Problem #1

[brucer]

I would use a right triangle with hypotenuse of 1.5",
figure for side opposite and side adjacent of the triangle relative to the 30degree angle..

mirror the xy coordinates throughout the bolt pattern on the the corresponding locations



also guys with mills and even lathes at home, i would suggest buying an Illinois Tool Works Trigonometry Tables book.. usually called the lil orange book, its worth its weight in gold, as handy as the machinists handbook.
example: http://www.amazon.com/Trigonometry-Tables-Involute-Functions-Illnois/dp/B0015CTSF0

 

[GK1918]

If this is any help, there is an on line bolt hole calulator probably google it and save it to favorites.

 

[rmsflorida]

Re: Problem #1...

Lay out a six hole pattern ?
Drill holes ..using the drill press
Keep It Simple !
Scribe the diameter....
Use a divider caliper..
Trial and error ...in a couple of moments you can walk off the six spaces one way then go back the opposite direction to check the intersecting scribed lines..

Accurate and simple...

Robbie
Robbie's Machine Service

 

[Tony Wells]

Robbie, for six holes, there is no trial and error. The radius you drew the circle with is the chord length, so once you have the first hole located, marking off the other locations is simple, because your dividers or compass is already set.

 

[rmsflorida]

SEE ...It's simple !!!`


Now 1-5/8 drill hole in a 36 hole pattern..16 foot dia...
I got to post a pix ...Oh.. a good one ...from the rock mines down this-a-way!

20 post ...hurry!

Robbie

 

[Tony Wells]

Ahhh, now we're looking at 10 degrees on an 96" radius. Hint, hint.

Looking forward to your pictures.