Help - Mortiser repair

[dragoneggs]

I just purchased a used Powermatic 719A mortiser in excellent condition except the gas strut powering the manual handle is 'out of gas'.

The OEM replacement part is about $146. I found an equivalent size strut on McMaster Carr for $22 plus shipping. What I don't know is what extension force to specify. The options range from 25lb to 250lb in 25lb increments.

Anyone have a clue what force I should specify?

 

[LeeG]

The cylinder is acting as a counter balance to the weight of the head. Put a scale on it and see how much it is pressing down, and get the next size higher.

 

[dragoneggs]

The cylinder is acting as a counter balance to the weight of the head. Put a scale on it and see how much it is pressing down, and get the next size higher.

That doesn't work in this case. I can stop and release the handle anywhere in the travel and the head does not move on the rack and pinion gears.

 

[dogdog]

The motor being the heaviest, maybe either take out the motor and weight it ? and go next size up ?

Or go to one of those sites that sell parts and look at the heaviest part it supports and total it up and guesstimate it ?

I saw the T but not the A on ereplacement site it does have shipping weight on the motor ... says 30LBS... add that and the next few heavier items, maybe ?

 

[Bogie1632]

Did the OEM cylinder have a part number and any other manufacturer information? Some have numbers that can be referenced to find their specifics through the manufacturer like pressure/weight rating, ends/connector type, length compressed/extended amongst other info. Many I've dealt with the part number is essentially a build summary.

Good luck.

V/R
Bogie

 

[Dumber than lumber]

With all the money you are saving just buy two or three.
Return the ones you don’t use.

 

[dragoneggs]

With all the money you are saving just buy two or three.
Return the ones you don’t use.

That's not a bad idea. I don't mind doing something like this from Home Depot where returns are easy but I guess McMaster Carr will take returns just the same. Just a little more effort on my part.