Counterbalance pulley - confined 1

[jlawhorne]

I'm having an issue.

I have narrowed down my options to a pulley system. I have a 31x65 mirror that will be acting as a door to a recessed cabinet. This will be latched at the top with push button to release. Once released, it needs to lower gently. I will likely use ball bearing drawer slides to control the movement, but to keep it from lowering too fast and breaking the mirror, I need a means of counterbalance. The interior space is only 4" deep but 30" tall. I need it to lower the full 30 inches and the mirror weights 40lbs. I have been thinking of using spring tension with a two pulley system. I would need this to operate at each end of the 65" spread for balance.

Any advice would be great and any links to materials would be greatly appreciated.

 

[Lnewqban]

Counterbalance alone, like weight and pulleys, may not work for this application, since the mirror will be accelerating all the way down.
Perhaps you will need to engineer a simple friction mechanism that could have fine adjustment from outside.

"Where the spirit does not work with the hand, there is no art." - Leonardo da Vinci

 

[mfgenggear]

Yes like a small electric motor
And pulleys

 

[SwinnyGG]

Easiest way to do this would be to use a damper. McMaster has hundreds of sizes and configurations available.