One more time: Tachihara 4x5 front cam loosens up. Solution?

[Ulophot]

I have posted about this before and tried numerous possibilities. Here's a new thought, after having had to shoot with the camera aimed well downwards the other day and having the right-hand cam open completely from the pressure, unbeknownst to me until a two exposures had been made.

What sort of liquid might be applied to the cam and upper washer surfaces to increase friction under pressure? I could live with having to reapply it if it would last for even a day's shooting.

For those unfamiliar with the camera, the cam is solid brass, the stainless steel washer is 0.2 mm thick.

220054

[Doremus Scudder]

Thicker washer?

Or replace the cam entirely with a stud and knurled knob assembly that you can tighten down better.

Can't think of much else.

Doremus

[Ulophot]

Thanks. Makes sense. I might have to get someone do that for me. But your mention made me think about having to figure out how to get the entending bed out to do it, and that reminded me that the back cams lock quite securely, which may result in part from the top plate through which the stud would pass being very slightly un-flat, i.e., convex top-wise, so that tightening the cams flattens the top plate ever so slightly,increasing the pressure against the ca, bottom. I'll have to see if I can figure it out. The camera came to me third-hand (at least) with some signs of misuse. I had a couple of issues addressed in an early repair but not this one.

[Ulophot]

Well, that was interesting. I discovered that the front front standard is removable when the cams are removed. I discovered that a couple of screws holding the guides for the standard to move back and forth on bed had come out very slightly. After tightening them and cleaning the bottom of the top plate that the cams press against the guides, and reassembling, I seem to have achieved a better cam tightening. Time will tell; my experience tells me this may be temporary.

My idea about the plate does not make sense, at least for me to try. It's held on with rivets and toying with it is therefore unwise. I think it's about as flat as it's going to get; so be it.

In the long run, however, since I intend to return portraits with this camera primarily (once we can get through the plague), the bed will tend to be level or not too far from it, in any case.

[ericantonio]

Well, that was interesting. I discovered that the front front standard is removable when the cams are removed. I discovered that a couple of screws holding the guides for the standard to move back and forth on bed had come out very slightly. After tightening them and cleaning the bottom of the top plate that the cams press against the guides, and reassembling, I seem to have achieved a better cam tightening. Time will tell; my experience tells me this may be temporary.

My idea about the plate does not make sense, at least for me to try. It's held on with rivets and toying with it is therefore unwise. I think it's about as flat as it's going to get; so be it.

In the long run, however, since I intend to return portraits with this camera primarily (once we can get through the plague), the bed will tend to be level or not too far from it, in any case.

Awesome!!! I had a 100 year old Korona and the screws everywhere was like that. I hated it. I wasn't a woodworker but I knew if I really wanted to baton down the hatches, I would have to unscrew it all, fill the holes with wood glue or something and screw everything back. I had not time back then or commitment. Sold it to a nice young fellow who wanted to take it to Korea.

Also, for things that need tightening, not just cameras but in general, I usually do flat washer--split washer-- nut. So maybe you can add a flat and split washer to your setup there and that could help it a little more.

[Maris Rusis]

I just checked the front and back locking cams on my Tachihara 45GF camera and note the following:

The cam handles tilt forward (toward the subject matter) to unlock the front standard. It is possible when disassembling and reassembling the cams to wrongly install them backwards so that the handles tilt backward (toward the photographer) to unlock the front standard.

The cam handles are pulled back a tiny fraction past vertical (toward the photographer) when the cam is at maximum tightness. The effect of this design is to "wedge" the cam even tighter if the front standard is pulled forward. The picture of the cam furnished by the OP shows the cam handle way past vertical. This should not be possible.

The locking cams on the back standard swing plates work the opposite way with the handles tilting back to unlock the swing. Again, maximum locking force arrives when the cam handles are a tiny fraction past vertical but this time in the direction of the subject matter.

The OP's post of 21 Feb 2021 also shows a Tachihara front locking cam with the handle way way past vertical. This should not be possible if the adjustment is correct.

[Ulophot]

Maris, thank you. Since the manual, such as it is, really gives no clue about this (or much else), I certainly defer to your expertise. I have, along my journey with this camera, tried adding more and thicker washers, without success, but I shall try again based on your recommendation. Also, according to your description, my back cams are on the opposite sides from where they should be. I'm not sure why this makes a difference, but I'll take a look into it. (P.S.: would love to see more of your outstanding work here again.)

ericantonio, thank you also, but there is no room for "flat washer--split washer...." Note that I mentioned that my washer is 0.2 mm, so thin that thy are obtainable only through hobby shops that deal with a lot of miniature modeling.

