# Thread: How to draw Cam lobe

1. ## How to draw Cam lobe

Registered forum members do not see this ad.

Hi everyone, when its come to autocad i'm a total noob. Thank to cadtutor.net and you guys i learn bits here and there. You guys are great sources when i have no where else to go. So i'm here today with this problem that have troubled me the past couple of days. I have included a picture of the drawing. I could draw the 45 radius Arc that goes from 0 degree to 90 degree. The other Arcs somehow i just can't. Hope you guys can help me on this

Many thanks

2. Anyone able to help this member out? I tried but I always come up one arc off. Obviously I'm doing something wrong but I don't have the time to figure it out right now.

3. Originally Posted by ReMark
Anyone able to help this member out? I tried but I always come up one arc off. Obviously I'm doing something wrong but I don't have the time to figure it out right now.
I agree.

Gene

4. I'm going to *bump* this thread as I see JDM is back from his extended vacation. It must have been final exam week at the University of PepsiCola.

I'm willing to venture a guess he'll say it can be done using AutoCAD Inventor.

5. 0000000000

6. This looked like an interesting exercise and having a little time on my hands I gave it a shot. I'm not an ME but would be curious how close I came to getting this correct.

I started with the known center of the keyed hole and the 45R on the right. I then drew two circles, 61R and 80.6R respectively (red dashed circles) and just moved them using the quadrants and the centerlines of the keyed hole. Then I constructed the two lines which are 79° to each other, referenced to the 59° angular dimension given. I trimmed these red circles using the construction lines and then filleted the last part of it together using a radius of 47.3°. The ending cam shape I then joined as a polyline, it's shown in green. Like I said, I'd be interested to know if this is correct or not. I'm sure others may use different method to construct it. That's the nice thing about AutoCAD. There's always more than one way of doing something.

7. Originally Posted by ReMark
I'm going to *bump* this thread as I see JDM is back from his extended vacation. It must have been final exam week at the University of PepsiCola.

I'm willing to venture a guess he'll say it can be done using AutoCAD Inventor.
Final exams I was with J.D. and ahhhhhhh yes it was final exams.
If we had the cam profile along with the cam itself it's easy to create. But from what I know there's a lot of missing data to create it propery.

8. Nothing from anyone else? Not even the OP? If anyone is interested I'll give it a shot and post the results.

9. Originally Posted by Murph_map
Nothing from anyone else? Not even the OP? If anyone is interested I'll give it a shot and post the results.
i have been trying for the last 2 days off an on and i can not even come close with the information given. Wish i could look at Bill Tillmans drawing but LT 2000 will not open anything newer. Still going to work on it though.

10. Registered forum members do not see this ad.

If we assume all of the arcs are tangent and they stop/start at the angles given - there is one solution. (none of the arc centers are on any of the construction lines, but it is fully defined with the given dimensions) (BTW - solution was found in less than 10 minutes.)

Tangent Arcs.PNG

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts