Gripper pads or self adhesive?

[rsandr]

Hi,
I noticed in another thread somebody mentioned gripper pads.

Our rep visited this week and tried to convince us to stick these on all our laps then use non adhesive fining and polishing pads.

As i see it there is a small reduction in future processing costs and some ease of operation but i would be interested to hear from long term users before doing anything drastic.

What do you guys prefer?

Cheers
Rick

[Shutterbug]

We use gripper pads on all of our permanent laps with no noticible problems other than what was posted to the thread about scratches. They do seem to speed up the process and reduce costs. You'll need to compensate for the thickness of the two pads together (some of the old timers on this board don't like that aspect of it, but the newer computer programs should give acceptable results). Be sure to keep an eye on the wear at the edges of the gripper too. They'll cost you if you let them go too long :0). It defeats the purpose that way LOL. If you do not use them exclusively, you'll have to use different compensation amounts for the laps you do not use them on. There are programs available under 'downloads' that can do that for you.

shutterbug

[Jeff Trail]

Rick,

It depends on your volume and what type of things you are doing.. if you have a low volume say 20 or 40 jobs a day.. the time "saving" is not really a factor, if you are running a fairly low volume and a mix of weird stuff also it is not that good of a deal since you would be loading up laps that you may not use again for months... most often when I go into a lab as a consultant I look at a number of things as I listed, taking shutterbugs information as well, I might be one of those "old timers" he was talking about :) .. but the problem if you mix and match pad systems is you do not keep track of which tools (as in my lab I have better than 2300 laps no way am I trying to remember which needs compensated which does not ... so I would go with either or but not a mix.
Even though my production is a little higher I do go with a three pad system because I do so much weird stuff like biconvex and slabs plus cylinder and on and on and always running it past my generator limits and using the laps to rock in power at times.. I know guys, before you tell me "oh if you changed out the diamond wheel diameter you can increase your range", that is to big a pain in the butt :) so it was easier and more effective to use the regular pad system..
Also as shutterbug mentioned if you have multiple people running it through I know from experience that people tend to be lazy about changing out the gripper pad at times when they should..
I think it comes right down to personal prefrence, of course every supply rep will tell you "this is your best choice" (the product they are pushing) but if you are a smaller lab than have them give you a few samples to tinker with.. you can have a tighter control over your laps and tinker with base curves to use a certian range of laps most often and change out a few sets and run it for a few days on the samples.. than compare it ...not forgetting to reset your compensation for thickness :)
Than take your daily amount of production figure out the prices of doing it both ways... if you are smaller and are all over the place in laps chances are going with the three pad system would be more cost effective.. since you use a wide variety of laps but not as often.
Just my .02 worth...

Jeff "gee I hate to think I was one of those 'old timers' "Trail

[jofelk]

We run exclusively with the "gripper pad system".
Only a minor set-up in the software and everything is "fine"!
The time saved peeling off pads has provided a cost savings, and allowed more production.
When gripper pad shows wear it must be changed, you could start to see swirls if not.
Would never consider going back to old system.

[JRS]

Regardless of the volume, gripper systems remove potential injury causing elements to employees - no need for sharp objects to help peel the pad, no sandpapered fingers, and reduced carpal tunnel.
They are easy to use. Typically the only required change is to 'pad comp' in your software program. It is helpful - to maintain close curve control, that the curves sent to the generator match the curve on the lap. Which, depending on the initial comp built-in to the lap, may or may not need to be unrounded values.

[John R]

Re: Gripper pads or self adhesive?

rsandr said:
As i see it there is a small reduction in future processing costs and some ease of operation but i would be interested to hear from long term users before doing anything drastic.

What do you guys prefer?

Self Adhesive any day......
What the rep will have neglected to tell you is that you will have to replace the gripper pads every so often. Now with a few tools not much of a problem get a good range though and you are looking at a lot of work, also requires the tools to be cleaned at the same time. Which can be hard word as the polish gets real hard on the tools. This can be done as and when they wear out, but as you are just starting up you will have a lot that will wear out around the same time.....
I can tell you that them grippers stick a lot better and take a lot more getting off than any self Adhesive pad going.

[rsandr]

Self Adhesive any day......

