Edger Chuck Leaving Marks on A/R Coating

[jhegyi]

Occasionally I've noticed after edging a surfaced lens with an antireflective coating that the edger chuck has left an imprint on the back surface. I don't see it on most jobs, especially SV stock lenses with factory AR.

When I call the lab to tell them what happened and order a new lens they make it sound as if they have never heard of this before. Is this a defective AR application or is it the fault of my edger (Santinelli)? Should I be using some special pads on the back surface of the lens when edging? I don't use pads now because we don't have problems with slippage.

Thanks.

[Chris Ryser]

I don't use pads now because we don't have problems with slippage.

Above the AR coating layer you have the hydrophobic layer. If you have no slippage this could indicate that you are using enough pressure on the chuck and mark the hydrophobic coating.

[mdeimler]

Is it on material one more than another ? Transitions and hi index are more prone to these marks...I used a leap pad on the back on my old edger.

[braheem24]

it's your coating, get a better one ideally one with dip SRC as a base not spin.

[jhegyi]

Is it on material one more than another ? Transitions and hi index are more prone to these marks...I used a leap pad on the back on my old edger.

This was CR-39. Chris, is there a way of adjusting the chuck pressure on a Satanelli edger? (I ask without knowing if you are familiar with the brand).

[Slim]

you can adjust pressure in the service menu system.... not sure which one you have.

is the backside "chuck" in good repair? maybe a time for a new piece.

most ar jobs I go ahead and put a pad on the back.

[Chris Ryser]

This was CR-39. Chris, is there a way of adjusting the chuck pressure on a Satanelli edger? (I ask without knowing if you are familiar with the brand).

I have been around for a long time and the different names are familiar as well as the general techniques, but the individual models and machines of today are a foreign matter.

[davelp]

This is pretty common with the A/R stock lenses in my experience. ( btw a dip in hot water usually pops it back out ) I used a double pad ( front and back) as well as a protective "chip" on my Santinelli. I also noticed it was worse with Hoya's A/R than Essilor's ( when LC launched the Scotchguard coating about 10 years ago this problem gave me fits)

[Slim]

good point Dave. I thought is was marring the AR. it needs annealed, heat does it. I use the frame warmer but not all AR's can handle that. the only material it happens to me is the in house casted lenses (Q2100) but i never use that crap if i dont have to.

[Flux3r]

This was CR-39. Chris, is there a way of adjusting the chuck pressure on a Satanelli edger? (I ask without knowing if you are familiar with the brand).

i run a santinelli setup with the lex-1000 if you call them there is a way to adjust it, they'll walk you through it. i had the same issue a few months back and it turned out my predecessor had the chuck pressure up to 160!

[Tallboy]

God bless VSI.

[Speed]

Should I be using some special pads on the back surface of the lens when edging? I don't use pads now because we don't have problems with slippage.

Thanks.

Maybe you should try some pads and see if it solves your problem. There are many sources. Maybe the pads solve more than one problem.

[Flux3r]

i use the double block pad method and haven't had any problems since. couldn't hurt to try it, just match them up evenly.

[King of the Lab]

I used to use Blue Chip protector pads on both the outside and inside of the lens. This is really a typical occurrence with the Santinelli edger. Pressure can definitely be adjusted in the service menu.

[Tallboy]

Finally had this happen to me on my Santinelli. Its on Zeiss Individual Trivex Duravision platinum transitions. Arrrgh. I guess I will try the heat trick

I had seen "marks" before but they always cleaned off or dissapeared, these are subtle ghost images. I am probably doing the lenses over for a scratch the client found also, but these marks are most annoying on such a premium (read: EXPENSIVE) lens coating.

[lensmanmd]

Finally had this happen to me on my Santinelli. Its on Zeiss Individual Trivex Duravision platinum transitions. Arrrgh. I guess I will try the heat trick

I had seen "marks" before but they always cleaned off or dissapeared, these are subtle ghost images. I am probably doing the lenses over for a scratch the client found also, but these marks are most annoying on such a premium (read: EXPENSIVE) lens coating.

Sometimes they disappear on their own after an hour or so. Mostly, these are pressure related, meaning that the chuck pressure needs to be dialed back a smidge. As for the scratch, the DVP does not easily scratch, even with residual swarf being pushed around on the surfaces. Was the mark on the front or back surface?

[Stephen Santinelli]

We have been advising our customers to change the lens clamps more frequently as they tend to harden after 10 months. We are only advising increasing the chuck pressure to 160 (even 165) only if using the optional swivel lens clamp. The swivel lens clamp has replaceable rubber pads that can be replaced for $15. Of course all of this will not prevent slippage due to a worn rough wheel.

[Tallboy]

We have been advising our customers to change the lens clamps more frequently as they tend to harden after 10 months. We are only advising increasing the chuck pressure to 160 (even 165) only if using the optional swivel lens clamp. The swivel lens clamp has replaceable rubber pads that can be replaced for $15. Of course all of this will not prevent slippage due to a worn rough wheel.

I have thought about the clamp not being as soft as it used to be. I'm going to order one right now.

As for that job it has to be a problem with the AR because there are still visible marks from the factory markings you can still see the R and the line.