Jump to content

The Leica Forum uses cookies. Read the privacy statement for more info. To remove this message, please click the button to the right:    OK, understood.

Photo
- - - - -

35mm Summilux pre-ash focus tab - Redux


  • Please log in to reply
26 replies to this topic

#1 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 10 February 2017 - 08:35

Advertisement (Gone after free registration)

I love this little lens, but or such a brilliant lens, the thing that always got me (after the flaring hood problem was solved) was the dinky plastic focus tab. It's almost like the lens was made to a budget, which was exhausted before the focus tab was thought of. I have a few issues with the tab;

 
1) It's not really that deep, so I don't get a great feel from it. Unlike the more modern or older 'infinity lock' lens tabs which have are tighter radius and a deeper surface.
 
2) It breaks easily. When you see how it is secured, it's amazing any of them lasted so long. There is just not enough plastic to ensure it doesn't break. I think this limitation (having to secure it with a screw) influences the shape - it can't be deeper or either there isn't enough material for a strong(ish) attachment, or on the other hand it would protrude too far and hit a surface when you put the camera down.
 
3) Directly related to 2), Leica in their infinite wisdom will no longer sell the part to independent repairers. In fact, the only authorised repair service in Australia said that Leica won't sell the part to them and it would have to back to Germany to get replaced. At a minimum cost of 300 Euro. Plus shipping. Minimum!
 
You can see my initial post here
 
So given all of that, I thought I'd make my own. I wanted it to fit securely using the existing screw (not glue on like some replacements are - how inelegant is that!), requiring no modification to the lens. I also wanted to get the shape of the focus tab as close as possible to that of the 21mm Super Angulon which I believe has the best shape tab. It is also similar to the modern lenses and older ones like the 35mm Summaron for example. I also wanted it to have a weak point so it breaks rather than the lens.
 
I'm currently of prototype #2. Here is a shot of the first prototype and the original tab to compare the shape of the tab.
 
U55701I1486701531.SEQ.2.jpg
 
You can see the original (broken and glued back together) is relatively shallow, while my prototype v1 is deeper with a tighter curve. Mine is also metal (this one in Stainless Steel, v2 in Maraging Steel), so I need less material for the screw while maintaining strength, allowing it to maintain a low enough profile. v1 had a few issues though. Firstly the "wings" were a bit long and thin and it made manufacture too tricky so for v2 they were shortened and the depth increased. Secondly I was planning on tapping a thread for the screw, but it proved to be too secure and difficult. Basically there would not have been a weak point and the lens would have broken before the thread gave out.
 
Here is a shot of prototype #2
 
U55701I1486701530.SEQ.1.jpg
 
You can see I've made the changes to the "wings". What you can't see is that I've changed from tapping a thread on the inside to gluing a nut to the inside. The aim is that the glue here breaks before the lens does in the event of an accident, and then it can be simply glued back on. Nothing broken.
 
Changes for v3 (and hopefully final version). The 2 dowels and the nut need to be moved 0.5mm down (towards the rear of the lens). At the moment, it attaches a little bit too close to the front of the lens - you can almost see it overhanging. It doesn't get in the way, but is not elegant enough. It should and can be better. Apart from that, I'm super stoked with it (that means over the moon for non Aussies). It gives a way more positive feel, where I always felt like my finger was going to slip out of the original one. It's like a new lens.
 
Once I have the final design down, I'll make a batch (likely in Bronze) and offer them for sale in the buy and sell here. At the moment I'm piggybacking other jobs, so don't really get to choose the material... They'll cost about US$50, which is the same as some plastic ones that I've seen on the bay.
 
I think that the v4 summicron shares the same tab, so it *might* work on that lens too...
 
(This was also posted on RFF)

  • mnutzer, wattsy, mmx_2 and 4 others said thank you

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#2 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 11 May 2017 - 01:10

It's become pretty clear that I'm never going to get around to getting these made in bulk, and places like shape ways now do one offs super cheap (I'm getting one in brass for $22) so if anyone wants the SLT file, PM me and I'll email it to you for personal use only. You'll need an M1.6 nut and screw to attach it - the head of the screw need to be small, I filed one down until it fit. I might provide a little tutorial on how to attach it in time.

