binocular body material (1 Viewer)

I searched the BF forums for a thread about this topic (using the word: Polycarbonate ) and could not turn up a thread. So here it goes. Metallic body material ( some kind of mag alloy, or aluminum) vs plastic (Polycarbonate & whatever it is Zeiss uses in their FL line). I understand the virtue of the plastic is lighter weight, all other things being equal. But what is the virtue(s) of the metals?
Does the body material relate in anyway to alignment/holding alignment, or in any way to general durability?

I own several pairs of porros that are polycarbonate and they seem strong, but I havn't put them through any sort of abuse and they cost less than $300 US new. I don't think I would pay 7 times as much for alphas made of plastic.

Martin

Purple Martin said:

I own several pairs of porros that are polycarbonate and they seem strong, but I havn't put them through any sort of abuse and they cost less than $300 US new. I don't think I would pay 7 times as much for alphas made of plastic.

Martin

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I have some car bins, from Walmart, that cost me $9.99 and have a full metal body, so using metal probably isn't a cost issue.

My FL's, now rigerously used for over a year [with lots of bumps and a few small drops along the way] are like new and they still feel nice and light in the hand. They are rubber-covered anyway, so any tactile difference is all down to lightness.

My primary binoculars are magnesium, titanium, FL glass and lots of other metals and a little plastic for lubrication. In sub zero weather last January in a group of 20 birders my Leica bins were the only ones that focused with one finger effort at temps of zero F .

I also own the Pentax 10x28 DCF MP (Magnesium construction).
In addition I own the successor the Pentax DCF LV 9X28 which is polycarbonate construction.

I like prefer the positive metal feel of the DFCMP BUT use the DCFLV more because it has better optics (its also lighter weight and submersible too). It’s a grudging endorsement. based on only a few years of wear. Check back in 10 years and I will provide an update. Ha ha, But you have me curious and I will take them out this winter and see how they perform.

The only other polycarbonate binocular I have used in extreme cold is the Zeiss 10X25 Victory and it worked perfectly. No optical distortion and only slight stiff focus due to cold. (not a problem). I was able to ID Hooded Mergansers and Buffleheads easily in frigid 10F wilderness over a ½ mile away while hiking..

Like you I am curious about other binocular users experience using relatively new material. Prior reports of users in harsh conditions were favorable. Would love to know more about the longevity of the material.

Considering the lightness of magnesium, I don't see the relative benefit of using plastic to save an ounce or two. Especially at $$$ prices.

Martin

The Zeiss FL, made of glass fiber reinforced polycarbonate, has a pretty good record for bump taking. Mine works fine, but I have not abused it. There was the case described here on BF, however, of an FL owner who tripped and landed on his FL with his full weight, shattering the body. If that had been a Leica, I reckon he would have been seriously injured. I ask you, what's worse?
Ron

ronh said:

I ask you, what's worse?
Ron

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Geez, Ron. A broken rib or a broken binocular. That's a tough choice.

Martin

Purple Martin said:

Geez, Ron. A broken rib or a broken binocular. That's a tough choice.

Martin

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Not really. I broke 2 ribs a few years back. :eek!: Would much rather broken binos :t:

jaymoynihan said:

Not really. I broke 2 ribs a few years back. :eek!: Would much rather broken binos :t:

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I agree. Especially, as my binos are insured.


Martin

ronh said:

The Zeiss FL, made of glass fiber reinforced polycarbonate, has a pretty good record for bump taking. Mine works fine, but I have not abused it. There was the case described here on BF, however, of an FL owner who tripped and landed on his FL with his full weight, shattering the body. If that had been a Leica, I reckon he would have been seriously injured. I ask you, what's worse?
Ron

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Ron:

Just to offer another opinion, I suppose if it had been a Leica, or any other,
with a stronger construction, it would have deflected the fall, and both the binocular and the user may have just turned
out fine.

So then it is a moot point.

Jerry

jaymoynihan said:

I understand the virtue of the plastic is lighter weight, all other things being equal. But what is the virtue(s) of the metals?
Does the body material relate in anyway to alignment/holding alignment, or in any way to general durability?

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Jay, all things being equal (thickness, form etc), the metals would exhibit better stiffness /resistance to bending stresses etc. and should therefore be dimensionally more stable. I'd be interested to see some testing data in relation to this if anyone can dig some up (...I think ronh has already made some mention of stress induced prism faults somewhere? on the 10x43 Zen -Ray thread? - it would be interesting to see if that is purely fixing related, or the result of stress and strain transference from the chassis...)

As I've said elsewhere on BF, not all of us need our bino's /camera's to double as grizzly bashing implements.........so the need for so much weight in everything is puzzling (and not just a little frustrating)

It's got me stuffed why there isn't more advanced materials engineering.........such as carbon fibre - it's sure as heck not cost - 'cause at the prices some brands charge and the glacial pace of development, I'd say there's some healthy ROI's already.

Carbon fibre can be combined in composite form with magnesium /titanium skeletons /honeycombs much the same way as steel reo is used in concrete, and offer significant weight reductions over today's offerings. At a guess I'd say the lack of development in this area has to do with legacy investment in diecast magnesium technology and processes.

The market seems ripe for revolutionary picking!

Chosun :gh:

_____________________________________________________________

Thats the thing about infinity........its always at least 1 more than you can imagine.....

