G0704 BF20 Beltdrive questions

[fragger6662000]

Hi,

I am in the process of buying a BF20 machine and looks a great machine but it is only 2250 RPM, this is really too slow for me.

I own a converted X1 that i put a belt drive conversion on to increase the speed to 4000RPM which worked great. i am looking to do the same with this machine but concerned about the spindle bearing and how will the hold up to the increase in speed. i plan to increase it to 5-6K. so any experiences of doing this upgrade and it implications would be good to have.

PS i want to go faster as i mainly make small parts that need small corner radii and tend not to run steel but ally jobs.

[gd.marsh]

You'll find many threads on that type of machine if you'll browse around a little bit. Hoss provides a great deal of info on his thread .. including belt conversion.
Hoss's G0704

[hoss2006]

If you want to go 5000 or more, a bearing upgrade will most likely be needed.
The different versions of BF20's come with different makes, types and sizes of bearings.
A pair of Angular Contact bearings can get you safely to 8000 rpm or more for not much money,
but it could depending on the grade you choose.
ABEC3 (.0004 runout) would run less than $50, ABEC7 (.0002 runout) could be $2-300.
Hoss

[fragger6662000]

i was thinking angular contact route.

what speed have you run yours at?

[hoss2006]

i was thinking angular contact route.

what speed have you run yours at?

7200 rpm with the timing pulley belt drive version.
This shows the slower V-belt version.
[nomedia="http://www.youtube.com/watch?v=GsWYernevWA"]YouTube - G0704 Quill Belt Drive Complete.MP4[/nomedia]



Hoss