 

Cheers,

Michael


  • JMF said thank you to this

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#3 Abram

Abram

    Neuer Benutzer

  • Members
  • 171 posts
  • LocationOrange County, California

Posted 11 May 2017 - 20:51

There's a good chance I'll order one of yours as I had to have mine replaced but the replacement feels worse than the original AND it was $55 to add insult to injury. Gosh, I just really like that lens a lot though so it's worth figuring out a solution.


  • michaelwj said thank you to this

- Abram 

 

Design / Photography

www.abramgoglanian.com


#4 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 12 June 2017 - 13:07

For those who are interested, I've put the .STL files for two options of the tab on my google drive which can be accessed here and here. The first one (v8) is what I had made from raw brass through shapeways - see attached. It was pretty cheap, $22 I think. The second version (v9) is shaped to be more like the 2.8/35 Summaron style where the concave part is sloped. I haven't yet had one made, but the fixing is the same so it should work.

 

I'm passing on the files with the expectation that they will not be used commercially. 

 

U55701I1496581615.SEQ.0.jpg

 

It attaches by gluing a nut into the back (there is a space) and then just screwing it in from the inside. I also put a quick "how to" on RFF for those who are interested. It's a very easy job to do at home.

 

*It should fit the other lenses with the same type of plastic tab, but I'm not sure. If someone wants one for a different lens and can either get me a Leica tab or sufficient dimensions, then I can design one of them, or alternatively pass on my solidworks files as a starting point.

 

Enjoy.


Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#5 NB23

NB23

    Erfahrener Benutzer

  • Banned
  • 2,660 posts

Posted 12 June 2017 - 19:58

Michael,

I'd be careful. The next thing you know the chinese will have used your files and will be offering your creations all over ebay.

I'd be ok by ordering directly from you instead. I'd take 2.

Edited by NB23, 12 June 2017 - 20:00.

I love FOMAPAN 100.


#6 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 12 June 2017 - 22:57

Michael,

I'd be careful. The next thing you know the chinese will have used your files and will be offering your creations all over ebay.

I'd be ok by ordering directly from you instead. I'd take 2.


Good point. I'll look into offering it through shapeways today.

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#7 pico

pico

    Sponsoring Canine

  • Premium Member
  • 15,627 posts
  • LocationMinnesota
  • City / Ort:Winona

Posted 12 June 2017 - 23:01

There have been Chinese suppliers offering plastic tabs for Leica lenses for a few years. They require glue. Ugh! I put the one I ordered right in to the 'last resort' bin. If I needed one today, I would certainly try michaelwj.

 

Which prompts me to wonder why my 35mm Summilux (V2?) has a silver infinity locking tab. Ah, Leica variation, no?


Edited by pico, 12 June 2017 - 23:17.

  • michaelwj said thank you to this

do_not_touch.png


#8 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 13 June 2017 - 01:47

Hi All,

 

Following some advice here and on RFF, I've set up a shapeways shop that you can visit here. The focus tab in brass is US$35. If you want a different material then let me know and I'll see about adding it. It's in the classifieds too.

 

Here is my badly painted on installed after some heavy use over the last few weeks.

 

U55701I1497314822.SEQ.0.jpg

 

@pico, I agree, the glue is what prompted me into making my own. How disgusting! I have made this one so that it can be installed and removed without modifying the lens in any way, and also to have a weak point (the nut glued in) so that it doesn't damage the lens if the worst happens.


Edited by michaelwj, 13 June 2017 - 02:02.

  • pico said thank you to this

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#9 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 19 June 2017 - 01:36

I've just run through a few more designs at the request of various people, but this is one that I might print for myself next;

 

classifieds-31823-0-26711800-1497832138_

 

Modeled off the 2.8/35mm Summaron, but also quite similar to the modern integrated ones. 

 

It's pretty easy to get different designs happening (a little addictive really), and given a few measurements I can pretty easily make one for other lenses that took the plastic add-on tab. 


