Betax #4--hard to repair?

Tom1956 · Aug 1, 2013

I finally won an auction for a 12 inch lens for my 8x10. Had to do it the poor-man's way, like everything in my life. It's a Bausch and Lomb in a Betax #4. The ad said the shutter "used to work, but doesn't now". So it looks like I'm going to have to do either the naptha trick or the alcohol trick, depending on what the shutter blades are made of. And if that doesn't work, I'll have to open it up. I never worked on one of these. Rather than asking for detailed advice, should I expect things to go flying through the air upon opening it? Where is the access point to the interior of the shutter? I might mention that it looks like there's no retaining ring. So that means I'll have to carefully file my homemade wooden lensboard (which doesn't exist yet), so the shutter is jammed in the hole and put a bead of hot glue around the threads. Not having a retaining ring is disappointing, but not earth-shattering. Thanks.

Andrew K · Aug 1, 2013

From memory (and it's been a while....) they are easy to fix. Being so large there is lots of space to work, and from memory (well either the #4 or #5) has the shutter blades screwed in to the backing plate, so when oyu dismantle it things don't fall out when you least expect it....

I found these pics on the web - they should help you...

http://www.flickr.com/photos/tomshue/sets/72157627413633924/detail/

have fun!

Andrew

Tom1956 · Aug 4, 2013

Now here's something really crazy. I just went way down deep into this shutter. To the point that shutter leaves are coming off their pins and fell out. I've got a picture of how they go, so that much I'm happy enough about. But I've got a leaf leftover. There are 5 pins, and the picture of the shutter I'm looking at on the web has 5 leaves. So why do I now have a 6th one leffover? BTW. Somebody has been into this thing before. The original problem was that the mechanism and timer worked OK but the shutter wasn't opening. Where in the world did this 6th shutter leaf come from? There's no place to put it back in. All the pins are taken. Strange.

Jon Shiu · Aug 5, 2013

I don't know about that model of shutter, but I would try putting it on top of the first leaf put in. In other words, say you are putting the leafs on in a clockwise manner. After putting the 5th one in, put the 6th on top of the first one you put in. Hope this helps.

Jon

Tom1956 · Aug 5, 2013

That's what I thought too, and it seems to work. I'm beginning to think this whole shutter needs a good powdering of graphite the way it's designed.

Andrew K · Aug 5, 2013

also check if there is a slight bend to any of the tips (the pointy ends) of the shutter blades - if there are the first one you pt on should point down, and the last one point up.

otherwise yes - the 6th is a capping blade and goes above where the first one went

Tom1956 · Aug 5, 2013

The blades seem to be made out of plastic. I thought about that too, but I'm not sure plastic can keep any kind of meaningful bend. Plastic in 1912, I doubt it, but they sure don't seem to be metal. I,ve got that much of it back together, but I'll take it back apart tomorrow because it looks like 2 blades could be shifted to make the stack a little tighter.. As I hold it up to the light I can see a little light leaking around when I turn the assembly to a sharp angle to the light bulb. I only originally had 3 of the six blades fall out and get mixed up. I suppouse I was bound to disassemble the shutter more than I really needed to, but sometimes you have to do that before you understand.

Tom1956 · Aug 5, 2013

Another thing. I looks like the actual timing mechanism does not have any viable way to correct the timing. Looks like a simplified Nikon F self-timer mechanism. Just no adjustment. Looks like the only real way to know what shutter speeds are is to buy a cheapo EBAY shutter-speed tester, and mark the dial according to that. I'm also amazed this shutter has no setting for 1 second. They give you 2, 5, 10, 25, 50 T and B, and that's it.

