Posting a project for comments

[Anonymous]

I would like to post my final class project for comments; it contains a bunch of parts files, an assembly, a drawing, and a presentation. I have it in a zipfile, but if you folks prefer I could post in another format.

Many thanks in advance

Joe Stavitsky

[JDMather]

Extrude your Board sketch 10mm (away from you (-z)).

[JDMather]

Start a new sketch on the XY plane (rather than the part face - always use origin planes when possible).

Sketch a rectangle as shown out in space.

Add circles at both ends from midpoint of horizontal lines out to endpoint.

[JDMather]

Add vertical construction line.
Change horizontal lines to construction.

(there is an easier way to do this dragging arcs out from lines, but if you haven't been taught....)

Add a coincident constraint between the midpoint of the vertical centerline to the projected orgin center point.

[JDMather]

Dimension the sketch as shown.

 

 Trim the insides of the arcs.

Then Extrude-Cut through all.

[JDMather]

Start the Rectangular Pattern tool and select the slot.

Select the hoizontal line for direction and set to MidPlane.

Set number of copies to 3.

Set distance to 42mm (be sure to change from Spacing to Distance.

It is almost always better to pattern features rather than to pattern sketches.

[JDMather]

Start a new part file to create u-bolts.

Sketch a rectangle as shown below the projected origin.

Add a coincident constraint between the top horizontal line and the projected origin.

[JDMather]

Add an arc to the top of the rectangle.

Add vertical line from center of arc to top.

Change the lines as shown to construction linetype.

[JDMather]

Start a new sketch on the YZ plane (don't create any workplanes that are not needed).

Project Geometry the endpoint of the vertical centerline from sketch1.

Sketch circle at this point diameter 7mm.

[JDMather]

Sweep the circle along the u path.

[JDMather]

Add the thread features and then the chamers (always do the thread before chamfer to get the correct length).

Save the file as Long U-bolt.

Save As the file Short U-bolt.

The file Short U-bolt should now be the active file.

[JDMather]

Double click on the thread feature and set to 26mm length (of course do for both).

Edit Sketch1 and change the 50mm to 36mm.

Save the file.

[Anonymous]

Why circles and not arcs on the board features?

Thanks again

Joe

[JDMather]

---

@Anonymous wrote:

Why circles and not arcs on the board features?

---

Arcs would be better - trying to avoid any problems (with center point, tangencies...)

The way I would really sketch that is with a line, drag arc, line, drag arc never leaving the line command.  But beginners sometimes have trouble getting a handle on this technique.

And since we aren't even in the same room....

[Anonymous]

Insufficient constraints on the hole feature again... sadsad. I haven't tried any constraints yet but what you specified as I'm assuming you found those sufficient. 

Will try from scratch with arc.

Also - maybe I misposted, but between the 3 holes there should be 2 raceways for the bearings - width 7mm, depth 7mm. I should do these same way as the holes, right?

Thanks again

Joe

[JDMather]

---

@Anonymous wrote:

Insufficient constraints on the hole feature again... sadsad.

---

When you get something like this you have two choices.

1. Keep working at it till you find out why

or

2. attach the file and someone with experience will tell you why within minutes

1 is good, but don't take hours beating your head until you try #2.  Whatever you do, don't ignore and leave unanswered.  Finding the how and why will pay off dividends in the future.

For the bearing slots - do one and then mirror the other. On something this simple there probably isn't any advantage of mirror sketch or mirror feature.

[Anonymous]

Second sketch, fully constrained. For some reason, the lines turned bule but the arcs didn't?

[Anonymous]

Can I change the amount by which I zoom in/out with the mousewheel?

[JDMather]

Forget drawing as arcs - draw as circles and trim as I first instructed.

You have an extra radius dimension (I didn't show to add any radius dimensions).

You are missing tangent constraints between the arcs and the lines.

If I remove the radius dimension and add a tangent constraint - the sketch turns color.

[Anonymous]

I can see where missing constraints are a problem, but does absolutely everything need to be dimensioned? For instance, do construction lines need dimensions?

[Anonymous]

Updated board, ubolts, and eyebolt. Let me know if all is up to spec and I will complete.

Really hope I can build this, but I'm worried that some of the detail work is <3mm. A worthy test of my dremel skills at the very least.