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Interviews with Optics Repairers: Cory Suddarth of Suddarth Optical Repair (1 Viewer)


Staff member
The Story Behind the Repair Shop

I was born into a family deeply involved in optics. My father, Jack Suddarth, an inventor and engineer has numerous patents in the ophthalmic machinery industry. I recall having a part time job in high school working around eyeglass processing machinery. Interested in serving my country, I enlisted in the U.S. Navy. I wanted to go into any optical field they may offer. The recruiter offered me a spot in the Navy Opticalman program. Like getting married, I said "I do". The in-depth program went deep into the repair and calibration of optical instruments, and, as you may guess, very deep into the repair and collimation of binoculars. That was back in 1975. I have 12 years in military optics, as well as 15 years as a manufacturing optician.

In 1990 I joined up with a former shipmate and fellow Opticalman Bill Cook at Captain's Nautical in Seattle, Washington. It was there where I discovered the nuances and huge variety of commercial-grade optics. Basically, I was exposed to every name and type of binocular ever made from countries around the globe. It was also while at Captains I got bit by two bugs: birding and astronomy! What a hoot! Like a kid in a candy store! Over 100 binoculars in the display cases, and more than 30 spotting scopes and telescopes set up on display!

After seven years at Captain's, I answered the call of Orion Telescope and Binocular Center in central coastal California. I got to set up the repair and optical testing department, along with product development and prototype machine shop.

Now located in Henryetta, Oklahoma, Suddarth Optical Repair offers repairs on just about every make and model of binocular and spotting scope ever made. Many vintage Bausch & Lomb, Hensoldt Wetzlar, Leitz, Nikon and Swarovski just to name a few. Current makes and models as well such as Eddie Bauer, REI, Zen Ray, Swift, Celestron and too many to mention. If you call Carl Zeiss with an older Carl Zeiss bino, or, a Carl Zeiss Jena model, you will be referred to us. Likewise, Swarovski Customer Service back in Austria no longer services the Habicht series, and those are also referred to Suddarth Optical.

Passing the craft to Eric Suddarth (my youngest son) he handles the lion share of what we call "hand held" binoculars. I do the "big eyes" as well as the esoteric items. My oldest daughter Cat who left the aircraft industry with 20 years as an avionics tech, now works part-time learning the binocular repair craft.

Getting Down to Business: The Repairs

Every glass repaired here at S.O.R. gets collimated on our U.S. Navy Mark 5 collimator. This instrument assures perfect alignment for all users, regardless of their inter-pupillary distance. That is what sets us apart from other so-called repair shops. Collimation is a science, not a guessing game. We frequently re-cement optics that are in need. We also re-skin instruments that have lost their leather covers, and paint to prevent further corrosion if needed. We have decades of experience, proper equipment and trained technicians. Our warranty isn't too bad either. If you get a glass shipped back and it was knocked out of alignment in shipping, we will re-work it at no charge.

The top 3 most common causes for repair are:
1. The bino got dropped.
The fix for this is often easy. We find the problem, ranging from a cocked barrel (on Zeiss style Porro prism models) or a prism jarred loose and that needs to be reset and epoxied in place. Either way, the glass gets placed on our Mark 5 collimator and realigned.

2. Lens haze and stiff or frozen functions.
We get binoculars all the time found by someone cleaning out a closet or garage or even purchased on-line. Time and thermal cycles over many decades deposit a light film or haze on the internal optics which greatly reduces contrast and clarity. The fix for this is more complicated. All the optics get pulled and cleaned. The focusers get cleaned out and re-lubricated. We use a state-of-the-art damping grease for a smooth luxurious feel. Then again, the glass gets collimated on our Mark 5 collimator.

3. The binos got wet and we tried to take them apart.
Along with a disassembly, corrosion often needs to be addressed. Then again a total tear down is needed.

How frequently do we see back-lash problems in the focuser?
That depends on the glass. If it is a newer inexpensive Porro, it’s a design flaw and corners were cut to make the glass cheap. If it is an older Porro prism glass, it's an easy fix. But typically, a glass with these problems more often have other issues to contend with. If a newer low cost roof prism glass suffers from this, it is often a design flaw. Honestly, we rarely get a glass sent in for backlash. More often, it is a focuser that is too stiff.

Is it tricky to source spare parts, prisms, lenses, etc.?
Oh boy, well, first of all, typically a new glass will be out in the field 20 years or more before we see it here, as most problems get handled under warranty. For example, I sold the first Swift Audubon HR/5 series back in the 1990's thru Captain's Nautical when they came out. They are now showing up for service. Parts are available, just need to know where to find. As for scratched lenses from improper cleaning, that can be hit or miss, so many brands have closed down and parts aren’t easy to track down, but really, replacing lenses isn’t a frequent occurrence.

Do coatings get scratched?
While harder than the glass they are deposited on, coatings are evaporated metals, but are applied only a few millionths of an inch thick. Great care needs to be used during cleaning. Grit acts as sand paper, so use canned air or a camel hair brush. Never go at it with dry lens paper. Lens paper is designed to be lint free. Lint is easily dusted off without damaging lens coatings. If you have spilled something on a lens, denatured alcohol and a Q-tip will be better than using your shirt tail or used hanky or tissue. I've not yet seen a coating flake off. But have seen way too many ground off by improper cleaning.

Made in Japan, China, Austria, what's the difference?

I've said for years now, if you have a glass made in Japan, US, or Germany take good care of it! I've been privy to seeing in-depth the step by step cheapening of binoculars. Walmart sells a 10x50 Porro prism glass for $27.97. Guess what? It's cheap! To quote Leif J. Robinson (from his book Outdoor Optics), "There are good optics and there are cheap optics. There are no good cheap optics!"

Never use WD-40 on the focuser?

Well, we use WD-40 here in the shop on a regular basis. But, let me explain. We use it as a solvent on disassembled mechanisms. Not sure I'd recommend spraying on a focuser mechanism. If it gets on internal optics, you'll be giving us a call.

We always use our U.S. Navy Mark 5 collimator. The process is called tail-of arc. Much has been said on-line and in print regarding this task. You-tube videos compel you to attempt this seemingly easy task, claiming you can have it done in minutes! So they say!
The average time here in our shop to complete this task ranges from 20 minute to an hour or longer. This process is eloquently explained in Bill Cook's book Binoculars: Fallacy and Fact. There is just so much more to it, Bill explains the process very well. His book can be found on Amazon.

Cory’s Website: suddarthoptical.com

And below Cory and his daughter Cat, a day in the workshop and Cat being busy!



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