krs
Member
On setting the depth of cut - does your machine have any sort of adjustable stop for the spindle? Like on a drill press? There should be one, I'd think, but if not that'd be something that the little machine shop guy has surely addressed.
Mini Milling Machine
- Thread starter schmeky
- Start date
- Status
schmeky
Member
krs said:
You answered correctly, I phrased the question improperly. What I meant to say is the degree or amount of cut. Example: Say I have an exsiting bore size of .600" and want to increase the bore size to .605". I center the boring bar, make slight contact with the boring bar cutter, then I would need to add .005" to the amount of cut. Can I measure this setting on the boring bar cutter with a standard micrometer?
Does this make sense?
krs
Member
does it make sense?
Go to the beginning. Are you using one of the adjustable boring heads that are widely available?
If so, you need to center the machine spindle over the bore to be enlarged first. You would get the spindle centered over the hole, set the boring head to it's own zero and put it into the spindle.
You must not move either the spindle or the table after having centered the spindle or you'll have to recenter it.
With the boring head in the spindle all tight and ready to go you should be able to lower your cutter, machine running, into the bore to be enlarged without the cutter making contact, or no more than a slight shaving contact. Now you would KNOW that everything is centered. This is more or less figurative but not a bad idea for a beginner to do - you need to know that when you go to cut you will be cutting the hole equally at all points of the circle. Anything else will result in an oblong hole.
Stop the machine and crank in your desired .005" on the boring head small micrometer setting device. They usually are pretty reliable. Set and lock the new cutting diameter and go for it.
Wait, you say you don't have a boring head? Go get one.
Go to the beginning. Are you using one of the adjustable boring heads that are widely available?
If so, you need to center the machine spindle over the bore to be enlarged first. You would get the spindle centered over the hole, set the boring head to it's own zero and put it into the spindle.
You must not move either the spindle or the table after having centered the spindle or you'll have to recenter it.
With the boring head in the spindle all tight and ready to go you should be able to lower your cutter, machine running, into the bore to be enlarged without the cutter making contact, or no more than a slight shaving contact. Now you would KNOW that everything is centered. This is more or less figurative but not a bad idea for a beginner to do - you need to know that when you go to cut you will be cutting the hole equally at all points of the circle. Anything else will result in an oblong hole.
Stop the machine and crank in your desired .005" on the boring head small micrometer setting device. They usually are pretty reliable. Set and lock the new cutting diameter and go for it.
Wait, you say you don't have a boring head? Go get one.
Definitely you should get hold of a wiggler for your toolbox, in the future lock your XY axis when drilling and don't move the table (if you can help it) until you are finished, this solves the problem. I have digital readouts on most of the mills I use these days and that also helps because I can easily travel back to the hole center without any tedious calculations and the problems associated with backlash.
schmeky
Member
krs said:
Thanx. That's what I was looking for.
MattTheHat
Member
To all those who posted in this thread: DAMN YOU ALL!!!!! 
My ISP probably thinks grizzly.com and all the other links posted belowng to some porn ring. Throughput to my home and office are WAY too high!
-Matt
My ISP probably thinks grizzly.com and all the other links posted belowng to some porn ring. Throughput to my home and office are WAY too high!
-Matt
krs
Member
Schmeky, it's occured to me that not all boring heads are the same, or rather that I don't know if they're all the same.
Point is that if I set mine to increse it's boring size by .005" it's actually moving the cutter out half of that amount or .0025". It's sets the radius and the diameter made will be twice the radius.
I should have thought to mention this caution in post #128.
schmeky
Member
krs said:
Thanx, however, I was aware the total bore increase is a result of 1/2 the bore cutter setting. But I'm confident I'll screw some things up soon.
BCRider
Member
You're WELCOME !
Yes it IS a sickness. The ability to create in metal will empower you with a thrill unlike anything else. It's almost like the feelings Dr Frankenstein felt when the lightning hit.... Scmecky, you got the right idea but trust me, when the cutter kisses the steel it's already cutting at least a thou or two. Opening up a hole from .600 to .605 would call for setting up the boring head and cutter on some scrap to size then swap the scrap and center the piece with the .600 and then bore it using the preset head.
On opening holes with more meat to play with I'd set the cutter to a light cut, like your kiss and maybe a thou more then cut a pass and measure it. Adjustments would be made using the boring head from there. On cuts that require I move the head more than about 10 to 15 thou I'd get close and then measure again and adjust for a smaller finish size cut based on what I find.
schmeky
Member
BC,
Thanx. I have CD that shows how to set the initial cut using a ZigZag rolling paper as a gauging device. Pretty neat. These papers are .001" thickness. I may give it a try.
Thanx. I have CD that shows how to set the initial cut using a ZigZag rolling paper as a gauging device. Pretty neat. These papers are .001" thickness. I may give it a try.
BCRider
Member
Common kitchen aluminium foil is also .001. That may save you if you don't smoke....
schmeky
Member
BCRider said:
Excellent tip, thank you. I don't roll my own anymore (or anything else for that matter), I'm in recovery, seriously.
- Status
Similar threads
- Locked
