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Unable to draw a mallet (uses arcs)


emazur

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I have another exercise in from the book "Discovering AutoCad 2020" - this one is causing me trouble right off the bat. This is the first chapter using arcs. I hope I at least got the very bottom correct but everything else is throwing me off. Like the 2 horizontal bands on the the top/bottom of mallet head (on the drawing below where it says 2 7/8) I wasn't sure what the distance was supposed to be from the top of one band line to the next - I just assumed 1/8 and tried to move forward from there. But the very bottom of the mallet is 1/8 and on the drawing it seems the band is supposed to be at least twice as thick in comparison. For the L/R arcs above the bottom and between the first band I selected:

Arc > start, end, radius

and inputted "1" for the radius

Not sure if I did that correctly

And how to draw the radius between the top/bottom 2 bands - I'm clueless though I suspect the measurement of 1 7/8 has something to do with it.

The vertical line on my attached drawing is just temporary as are the horizontal lines.

 

*You need not give thorough point-by-point instructions on what I should do (as I think I'm just going to move on for the sake of progress) and forget about the handle, but I'm hoping at least for some pointers on the mallet head*

chapter 5 drawing 5-5.dwg

05mallet.jpg

Edited by emazur
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The instructions give you most of what you need to know. The ARC command can be used several ways--the method you use depends on the information you have available and where the arc has to go.

 

It may help to draw some construction lines. There's a dashdot line through the center of the mallet, for instance, that you can offset (use the OFFSET command) to get the outer limit of the long arc in the center. By drawing a centerline through the handle, you can create an intersection at the center of each arc and use those to locate the center points. (Hint: use the SNAP filters.)

 

As always, there are multiple strategies for any task in AutoCAD. Find the one that you're most comfortable with.

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I would start by drawing all the straight lines starting from the top (or bottom), and side to side, including the centerlines since, per the included image, as you are provided distances between lines and in a couple of cases the length of the line(s).

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After creating the straight construction lines as suggested by @ReMark, you can create several of the arcs by specifying the start point, a point along the arc, and an end point.  Be sure to specify these points in a counter clockwise direction.  For example, use points A, B and C as shown below.

Note, there is a minor error in the drawing.  The two arcs that meet at the green circle are not tangent and therefore there should be a vertical line (green) on the handle as noted.

image.thumb.png.fd81b6636c5cb15101275d3b6725a7c7.png

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Still you lack a height of the two horizontal bands.

 

Perhaps this is partly an exercise in initiative!

 

Draw the bands to any dimension that looks good.

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That is certainly a solution, but would make the side to side dimension of the band 3' 0 1/8" which is wider than the mallet head.

 

Perhaps that is what is wanted, but one could say that this is not a first class example of a drawing exercise.

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Quote

but one could say that this is not a first class example of a drawing exercise.

 

 

Agree.  In addition, the two parts should be detailed separately not together in an assembly drawing.

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However, using the supposition that the end of the band is in line with the mallet head, one can take an arc of radius 1/8", such that the perpendicular bisector of the arc to the chord (saggita) is 1/16". This gives a chord length (height of the band) of 55/256" which is tricky to dimension when seemingly the accuracy is 1/8".

 

Picture doesn't look too bad.

 

 

mallet.PNG

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