Graflex.org Forum Index Graflex.org
Get help with your Graflex questions here
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Lensboard drawing for R.B. Tele Graflex required

 
Post new topic   Reply to topic    Graflex.org Forum Index -> Reflex Help
View previous topic :: View next topic  
Author Message
markusschmidt



Joined: 25 May 2007
Posts: 4
Location: Betzdorf-Germany

PostPosted: Sun May 27, 2007 10:40 pm    Post subject: Lensboard drawing for R.B. Tele Graflex required Reply with quote

Hi from Newbie to the group,

I am from Germany, just an hour east of Cologne in a hilly region. 57 years old, married, two grown up children. Taking fotos since I was 10 years (started with a Agfa Click 6 x 6 cm Rollfilm camera). After many years of taking fotos in 35mm only, I started to collect old cameras and to take fotos with them as well. Many of them are rollfilm cameras, and using modern film, they give excellent results. So I went into MF some 8 years ago and bought a used Mamiya 645/1000s which I use until now, together with my Canon EOS D60 and EOS 50, not to talk about my collection. So I always have one or two of the old cameras with me, depending on weight and opportunity

I just have acquired an early R.B. Tele Graflex w. revolving back 4"x5" from the US via pebay, it´s got Ser.No. 94576 and a neat Carl Zeiss f4,5/165 lens. It´s my first large format reflex camera. I want o to get the RB working well again, just for fun. It came with an adapted (?) Rokuohsha rollfilm back for 6 x 9cm that seems to fit well. Later I will have to check wether focussing on ground glass and on rollfilm back are matching.

Today I´ve been cleaning the RB and checking what I will have to do for restoration.

Bert Saunders kindly gave me many very explicit hints for the shutter checking and restoration, his fast and friendly response was quite motivating for me to get the RB to work well again. He seems to be the good genius of this group among many other helpful persons here.

So I startred checking.

The RB is working, shutter as well, just tension is too low and cloth a bit stiff but not too much.

Camera has some wear on the housing (not a problem, leather still there), a small hole in the bellows (can be glued from inside), some ten tiny pinholes in the curtain, some loose wood screws but I think overall not too much trouble for a ninety year old wooden camera. Hood, mirror and ground glass are perfect (or were exchanged long ago), just had to clean them up carefully. As ground glass is marked from below, I just cleaned it with alcohol from top and carefully with a soft brush from underneath.

I will have to build a new lensboard as well, as the old one (made of plywood, not sure if this is the original material) is coming apart. Lens is quite heavy. So I thought to use wether aluminium or POM or PA6 plastic (sacrilege, if I don´t find a piece of nice hardwood) for this. Actual size is 84 x 84 mm = 3-5/8" and 5,5 mm = 7/32" thick. I can take the dimensions and shape from this one, but would prefer to have a tech drawing of the original one. Anyone out there can help ?

This RB Tele also has a kind of additional attachment device on front, don´t know what for, looks similar to the normal lensboard attachment device working similar as the back installation device. Someone knows what is was intended for ? Cannot be for a lens as it would collide with the front flip-up door ...

Enough questions ...

Thanks and greetings from Germany

Markus
Back to top
View user's profile Send private message Send e-mail
45PSS



Joined: 28 Sep 2001
Posts: 4081
Location: Mid Peninsula, Ca.

PostPosted: Wed May 30, 2007 11:45 am    Post subject: Reply with quote

Quote:
I will have to build a new lensboard as well, as the old one (made of plywood, not sure if this is the original material) is coming apart. Lens is quite heavy. So I thought to use wether aluminium or POM or PA6 plastic (sacrilege, if I don´t find a piece of nice hardwood) for this. Actual size is 84 x 84 mm = 3-5/8" and 5,5 mm = 7/32" thick. I can take the dimensions and shape from this one, but would prefer to have a tech drawing of the original one. Anyone out there can help ?


