Ideal bore and stroke?

[Nic]

Any opinions on ideal bore and stroke?

Typical bores seems to be 3/4, 7/8, 1 1/16, 1 1/4, 1 1/2. Anything larger, I don't think it'll fit in the pocket. I think 1 1/2 is already too big once you consider the fittings will add some overall width.

Stroke sizes, that are feasible seems to be 6", 7" and 8".

Overall cylinder length, open and closed. This varies with stroke.

 

[ydeardorff]

bore and stroke isnt all that you have to consider. Whats the flow rate of your pump, unloaded, and at full load. How does the ID of the lines affect it?

When you know what your pump and lines can do, then you can figure out what your rams can do.
For the system Ive designed, Im using high power short stroke actuator with a stroke doubler.

The transition of my actuator mount is 8" from open to close. So if your connecting the actuator directly to the canopy arms you would probably need an 8" stroke if your arms are like mine.

For instance a 1" bore x 8 inch stroke actuator contains just over 25 cubic inches of fluid volume.

So what is the pump rate of your pump? There are 231 cubic inches in a gallon.

Now its all about the math, and the mechanic advantage of the system against the lifting weight.

check flow rates here:
Hydraulic Flow Velocities Through Hose and Pipe Chart

 

[Nic]

Thanks for that info. I was really thinking basic functionality.

Is the 6" too short to open to canopy to get in/out?
Is the 8" too long, will it put the canopy over center and end up bending the cylinder rod?
Is 7" the magic number? Enough room to get in/out, without putting the canopy over center?

And the bore.... I already know a 1.5" bore is too wide, it doesn't fit in the pocket between the body and the dash. Is 3/4" too small? etc etc etc.

Just wondering if anyone had a magic number.

 

[ydeardorff]

Well I believe that 8" is the magic number.
The transition of the actuator arm mounting point on the canopy linkage is 8" from open to close. So you would need an 8" stroke maximum.

 

[islandman]

A simple modification I used to stop my canopy going over centre

 

[ydeardorff]

Nic,
Another thing I noticed with my rams...

If the cylinder is mounted at its base, the body of the ram will hit the surface of the pocket, though its stroke isnt finished. At that point the rams can get bent.

So plan for that. I think you were working on a way to mount the cylinders at their tops so the base of the cylinder could swing as the stroke completes. That design should prevent the rams from bending.