[Ulophot]

Maris, I just tried your suggestion for the front cam. The closer I get towards a more vertical closed position, the less stable it is. I tried different combinations of washers to achieve this -- not having a single one of sufficient thickness -- but even just two 0.5-mm ones gave the same result. Why yours works this way and mine not is beyond my comprehension; I am not a builder or mechanic of any kind. I returned to the single 0.2-mm washer, which lands my closed position as shown below. The cam has not reached maximum width by this point and thus still reaches a stopping point.

220060

I know that the Tachihara 4x5 was made in a number a configurations with various modifications -- some more significant than others -- over the years it was produced, and perhaps your camera is slightly different from mine in some respect we're not including as a potential factor.

[Maris Rusis]

Interesting! Years ago I was a sales engineer marketing Tachihara camera in Australia. I got to see many of them and from unit to unit they were very consistent. I still have two 45GF for personal use. Their serial numbers are from 1993 and are only 33 units apart. And yes, the locking cams in both cameras work identically just like in my previous post.

Just for sake of experiment I added a very thin washer to one of the front cams and found the fully tight stopping place of the cam lever is exquisitely sensitive to washer thickness. Any increase in thickness means the lever stops before vertical. Any reduction in washer thickness means the lever goes past vertical to get a tight lock. I suspect Tachihara specified cam and washer as matched components.

I also discovered that the force exerted by the cam on the washer is concentrated on a very small area so a thin washer is easily bent and the cam lever has to go further to get a lock.

Amusingly, I also found using an ordinary washer with a bigger central hole doesn't work well. The high force cam looks for the edge of the centre hole and bends the metal a little bit. Again, the cam lever has to go further to get a lock.

[Sean Mac]

These were referred to as "over center" cams when I was a student.

They have to go past the point of full compression to lock.

[Ulophot]

Sean, that makes sense to me, but clearly was not the design in these cameras, as countless photos of them, and users, attest. My only guess is that unlocking might have been considered a bit too jarring, or a low position of the small cam lever inconvenient.

Maris, you certainly know the cameras better than I. Mine has no serial number -- anywhere -- for whatever reason, as attested also by the repairman. I have seen photos of some that did not have toggle cams, some with apparently fewer movements.

In any case, the maximum room I have for washers is about two 0.5 and perhaps one 0.1, before I'm no longer able to align the horizontal holding screw with the hole in the vertical post. As I said above, I've tried various combinations. for a while until recently, two 0.2-mm washers on each side seemed to be the ticket; now just one seems to be best, lowering the camera lever position at closed as shown immediately above. These thin washers do indeed get bent. The internal diameter is 5 mm, outer is 7, though in my pack of 0.1, 0.2, and 0.5 from Japan (called stainless steel shims) there appears to be some slight variation in the width of the band. The contact surface of cam to washer is indeed quite small, and both surfaces are polished quite smooth.

The only other thing I can think to note, is that the thinner, outer part of the steel guide rail, not being screwed down to the bed like the inner length, bends just slightly up if slight forward pressure is applied to the front standard, making a faint click when it comes back down on the bed, even when the cam is closed. This simply allows a tiny bit of play in the front standard, though it has not effect on operation normally (i.e., without aiming the camera severely down as I did recently).

Probably there isn't much else to explore here. These are hardly calibrated Sinar P mechanisms (which would not make my photography any better), and wear and tear by inexperienced or rough users, which my camera seems to have experienced long before arriving in my hands at an unusually low price, may have been enough to push several factors minimally out of original spec, just enough to make the difference.

Again, I am grateful for all the help.

[Maris Rusis]

It is a surprise that a Tachihara camera has no serial number. Usually it is hand written at the back of the bed of the camera. Unlock the rear standard and push it forward, advance the focussing rack, look down, and the S/N should be visible. I think Michio Tachihara himself checked each camera before it went out.

The Tachihara Mfg. Co. Ltd. had an alter ego as the Professional Camera Company which made "blank" cameras of the same design for any enterprise that wanted a house brand camera. The Calumet Wood-Field 4x5 is an example.
There were many design variations since Masao Tachihara founded the company in 1934 but by the 1970s the physical design stayed essentially the same with variations in the colour of the wood, bellows, and metal work.

There should be a label under the carry strap with the words "Fiel Stand" on it. I'm told that "Tachihara" translates literally as "man stands in the field" hence the (deliberately) mis-spelled label.

