Cheap or free low power use CAD system

Since I brought this back to the top, I'd like to ask someone that actually knows what they are doing, to take this adapter ring I drew in SketchUp, and make it look beter, so I can give a pretty drawing to a local machinist!

I exported, and used Paint to add the dimensions and such, and since all my drafting classes were over 35 yr ago, I probably did not do them correctly, but that's my best! Thats also the best circle I can get out of SketchUp... may be me?

My Beemer thread tells why, but this ring is a spacer with 4 counter bored holes on the BMW bolt circle (radius), and 4 tapped holes for the aftermarket aircraft gas cap, at a slightly smaller radius. I figure make it as easy on the machinist, and I'll tap my holes myself!

When you're making a circle in SketchUp, down in the bottom right corner of the screen is a little input window.  In that window is a number - looks like yours is set to 12, or the number of segments in the approximation of a circle.

Try creating a new circle - click in that box and set it to 64 or 128.  That will give you a smoother circle.  Because SU deals with vectors and planes, it will still be an approximation, but it will be a much better approximation.

[edit]  OK, that tip is for an older free desktop version.  In the online version, while drawing your circle, ctrl-+ to increase the number of segments.  64 should be fine.

Machinists like pretty drawings, but could easily build off that.  However, your counterbore diameter is missing.

In reply to Duke :

Cool. I'll have to check that out tonight when I can access the computer. 

put the Ø diameter symbol in front of your dimensions and it doesn't really matter :)

ProDarwin said:

Machinists like pretty drawings, but could easily build off that.  However, your counterbore diameter is missing.

I did a dozen or so contracts as a machinist, mostly during outages, and I was as likely to get verbal info for a one off part, as anything! I can do a hand drawn, but figured this was a good learning opportunity!

Duke's advice made it look MUCH better! And I used your suggestion for the Dia symbol, even though I had to draw that myself, when I modded SU. I didn't have my bolt circle measured exact, is why I didn't include counter bore dia on the first dwg... it would have actually ran off the part - was hoping to slide that by, but ya got me! I just noticed I don't have the 1/2' thick this time... prolly would not have, but I knew you would.

This one has the radius of the bolt circle, and the dia; I will remove one. What looks better, in your opinion?

In reply to 03Panther :

Glad that worked!

I would go with radii, but either works as long as you're consistent about it.

In reply to Duke :

Consistently does count, as in so many things!

Thanks. Now one day I gotta learn one of the other formats.