G-704 Spindle brake (2010 version

[Nahannidog]

Hello,
Hi to all, new to the forum....looks fantastic,

My G0704 benchtop mill from 2010 does NOT have a hole in the spindle nose to prevent spindle rotation when tightening the drawbar. I've been living with it, haven't used the mill alot, until recently. Occasionally. in desperation, I use a pair of channellock pliers to grasp the spindle nose. Also tried a rubber strap wrench (slips easily). I see that more recent version G0704 spindles have a hole for a pin. Looks like PM25 has ground flats on the nose.

Any suggestions how I might add a brake feature to the spindle?? I thought about drilling my own hole in the nose, but the spindle material is very hard, I can barely scratch it with a file. I'm sure it would destroy HSS drill bit Don't want to hand grind some flats as 1. it would be ugly, 2. grinding debris might go in bad places like bearings, 3. I would be really ugly.

I suppose dissassembling the spindle to remove the part 246V1 (diagram show version2, with factory hole, date 0811) would offer some more opportunities, but that seems like alot of work...but maybe you can convince me that's not such a difficult task

 

[markba633csi]

You might be able to drill a hole with a cobalt drill

 

[ozzie46]

Hello,
Hi to all, new to the forum....looks fantastic,

My G0704 benchtop mill from 2010 does NOT have a hole in the spindle nose to prevent spindle rotation when tightening the drawbar. I've been living with it, haven't used the mill alot, until recently. Occasionally. in desperation, I use a pair of channellock pliers to grasp the spindle nose. Also tried a rubber strap wrench (slips easily). I see that more recent version G0704 spindles have a hole for a pin. Looks like PM25 has ground flats on the nose.

Any suggestions how I might add a brake feature to the spindle?? I thought about drilling my own hole in the nose, but the spindle material is very hard, I can barely scratch it with a file. I'm sure it would destroy HSS drill bit Don't want to hand grind some flats as 1. it would be ugly, 2. grinding debris might go in bad places like bearings, 3. I would be really ugly.

I suppose dissassembling the spindle to remove the part 246V1 (diagram show version2, with factory hole, date 0811) would offer some more opportunities, but that seems like alot of work...View attachment 458909but maybe you can convince me that's not such a difficult task

The spindle (part #246V2 Should have a small blind hole in it to put a small Approx 1/4 in bar in to hold the spindle as you release the draw bar. The tool came with thew mill when it was new. If you acquired this used maybe it was lost.

If you look at the largest diameter at the the bottom of the drawing of the spindle you can just make out the small hole . I believe part # 292 is the drawing for the tool.

Ron

 

[Nahannidog]

If you look at the largest diameter at the the bottom of the drawing of the spindle you can just make out the small hole . I believe part # 292 is the drawing for the tool.

Thanks Ron. My spindle from 2010 version of G0704 does NOT have the small hole you are referring to. So there is no way to positively brake the spindle when attempting to torque the drawbrar to make the collet very tight. The 2023 exploded view shows p/n 246V2, and the corresponding parts list description calls this "Spindle V2.08.11 which I'm guessing means version 2 implement August 2011. So, I'm assuming my spindle is 246V1, without the brake hole.

My inquiry is if the forum members might have clever suggestions how to add some kind of feature to my Version1 spindle to function as a spindle brake. As mentioned, the spindle is very hard, don't think I can drill it, at least not while installed in the mill. I'm guessing that removal of the spindle (to make any modifications) is a huge task, and might compromise the runout of the reassembled spindle. Am I wrong?