God mode restorations
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Ok guys. I did some research today so I can understand. Think I have sussed it out. Did a picture with the calculation. If my calculations are wrong feel free to comment.
Have you worked out the circumference and then divided by number of holes? If so that gives you the distance between each hole along the arc of the circle.
PCD is the diameter so your example the PCD is 152.
Yes. I worked out the circumference and divided by 12 which is the number of holesHave you worked out the circumference and then divided by number of holes? If so that gives you the distance between each hole along the arc of the circle.
PCD is the diameter so your example the PCD is 152.
Yes got ya now.Have you worked out the circumference and then divided by number of holes? If so that gives you the distance between each hole along the arc of the circle.
PCD is the diameter so your example the PCD is 152.
Yes. I worked out the circumference and divided by 12 which is the number of holes
Yes i did notice it was a couple of mm out on the last hole. Is this because i have used a straight line to mark and not the arcThat will be a bit out if using that length in a straight line between holes.
Yes i did notice it was a couple of mm out on the last hole. Is this because i have used a straight line to mark and not the arc
Ok. I understand now. ThanksIf I needed to do this, I would mark a circle of a convenient size radius, and inscribe a regular polygon of the required no. of sides, by whatever method is easiest - by geometry for factors of 48 (step off radius around circumference to divide into 6, then half, half, and half again- this will give 2,3,4,6,8,12,16,24 holes), or with a protractor if necessary.
There is no way geometrically, to divide a circle into any prime number except 1,2 and 3 - AFAIK (And I seem to remember seeing a proof a LOOOOOONG time ago) so it will HAVE to be done trigonometrically, and by calculating a chord length
There are multiple ways to do it but.
If you think of a circle where a shape with the same number of sides as the number of studs drawn in it you will see the that a line drawn from the centre to each point creates a set of triangles equal the to number of studs.
So working with what you know to find the bits you don't
360 degrees in a circle divided by the number of studs gives you one angle of the triangle. You already have the PCD so you already have the radius which gives you length of two of the side so you have enough to work out the third side which will give you your dimension for marking out a PCD
The total number of degrees in a shape is N-2 x180 where N is the number of sides or in this case the number of studs. If you divide this total by the number of studs and then divide by 2 you have the two outer angles of the triangle which will also give you what you need to work out the unknown side using the radius.
Both of the examples achieve the same result but in a different way.
Keep it simple its not rocket science for most tasks........degrees 360 in a circle.....no need for the trig etc.......why do folks want to over complicate everything