Sounds like you're happy?
If so, that's great! I hope it works out for you. Please let us know how it goes. C5 ground ballscrews sound very decent, and I'm sure you told the salesperson that you wanted them for a mill, so no axial play. My guess is that those prices are around twice the cost, or a bit less than that, of the more inexpensive ballscrews from China, but they are for sure way way less than anything from Germany or Japan and the quality is probably fantastic. Probably a good choice if you don't want to mess around, or risk it. Did you figure out what you will do about driving the quill? Unfortunately, I can't be of much assistance there.
yes it was a case of me knowing what i needed and wanted before i could order so i downloaded the TBI catalog and studied what ball nut was designed for milling, as the part number said DFM series (designed for milling) it is a double nut which has a outer diameter smaller than others because of the double nut which i need to keep that size down otherwise the yoke that i have to make will become to large to fit in and the bed will hit it.
the only problem was if i wanted a left helix for the x axis they only do the DFM nut type in a 32mm ballscrews.
i have thought about the z axis and i am thinking at the moment how i can engage and disengage quill from manual to cnc have got any thoughts on that.
To answer your question if you have a servo that is capable of 3000 RPM, then with 2:1 gear reduction, your ballscrew would spin at 1500 RPM at max speed. With a 5mm lead, 1500 (Revolutions / minute) x (5mm / revolution)
= (1500 x 5) (revolutions x mm) / (minutes x revolutions), the revolutions cancel out and you get 7500 mm / min.
7500 (mm / min) / 25.4 (mm / inch) = 295 inches / min max speed.
If it were me I'd go with the 2:1 gear reduction on those. That will give you a bit better acceleration potential and you don't need a top speed over 295 IPM for rapids on a mill. You could probably run that at 0.3G or more linear acceleration just based on continuous torque and have more cutting force than your spindle could handle. Although you may tone it done from what it can actually do to be within your comfort level and what your mill can handle, as Jim has said in his posts.
yes i think the 2.1 ratio will be my choice, the speed will be faster enough for what i will need considering a cnc knee mill is not ideal and is never going to be able to run speed like a linear rails but i had the mill and decided it won't be perfect but it will be very helpful for me.
Have you sourced your belts and pulleys yet? Could that not effect your end machining?
i have not sourced them yet but if anyone knows a site to get them from please let me know,the x axis has the power feed mounted and there is plenty of shaft sticking out to mount drives, i am thinking of milling up a complete new end housing with the same bearing mounts as the the old end plate but will also carry the drive motor and be able to fix a cover,the x axis will be able to be done by removing the dial wheel because i don't need it as it has a dro
Probably the first thing you should do when you get your ballscrews is to get them in the bearings and give them a spin to make sure that they are not bent
thanks for that info i sure will.
Also, you should make a post here to give us a review of your experience with the TBI ballscrews.
i will put photos up when i get them and of the installation as well i got the ground screws because i thought it would give less noise in operation
When you place your order you can specify in which orientation you would like the nut to be. If you don't specify and it comes the opposite way, then you have to take the nut off and flip it around. There is always a risk of loosing balls when you do this, and it's best to simply tell them the orientation that you want so you don't have to mess around with this if that's at all possible.