Boring Problem

[Bastelmike]

Okay, Nick

As I've written before, I have abandoned that idea already. The reason is that I can't get the boring bar out of the bores to measure the diameter. The Y travel isn't long enough and I can't remove the boring bar out of the mill because MT5 is larger than these holes.

So I will do it prob similar to Your proposal. Just one question, I'll do it in German, excuse me.
Würdest Du die zweite der fluchtenden Bohrung nach Kantentaster anfahren, oder besser mit einem Puppitast die erste Bohrung abfahren und danach dn Tisch positionieren?

Also I'm not sure whether I will use the horiz. mill because it lacks a DRO. We'll see

Mike

 

[MuellerNick]

Do it with the edge finder.
If you should be off by a few 1/100 mm, it won't hurt. Bearings do allow a certain amount of angular misalignment (magnitude of 0.1°, read the specs), do the math to see how much you can be off.


Nick

 

[MachineTom]

If you have a DRO on the BP, I would make the bearing boxes, and make two dowel holes, then make two in the base plate. Work carefull and you'll be within a thou. Bolts to hold it together.

 

[Marty Feldman]

Going to be tough getting the tabs to come out aligned when you attach them if you do the hole boring first. However, from your description of the part as welded steel, I would guess that the tabs are already in place, waiting for someone to come along to punch the holes in them. I think Tin's first post, above, is on the right track. Single pointing in a line-boring operation with the boring bar between centers will get you the end to end shaft alignment you want. The squareness of the shafts to the body of the part and the parallelism between the 2 shafts is a matter of careful setup.

 

[lensman57]

Okay, Nick

As I've written before, I have abandoned that idea already. The reason is that I can't get the boring bar out of the bores to measure the diameter. The Y travel isn't long enough and I can't remove the boring bar out of the mill because MT5 is larger than these holes.

So I will do it prob similar to Your proposal. Just one question, I'll do it in German, excuse me.
Würdest Du die zweite der fluchtenden Bohrung nach Kantentaster anfahren, oder besser mit einem Puppitast die erste Bohrung abfahren und danach dn Tisch positionieren?

Also I'm not sure whether I will use the horiz. mill because it lacks a DRO. We'll see

Mike

Hi,

Could your lathe take a Boring Head in the head stock spindle? If so mount the part on the cross slide - saddle, line it up with the axis, use a drill chuck in the head stock to drill the initial hole and then use the boring head to finish the job with great accuracy.
A long boring bar as being discussed is only necessary to bore long holes such as a cylinder, yours is just a bearing mount.

Regards,

A.G

 

[MachineTom]

On the line boring setups I've seen some have a special mic that slips over the cutter when mounted in the bar, and you set the standout of the cutter with it. Minus that, mic the distance from the bottom of the bar to the top of the cutting bit, subtract half the diameter of the bar from that number, the result will be the radius of the cut, then X2=Diameter of bore.