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Products => Test Equipment => Topic started by: Joe Geller on August 28, 2015, 11:35:49 pm

Title: hp 3456A Clear plastic layer partly de-laminated
Post by: Joe Geller on August 28, 2015, 11:35:49 pm
(http://www.gellerlabs.com/hp3456A/3456A_Delaminate.jpg)

I received a hp3456A with an impact to the left front corner (UPS shipping) that caused the clear plastic layer to partially come off.  The transparent layer extended very slightly past the edge of the metal front panel which might have made this one more likely to come apart.

The outer aluminum bezel bend might bend back without chipping the cream colored paint (later series 2943A, this one circa 1992 from component date codes).

Any thoughts on glues or other chemicals that might restore its original look?
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: xrunner on August 28, 2015, 11:43:11 pm
First question - is it sticky under the clear plastic, i.e. is there some sort of adhesive between the two parts now?
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: TheSteve on August 29, 2015, 12:04:51 am
This is just a total shot in the dark here but if you watch videos of people replacing the front glass on a smart phone where it needs to be glued to the LCD screen you see them use a clear liquid glue. You might want to look in to what they use, might do the trick here.
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: Joe Geller on August 29, 2015, 12:14:06 am
I do not feel stickiness to touch.  It is not smooth, but not sticky either ... it could be dried out.

There probably was an adhesive of some sort applied during manufacture?  Unless it was some kind of heat process?
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: SaabFAN on August 29, 2015, 12:24:25 am
Try this stuff: http://www.amazon.de/SHS-Kleber-Optisch-Transparent-Samsung/dp/B00GNW0M2U (http://www.amazon.de/SHS-Kleber-Optisch-Transparent-Samsung/dp/B00GNW0M2U)
It is used to glue Glasses of Smartphones and works great. UV-Light for cosmetic appliances (Finger-Nails) is enough to harden it.
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: xrunner on August 29, 2015, 12:43:33 am
Try this stuff: http://www.amazon.de/SHS-Kleber-Optisch-Transparent-Samsung/dp/B00GNW0M2U (http://www.amazon.de/SHS-Kleber-Optisch-Transparent-Samsung/dp/B00GNW0M2U)
It is used to glue Glasses of Smartphones and works great. UV-Light for cosmetic appliances (Finger-Nails) is enough to harden it.

Yea sounds good, but you prolly have one chance to try it, but what else can he do?  :-//
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: cncjerry on August 29, 2015, 06:24:36 am
I wonder if you heated it with a hot air gun if it would reactivate the sealant?  heat and press.
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: mos6502 on August 29, 2015, 07:44:45 am
How about a clothes iron, with a dish towel in between? Start with low heat  ;)
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: Joe Geller on August 29, 2015, 05:37:58 pm
I tried the dish towel and iron idea (brilliant!).  It was looking good, about 85% to 90% of the original look.  But, not as good as I hoped, so I raised the temperature just to where I noticed the very slightest shallow rolls in the clear window at the edge of melting I suppose.  Then, I backed it off a bit.  Several passes, and different heating times did not make much difference.

Then, after it cooled, I accidentally caught a corner with my hand and a large section just popped up again :(

More of the clear layer has released with the heat treatment.  Then, I pulled just a bit too much a few tiny paint patches have lifted now.

So, on the edge of a lost cause, I'm trying 3M 77 contact cement.  Covered the front surface and window with blue painters tape, sprayed on the contact cement, and it's out drying in the sun with a weight on top.  Maybe it will look passable until someday when I can pick up a late model DOA parts unit for something like $35 for a replacement front panel.

As an aside, some of those round calibration tags are agony to remove even with solvents, without scratching the front panel.  However, after a few seconds of steam iron, one lifted right off the short front panel calibration cover, intact!

(some sort of optical cement, as mentioned earlier, might have worked.  not sure how difficult it would have been to keep it from marking the window)
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: SeanB on August 30, 2015, 08:41:00 am
The UV cure resins are glass clear when cooled, they do work well provided you can get UV light to them to polymerise them. Failing a UV light noon day sun for an hour works almost as well. This is used to bond compound lenses together during manufacture. It never lets go on clean surfaces, and is available from a few places.
Title: Re: hp 3456A Clear plastic layer partly de-laminated
Post by: mos6502 on August 30, 2015, 09:59:20 am
Sorry it didn't work out.  :( Maybe it's not too late for the UV glue? You can get it real cheap on eBay:

UV glue:

http://www.ebay.com/itm/10ml-UV-glue-LOCA-Liquid-Optical-Clear-Adhesive-for-LCD-Separator-Screen-Repair-/252049610554?hash=item3aaf53d73a (http://www.ebay.com/itm/10ml-UV-glue-LOCA-Liquid-Optical-Clear-Adhesive-for-LCD-Separator-Screen-Repair-/252049610554?hash=item3aaf53d73a)

UV flashlight:

http://www.ebay.com/itm/Invisible-Marker-Blacklight-9LED-UV-Ultra-Violet-Flashlight-Torch-Good-Condition-/201399839768? (http://www.ebay.com/itm/Invisible-Marker-Blacklight-9LED-UV-Ultra-Violet-Flashlight-Torch-Good-Condition-/201399839768?)