Tom1956 · Aug 6, 2013

Well, lets continue on for the edification of future internet searchers. I've disassembled this shutter completely. I had to--the aperture blades had slipped out of their sockets after the solvent treatment. I discovered a past worker had likewise disassembled the aperture pivot plate and had bent a couple of the aperture blades slightly. I had the dickens of a time putting the upper pivot-slot plate back in proper position such that the aperture assembly could move full travel. After finishing, it has a tendency to jam and want to cause the blade pivots to slip under and past their slots.
Oiling does help, but not a lot--the blade pivots still want to slip underneath the slot-plate and jam the mechanism. And this is where I have reached a conclusion regarding lubrication. Lubrication MUST be used on this mechanism, but I think it should be graphite, not oil. I believe graphite should be allowed to migrate on the aperture blade surfaces, further reducing the binding problem which causes the aperture-blade pivots to slip underneath and past their slots, causing jamming, bending, and probable breakage of aperture blades. I'm going to soak it in naptha to remove any oil I applied tonight and go buy some graphite tomorrow. The design of this shutter inherently causes oil to migrate out onto the aperture blade surfaces. This is bad. If graphite migrates, it seems that would actually be for the better.

shutterfinger · Aug 6, 2013

All you need for shutter CLA:
extra fine powdered graphite http://www.agscompany.com/lubricants/homehardware/183
light weight oil http://www.triflowlubricants.com/Tri-Flow_Superior_Drip_Lubricant.html
white lithium grease http://www.amazon.com/Permatex-80345-White-Lithium-Grease/dp/B000HBNV58
degreaser that leaves no residue and is safe to use on rubber and plastics http://www.amazon.com/CRC-Electrical-Contact-Cleaner-Aerosol/dp/B003NTQCA2

3in1 oil is vegetable base and will dry out quickly and leave a sticky residue.
Water Disperant 40 contains a light weight vegetable based oil and leaves a sticky residue.
Lighter fluid leaves an oily residue.
Naphtha will damage plastic and rubber components used in shutters made form the 1940's and newer.

I rub the graphite into the aperture and shutter blades and their pivot pins with a q tip then remove any cotton fibers.

The #1 shutter blade has a special pin for the #6 capping blade, it will be different from the other blades.

Shutter speed testing, the last posts are the most up to date. I put a piece of dark red lighting gel equivalent to a #25 red filter over the sensor and use a 2 AA cell mini mag set to spot at 2 inches for tests.

Shutter blade starting point is adjacent to the release lever and goes clockwise as viewed from the front of the shutter. The photo below is inaccurate, I am unable to delete it. The correct on is above.

Tom1956 · Aug 6, 2013

Thank you. But for this purpose, I am going to go with graphite, as graphite migration out onto the aperture blades could actually logically be beneficial. The way the assembly is made, the ends of the blades are jut stamped indentations that are trapped in their slots in the aperture plate. Now, the stampings have gotten sloppy and allow the blades to slip under their slots and out of place, jamming the stack and bow outward causing more damage. CRC won't work on this as I've tried a similar aerosol manufacture by my big customer locally. Lithium grease--no. Oil--not very good. I think this calls for graphite.

shutterfinger · Aug 6, 2013

Graphite- shutter and aperture blades, NO OIL or GREASE!
Oil- trace on pivots and shafts for gears and levers only.
Grease- spring ends especially where they slide on other surfaces; levers where they slide against other surfaces. A dab about the size of a straight pin head or less is all that is needed. Trace on gear teeth.
The CRC is excellent the other manufacturers stuff may be garbage.

"the ends of the blades are jut stamped indentations that are trapped in their slots in the aperture plate"
Insert an ice pick or similar instrument into the center of the blade end and spread the stampings. The edges of the stamped protrusion can break off, extreme care must be taken.
Want to rent my sledge hammer if all else fails?

Tom1956 · Aug 6, 2013

Hey, I'm telling you what--that graphite's the stuff. Go ahead and slather it on there, work it in, and what's not needed will just dump out. Yessireebob. Now we're cooking.

shutterfinger · Aug 6, 2013

Once you get the shutter back together and working set it to its fastest speed and set and trip it 10 to 20 times with no lens elements attached to dislodge any loose graphite that did not shake off.

