Use of cordless screwdrivers in the repair of photographic equipment

[Andreas Thaler]

Up until now, I have only used my cordless screwdriver to drill into screw heads and unscrew screws.

I am wondering whether the device has any advantages for jobs that I have previously done manually with a screwdriver. In particular, loosening stuck screws. The torque should be higher than that of (my) hand.

But I also see it as a way to make work easier when loosening screws in general.

I spent a long time looking for JIS cross-head screws bits and found them. At least I assume that they are JIS, this is not always clearly stated.

I will gain more experience „with the machine“ on the next project (removing the mirror box of a Nikon F4).

I am cautious when screwing in screws because I can better control how tightly I tighten the screw by hand.

Do you have any experience with cordless screwdrivers in this regard?

 

[forest bagger]

I use only my hand powered tools instead of motorized tools to remove screws in cameras and lenses.
The power of my hand is still more than sufficient for removing screws up to size 2 JIS.

I tried to use an electric powered screwdriver in counter clock wise mode to remove some stubborn srews in an old mechanical lens some days before, but failed entirely - the head of the screw was distroyed totally.

Since then I'm looking for an impact wrench like it is used to mount and dismount tires on cars in miniature size but haven't found any...

 

[koraks]

The torque should be higher than that of (my) hand.

I find that with the small screws in lenses and cameras, the torque I can apply with my hands is already enough to totally destroy stuck screws. As a result, I don't really see the benefit in using power tools here.

 

[forest bagger]

It's not the amount of torque but the intermittent, pulsating force of an impact wrench which loosens the stubborn screws I think.

 

[Andreas Thaler]

I can turn my Bosch very slowly and in a controlled manner; it has two gears.

This has proven to be useful when unscrewing screws.

I will report back.

 

[MFstooges]

Xiaomi Precision Screwdriver Set, 24 Magnetic Driver Bit Set, Pocket Screwdriver Tool Set, Mini Screwdriver Kit, Repair Tool Kit for Electronics https://a.co/d/6lMgXkK

 

[xkaes]

It's hard enough to get the angle of the screwdriver perfectly aligned with the screw without adding the size of a power tool. For me, that pretty much guarantees that the angle will be OFF -- and that's the major reason for stripped heads. If the screw/bolt is really stuck, try loosening solvents/processes first.

 

[Kino]

In my experience, stubborn screws either need a penetrating oil or a light solvent soak, rather than more turning pressure.

Too easy to shear-off or deform the head of the screw.

Sometimes, a light shock to the screw head will help...

 

[4season]

Power drivers are used by camera manufacturers, but they are more specialized tools which pick up and hold the fastener, and precisely torque it. At 1:29 in this video shot at Sony's Thailand facility, you can see one of the workers using such a tool - it's amazingly quick:

 

[Light Capture]

Industrial micro screwdrivers are available. Not at your usual tool stores though. Quite expensive too.
They won't help with stubborn screws. They're of no use for regular service. Some of them have preset and some have adjustable torque.
They're typically set for only one torque when in actual use.

Impact or impact drivers aren't the best choice if there's any sensitive optical assembly.
For example, Leica service is known to use wood blocks and small hammer to correct and calibrate the focal flange distance. I'm using shims and other methods for this.
Otherwise, if you need to use mechanical methods in this case rangefinder assembly needs to be removed first as there are adhesives there that keep optical components in place.
Some of them can be disturbed. There are other places where impact and precision hammers are called for but that should be really kept to minimum.

All other previously discussed techniques will work. Solvents, penetrating oil, heating, slight impact to the screw head (with no sensitive optical assemblies nearby) and drilling out as a last resort.
Most important part is having proper and good quality tools.

With the right tools it's really rare to have an issue.

Newer cameras (newer than 70's or 80's) started having thread lockers instead of lacquer. Even though they're not that hard to remove with the right tool, they're going to cause slippage with the screwdrivers that don't fit well.
Some of these screws with thread locker applied had too much of it applied and will be very difficult to remove. Luckily, this is a very rare occasion.

Most of the issues when they happen for me are actually user related. That's when I forget and don't put enough steady force to keep the tool on the head of the screw when it's first touched.
If the tool slips there with moderate force, it will cause slight damage to the head and that will make it much harder to remove. Luckily this is also a very rare occasion but it takes time to develop the feel for the exact force needed for different screw sizes and different head types.

