job. Would look more "official" if I had a metal lathe though.

Jim Jones
24-Aug-2015, 05:33
With care, aluminum can be machined with woodworking tools. Hardware stores have it in various forms. Aluminum kitchenware is another source.