Tom1956 · Aug 7, 2013

Well I've got this thing back together. I might add that is was no small feat. At first the shutter would not trip. Some BOOB had been tinkering with it and had bent the long trip arm that extends from 11 o clock to 4 o clock on the right side, and it was not catching the little trip dealie at about 3:30 o clock.As it turns out that long arm is VERY important to be bent just so, as it has a lot to do with accuracy.
Now that the whole thing is nice and clean and wrokd like a new one, I have a question because I have no shutter checker. There are only 5 speeds on this thing--50, 25, 10, 5, 2. But I can barely tell any difference between 1/10 and 1/25. Or is this normal for us human beings? I wish I could get my hands on the technique for tuning shutter accuracy. It seems it would have lot to so with spring bending or lever bending, or both to fine-tune this shutter.

shutterfinger · Aug 7, 2013

Well, in editing my first post and attempting to get rid of the incorrect photo the link to the simple shutter speed tester got deleted so here it is:
http://www.graflex.org/helpboard/viewtopic.php?t=6105
read through the entire post first as the latter posts are the most up to date.

When checking a shutter by eye position the shutter so that you can see the shutter blades and the second hand of a watch or clock. A clock with a sweep hand is best.
Set the shutter to the 1 second setting, set the shutter, trip just as the second hand is in line with a second mark. The shutter should open and close just as the second hand gets to the next second mark.
Set the shutter to the 1/2 second setting and repeat. The shutter should open and close just as the second hand reaches the mid point before the next second mark.
Set the shutter to the next higher speeds in sequence and verify that the speed increases until you get to the 1/50~1/60 then set to the next slowest speed and verify it is longer than the previous.

Normally if the 1 and 1/2 second speeds are correct the rest will be reasonably correct up to 1/100 second. Speeds faster than 1/100 use a booster spring and the condition of that spring and wear on the shutter determine if the fast speeds are good.

Tom1956 · Aug 8, 2013

A little problem

shutterfinger said:
Well, in editing my first post and attempting to get rid of the incorrect photo the link to the simple shutter speed tester got deleted so here it is:
http://www.graflex.org/helpboard/viewtopic.php?t=6105
read through the entire post first as the latter posts are the most up to date.

When checking a shutter by eye position the shutter so that you can see the shutter blades and the second hand of a watch or clock. A clock with a sweep hand is best.
Set the shutter to the 1 second setting, set the shutter, trip just as the second hand is in line with a second mark. The shutter should open and close just as the second hand gets to the next second mark.
Set the shutter to the 1/2 second setting and repeat. The shutter should open and close just as the second hand reaches the mid point before the next second mark.
Set the shutter to the next higher speeds in sequence and verify that the speed increases until you get to the 1/50~1/60 then set to the next slowest speed and verify it is longer than the previous.

Normally if the 1 and 1/2 second speeds are correct the rest will be reasonably correct up to 1/100 second. Speeds faster than 1/100 use a booster spring and the condition of that spring and wear on the shutter determine if the fast speeds are good.

I'm sort of hoping von Hoegh will click on and chime in on a little situation I'm having to deal with. Lacking illustrations, this question can be described adequately verbally. Specifically I'm inquiring about a proper glue for a purpose. What I have here is the shutter-close spring has gotten weak over the years. Lacking any small gauge spring-steel stock I'm forced to go with the original spring. Because of this I cannot tighten down the 5 shutter hinge screws that hold down the top shutter plate. I have to leave the screws a bit on the loose side to keep from squeezing the shutter blades between the top and bottom plate. No real matter, but I think I ought to paint on some sort of glue to keep the 5 shutter blade screws from backing out any more than they are. But what kind of glue can you paint on these screws and the surrounding flat surface to keep the screws in place? Of course, the best remedy is to obtain some proper spring-steel stock and make a new spring, which wouldn't be all that difficult. Then I could snug up the shutter-hinge screws and end the matter. Thanks.

shutterfinger · Aug 8, 2013

It is possible the shutter pivot posts have been compressed from overtighting the screws in the past or the shutter blade retaining plate has become deformed resulting in the plate putting too much pressure on the shutter blades.

as for holding the screws in place Locktite 242 threadlocker will work or any non expanding glue that will stick to metal should work.