 

[DWThomas]

Having twisted the heads off #10 stainless steel deck screws once or twice, I would not consider my power screwdrivers for camera work. I far prefer modest but clean and precise small hand tools for most fine work. As noted upthread, judicious use of solvents or heat may help with thread lock situations, also use of very well fitted screwdriver blades and applying pressure to keep the blade seated.

 

[miha]

Power drivers are used by camera manufacturers, but they are more specialized tools which pick up and hold the fastener, and precisely torque it. At 1:29 in this video shot at Sony's Thailand facility, you can see one of the workers using such a tool - it's amazingly quick:

Are these ladies in production standing for the entire shift ??

 

[Andreas Thaler]

My plan is to let the small Bosch do the work of unscrewing screws.

Bits can be turned in slow motion and I am excited to see how the force can be transferred to the screw heads and controlled.

With stuck screws, it should at least save me the pain in my hands that comes with using a screwdriver. Over-tightening obviously makes no sense.

I am a fan of these small motor tools and also like to use my two Dremels where it makes sense.

I already have expertise in milling screw heads, much to the dismay of many participants here

see

Stubborn screws: Milling out screw heads, recommendations for milling cutters

Stuck screws, secured with adhesive, that I can't loosen with solvent or heat have put one or two of my projects at risk. Because if a screw doesn't come loose, you can't go any further, e.g. dismantling a lens bayonet. To make progress, I tried using a screw extractor and a drill, but that...

www.photrio.com

 

[Andreas Thaler]

With the right tools it's really rare to have an issue.

In my experience, screws in some bayonets of Nikkor MF lenses are the hardest kind; I also encountered real devils in the Canon T90, Nikon F4 and a Tamron zoom.

I used all the methods I know of that have already been mentioned here, with the exception of a hammer. No chance.

 

[DREW WILEY]

The little blue 12V Bosch cordless drill you show is an excellent cabinet shop or light construction item made in Malaysia. I have their full set, including the impact and right angle drivers, which Bosch gave me for sake of an endorsement. But it's certainly not ideal for camera or other sensitive technical repair purposes.

What you need is an especially linear attachment rotation with minimal wooble, along with an especially sensitive clutch to avoid stripping small screws. Only the German Festool 12V system would provide that, which is significantly more expensive. Otherwise, you better stick to doing it by hand. The only exception, where a Bosch impact driver or drill might be suitable, would be to remove a stubborn screw in reverse mode, or else use it just to drive a screw most of the distance, and then do the final tightening by hand. That's how I've often used it in relation to camera or darkroom gear. An impact driver works much better in this respect than a drill.

Still, you need to be careful about bits themselves. It looks like you have indeed selected quality Japanese driver bits; but I am unfamiliar with that specific brand. When it comes to drill bits, I'd recommend domestic cobalt steel ones. Getting a good center hole into a small screw for sake of a tiny easy-out or screw extractor, is a demanding task. I only use my small Sioux industrial air drill for that kind of purpose, because it has almost no runout wobble at all (cheaper air drills are a different story, sadly). And again, it's hard to find good quality screw extractors unless you shop at a true industrial supplier like McMaster. Once a cheap one itself breaks off inside a screw, you're really in trouble.

Dremel tools? Everyone needs one of those sooner or later, unless you have a more serious die grinder system.

Want the finest in a tiny yet powerful cordless impact driver or drill. Try the Makita aerospace version. These are programmable to within 2 or 3 % preset torque value, and have flame and explosion-proof batteries for sake of combat conditions. I don't know their current price; it was about $8,000 apiece 15 years ago, or double that for one ergonomically adapted for space gloves. Every DIY home rocket ship shop needs one. Most of the ones in use in this area are at the Tesla/Space X plant.

 

[Andreas Thaler]

Thanks for all the information!

I'll do a few exercises with the Bosch tomorrow on cameras for spare parts.

Loosening screws, observing tool behavior and control options.

I'll report back.

 

[Steve906]

I would say no.. actually no.no.no.. I have exactly the same drill driver shown and wouldn't let it within 10ft of a camera or lens I was working on. Nice bit of kit for other stuff but torque and speed is just not controllable enough, even drilling totally stripped screw (by PO using such a device?) I would use a handheld pin chuck. My set of screwdrivers for just about everything JIS are Moody/central tools 58-0319.