This is going to get interesting:
According to A history of Graflex by Paine the Telescopic Revolving Back Auto Graflex 1912-1914 , a 4 x 5, has a 4x4 lens board. The Telescopic (Tele) Revolving Back Graflex 1915-1923 in 4x5 should have a 4x4 lens board but it is noted that 1918 had a 3 3/4 x 3 3/4 lens board.
I have a Series B Graflex that when I requested a date for it, it turned up it was at the top of a block of numbers assigned to the Tele Graflex starting production in early 1922. (The Series B changed design and is offically listed as starting in 1923. There are Tele's with serial numbers in 1926, 3 years after it was discontinued.) Did Graflex make different front standards or at least change the lens board opening in the front standard from year to year?
The 4x5 Series B (dba Tele Graflex rebaged) that I have has a lens board stamped B on the back and measures as follows:
Top to Bottom=3.741 inches/95.12mm
Left to Right=3.729 inches/94.72mm
Thickness= .25 inches/6.37mm
Front=flat
Rear: Edges Rabeted as follows:
Left and right: inward from outisde edge= .141 inches/3.58mm
Bottom: inward form outer edge=.254 inches/6.45mm
Top: inward from outer edge=.254 inches/6.45mm; approximate 45 degree bevel rear to front of board that leaves the top edge .092 inches/2.34mm thick and goes .118 inches/3mm inward from top edge (roughly 1/2 of the width of the rabet).
Rabet depth=.112 inches/2.85mm.

You can measure your camera's lens board opening left to right/top to bottom to get the basic measurement. Next measure the depth of the slot at the bottom and add that to the top to bottom measurement. Now measure the top edge to tension spring when it is in the uncompressed state and add that to the top to bottom measurement. The alternative will be to measure from the base of the lens board slot at the bottom to the edge of the spring uncompressed for the top to bottom measurement.
Measure the top to bottom and left to right of the front standard immediately behind the lens board slot. This will be the size of the back of the lens board once it is rabeted. The rabet forms the light trap. Bevel the top edge so that the board will go in at a 45 degree angle and rotate inward into position to slide into the slot. If you make it a little large it can be sanded/filed down to fit but if a little small it cannot be enlarged.
Material suggestions are Baltic birch plywood, Mahogany, black ABS Plastic, and black Acrylic work well for lens boards. Any material that will not warp, at least 1/4 inch thick and is rigid can be used.
Charles
Back to top
View user's profile Send private message Visit poster's website
markusschmidt



Joined: 25 May 2007
Posts: 4
Location: Betzdorf-Germany

PostPosted: Sun Jun 10, 2007 4:32 pm    Post subject: Reply with quote

45PSS wrote:
Quote:
I will have to build a new lensboard as well, as the old one (made of plywood, not sure if this is the original material) is coming apart. Lens is quite heavy. So I thought to use wether aluminium or POM or PA6 plastic (sacrilege, if I don´t find a piece of nice hardwood) for this. Actual size is 84 x 84 mm = 3-5/8" and 5,5 mm = 7/32" thick. I can take the dimensions and shape from this one, but would prefer to have a tech drawing of the original one. Anyone out there can help ?


This is going to get interesting:
According to A history of Graflex by Paine the Telescopic Revolving Back Auto Graflex 1912-1914 , a 4 x 5, has a 4x4 lens board. The Telescopic (Tele) Revolving Back Graflex 1915-1923 in 4x5 should have a 4x4 lens board but it is noted that 1918 had a 3 3/4 x 3 3/4 lens board.
I have a Series B Graflex that when I requested a date for it, it turned up it was at the top of a block of numbers assigned to the Tele Graflex starting production in early 1922. (The Series B changed design and is offically listed as starting in 1923. There are Tele's with serial numbers in 1926, 3 years after it was discontinued.) Did Graflex make different front standards or at least change the lens board opening in the front standard from year to year?
The 4x5 Series B (dba Tele Graflex rebaged) that I have has a lens board stamped B on the back and measures as follows:
Top to Bottom=3.741 inches/95.12mm
Left to Right=3.729 inches/94.72mm
Thickness= .25 inches/6.37mm
Front=flat
Rear: Edges Rabeted as follows:
Left and right: inward from outisde edge= .141 inches/3.58mm
Bottom: inward form outer edge=.254 inches/6.45mm
Top: inward from outer edge=.254 inches/6.45mm; approximate 45 degree bevel rear to front of board that leaves the top edge .092 inches/2.34mm thick and goes .118 inches/3mm inward from top edge (roughly 1/2 of the width of the rabet).
Rabet depth=.112 inches/2.85mm.
....Charles


Charles,

in the meantime I closed some tiny pibholes in the curtain and checked and cleaned all mechanical parts well, adjusted shutter spring force etc., so now it is working well. Next will be cosmetical work on leather etc.