Tom1956 · Aug 10, 2013

Somebody Tell Me What I've Got Here.

http://www.ebay.com/itm/Bausch-lomb...HlNRfV4ZXBPkBpMftRXN8%3D&orig_cvip=true&rt=nc

The above EBAY listing now over on about 8-3-13 was the lens I've bought. That's what this whole thread is about--following me through a first time Betax procedure. Never again to be a self-proclaimed expert of naptha-dipping boobs. Each repair that isn't like the repetitious ones of the past; is refreshing. This one was an discovery adventure to un-doing the effects of age and part-bending tinkerers to get it to work. What they were fighting was a worn-out shutter-return spring, and their own inability to unscrew a screw without chewing it up. In 101 years since the engraved 1912 dating, I figure about 5 different guys had been into this. I do thank god they managed to pass on perfect glass without so much as a cleaning mark. And now the shutter is back to Stage 1 cancer. Still needs me to find a piece of spring steel wire and twist up a quick shutter-return spring. I can now lay that thing out on a table and have it back together like a new one lickity-split. Look at the ad. Is this any good? Thanks.

Tom1956 · Sep 5, 2013

Revisiting this thread after conducting speed tests and attempting to correct, I've reached a dead end for now. There is no real way provided on this shutter for meaningful timing adjustments. This leads me to ask a question of perhaps some clock people (of which I am not one). Specifically my biggest question is: over 90 years time, how much spring strength typically gets lost? There are not really many springs in this simple Betax shutter, but I am just about convinced it will never be possible to make the adjustments needed without my fabricating new springs. Would you agree? Here is what I have now: 1/2 ok, 1/5 ok, 1/10=11.5, 1/25=1/33, 1/50 does not exist. Nothing past 1/33. And believe me, I've done a lot of spring bending to get this compromise. The simplistic clockwork-and-escapement mechanism only has one spring and I highly suspect it has no strength remaining to hold against the big hairpin spring that drives the whole shutter.

desertrat · Sep 5, 2013

I have a couple of Betax #4 shutters. The best one appears to fire accurately at all speeds, although I don't have a shutter tester. All your shutter speeds are within half a stop in accuracy, except 1/50. If the shutter has been heavily used, that is as good as it's going to get. IMO, you have a very usable shutter. If you need greater accuracy, you might look into a professionally CLA's Compur or Copal.

shutterfinger · Sep 5, 2013

Play at the pivot where the main lever mates with the shaft it rotates on, shutter blade pivot pins, and delay gear pins all add up in conjunction with weak springs to cause poor speeds. With the tension removed from any rotating part check its side play, shutter blades and delay gears should turn freely with no side play; operating levers should have less than .001 inch side play. Check pins, shafts, and mating holes for roundness, machine and sleeve elliptical ones.

Tom1956 · Sep 5, 2013

Thank you. But I am just about convinced the only way I'm going to be able to get proper adjustment of anything in this shutter is to caliper the 3 springs in question, procure some spring-steel stock, and twist myself up some fresh springs. To that end, if anybody can recommend some proper stock, I'd be all ears.

E. von Hoegh · Sep 5, 2013

Tom1956 said:
Thank you. But I am just about convinced the only way I'm going to be able to get proper adjustment of anything in this shutter is to caliper the 3 springs in question, procure some spring-steel stock, and twist myself up some fresh springs. To that end, if anybody can recommend some proper stock, I'd be all ears.

Piano wire, McMaster-Carr has it. Your shutter, by the way, is behaving normally. Go take some pictures, it's not worth the bother of making new springs.
A properly made spring doesn't go bad anyway. I have and use several wtches 100+ years of age, were springs to weaken with age the rate of a watch (or anything controlled by a balance and balance spring) would become slower and slower. The watch in my pocket today is 101 years old, it has not changed it's rate in the 25~ years I've been using it.

Tom1956 · Sep 5, 2013

Thanks. I intend to use it. But the only way it's behaving even this well is because of all the spring-bending I did to get the springs to play nice against each other. Before, I had .400 for 1/2, and 1/10 all the way past 25, and 1/40 all the way to B. The shutter setting is actually a dial with cam steps, and when it would come to the nest step everything was all mixed up, because of the weak springs. The shutter-return spring for instance doesn't have the strength to hardly move itself, much less the leaves. I've got a copy of
[h=1]Simple Escapement Retard Shutter: Photo Equipment Technician Course[/h]on the way, so I'm sure I'll be back in this thing. At least I can shoot something for the time being though.

Betax #4--hard to repair?

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