V-block Question.

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Lood

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Yesterday, I decided to make my own v-block. Items like these are rather hard to find locally, so I took a 2 3/4" (68mm) shaft from a KSB centrifugal pump, cut off the required length, faced both ends in the lathe and then started squaring it in the mill. The final dimensions of the finished block is going to be about 2" wide x 2" high x 2 3/4" long. I've still got some way to go, but I would like some opinions on the V, please.

1. What will be the best way to cut the V? Do I tilt the block 45 deg in the vice or do tilt the head of my mill 45 deg and keep the block flat in the vice?
2. How deep do I mill the V, or do I mill it up to a specific width on the open side?
3. Can I also mill another V on one of the ends of the same block to accommodate smaller workpieces?

Any other opinions and advice would be much appreciated.
 
It seems very handy to hold round workpieces, like shafts, disks, etc. in the milling vice and it's quite a fun project, which is also improving my skills on the milling machine.
 
it gives you a way to hold a round part for various things. such as milling 2 parallel sides or a slot. it is also good for checking to see if 2 flats on a round part are centered on the round part.
 
1. Either way will work just fine, it depends on which way is easier for you to set up.
2. I don't think there is a "specific width" you can make the V as wide and deep as you require.
3. yes as long as you leave enough steel in the middle so the block won't deform under clamping pressure.
Please post some pictures!
 
Lood said:
It seems very handy to hold round workpieces, like shafts, disks, etc. in the milling vice and it's quite a fun project, which is also improving my skills on the milling machine.
Click to expand...



Billh50 said:
it gives you a way to hold a round part for various things. such as milling 2 parallel sides or a slot. it is also good for checking to see if 2 flats on a round part are centered on the round part.
Click to expand...

I'm pretty sure I worded my question wrong. What I meant to ask was, what do you intend to use this v-block for? How precise do you need it to be? Do you plan on surface grinding it, or just leaving it milled? The reason I'm asking is that v-blocks can be a bit tricky to make. A true precision v-block has the v cut exactly in the center of the block If not, it can cause a lot of headaches when your using it. For example, when trying to cut symmetrical flats on a round shaft. It's to hard for me to explain how I would measure the v to make the block symmetrical, but I an throw together a quick cad drawing that would explain it, if your interested.

Btw, cool project. I'm interested in seeing how it turns out
 
Damn, Tapatalk won't let me edit my post..

My post should have said, the v needs to be exactly in the center of the block, otherwise it can cause a lot of headache when trying to use it.
 
And rather than worrying about milling the vee exactly in the middle, ( if no particular block width is critical), then after measuring as in jasnook's diagram, you could trim from the longer outside face. And not have to move the vee!
Greg
 
Thanks a lot guys, your advice is really useful. Only after my initial post did I realize that the most critical part of this project will be to get the V exactly lined up with the sides of the block. If it is even the slightest misaligned, the block will be useless.
When I'm ready to cut the V, I will again gauge the side of the block from the spindle, to be perfectly lined up along the axis along which I'll be cutting and then hope for the best. The diagram above is real handy and gives very nice perspective on how to measure the V afterwards.
I really like the idea of milling the V first and then square the block from there. This should be much easier and if I have to make another V-block, I will certainly try it this way.

Below is a picture of the squaring process. Seeing that I did not have a V-block with which to hold the round workpiece, I tapped it while tightening it in the vice, to make sure that it sits nice and flat on the bottom. I then milled off only 2.5mm to get one flat side, before turning it over. Took off another 2.5mm on this side to get two opposing flat sides to be able to hold it properly in the vice. Low and behold, when I measured these two flat sides to faced ends with a machinist square, they were just that - square!

In picture, I'm busy milling the third flat side. I have to remove 10mm from each side, which will leave me with a 48mm x 48mm (2" x 2") square. Besides this being a very interesting learning curve for me, I'm also getting to know my milling machine and I'm sort getting the feel for it - if you know what i mean.

V Block.JPG
 
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