Nikon Series S fine focus problems

Have questions about the equipment used for macro- or micro- photography? Post those questions in this forum.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Ichthyophthirius
Posts: 1152
Joined: Thu Mar 07, 2013 5:24 am

Nikon Series S fine focus problems

Post by Ichthyophthirius »

Hi,

I have bought a Nikon S-Ke microscope which suffers from damage to the fine focus. The problem of the nylon gears in these old Nikon microscopes being frequently damaged is well known, so I was disappointed but not surprised.

However, I'm wondering if it was worth trying to repair it. For that I was curious if somebody here has tried that before. I couldn't find any documentation on the web. And does anybody know exactly what part is frequently damaged in the fine focus? Are there any drawings of the gear box available?

Kind regards, Ichthy

lothman
Posts: 957
Joined: Sat Feb 14, 2009 7:00 am
Location: Stuttgart/Germany

Post by lothman »

I did a replacement of the plastic pinion on a Nikon Labophot microscope.

I got a steel pinion, drilled it to the diameter from the shaft and glued it (Loctite) to the final Position.
See here:
http://www.photomacrography.net/forum/v ... t=labophot

Ichthyophthirius
Posts: 1152
Joined: Thu Mar 07, 2013 5:24 am

Post by Ichthyophthirius »

Hi,

Thanks for your reply. The gears in the Series S microscope seem to be very different from the ones in the Labophot.

I removed the outer parts of the focus knobs and this is what I saw: The plastic gear wheel is broken in at least two places.

I would like to have a closer look, but I don't know how to dis-assemble is further.

Does anybody know how to remove the broken gear? I'm hoping to get a replacement laser-cut from plastic or metal.

Kind regards, Ichthy

Image

Choronzon
Posts: 384
Joined: Sun Feb 21, 2010 9:14 am
Location: Chicago USA

Post by Choronzon »

To remove, first, take off the other fine focus knob on the other side; there is a wave washer between two celluloid washers that control the fine tension acting on this knob.
Next, unscrew that large aluminum ring that covers the broken gear; it unscrews counterclockwise with a pin spanner.
Then you can slide out the entire fine shaft that the gear is attached to.
There are 4 very small set screws that hold the gear onto the shaft, loosen those and slide the gear off.
PM me if you need a new gear
I am not young enough to know everything.

dolmadis
Posts: 899
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: Nikon Series S fine focus problems

Post by dolmadis »

Hi all

Resurrecting an old thread and for an old issue that I would like to solve several years on.

I have been offered an S-Ke but it will need a replacement Spur Gear. Without it I will pass.

Does anyone have a 3D to print or to purchase please?

I don't think my skills will go to pressing on a brass one though.

Thanks, John

Smokedaddy
Posts: 1951
Joined: Sat Oct 07, 2006 10:16 am
Location: Bigfork, Montana
Contact:

Re: Nikon Series S fine focus problems

Post by Smokedaddy »

Ichthyophthirius wrote:
Wed Aug 13, 2014 2:17 pm
I have bought a Nikon S-Ke microscope which suffers from damage to the fine focus.
Sure would be interested in seeing a photo of the gear once removed.

-JW:

Smokedaddy
Posts: 1951
Joined: Sat Oct 07, 2006 10:16 am
Location: Bigfork, Montana
Contact:

Re: Nikon Series S fine focus problems

Post by Smokedaddy »

dolmadis wrote:
Sun Apr 03, 2022 2:16 am

Does anyone have a 3D to print or to purchase please?

I don't think my skills will go to pressing on a brass one though.
It should be a problem installing brass gear IF that's the way you want to go. You don't actually have to 'press' it on. The tolerances are that tight and the need for Locktight.

As for 3D printed gears, there are several OpensCAD 'gear generators' on Thingverse but I don't know how well something like we're talking about, will print. I did this way back in 2016 for my Optiphot.

viewtopic.php?f=25&t=38267&p=239527&hil ... ar#p239527

-JW:

dolmadis
Posts: 899
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: Nikon Series S fine focus problems

Post by dolmadis »

Smokedaddy wrote:
It should be a problem installing brass gear IF that's the way you want to go. You don't actually have to 'press' it on. The tolerances are that tight and the need for Locktight.

As for 3D printed gears, there are several OpensCAD 'gear generators' on Thingverse but I don't know how well something like we're talking about, will print. I did this way back in 2016 for my Optiphot.

viewtopic.php?f=25&t=38267&p=239527&hil ... ar#p239527

-JW:
I found this article about the procedure http://www.microscopy-uk.org.uk/mag/ind ... nikon.html

Seemed to require some skills !!
The final challenge is to press on the new brass gear. This can be done by one of three methods: Tapping the carefully-sized new cylindrical gear onto the bearing (recommended by Mark), using concentric rings to press or tap on the gear, or employing the thermal expansion method.

