Rimless frames and base curves...

[drk]

On a few rimless frame styles, we've noted that the finished product may have more "temple spread" than the demo frame and lens...

...because the base curve is flatter on the Rx pair.

In some cases, we can compensate, but in some we cannot....

I am currently reordering a pair with the same BC as the demo lens, since it fits too loosely ("occipital fit"-type frame). Optics be danged.

What are the thoughts on this seemingly common scenario? How do we screen for this in advance?

[Chris Ryser]

What are the thoughts on this seemingly common scenario? How do we screen for this in advance?

Very simple..........How about getting some pliers and do a proper adjustment?

[CME4SPECS]

Your lab is probably just drilling the holes, then mounting the lenses. They are not "bench" aligning them. Just angle the endpieces inward. It's not to difficult.

[victor]

Also, put some limits on your Rx range for rimless eyewear. -6.00 or +6.00 will usually look pretty ugly and have adjustment issues on rimless eyewear.

[drk]

Thanks for the replies!

I CAN'T adjust "temple splay" (what is the correct terminology, anyway?) on these endpieces...they are solid, unbendable, thick, blocky, metal.

Waaahhh.

[HarryChiling]

You may need to unmount (he he unmount) the temples and adjust. The thick ones are tougher, but it can be done.

[Andrew Weiss]

drk,

Question is, why are you carrying this rimless style if it's such a bear to adjust? ;)

[apaul]

[quote=drk;183771]Thanks for the replies!

I CAN'T adjust "temple splay" (what is the correct terminology, anyway?) on these endpieces...they are solid, unbendable, thick, blocky, metal.


Dont you just love these designers!!

Alan

[TLG]

Purchasing frames can be a humbling task. We fall in love with style, materials and features but sometimes don't realize a frames limits until we dispense one. A primary consideration in every frame you buy must be its adjustability - if you can't adjust it, you must get rid of it/them. If the endpieces are "solid, unbendable, thick, blocky, metal" that would be a sign to me of poor quality.

It sounds to me like you are talking about a nylor-type rimless and I have to admit, I have fit them since about 1980 (anyone remember 'next to nothing means something'?) and don't remember ever having one I couldn't adjust.

Good luck!

[Chris Ryser]

If the endpieces are "solid, unbendable, thick, blocky, metal" that would be a sign to me of poor quality.

correction.....................solid, blocky ect is not poor quality but actually might be better quality...............I would rather say that they are a not a good design/

[DragonLensmanWV]

Thanks for the replies!

I CAN'T adjust "temple splay" (what is the correct terminology, anyway?) on these endpieces...they are solid, unbendable, thick, blocky, metal.

Waaahhh.

That's what two pair of Numont pliers are for. Grab front, grab side, bend.

[gemstone]

You may need to unmount (he he unmount) the temples and adjust. The thick ones are tougher, but it can be done.

Some of them fit right in to notches on the lens. You'd have to bend the temple behind the hinge. Looks like crap. For some that base curve is the only way, limiting tha power.

[drk]

You opticians are a tough lot...my arm strength isn't what your's must be...

This is a "cool" looking rimless frame from Morel...an "Oga" style.

And you're right: I bought it based on "wow" not "how?:o ".

[DragonLensmanWV]

You might want to call up the lab manager and request that they "square up" your frames before they send them out.

[Fezz]

You opticians are a tough lot...my arm strength isn't what your's must be...

That's the problem Doc.


We Opticians just bite down on these tough ones and naw at 'em with our teeth. The jaw bone has lots of strength and great leverage.



:cheers: :cheers: :cheers:

[TLG]

correction...

With all due respect, I stand by my assertion...

-Tony

[Audiyoda]

Wait a minute - why didn't the lab drill them properly? With todays multi-axis CNC drills, the correct angle of the drill holes should have been a no-brainer to compensate for the lens' FBC. I've never had that problem from my lab - then again they have a CNC drill that I believe can make breakfast in the morning if you show it where the butter and egs are.

[gemstone]

Wait a minute - why didn't the lab drill them properly? With todays multi-axis CNC drills, the correct angle of the drill holes should have been a no-brainer to compensate for the lens' FBC. I've never had that problem from my lab - then again they have a CNC drill that I believe can make breakfast in the morning if you show it where the butter and egs are.

That does not work with some designs.

[Audiyoda]

That does not work with some designs.

I haven't found that design then - and I've seen many, many drill mounts beyond the popular compression mounts. I think if labs took the time to evaluate the frame they have in their hands - problems like this wouldn't happen. I've seen lenses notched, etched, beveled, and routed to accomodate the unique style of the frame as it relates to the lens FBC.

[Jedi]

I find that anytime an RX frame has a steeper base curve I will clock the cull lens, assess whether the patient RX is suitable for that frame and order lenses on that base curve. The problem with adjusting some of theses frame, is if you are applying a lot of force with your plier it can be very easy to mar the finish and damage the frame. Best to start with the proper BC, if it's not suitable for the RX, find anther frame.

[gemstone]

I think if labs took the time to evaluate the frame they have in their hands - problems like this wouldn't happen. I've seen lenses notched, etched, beveled, and routed to accomodate the unique style of the frame as it relates to the lens FBC.

You are absolutely correct. I would also add that frame purchasers should have the experience to do the same and not buy these **** poor designs just because they are sharp looking. That would save everyone a lot of trouble. Not to be argumentative, I've seen a few myself. Most are good. Some are not.

[Jedi]

While frame purchasers should be aware of potential lens complications, ultimately it is up to the Optician and their knowledge to ensure a job is done correctly, even if it means saying no to a particular type of frame. I have dealt with many companies that include RX limits to their frames as well as other lens processing information, maybe more need to follow suit, or hire reps more optically knowledgeable.

[Jacqui]

or hire reps more optically knowledgeable.

This would help everybody :D

[Jedi]

This would help everybody :D

We can always dream can't we.;)

[MarcE]

DrK,
Damn, these guys are rough. I am wearing the frame you speak of right now. It's my favorite. It is outstanding quality. One of the most stable and rigid drill mounts out there. So yes, it is hard to adjust. I have drilled it myself in a 0.5 BC up to a 6.25 BC. The lens maybe wasn't drilled at the correct angle. But here is the real answer:

TRIVEX.

Then you can grab that thing with channel-locks on one end and Vise-grips on the other and adjust without fear of breaking the lens. A few gouges in the frame are perfectly normal:D