I'm on a roll today! Please help me :(

[Ameldur]

Hi guys, 

I just went back to a part i was unable to do a while back and im still having some issues. The problems I am having are at the top of this crankrod.

1. By looking at the drawing i can not see how thick the two (I don't know what to call them) "things" are supposed to be, only how far they should be apart (15mm). What am i overlooking?

2. The R5 fillet that joins the bottom cylinder to the top part of the part, how would I do this? Been trying to fix this with no luck.

Attaching my IPT file (i've guessed the thickness here)  with my current progress and the drawing I am following.

Thanks in advance.

[LT.Rusty]

If it makes you feel any better, I don't think you're missing anything there ... looks to me like the original drafter missed some opportunities to get a dimension in there, though.

Making a guess, I'd say it's supposed to be 4mm thick, though. I'm arriving at this conclusion in the following way:

Looking at the side elevation, we see that the bottom of the bracket is 16mm below the centerline of the thru-hole. This is in turn 8mm below the top of the part, for a total of 24mm. The bracket is 20mm deep, according to the other view, leaving us 4mm of thickness. Visually, the sides of the bracket look like they're the same thickness as the bottom of it, so ... a little bit of brown-fingered estimation says probably 4mm. That's just a guess, but it's probably not too far off.

[JDMather · Accepted solution]

Sometimes bringing image into sketch helps.

[Ameldur]

Thank you both! 

From looking at the .ipt file JDMather's sent, it looks like i should just perform a revolve (for the fillet), please corrent me if i'm wrong.

Also, how do you add an image to a sketch? Really good tip for the future 🙂

[Ameldur]

Tried now, can't get it to match 😕

[JDMather]

Here is how I might model the part. (notice that I did not use Loft or create any extra workplanes)

Use the most primitive geometry possible and avoid creating extra workplanes dependent on existing geometry.

Also, you have the drawings for the mating parts to help figure out logical values for missing dimensions.

To place an image in a sketch

start a new sketch

Click on the insert image tool and place desired image.

Add a horizontal constraint to the image box (or dimension angle if image skewed).

Dimension one edge of image box (I recommend long edge).

Sketch line from dimensioned location on the drawing (the longest dimension).

Dimesion this sketched line.

Edit the image box dimension and multiply the dimension by (known dimension/measured dimension).

This will scale your image to correct size.

Locate the image relative to the origin and Fix constraint or dimension to the origin.

If image is a photograph - use only as reference as there will be parallax error.

Also, after inserting the image I right clicked on it in the browser and set Properties for the background as transparent.

[Ameldur]

Thanks again 🙂