 

[Andreas Thaler]

Dremel tools? Everyone needs one of those sooner or later, unless you have a more serious die grinder system.

I have had very good experiences with the small Dremel Stylo, which can be used for the most delicate work, e.g. polishing.

The powerful 4250 is suitable for machining metal parts and for milling, among other things.

They are tools like any other, i.e. the user decides what to do with them and how, and is of course responsible for success or failure.

I am very relaxed and like to try things out. Everything is DIY, i.e. any means that brings success is acceptable.

I bet that the little Bosch will not disappoint me tomorrow. Unscrewing a Phillips screw in slow motion is no problem with it, nothing can go wrong as long as I control the process.

We will see.

 

[Light Capture]

In my experience, screws in some bayonets of Nikkor MF lenses are the hardest kind; I also encountered real devils in the Canon T90, Nikon F4 and a Tamron zoom.

I used all the methods I know of that have already been mentioned here, with the exception of a hammer. No chance.

Completely agree about Nikon bayonet screws. Some of them are really bad. Some heating and well fitting screwdriver usually does the job but there is a stuck one more often than most of the others (ends with a screw drilled out). I'm actually not using powered drill or mill when this is needed. Most of these screws are soft and can be easily drilled out with the hand operated pin vise with the drill chuck.

Hammer is widely used to loosen stuck screws in almost any mechanical service but my assessment is that it's very rarely safe to use in that manner on cameras or lenses (exceptions are noted in service manuals as well as how exactly to use it). There is some slight freedom if you're able to remove optics and electronics with only mechanical parts left but I would be very careful there as well. Hammer in question is a small precision watchmaker/jeweler hammer. It's usually used with the staking set for fine riveting. On cameras staking sets are used often whenever riveting is required. For example on some cameras different latches or flash sync connectors are riveted. Same on the shutters. It's also used to repair shutter or aperture blades where riveted pin falls out. Sometimes the old one can be riveted back if it's not lost and sometimes new one needs to be made.

Powered drill of any kind is going to slip at some point and scratch or mar something. Not something I can afford to happen.

 

[DREW WILEY]

A precision electronic drill press can be handy for delicate work, along with suitable vises. But those are not ordinary shop drill presses. You have to pay a lot more for them.

 

[Andreas Thaler]

Unscrewing screws with the small Bosch

A decommissioned Canon T90 is used as a test subject. The battery compartment has to be unscrewed, as well as the long metal plate around the tripod connection.

Three Vessel cross-head screw bits are used, which I assume correspond to the JIS standard. I estimate the sizes to be 000, 00 and 1.

Twelve screws in total, none of them are tight.

Slightly smaller than my Vessel 00 screwdriver.

The bit grips securely into the screw head profiles and the screws are loosened in no time.

For the two screws on the chassis bottom I need the longer screwdriver because the bit is too short.

The battery compartment is off. Much quicker than by hand with a screwdriver.

Even partially loosening the two screws for the backdoor lock with two turns is no problem.


Conclusion

• The screws were removed quickly, safely and without causing any damage.
• It really made work easier.
• I only had one stuck screw that at least resisted the screwdriver without me trying to use force. With the Bosch it worked perfectly in slow motion.

 

[Steve906]

Basically then, conclusions were drawn before posting original question?
I can't see the need for speed in one off repairs.
Twelve screws 'none of them are tight' ? so testing what exactly?

 

[Andreas Thaler]

On this occasion I noticed that all the screws around the bayonet were loose. Perhaps due to vibrations during use?

I'll keep this in mind for the next T90 project.

Bonus: Another bayonet ring to activate the aperture when nFD lenses are removed


+++

All information provided without guarantee and use at your own risk.

 

[Andreas Thaler]

Basically then, conclusions were drawn before posting original question?
I can't see the need for speed in one off repairs.
Twelve screws 'none of them are tight' ? so testing what exactly?

It's about using a cordless screwdriver for camera repairs; tight screws are one option:

I am wondering whether the device has any advantages for jobs that I have previously done manually with a screwdriver. In particular, loosening stuck screws. The torque should be higher than that of (my) hand.

The device takes the strain off your hand and saves time. That's not a disadvantage.

If I find a stuck screw, I'll update here.

 

[4season]

No wonder that some factories can operate so efficiently: