Kategorie: Tools

On the agfa isoletta I already had to repair an compur shutter, following this very good article :

http://www.rolandandcaroline.co.uk/repair.html


Now I got my new 150mm Schneider objective 4×5 for the -soon to come- intrepid camera.

+  I got it cheap
–   The compur synchro shutter was stuck

So first I needed some info´s :

 http://benoit.suaudeau.perso.neuf.fr/manuels_rep/obturateurs/Compur-shutter-repair-manual.html


http://www.skgrimes.com/library/used-obsolete-discontinued-shutters/compur/operation-of-compur-1-shutters

https://www.youtube.com/watch?v=N5SZbGuNHmE

and of course :

http://rick_oleson.tripod.com/index-55.html


Than I took the linhof technika board of, easy. It got cleaned and some repaint.

Next was the front element fo the lens, using my trusted part of rubber tire it came of, the tubus also.
The back element followed.
Both lenses I cleaned with compressed air, a few spots I had to wipe careful with isopropanol or benzin (naphta).

The shutter did work after bathing in isopropanol and lots of dirt came of, but twice after drying – stuck.

So of came three very small screws, the front plate of, turning the „half screw of compur“ and away with the holding plate/ring.
Now you could pry of the time ring, but careful – no more firing the shutter now !

Cleaning all the parts so far removed, visual insprection, naphta bath. Than I put some acid free oil (I prefer Ballistol) with a q-tip on the sensible small mechanics, a few minutes later – a perfect working compur shutter.

I put it together again – and have a splendid working 150 mm 4×5 lens.

So far my new intrepid camera did not arrive, but I got another compur synchro with a nice 210mm lens.
I hate guys who put the screws seemingly with powerwrenches on the fine treads, but with drops of oil, waiting,waiting longer, using a wrench with rubber protectors and an lens wrench I got the lens board plate screw of.

Than my usual taking of the lenses, they are put away for a careful cleaning if needed. Some paint flakes went away with the air blower, small specks at the front element went of with isopropanol. A small cratch is remaining.

Disassembly of the compur, bathing the components in Isopropanol, I even put the very dirty mechanism in an ultrasound cleaning bath, than applying small amounts of an lubricant seems to have got the shutter working very well.

My 8×10 groundglas broke.

Searching ebay, the prices were way too high.

But I found :

https://borutpeterlin.wordpress.com/2013/09/16/how-to-make-a-ground-glass-for-view-camera/

So I bought siliziumkarbid, fine grain (lifelong lasting 1000g) 600 and 800,

the local glass shop cut me a 2mm glassplate the right size, tested it in camera

and went to work for about 40 minutes.

I used a second smaller glass plate, put a sucking grip on it.

Than I put the 600 powder on the new ground glass, added some water and began to grind. Hard work for my hands . About 10 min later I switched to the 800 powder, water of course and another 15 mins later I had my glass ready.

The result : a good groundglass, but not so bright as I hoped.

A few tips I got as feed back:

The general rule is that a coarse-ground screen will be brighter, but a finely ground one will be easier to focus.

Use WD40 instead of water, its going much more easy.

Use aluminium oxide powder.

Add a fresnell screen.

Broken and grounding – comparison

For working I put an vacuum holder (from and old car something device) on a 9×12 glass plate I would have used for ambrotype. A spoonful siliziumkarbide and a few drops water, and a few drops sweat…

20 minutes later the new groundglass in my international 8×10 back :

Here is an overwiev of lensboard parameters as far as I got the infos :
Please correct and submit infos !


Sinar

Sinar boards are quite complex. They are 139 mm square, outer rim is 4 mm thick (front to back) and 2 mm wide, recess is then 1 mm down from that, center area is 5 mm thick, recess is 3.5 mm wide. #1 hole is 35 mm, #3 is 60 mm.

140×140 mm, 3,5 mm thickness, a lighttrap on the inside


Mentor

138x142mm bei 7 mm thickness (similar to the Stella von Herbst and Firl Görlitz)


Plaubel Peco Profia

166x166mm with rounded edges, the newer onees need a lighttrap on the inside

Plaubel Profia Z 13×18/5×7 : Adapterplatte auf die Technikaplatten, die gibts fertig bei Plaubel. Es gibt auch noch baugleiche 96×99 Platten von Toyo

Linhof

74×81 mm : Baby Linhof Technika 6×9

96×99 mm, thickness 1.7mm : Linhof Technika 9×12 and Linhof Color & Kardan Color 9×12 ( plus Toyo, Wista, Tachihara, Shen-Hao, usw..).

129×129 mm : Linhof Technika 13×18

162×162 mm : Linhof Kardan, Kardan Super-Color

220 x220 mm : Linhof Kardan 13×18 u. 18×24

ca 200 x 200 mm : Linhof Kardan Color 13×18 u. 18×24

162×162 mm : Linhof Kardan from 1967 (Kardan Bi and later)



Arca Swiss

6×9, „Field“-4×5 and Misura : 110×110 mm

9×12 – 4×5″, 13×18-5×7″, 18×24 – 8×10″ „new“ 141×141 mm

9×12 – 4×5″, 13×18-5×7″, 18×24 – 8×10″ „old“ Oschwald (vor 1984), F-line 4×5 (1984 to ~2005) and Discovery : 171×171 mm


TOYO 4×5 C

158x158mm, 5mm thickness



Cambo SF,SC

162x162mm, rounded edges, lighttrap, 3,5 mm thick, 2,5 mm thick at the lens bore

Graflex

Outer dimension of 3.64 x 3.7 inches (92.5 x 94mm),


Compur und Copal have the same dimensions 0, 1 and 3

0 = 34,5mm
1 = 41,5mm
3 = 65,0mm

The Compur 2 has 3 different possibilities.

The pneumatic Compound shutters:

Compound III: 62mm
Compound IV: 92mm
Compound V: 95mm

A very good reference :

Intro