The lensboard made of wood that came with the camera, is between 3 and 6 mm thick and corresponds to your description, except size which is merely 84 by 84 mm. Could it be that the fron part was changed by someone to receive a lensboard from the 3 1/4 by 4 1/4" or 3" by 4" type RB ?

To be sure that it is a 4x5 RB Tele (except the badge indicating "RB Tele Graflex") I measured the revolving back as well :
It can take up film holders with a size of up to 133 mm by 107 mm which is about 5 1/4" by 4 1/4", opening in it for giving light to film is 105 mm by 80 mm or 4 1/8" by 3 1/8"

Lens support extends max. about 65 mm frontwards out of housing. From that point, lensboard is positioned 28,7 mm or 1 1/8" rearwards (front plane of lensboard. On front of the lens support, although there is the snap open front cover, I found a fixing device like for a very thin lensboard (just about 1 mm), size might be 124 mm high and up to same width. I believe that this is a support for a flexible shade bellow or something similar ?

I also noticed that all all lateral support plates are not moulded but just flat nickel plated metal, between 1/16" (upper shutter and mirror control) and 1/32" thick (lower plate for shutter tension control).

Regards,

Markus [/img]
Back to top
View user's profile Send private message Send e-mail
45PSS



Joined: 28 Sep 2001
Posts: 4081
Location: Mid Peninsula, Ca.

PostPosted: Sun Jun 10, 2007 10:55 pm    Post subject: Reply with quote

Quote:
To be sure that it is a 4x5 RB Tele (except the badge indicating "RB Tele Graflex") I measured the revolving back as well :
It can take up film holders with a size of up to 133 mm by 107 mm which is about 5 1/4" by 4 1/4", opening in it for giving light to film is 105 mm by 80 mm or 4 1/8" by 3 1/8"

Markus,
What you have is a 3 1/4 x 4 1/4 camera. The camera size is determined by the film size, or film opening. The camera will take Graflex film holders or bag magazines only.
A 4x5 Graflex film holder measures 5 inches x 6 3/4 inches (127mm X 171.5mm) on the outside at the back mounting and has a film opening of 3 3/4 inches X 4 3/4 inches or 95.25mm X 120.65mm (1 inch=25.4mm).
Charles
_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.
Back to top
View user's profile Send private message Visit poster's website
markusschmidt



Joined: 25 May 2007
Posts: 4
Location: Betzdorf-Germany

PostPosted: Mon Jun 11, 2007 8:22 pm    Post subject: Reply with quote

Markus,
What you have is a 3 1/4 x 4 1/4 camera. The camera size is determined by the film size, or film opening. The camera will take Graflex film holders or bag magazines only.
A 4x5 Graflex film holder measures 5 inches x 6 3/4 inches (127mm X 171.5mm) on the outside at the back mounting and has a film opening of 3 3/4 inches X 4 3/4 inches or 95.25mm X 120.65mm (1 inch=25.4mm).
Charles[/quote]

Charles,

thank you, now I know at least where I am with it ... I didn´t know that the RB Tele was built as well for this film size. That explains the smaller lens board as well. Only thing (except cosmetics) which I have to do technically yet, is to make the ground glass focusing through the waist level finder synchronize with the adapted rollfilm back that came with the camera.

Thanks again for your kind information and help.

Regards, Markus
Back to top
View user's profile Send private message Send e-mail
45PSS



Joined: 28 Sep 2001
Posts: 4081
Location: Mid Peninsula, Ca.

PostPosted: Mon Jun 11, 2007 9:39 pm    Post subject: Reply with quote

I assume that you have a standard roll film holder, correct? The Graflex film holders and roll film holders have the film plane 1mm (+0mm/-.1mm) futher back than the standard film holders and roll film holders. It should be easy to attach a .999mm shim to the face of the roll holder so that it sits in the correct position when attached to the camera.
Charles
_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    Graflex.org Forum Index -> Reflex Help All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group