LINEAR RAILS ON PRT 96

[gundog]

Very nice upgrade.

[ljdm]

Did you modify the Z also?

[joe_culpepper]

The z axis is a Parker assembly with lead screw and linear rail and bearings. All of the parts except the metal came off E-bay.

[jon]

Joe, your work has inspired me to go ahead and rethink the BWC route. I went on iges' website and started looking at rail and cars. Are those cars you used filled with ball bearings, or are they the low friction plastic type?

[joe_culpepper]

They are the ball bearing type.
Go on E-BAY and search on this item number (110298124672)and you will see the type that I used.

[jon]

Thank you Joe. Has anyone considered the solid plastic types? IGES website says that the rails will not need lubrication, and that they perform like the bearing systems but with no noise and cheaper!

[gordon]

We have played around with the IGUS plastic bearings in several styles and types and after testing them were extremely disappointed in the amount of friction and amount of initial force required to get them moving. For a lighter weight app I could see them being very good, low maintenance and cost effective.

[jon]

thank you Gordon! I will not be investigating the plastic route further.

[myxpykalix]

Jon
as a further FYI the legacy ornamental mill used the plastic bearings on a lightweight manual cnc type machine and we saw the bearings for mid range users would wear out constantly and slop built into the system due to the friction factor made the system as it was unusable for a cnc operation and they went and designed a whole new machine for cnc which is about 3 times the cost of a shopbot and worth less then half in my opinion.

[carlcnc]

I have built or re-manned lots of machines,
tried the IGUS type stuff, Thomson bushings on roundrails, as well as vee-rollers.
If you want to build your own machine and do production [aka make money] with it profile rails are the only way to go.