Homann Designs TM20LV (BF20,G0704) conversion
This is the start of a journey. I've had a Taig CNC mill for over 10 years now and it is a fabulous machine. I was after a larger machine and the Grizzley G0704, BF20 or Sieg X3 seemed popular choices.
If all turns out well I'll should be able to provide a nice controller kit for this type and size machine.
The G0704 is not available in Australia. The X3, is as are a number of BF20 style machines. In the end, I chose a TM20VL from Titan Machinery. It looks similar to the G0704 and the BF20L but does have some differences. I could have got a BF20L for less, but I was not sure of the quality. Also I wanted an R8 spindle so I could use TTS tooling.
I'm planning to do the conversion following the CNC Conversion DVD by Hoss. Obviously it depends on how closethe machine is to the G0704.
The TM20VL has the following Specifications:
- Spindle taper R8
- Spindle travel 50mm
- Quill diameter 60mm
- Table size 700mm x 180mm
- Table travel (longitudinal) 550mm
- Table travel (cross) 180mm
- Max. dist. spindle to table 360mm
- Max. dist. spindle to column 185mm
- Machine depth 580mm (to front handle)
- Machine height 930mm(head fully extended)
- Machine height incl stand 1730mm
- Head tilt 90ยบ both ways
- T-slots 3 slots, 10mm studs
- Range of speeds 0-2500 RPM
- Motor 800W BRUSHLESS DC, single- 240v single -phase
1 Attachment(s)
Need help on X-axis ballnut.
So, now I need some help on how to do the X-axis ball nut.
I plan to make new end plates for the table which will hold the ball-screw end mounts. At this stage I'm planning to use 1605 ballscrews and use the FK12 and FF12 style ball screw supports.
FK12 16mm BALLSCREW END SUPPORT BEARING BALL SCREW CNC | eBay
I also plan to use a FK12 on the Y-axis as well.
The ball nut mount is more problematic. The ball nut mounts are 25mm apart so I could use them . The centreline of the lead-screw is 15 mm above the base and this is where the problem is going to be I fear.
I have a Taig CNC mill, and the TM20VL saddle will fit if machining is necessary.
The dimension of the Ballnut from CNCShop is attached.
The diameter of the ballnut is 28mm excluding the mounting flange. This gives me a 1mm clearance to the 15mm centreline. I could mill a clearance slot in the saddle for the flange. I would then have to mill the top of the flange so that it does not interfere with the bottom of the table.
I could also mill the top and bottom of the flange which is my preferred plan at this moment.
Any ideas welcome.
Cheers,
Peter.