nolabama

I will send you some links later for where to get those ball screw linear actuators. IMHO a cylinder puts out more force than engineers say they do, having said that they seem to grossly undersize the actuator. Those ball screws are problamtic. I would recomend designing this without pulleys if at all possible. Encoder problems as stated, maitanence issues. Their is an air powered linear actuator that uses internal cables, but i dont think it moves very slow at all. And it needs to be as long as it moves similar to a hydraulic cylinder. A servo cylinder is gonna cost a fortune. The only app I have found foe them is areospace and aircraft, really pricy stuff.

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“Dammit, Smithers, this isn’t rocket science, it’s brain surgery!”

nolabama

we use these and IMHO they are junk
http://www.duffnorton.com/

re reading all the posts and i was a little confused - thinking you needed a servocylinder not a servo motor -sorry -

so your gonna do the rotational to linear conversion yourself lol

good luck with your machine

__________________
“Dammit, Smithers, this isn’t rocket science, it’s brain surgery!”

wildleg

what's the application. sounds like you are trying to reinvent the wheel

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mutabi

Thanks guys for all of your input. joethemechanic answered my question as to how to calculate the torque necessary to move the piece. It turned out to be super simple but for some reason I was thinking it was more complicated.

I wish I could post pics of the actual machine but I can't. Trade Secrets etc etc.

As for reinventing the wheel....well possibly. We are looking to innovate. To create the only machine of its kind in the world. Its a challenge but I am learning a lot. What we are trying, may and may not work. BUT if it does work, there is a lot to be gained from it.

Thanks also to the other suggestions with the rack and pinion and ball/screw type mechanisms. They are definitely something I will be looking into, to see if there is any way they can be incorporated into our machine design.

As always +1 to the members of electriciantalk.com!

John Valdes

Why not ask someone who reps servo manufacturers? They do design work. If they smell business I bet they come out and help you. For free. Tell them you have some projects coming up and need some help.
Baldor builds servos and has tremendous helpful people on board. As a matter of fact, there home office is in Fort Smith Arkansas. Go to their web site and find a "authorized service center" Give them a call and see if someone is interested in coming out for a look. You might even get a free lunch out of it along with some help.

nolabama

are you a google plusser ?

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“Dammit, Smithers, this isn’t rocket science, it’s brain surgery!”

joethemechanic

WTF is that? "Google plusser"???? Not sure I would want to be known as a "google plusser"

nolabama

its that or circle jerk - whichever you prefer - its googles version of face book

the +1 is the google version of the "like" hand thing since he +1ed us i figure he is a geek on the google like me

__________________
“Dammit, Smithers, this isn’t rocket science, it’s brain surgery!”

joethemechanic

Well, maybe better to be a Google Plusser that a Foamer

mutabi

Haha Yes I am a Google Plusser. I have no idea what a foamer is??