Cheers John,
while i can see all the pro's i had talked myself out of them, i think ill give them the elbow at least for the time being.
Rick

[jofelk]

Grippers are changed when they wear but all laps are used at different rates and having to change them at the same time never became an issue. Changing one gripper pad instead of hundreds of self stick is by far easier. It pays to use this system if you are doing a full days work.

[JRS]

From John R

(begin quote)Self Adhesive any day......
...also requires the tools to be cleaned at the same time. Which can be hard word as the polish gets real hard on the tools. This can be done as and when they wear out, but as you are just starting up you will have a lot that will wear out around the same time.....
I can tell you that them grippers stick a lot better and take a lot more getting off than any self Adhesive pad going. (end quote)




If you let your laps get that dirty to begin with, and you put them up that way - not only are you asking for problems... but no system, gripper or otherwise, will work well for you.

[rsandr]

More about pads

Further to the pad discussion what to you experts think to one step fining pads, currently using a 1000grit at 1.5 min, 12 micron at 1.5 min, then a flocked polishing at 3 min all at 15 psi.
I only run CR39 at the moment.

If i change to one step there will be a time and cost saving in the fining procedure but is there likely to be a trade off elsewhere, ive run a few with some pads i was left as samples and all seems OK, are there some jobs such as transitions or hi index which would be better off with two step? Any opinions or experiences appreciated.

Regardless of the volume, gripper systems remove potential injury causing elements to employees - no need for sharp objects to help peel the pad, no sandpapered fingers, and reduced carpal tunnel.

JRS:
I find removal easy with no need for any sort of tool, i use plastic laps is this more of a problem with alu laps?

[Shutterbug]

rsander - The one steps work well with the normal Rx and save lots of time and expense. The Poly one steps are a bit less impressive. We find that 1 minute is enough at 18 lbs, and increasing the time gives worse results. You can fly through alot of work at 1 min per job :D Buy the pads that are comped for thickness so you won't have to recalculate everything.

Shutterbug

[Jeff Trail]

Rick,

You can tinker with the run time, I would NOT tinker to much with the pin pressure unless you are running spectralite or polys.. those times that the companies put out are based on (a lot of times) R&D at thier facilities.. which are not like yours:) ... I run 18lbs at 1 minute as well and 3.5 minutes on the polish... things like the water quality (heavy in deposits etc.,) will have an effect on your quality and run times..in the middle of summer because the pipes are shallow and in sand here in FL. our water from the tap can be luke warm, I'll run chiller on the water side as well as polish in the hottest time of the year because it generates to much heat...
Also the grit of pad will let you tinker with run times as well.. what I do is when I'm adjusting my cylinder machines with the axis blocks I'll block up a few plano lens (leaving them a little thick) than as I'm adjusting the pin placement and stroke I'll fine in that plano and tinker a bit..by leaving it thick I can go back and take a number of sweeps with the generator and able to run it again and again checking on the swirl patterns etc.,
I could actually run my lens as low as 45 seconds at 20 lbs. which if I get backed up I will do... all of our numbers as yours will most probably be different since from my experience all the cylinder machines run a little different.. and sometimes that gauge is NOT right on pressure so I also check that once in a while just to make sure the seals are ok that work the rocker arms.. most labs tend to just let this stuff ride but if you get in the habit of calibrating everything it will make your life a LOT easier and your breakage goes down to almost nill due to machinery.. one of my motto's in the lab is "you can't be better tech wise than your worst pc. of equipment" ..
Want to have a lab full of frustrated techs than let your upkeep of equipment get out of hand.. makes finding problems harder than it should be as well as have a lot of people pointing fingers at each other..I have seen labs fall a part to the point of actually getting into fist fights over this "blame game" and the cause of the problem was something as simple as running the blocker to hot
Get to know your equipment and make one person (or two) responsible for up keep, greasing, calibration & cleaning.. I keep a clip board by each pc. and it has what needs to be done daily, weeky etc., etc.. as well as a sheet with what has been done fixing it, when how and where the part came from..
Seems like a lot of work, but than again even with the crazy stuff I do (work wise) and volume my breakage runs 1 to 1.5% a month.. those numbers I just love :)

Jeff "it all fits together in the big picture" Trail

[rsandr]

I've started using QRS pads from DAC vision and life is much easier.
Jobs sail through much more quickly and a quick rinse after polishing keeps the laps clean.

Rick