# Thread: Dolphin Partmaster help for newbie?

1. ## Dolphin Partmaster help for newbie?

Greetings,

I am a rank newbie at cad (downloaded the Partmaster product and video tutorials a couple of days ago). I have been attempting to create a very simple two-dimensional drawing so that I can send it to someone with a cnc router before Monday. and I am at wits end, and could use some pointers.

I want to draw two parallel arcs spaced .25” apart. I then want to enclose the arcs (at both ends) with a .25” radius. (The goal is to cut a groove through which a ¼” bolt will slide. There will be multiple grooves, identical in length, spaced evenly around a single point.)

Two problems which I have been unable to overcome (through two days of trial and error, and I’m getting sleepy):

1- I can draw the parallel arcs, but I cannot determine how to make the lengths of one pair of arcs match the next set.

2- I cannot enclose the end points of a pair of arcs with a .25” radius. I have tried in Partmaster to draw a two-tangent arc of .25” diameter from endpoint to endpoint, but the software tells me “no can do” without an explanation. I have tried all the snap modes, and everything else I can think of. At this point my brain is mush.

I hate to ask, but will someone here give me a pointer or two, or quick explanation of how to accomplish the goal? I promise not to hound you in future!

2. Well, a bit more perseverance has paid off: I figured out that to join the endpoints of two parallel lines (or curves) with an an arc (semicircle) I must first draw a line between the endpoints, place a point on the midpoint of that line, and use the midpoint as the centerpoint for the joining arc.

One issue solved.

3. Two lines .250 apart need .125R to conect with 180arc. some demos wont let you save copy past or print . Good luck

4. Kevin, thanks for the reply. Got it.