  • pico and Mute-on said thank you to this

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#10 pico

pico

    Sponsoring Canine

  • Premium Member
  • 15,627 posts
  • LocationMinnesota
  • City / Ort:Winona

Posted 19 June 2017 - 02:04

Michael, you are certainly a Maker.

So was my Mother. Good stuff.


  • michaelwj said thank you to this

do_not_touch.png


#11 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 19 June 2017 - 02:19

Michael, you are certainly a Maker.
So was my Mother. Good stuff.


Thanks pico, it's a good feeling creating something physical and useful!

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#12 wlaidlaw

wlaidlaw

    Erfahrener Benutzer

  • Premium Member
  • 13,170 posts
  • LocationLewes, UK and Tourtour, France
  • City / Ort:Tourtour, France and Sussex UK

Posted 19 June 2017 - 07:37

Michael, 

 

Does your additive printer do titanium? That might make the lightest and most robust tab. I have had a replacement camera part made for me in Titanium on a Renishaw 3D additive titanium substrate printer, on the recommendation of my son, who is a senior development engineer for Renishaw. Getting the drawings made and the STP file were far more expensive than the actual printing. I am hoping to sell some copies to Combat Graflex owners, to amortise my costs somewhat, as this is the part that often breaks, when someone fires off the clockwork motor drive without film in the camera. They are totally unobtainable and probably around 70-80% of all remaining Combat Graflexes are broken because of this. The original part is a fragile machined aluminium diecasting. It is a ring with two simple lugs on the top but two quite complex lugs on the underside. The broken ring is arrowed. It was broken into three pieces and one double sided lug had broken off completely as you can see.

 

Wilson

Attached Files


Edited by wlaidlaw, 19 June 2017 - 07:40.

  • Exodies said thank you to this

#13 Exodies

Exodies

    Picturer

  • Premium Member
  • 3,469 posts
  • LocationLuxembourg

Posted 19 June 2017 - 08:04

Such a clean machine. Bravo.

#14 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 19 June 2017 - 08:05

Hi Wilson,

 

These were done through shapeways, no Ti unfortunately. Stainless, Aluminium, Bronze are all okay. At some level I don't want it to be too strong, if anything is going to break I'd prefer it was the tab over the lens :) . There is another local printer that can do Ti, I haven't had the best experience with them. In the end brass is easy, wears nicely, and the weight is not much - it is more or less hollow. Although if I had a Ti Summilux, I'd get one made from Ti.

 

It has indeed revolutionised small run, small parts manufacturing. I can't imagine what it would have cost to get the parts we made with a CNC machine, but I'd bet it would be at least 10x as expensive.

 

I'm fortunate in that I use SolidWorks regularly through work so designing these was part of learning to do some new things. I spent about 3 hours getting the base part correct, but once that's sorted, modifications are easy. For example, going from the 1st version to the one in post #9 above took about 20 minutes. I think that part of the cost of the design is translating what is required to the designer, and of course the program is very expensive.


  • wlaidlaw said thank you to this

Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#15 wlaidlaw

wlaidlaw

    Erfahrener Benutzer

  • Premium Member
  • 13,170 posts
  • LocationLewes, UK and Tourtour, France
  • City / Ort:Tourtour, France and Sussex UK

Posted 19 June 2017 - 10:29

Michael, 

 

It would have been much cheaper if I could have got my son to do the scans of the broken part, make the drawings and then the STP file. However he is so stacked out with work, developing the next generation of Renishaw Ti 3D printer, which the board wants all completed, tested and ready for production by yesterday, he could not even consider it. I therefore used a automobile development company I knew, called Frazer-Nash. It helped that I used to race one of their historic Le Mans Replica, Bristol engined cars, which they had built in 1951. With a bit of luck I should get my totally rebuilt Combat Graflex back in the next few weeks. I would guess it will be one of the very few fully operational ones of these in existence. I have been building up my stocks of 70mm film in anticipation. 

