Drill a hole at the bottom of a V-notch...

[higgite]

Hi Tom

I actually thought of something similar by using a "largish" 90 degree cutter but wasn't sure if "eyeballing for daylight" was very accurate.

Not "daylight", backlight. If the two Vs are both 90 degrees, you can see when they align. If you have a large enough 90 degree countersink, that would work, too.

Tom

 

[Cadillac]

Here’s a way to accurately find the angle of the part and get a hole in the center of the crotch. Align the part to the axis with a indicator. Cut your slot. Then if you have a precise 45’ stand it up in your slot so it’s flat on the top and run a indicator on the flat till your readings match. Now your angle is set. Take a dowel and indicate that to find center of the slot. Here’s a pic of what I mean if not clear. That should get you what you want.

 

[jmarkwolf]

Stick something under the part so you don't drill into your vice.

Absolutely!

 

[jmarkwolf]

Here’s a way to accurately find the angle of the part and get a hole in the center of the crotch. Align the part to the axis with a indicator. Cut your slot. Then if you have a precise 45’ stand it up in your slot so it’s flat on the top and run a indicator on the flat till your readings match. Now your angle is set. Take a dowel and indicate that to find center of the slot. Here’s a pic of what I mean if not clear. That should get you what you want.
View attachment 313788View attachment 313789

Sorry Cadillac, I simply can't see what you're doing there.

 

[jmarkwolf]

OK, I think I've got it sorted with all of your help. See pic below.

If you haven't guessed, I'm revisiting my tilting fixture plate that I wasn't pleased with so far. I had bolted the plate to a side of the V-notch, but a gap had opened up. Someone had suggested locating the screws so that they would draw the plate into the crotch. I liked the idea but wasn't sure how to go about setting that up, so the project languished.

With all of your suggestions I think I know how to proceed.

1. Turn the round stock in the vise so that the V-notch is perfectly about the vertical axis. like Cadillac was suggesting.
2. Align the spindle by finding the edges of the V-notch like GL was suggesting. I'll use an edge finder and the DRO center function.
3. Drill the holes.

Thanks everybody.

The next question will be how to drill into the corner of the plate. But that's for tomorrow.

 

[jmarkwolf]

Update:

I took a deep breath, and proceeded with re-working the mini-pallet (tilting fixture plate) with all of your help.

The triangle trick from Cadillac worked great. Even with the sharp corners on the triangles it fit my V-notch perfectly. I tried some rectangular magnets to hold the triangle in place, but the spring tension on the indicator would cause it to break free when on the ends of the triangle. I tried some round magnets and they worked much better. I just carefully turned the round stock until the indicator read zero the entire length of the triangle, then tightened the vise.

Then I used an edge finder and my DRO's "Half" function and it worked famously. I double checked by using a small center drill as a pointer and running it down the length of the V-notch and it was dead on the entire length.

I was then confident enough to do the spot faces and center drills.

Next I'll drill the five new 3/8 in holes but my stubby drill bits have seen better days, so I'll get some new ones tomorrow. I'm a little concerned about drilling through the round stock because the outer diameter of the drill bit will break through the back side of the round stock before the point will, so I may wreck some new drill bits.

If all goes well, nobody will ever see the four old holes on the flat of the notch. I won't say anything if you wont.

See pics below.

 

[GL]

Excellent, take a few ideas from to group and make it happen like you envisioned. This is a cool site - no "duhs" or crap, just lets figure it our with the collective experience. Cool trick Cadillac, need to gets some angle blocks, been looking at them, but this may push it over the edge.

 

[homebrewed]

My angle vise has a scale on it to indicate the tilt angle, and that's been good enough for many projects. But for jobs that require an accurate angle I install an angle block in the vise, adjusting its angle until an indicator doesn't move as it is swept across the top of the block. So the technique is useful for things other than setting up a vee, and is part of an experienced machinist's bag of tricks.

It also isn't too difficult to make your own angle blocks for specific requirements, like cutting gibs, grinder guides for making HSS bits etc.