[bill south]

Nic;
I'm interested in the pneumatic counterbalance concept but know very little about it. I've rebuilding an old lathemaster rf45 and installing linear rails. I'm thinking that head travel (falling) will be a problem when powered down. I really don't want to use gas struts if there is a better option! By chance, do you have a design you can share or point me to?
Thanks for sharing! There is a lot of helpful info in this thread especially about using push on couplings. I never had much luck with them but it appears that it's about time to revisit the subject!
Bill

[NIC 77]

Nic;
I'm interested in the pneumatic counterbalance concept but know very little about it. I've rebuilding an old lathemaster rf45 and installing linear rails. I'm thinking that head travel (falling) will be a problem when powered down. I really don't want to use gas struts if there is a better option! By chance, do you have a design you can share or point me to?
Thanks for sharing! There is a lot of helpful info in this thread especially about using push on couplings. I never had much luck with them but it appears that it's about time to revisit the subject!
Bill

Thanks for your encouragement Bill. I'm not familiar with the lathemaster, although I did just google it. Looks like a mini mill. I am also learning that there is a better option than gas struts. I would say for a design, one 32mm bore gas strut on either side of the mill (but you could probably get away with just one) connected to a small air reservoir. You'll probably have to have your strut(s) mounted at an angle with a mini mill configuration, so that will need to be factored into the calculations to find the component of force that is upwards and how much that changes at the top and bottom of the stroke. Definitely you'll want swivel connectors or ball joints at the ends of the pneumatic cylinders.

Are you going to mount a more powerful motor on your mill? Well, the beauty of using pneumatic cylinders is that you can adjust the pressure later on.

I can certainly let you know how it goes with my progress, but it will be a long time I think before this is all up and running. Probably a month to ship things to me, I just want to get these parts ordered so I can focus on building and have them when I am ready for them.

If you can make a list of all the parts you need, you can ask for a custom order on aliexpress, probably the least expensive but it will take a long time to get to you, or you could get parts from somewhere like automation direct, as you are in the states, this might be easiest.

The first step is to figure out how much Z axis movement you have, and to determine an approximate weight of the Z. I don't mind in the least if you piggyback on this thread with questions or comments about your own similar project, in fact I encourage it. If you'd like to make this thread a shared thread on the subject, no problems.

Yes, there is alot of helpful info here, thanks again to vegipete, JimDawson, and Ger21, and thanks again for the encouragement.