 

 

I wanted to put a focus tab on my 1999 Special Edition LTM Series V 50mm Summicron. At the moment I am using one of the TAAB synthetic rubber ring type tabs. It is not very elegant but it works and at $10, it does not break the bank. 

 

Wilson

Attached Files

  • Attached File  TAAB.jpg   435.11KB   2 downloads

  • michaelwj said thank you to this

#16 Mute-on

Mute-on

    Erfahrener Benutzer

  • Members
  • 436 posts

Posted 19 June 2017 - 10:57

I've just run through a few more designs at the request of various people, but this is one that I might print for myself next;
 
classifieds-31823-0-26711800-1497832138_
 
Modeled off the 2.8/35mm Summaron, but also quite similar to the modern integrated ones. 
 
It's pretty easy to get different designs happening (a little addictive really), and given a few measurements I can pretty easily make one for other lenses that took the plastic add-on tab.


I'm really liking this design, Michael. It looks properly finished now. The grooves are very practical in use, too.

Cheers,

J :)
  • michaelwj said thank you to this

#17 wlaidlaw

wlaidlaw

    Erfahrener Benutzer

  • Premium Member
  • 13,170 posts
  • LocationLewes, UK and Tourtour, France
  • City / Ort:Tourtour, France and Sussex UK

Posted 19 June 2017 - 11:05

Such a clean machine. Bravo.

 

Alan Starkie of Cameraworks-uk, has had it completely in pieces for a total rebuild. I am nervously anticipating a large bill from him, although I have already paid for the 3D printed parts separately. Alan also did the rebuild and repaint of the Model III, you can see in the photo above. He really does lovely work. 

 

Wilson


  • michaelwj said thank you to this

#18 michaelwj

michaelwj

    Erfahrener Benutzer

  • Members
  • 1,343 posts
  • LocationBrisbane

Posted 19 June 2017 - 11:36

I'm really liking this design, Michael. It looks properly finished now. The grooves are very practical in use, too.

Cheers,

J :)

 

 

It's not too different from the Summaron one, except the Summaron is wider at the base and the front tapers towards the top. At the top it is very similar.

 

I'm wondering how the grooves will paint...


Cheers,

Michael

 

Get my replacement brass 35mm Summilux focus tab


#19 wlaidlaw

wlaidlaw

    Erfahrener Benutzer

  • Premium Member
  • 13,170 posts
  • LocationLewes, UK and Tourtour, France
  • City / Ort:Tourtour, France and Sussex UK

Posted 19 June 2017 - 13:07

It's not too different from the Summaron one, except the Summaron is wider at the base and the front tapers towards the top. At the top it is very similar.

 

I'm wondering how the grooves will paint...

 

 

My 35/2.8 Summaron is a bit different but it is an LTM one with an infinity lock at the camera side of the tab.

 

I have sprayed things like lens hoods when I could not  get them in the correct colour. I used an air-brush with Vallejo paints, spraying thinners and drying retarder. If you experiment a bit, you soon get the hang of laying down very thin coats, which due to the drying retarder, meld into each other to give a very professional looking smooth finish. I found Vallejo much better than the usual Humbrol or Revel paints. You can clean the gun with regular acetone or commercial cellulose paint thinners, which are a fraction of the price of air brush cleaning solvent. 

 

Wilson


  • michaelwj said thank you to this

#20 luigi bertolotti

luigi bertolotti

    Erfahrener Benutzer

  • Members
  • 11,822 posts
  • City / Ort:Brescia

Posted 15 July 2017 - 11:35

In praise of Michaelwj work, here is, just arrived, my replacement tab for my Elmarit 28 v3 (the original went broken and partially lost in action...) : a fine and perfectly fitting item : the brass looking is so fine that I'm uncertain if is worth to embark in black painting it before attaching it definitely... (I suspect I'd end up with a black not perfectly consistent with lens, and maybe at risk of paint wear in usage)

Attached File  Elmarit_28_newtab1.jpg   119.97KB   4 downloads

Attached File  Elmarit_28_newtab2.jpg   144.53KB   3 downloads
  • paulmac and michaelwj said thank you to this


0 user(s) are reading this topic