My Dad the Engineer would be dissapointed...Now with NEW questions!

[OkKeith]

OK... as a kid I played will all my Dad's drafting equipment (WAY before the CAD days!) and his precision measuring equipment. As an undergraduate Fisheries Biology student and later in Grad School I used all manner of precision gear for everything from measuring the diameter of fin rays to the thickness of fish scales. Its been A LONG TIME since I tried to read one of these things and for the life of me can't remember how to do it.

Anyone who can help me out... AND NOT TELL MY DAD?

OkKeith

[Mad Max]

Sorry I had to change it

In your picture you are at 1.635
the lines between 1 2 3 4 5 6 7 8 9 are .025 each
so the 0 5 10 15 20 ect is .005 .010 .015 .020
So your past 1.625 at the 0 below the 1.6 so go down to the 15 (.015) line and it lines up with the line above it.
1.625 + .015 =1.635

[Mad Max]

Take a picture of you measuring something and tell me what it is, and so I can see it well.

[OkKeith]

Thanks Mark!

I was sure having a brain fart on trying to remember how it all added up. Here is a photo of the limb pocket I am measuring. A Buddy says if I can render him a drawing in Sketch Up he can machine a block to fit in the limb pocket of this riser to accept the limb bolt and alignment pin.

Thanks again!

OkKeith

[Mad Max]

1.650 looks like the 0 line lined up with the .050 line
Mo better

[OkKeith]

I will bookmark that video!

I went through all kinds of field classes on measuring devices. Gram scales for weighing Field Mice in little linen bags, the "right" way to measure the length of a snake, etc. All thirty years ago. The Farmers, Ranchers and such that I work with now don't measure to that degree too often. I am more of a "pounds of seed per acre" or " square feet of brush per mile section" kind of guy now.

Thanks again! I am happy to be working on this compound conversion again.

OkKeith

[Mad Max]

My dad gave me a pair of calipers just like that when I started machining to learn on.
Micrometers read the same way until I got a pair of dial calipers.
It had me scratching my head for a while.

[OkKeith]

My Dad has been retired from being a Petroleum Engineer going on 15 years now. He designed flow control and volumetric measuring equipment. If you have ever been on an old oil pump site and ever saw one of the little boxes with the circular paper graphs, he helped design that when he was with the two companies National Tank and InvalCo. Way back when I was a kid, back when Tulsa, OK was the center of the oil biz. Most of my whole family was in the oil patch in one way or another as a Drilling Hand, Tool Pusher, Mud Logger, Engineer or something. Even several of my Aunts were Sups in the Accounting Dept.

None of them were sure what to say about the weird kid who decided to be a "Fish Biologist".

Thanks again for the help. I borrowed that set of calipers from a bow building Buddy. I think you can see epoxy finger prints on it!

OkKeith

[OkKeith]

Got it all measured and drawn up...

[Crooked Stic]

Mine has DRO.

[Mad Max]

1.650 is going to be to tight, isn't it.
get a piece of wood like that .180 x 2.25 and sand it down to 1.650 wide and see if it will fit.

[OkKeith]

For some reason the snap lines on Sketch Up wouldn't let me fine tune my measurements. I need to fiddle with it more.

In talking to my machinist Buddy and telling him exactly what I was doing, he recommended that we might make the blocks out of HDPE or Delrin. He thought it might dampen some vibration on the shot. I haven't looked at cost difference between block aluminum and these plastic products or the weight difference but I suppose it is something to think about.

Thoughts?

OkKeith

[Mad Max]

I don't use that CAD
So on your drawing you  decimal are to short 3.25 go to settings and get more decimals 3.2500 maybe
I don't know?????

[Flem]

Are those pieces going to be threaded? If so I think I would pass on the slippery plastic.

[Mad Max]

Did that help keith???

[OkKeith]

It did, Mark... thanks! I mocked it up with a piece of MDF. Depending on if I paint it, it will need some tweaking.

Flem...  I wasnt  planning on threading it. It's basically just a block to level out the limb pockets. The limb bolt holes are already in the riser. Total thickness is well under an inch.

OkKeith