Pancake Cylinder Help

[pmangels17]

I am in the process of working on a new transmission design in Solidworks as an off-season project. I want to basically use the gears from an AndyMark Super Shifter. However, I want to use pancake air cylinders for the shifter instead of the standard Bimba cylinders that are on their site. I am, however, running into a problem. The AndyMark shifting block that the piston threads into is 1/4-28 female threaded, and the pancake cylinders that I have been able to find are 10-32 female threaded. Has anyone found a good solution to connect the pancake cylinder to the block? I would really love to avoid turning custom screws on out lathe, so any less machine intensive solution would be awesome.

What has your team tried to remedy this problem if you used pancake cylinders? What results have you had?

[Spen.M.P.]

Would something like this work? http://www.mcmaster.com/#92499A136 A standoff with two different sizes.

[AdamHeard]

We did this with the next size smaller pancake cylinder, which had an 8-32 Male thread and then used mcmaster 94165A423.

If you insist on keeping that cylinder size you can use mcmaster 90259A129 and retap the andymark block to 5/16-18.

If you also insist on using the female threaded cylinder, you can use a set screw/threaded rod (set screw is better due to the internal hex) to connect them.

[Mark Sheridan]

Lucky for you, West coast products has a solution.

https://store-b98ca.mybigcommerce.com/wcp-00131/

I think 3309 will be switching to these too.

[pmangels17]

Thanks for the speedy help guys, those are some pretty cool options. I had seen the McMaster standoff thread adapters, but unfortunately they didn't have the right size threads. The other block and the thread within a thread concepts are pretty cool, I'm gonna do more reading too.

Also, Adam, in stepping down a bore size, did you notice a difference in the force that the piston applied? Did it shift less smoothly?

[AdamHeard]

Originally Posted by pmangels17

Thanks for the speedy help guys, those are some pretty cool options. I had seen the McMaster standoff thread adapters, but unfortunately they didn't have the right size threads. The other block and the thread within a thread concepts are pretty cool, I'm gonna do more reading too.

Also, Adam, in stepping down a bore size, did you notice a difference in the force that the piston applied? Did it shift less smoothly?

It is less force, but we had no issue with that. We used 9/16" bore for two seasons (2010 and 2011) and they performed without issue.

[pmangels17]

Awesome, thanks. May I ask where you got your cylinders from? I would imagine the Bimba site but I was just wondering. McMaster only has the female threaded shaft from what I can find.

[AdamHeard]

Originally Posted by pmangels17

Awesome, thanks. May I ask where you got your cylinders from? I would imagine the Bimba site but I was just wondering. McMaster only has the female threaded shaft from what I can find.

I believe we ordered those directly from bimba.

[pmangels17]

Cool, thanks so much for your help. Did you adapt them to an AM transmission or did you use custom transmissions? If you used AM's, what else did you do to adapt them?

[AdamHeard]

Originally Posted by pmangels17

Cool, thanks so much for your help. Did you adapt them to an AM transmission or did you use custom transmissions? If you used AM's, what else did you do to adapt them?

When we did that in 2010 we used custom transmissions, but AndyMarks shift block.

You would have to modify or remake the mount plate, and probably change the length of the mounting standoffs.

[pmangels17]

Okay, I was going to re-do the mount plate anyway so it fit better into the custom gearbox plates. Thanks for all your help!