[Ulophot]

Okay, Maris, you put me to the task again, and again I discovered something -- enjoying which is always better than feeling embarrassed. While there is no Fiel Stand, or label at all under the strap -- the one label is "Hope Tachihara" along with the full company name, on the back, like the one grabbed from the web shown below-- there is, after all, a number, overlooked till now. Pressed into the wood at the back under the varnish is the single number "5". Does that tell one (i.e., you) when it was made? I'd be interested. Thanks for your help, Maris.

220079

[Vaughn]

Those cam handles can break if excessive force is used. One of the reasons these cameras were not successful as loaners to students where I worked.

[Ulophot]

Fortunately, Vaughn, I am a moderate person (at least, physically), and I like my equipment and do my best to treat it well so that it will reciprocate in its own way.

That would be quite a bit of force to break the cam handles, I should think. Though I do remember the frustration of the poor gents who signed out equipment at the insane-asylum-disguised-as-a-leading-art-college I attended for a 2.5 years c.1971 before making for the exit. The equipment surely suffered at the hands of uncaring students.

[Vaughn]

Great cameras for the individual -- but it is not as solidly built as a Deardorf or other heavier wood field cameras. The issues I had with the cams made me consider the cams to be unneeded weak points in the design.

I had much better luck with the Horseman WoodFields -- not as pretty (beautiful) as the Tachihara, but simpler and a stronger build without adding weight. I remember a student or two who would not check out the Tachihara -- they thought it was too good-looking and they were afraid of scratching it or otherwise damaging it.

[LabRat]

Fortunately, Vaughn, I am a moderate person (at least, physically), and I like my equipment and do my best to treat it well so that it will reciprocate in its own way.

That would be quite a bit of force to break the cam handles, I should think. Though I do remember the frustration of the poor gents who signed out equipment at the insane-asylum-disguised-as-a-leading-art-college I attended for a 2.5 years c.1971 before making for the exit. The equipment surely suffered at the hands of uncaring students.

You don't have to have superhuman strength to wreck some stuff, it's built into the (poor) design... And not "overused"...

In my stint in education gear service, saw many items (even new out of the box) that the factory adjustment range was so narrow (due to poor design/construction) that function barely worked in the real world... 4X5 camera backs that the holder slot was so narrow that when a thick holder (like a Polaroid) was used would slightly bend outward from every insertion that the GG panel would barely close with proper pressure, or even fall right off eventually, leg locks on popular tripods would slightly stretch causing legs to not lock firmly, new popular 4 blade easels that were misaligned so prints were always crooked on paper with slots not big enough to hold flat DWFB fiber based paper, and on and on... Proves the old saying "just because it's an idea, not necessarily a good one"...

Don't know your locking mechanism, but thin fibres washer from Ace hardware might fit in that give you some added locking pressure (if loose)...

Good luck!!!

Steve K

[Maris Rusis]

Okay, Maris, you put me to the task again, and again I discovered something -- enjoying which is always better than feeling embarrassed. While there is no Fiel Stand, or label at all under the strap -- the one label is "Hope Tachihara" along with the full company name, on the back, like the one grabbed from the web shown below-- there is, after all, a number, overlooked till now. Pressed into the wood at the back under the varnish is the single number "5". Does that tell one (i.e., you) when it was made? I'd be interested. Thanks for your help, Maris.220079

I'm pretty sure that Tachihara shut their business in 2013 as no family successors were enthusiastic in continuing. The 300 year old Hidaka Shuri Cherry Blossom wood was also getting rare and really expensive and arguably better and cheaper cameras were coming from China.

A visitor to the Tachihara factory commented that the place was smaller than expected, only five workers, and crammed with cartons of semi-complete cameras, jars of metal components, and included a few small islands of space for the machine tools. Apparently 4x5 cameras were made in batches of a hundred and 8x10s were made in batches of seventy. The workers claimed ( Japanese perfectionism?) no two were exactly the same. A 4x5 was scheduled to take four months from raw wood to final completion while a 8x10 took eight months. A "pride of work" specification was that camera bodies should last 50 years in normal use and the bellows 30 years.

The number "5" pressed into the wood (none of my Tachis have it) is probably a component identification number to guide correct assembly; no date information there.

Tachihara like many small Japanese companies had no one who could write or speak English so they used a export agent to handle English language brochures, instruction sheets, export paperwork, and spare parts requests.
Hence the entity "Hope Tachihara - Tachihara Professional Technical Camera Co. Inc." became the interface between the factory and the world outside Japan. All my Tachiharas 4x5s and 8x10s have this sticker.
If you are in Tokyo you could visit where they were: Tachihara Camera Mfg. Co., Ltd. 3-17-8 Toshima, Kita-ku, Tokyo 114-003.