A combination method proved most effective. I cooled the bearing for an hour in the freezer, then heated the cylindrical brass gear on a stove element until it was just uncomfortably hot. Holding the gear with a tea towel, it could be pressed half way onto the cold bearing with firm finger pressure before temperatures equalized and it seized in place. This oriented the two pieces. I then placed the assembly flat on the edge of a counter and tapped the gear gently with a small hammer, rotating with each tap. This proved effective but slow, so I grasped the edges of the gear and bearing between the jaws of a pair of plumber’s pliers. Applying gentle pressure at intervals around the gear and bearing, rotating the assembly between each gentle squeeze, quickly but gently pressed the gear onto the bearing and leveled the two surfaces. The gear proved to be very carefully machined and was easily guided to a smooth and precise fit.

The whole shaft and gear assembly was then carefully cleaned, lubricated with a sparse amount of grease, and reinserted into the scope. The washers, right cover, and knobs were quickly replaced. The reassembled fine focusing mechanism now moved silkily, with absolutely no hesitation. The finished scope.
Best, John

ray_parkhurst
Posts: 3413
Joined: Sat Nov 20, 2010 10:40 am
Location: Santa Clara, CA, USA
Contact:

Re: Nikon Series S fine focus problems

Post by ray_parkhurst »

I replaced the fine focus gear on an Optiphot focus block and it came out very well. Unfortunately, I never put the focus block to work, and it sat unused for a decade. I am finally making something of the system and will post something about it when done, but meantime you might want to check out my "beta test report" for the pinion I got from Lothar:

http://www.photomacrography.net/forum/v ... us#p218945

dolmadis
Posts: 899
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: Nikon Series S fine focus problems

Post by dolmadis »

Several months ago I used several search engines to see if a kind person had published a 3D printed version of the Fine Focus Spur Gear for Nikon model S microscope.

A few references from some years ago that some people had but they lead nowhere.

As I have come across an interesting way of potentially acessing the back focal plane for experimentation with my incomplete Nikon IPC (a story for later when I have news) I thought that I would look again at the surviving brass commercial replacements again by searching the engines.

To my great surprise I found not a new reference to a 3D print version but one which had not turned up earlier. I am posting so other members can access it if necessary.

https://www.thingiverse.com/thing:5005716/files

I am hoping that it will be easier to install than a brass one.

But what material should i use? I don't have a 3D Printer so I use the print bureaus in the UK which have a great range of alternative materials.

Would welcome suggestions (and any encouragement that it will be quite easy!!)

Best, John

dolmadis
Posts: 899
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: Nikon Series S fine focus problems

Post by dolmadis »

Update.

The Thingiverse file produced a spur gear which did not fit properly and snugly over the criss crossed brass collar.

A commercial 3D printing bureau in the UK very kindly modified the .stl file and printed me one in Natural Rigid Resin 4000.

Fits perfectly and installed back to full working condition.

Best, John

Nikon Model S
Posts: 3
Joined: Sun Feb 18, 2024 4:11 pm
Location: N.Ireland

Re: Nikon Series S fine focus problems

Post by Nikon Model S »

Hi. Just got a Nikon Model S for my son who just turned 10.
He loves it so much.
Though focusing wheel totally locked.
I stripped the focus wheel.and shaft etc down and noticed the broken nylon fine focus wheel too.
Going to clean the mechanism all down, regrease and I see the 3d printed file listed above.
I'm going to get that printed off and pressed on.
Just a query..Who printed yours for you and what mod did they do to get it to fit better?
Thanks for your help
Mark

dolmadis
Posts: 899
Joined: Wed Dec 07, 2011 1:51 pm
Location: UK

Re: Nikon Series S fine focus problems

Post by dolmadis »

Hi

sgd3d.co.uk
SGD, Unit 20, Pottery Court, Bulwell, Nottingham, NG6 8YN

One printed locally by a friend did not fit the brass hub on which the gear is mounted until it was modified by the bureau.

"inner diameter modified to be smooth and concentric at 24.2mm (0.1mm clearance)."

Do check your measurements as they might vary on time of manufacture and exact model of the microscope.

I "think" that their file name was "FineFocusSpurGear [MOD].STL"

Good Luck.

John

Nikon Model S
Posts: 3
Joined: Sun Feb 18, 2024 4:11 pm
Location: N.Ireland

Re: Nikon Series S fine focus problems

Post by Nikon Model S »

Thanks so much John for the info. What kind of price roughly at the time you got yours were they charging.not sure if it's worth getting two made.
I have to see if I can get the course focus rack fixed too as the whole stage was jammed and the long pinon focus rod would not come out.
I was tapping it hoping it would push through but it damaged some of the teeth in the rack.
I'll file the bad bits straight again. Should be ok as there as a good width on the rack the the pinon can still slot into as it moves up and down.
Not sure if a 3d printed focus rack would work or it may be not strong enough.
Regards Mark

Nikon Model S
Posts: 3
Joined: Sun Feb 18, 2024 4:11 pm
Location: N.Ireland

Re: Nikon Series S fine focus problems

Post by Nikon Model S »

Hi John.
I got in contact with SGD3D and they said,

'Unfortunately we’re not allowed to share other customers order details or files without their direct permission.
I’d suggest reaching out to this individual and see if they can send you the files'

I sent them the unmodified file after that and the specs so smooth the inner. I still need to measure the diameter of the brass hub with a vernier caliper.
I'll see if they get back to me unfortunately tomorrow.
Regards Mark

Post Reply Previous topicNext topic