Very interesting Chosun

The material used by Zeiss in the FLs is polyamide (i.e. Nylon) and not polycarbonate.
AFAIK it is reinforced with 60-70% glass fibre by weight.
A German Wikipedia comparison indicates that polyamide may have advantages in chemical and dimensional stability as against polycarbonate.
Zeiss obviously regard glass fibre reinforced polyamide to be the superior material and I was told by a dealer that production is more expensive than with die-cast alloys. However, customer acceptance is not high so we can expect the FL successors to have die-cast magnesium bodies like the Victory RFs.

John

@ tvc15_2000: those Leica are quite famous for their low-temperature usage, but that has nothing to do with the construction material, but with the lubrication (or the lack of it) of the focusser.

@ Purple Martin: so tell me what is the advantage of magnesium over plastics?

@ NDHunter: what makes you think Leica has a stronger construction?

@ Chosun Juan: Where do you get the idea that metals have better stiffness/resistence to bending stresses???

Companies build bikes, planes, skis and tennis rackets from carbon because it's stiff, strong, light, easy to build irregular shapes, more insensitive to temperature fluctuations than metals, etc.

I think that the main reason there isn't more advanced materials engineering in bino's, is because the audience is conservative, well illustrated by some of the comments in this topic.
It also doesn't help that the most popular bins these days is a Swarovision of about 830 grams, while they could easily build it to 750 like Zeiss and Leica without any durability penalty.

Temmie:

What makes you think the Zeiss FL has the strongest construction?
I do prefer magnesium frames, and I do feel they are stronger.

In my business I work with machines, and stresses and fatigue of construction materials is something I deal with every day.

Jerry

temmie said:

@ Chosun Juan: Where do you get the idea that metals have better stiffness/resistence to bending stresses???

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Temmie, I don't really get the gist of exactly what you're saying - "better" - than what? are you referring to?
I was referring to plastics, and of the same volume and form.
It's a function of the materials mechanical properties - Young's Modulus, Tensile Strength, Elongation, Density, etc.

Who knows the exact "receipe" Zeiss uses for the glass fibre reinforced polyamide ('ceptin' maybe the injuneers themselves!) - there's a bucket load of variables there - it obviously meets their spec for stiffness, strength, etc - whether it's up to /or exceeds magnesium's levels or not - there's a whole host of other reasons for jumping one way or the other as well.....

If you've ever seen Clarkson on "Top Gear", you'll know he regards the 'Vette's floppy plastic panels (light though they may be) in much the same vein as he does flappy paddle gearboxes! Honda has used CRFP (carbon fibre reinforced plastic) in its road race specials for decades, so there's no need for Zeiss or anyone else to stop there.....

Carbon fibre, Carbon-Carbon, Kevlar, etc, etc are different kettles of fish entirely......that was ma point......there's a bazillion possibilities in both construction and materials........(There's some Astroscope OTA's which are starting to be produced in CF sandwich composites - hold the mayo & I'll have mine without extra weight thanks!

temmie said:

I think that the main reason there isn't more advanced materials engineering in bino's, is because the audience is conservative, well illustrated by some of the comments in this topic.

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Can't say that I agree there...........folks just deal with and discuss what's available - pretty hard to see the nice birdies with a dream that doesn't exist......yet.....

Besides optic quality /price (or porro's for some!), the common theme around here is the number of curmudgeonly old codgers (and some just plain codgers) bemoaning the weight of back-breaking "Royal Animals" and binos in general......so the market demand is definitely there.....

If you offered a quality optic bino that was lighter /stronger /cheaper, folks would jump at it like lemmings off a cliff.....I don't think they'd be too worried if they didn't know the molecular structure of the materials involved!

Like most things, its weight of investment that usually determines technology and development......maybe when the titans of wall street are finished r**tin' the joint with their predilection for sexy cdo's, and get back to real businesses....I can finally have my carbon nanotube, printed flourite optics bino's! :cat:
and they'll be a helluva lot lighter than 750grms.....

Chosun :gh:

P.S. Jay, here's the link to the stress effects in prisms (although its more to do with fixing I suspect) - still grist for the mill...
http://www.birdforum.net/showthread.php?t=212971

There was a discussion last year on body materials in this thread (see comments 5 thru 7) :
http://www.birdforum.net/showthread.php?p=1784922#post1784922

Polycarb bodies/frames are injection molded and the magnesium & aluminum frames are die cast, all of which are fairly cheap and cost effective manufacturing processes. Carbon fiber or any other laminate process would be very labor intensive not to mention outrageously expensive.

Tom

NDhunter said:

Temmie:
What makes you think the Zeiss FL has the strongest construction?
I do prefer magnesium frames, and I do feel they are stronger.

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I didn't say that the Zeiss had the strongest.
I only said they are not necessarily weaker.
And you also know that the physical characteristics of the material itself do not tell the whole story, but also specific construction, connection points with the interior parts, the bridge, diameter of tubes, volume of used material,...

So for me, it's even untill someone proves that A or B is weaker/stronger.

lilcrazy2 said:

Carbon fiber or any other laminate process would be very labor intensive not to mention outrageously expensive.

Tom

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They can produce laminate carbon fiber bicycle frames for <200$ / piece in China, in the 100.000ths. So I suppose that producing some Binocular tubes wouldn't be a lot more complicated/expensive... B

Chosun Juan said:

Temmie, I don't really get the gist of exactly what you're saying - "better" - than what? are you referring to?
I was referring to plastics, and of the same volume and form.
It's a function of the materials mechanical properties - Young's Modulus, Tensile Strength, Elongation, Density, etc.

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I just cited you with that 'better', so you can explain me why you said that