Glueing / securing an LCD display to PCB

[Djarn]

I have a LCD / PCB that came off a rowing machine.

The LCD has come off the PCB, and needs to be reset, however I'm not sure what to do it with?

What happens ( if you look at photo's, he lcd sits on the pcb "sensors", I can get it working if I manually press the lcd onto the pcb, however it obviously does not stick, what is used for this?

Thanks for any help

 

[davelectronic]

LCD fixture

Hi Djarn.
I would say positive pressure from the enclosure to contact the pcb pads, bonding is fairly permanent, but if i bonded it i would use two part epoxy, but add positive pressure during reassembly, and clean the contact surface with isopophyl alcohol on the LCD and the pcb, but remember epoxy bonding is permanent.

You could try a silcon or rubber gasket, for the pressure on reassembly, but its finding one of the correct size, and if the units case will be secure, ie no movement in use.
Dave.

 

[Resqueline]

It's supposed to be fixed by mechanical means only (pressure). Isopropyl alcohol is beneficial to use before reassembly.
But by all means don't try to bond or glue it to the PCB, that'll ruin any chances of it ever working again.
Any sticking only developes after a number of years of being pressed together.
What was the problem initially if I may ask?

 

[davelectronic]

If bonded, and i am not sure its the best idea, i would use it in tactical areas with positive pressure until setting has cured,not on the pads contact surface, but gluing bonding as i said is a single fix, if it worked, i would go the gasket route first.
Dave.

 

[Djarn]

The reason it wasn't working is because it was transported by ship, however batteries were left in, batteries leaked, when we got around to fixing it all had to be cleaned up, it's working now if you press the two parts together.

Where would I take it to be reset? I am in Cyprus but will be in UK in 2 weeks.

 

[davelectronic]

Led display

I would not have any idea in cyprus, but there are repair services in the uk. A google on the products specifications would throw up some good services, if its a good quality piece of kit, then its worth doing properly. who disasembled the unit ? as repair is the reverse of undoing the unit, not to difficult i would not think. After the battery clean up, you just need to make sure its all carefully lined up on reasembly. Done carefully you should be able to put it together. Dave.

 

[davenn]

Please DONT put any sort of glue anywhere near those rubber pads!!!
else it will NEVER work again

Those rubber strip pads are conductive and bring the PCB contacts into connection with the
contacts on the glass surface of the LCD panel.
By all means clean those rubber strips along both surfaces with Iso. alcohol etc but look at how the pressure of the panel and pcb is achieved and see if there are ways to improve that
to ensure a firm contact between LDC and rubber strip and then to the pcb.

Dave

 

[davelectronic]

LCD

Hi again. Please dont think the use of expoxy on my surgestion was reckless, if used properly and in a tactical way this would still work, the contact rubber pad suface is conductive, so epoxy there is totaly undesirable, and a no no. but it looks as if ive told you to do something totally destructive, not my intentions. Epoxy in your repair, and as great care is needed and is probably not the best idea. re assembly of the unit will create the pressure needed, and correct function should be restored.

 

[davelectronic]

LCD display

So in conclusion the best way forward is probably a repair out let service. As a machine like this would not be to cheap to replace. My surgestions did not take into account others confidence and experiance, so on my part apology's. My intensions paint a picture as if i surgest you be wreckless with powerfull bonding agents, that was never my intentions, so i wish you the best out come with your lcd repair, and with luck your machine should be restored to full working order.
Dave.