Cardinal Points

[SketchUp Guru]

here

 

[ColeyS1]

Just thought i'd have a quick watch of your video. Its something i was going to ask you how to do :!: 8)

My work mate has a wicker basket he uses to keep logs in. He'd like to cover the inside with fabric so the dirt doesnt go everywhere. The basket is round and has a bigger diameter at the top then the bottom- cone shaped.

So your video is perfect for drawing it (hammer) but.................................... what would the process be (if there is one) to peel away the cones face and use as a template for sewing ? I think i can just about figure out the shape of the bottom piece of fabric :lol:

Sketchup is really starting to change the way i think about doing things !!!!!

Thanks

Simon

 

[SketchUp Guru]

Simon, I'm glad you are finding that SketchUp changes the way you work.

As to creating the pattern for the fabric, you can unfold the shape once you've drawn it using the Unfold Tool plugin. Keep in mind the accuracy of the pattern will depend upon the number of sides of the circle. The more sides, the more accurate.

 

[ColeyS1]

unbelievable !!!! appreciate your quick reply Dave . I'll give this a try later 8)

Thanks

Simon

 

[ColeyS1]

Well heres my effort.

Not drawn to scale as i haven't got the accurate measurements. Whats the best way to get an accurate flat image of the unfolded piece ? The size of it varies dramatically depending on where i orbit around the unfolded piece.

sorry to veer off topic :wink:

Simon

Oh :idea: Had an idea to start unfolding by first selecting the front view option. Am i on the right path :-k

 

[SketchUp Guru]

You can either rotate the flattened assembly to align with the axes and pick the correct standard view. Also set the camera to Parallel Projection to create a 2D view. You could also right click on a face and choose Align View. You'll still want to use Parallel Projection.

You could dimension the pattern and use those dimensions to layout a full size. It is possible to print out a pattern directly from SketchUp but it's a pain to set up. If you e-mail the SKP file, I'll make you a PDF that you can print full sized.

 

[ColeyS1]

Thanks for the offer Dave,i just had a rough measure and its nearly 2metres in length- think paper might unsuitable for this size ?

The basket is 275 high, 260 diameter at the bottom and 360 diameter at the top.

If there was a way to somehow measure the unfolded radius, i could mark it directly onto the fabric using trammels. There is a very slight risk we may be majorly overcomplicating things :lol: (hammer)

I think the unfold tool could be really usefull for marking out flared stair string housings. That way the curvy string could be 'unfolded' flat to take measurements from, then transfered easily to the bendy wood. Think im becoming an addict =P~

Simon

 

[ColeyS1]

Thanks for the offer Dave,i just had a rough measure and its nearly 2metres in length- think paper might unsuitable for this size ?

cough 1 metre. Got my diameters and radius's all fuddled up

 

[SketchUp Guru]

I think you're right about the paper thing. I would make a component of the unfolded pattern. Then I would trace over the edges with the Arc tool. Before tracing, set the number of sides to match the number you used for the circle or even higher to gain more precision. When you select those drawn arcs, you'll be able to see their lengths in the Entity Info box.



Actually you could get the sum of the the lengths of the segments by selecting all of them at one time.

As for measuring for a curved stair stringer, you'll want to increase the number of segments making up the curve so you get as much accuracy as possible.

 

[ColeyS1]

Hello Dave,

just to make sure, are the measurements on your drawing for the lengths of the curve ? I'd still need to find out what radius of the actual curves are though to set me trammels (3 metres ish :-k ) Are there any huge differences between the free version of SU and the Pro version ?

Thanks
Simon

 

[SketchUp Guru]

Those are the lengths of the arcs but the radii can be determined either by looking at the Entity Info or by dimensioning them.

The main differences between the free and pro versions are these:
-More import options w/ Pro
-Solid tools w/ Pro
-LayOut w/Pro
-Style Builder w/ Pro

LayOut is the program for making documentation from your SketchUp model. It takes the scenes from SketchUp. You add text, dimensions, photos, etc and make a slide show or a PDF document. In LayOut you can very easily set a scale for your SketchUp view so if your paper is large enough, you can make a life size illustration. Also, if you edit the SketchUp model, you can quickly and easily update the document in LayOut.

Style Builder makes it easy to create Sketchy line styles of your own. Many of the SketchUp images I've posted in the last few months are done using line styles I created from my own hand-drawn lines and Style Builder.

 

[Shultzy]

Simon, It's been a long time since I studied Technical Drawing, but I seem to remember how to unfold a conical shape.

Draw the circle equal to the top diameter
Draw the truncated cone shape, which is the front view of the basket
Project the sides down to find the intersection
Draw two circular arcs, centre at the intersection, radius top and bottom of the basket.
Divide the circle into 12
set compasses to 1/12
Step 12 around the top arc
Join last point to intersection
The resultant strip is the correct shape but needs extra material for sewing.

You can have the skippy if you pm me your email address

 

[SketchUp Guru]

Hey! That's a good process to know if you have to do it on paper or want to draw out a full size template.

Out of curiosity, where do the 12 come from?

 

[Shultzy]

The twelve can be any number. You could use the radius of the circle and step 6 times or you could divide the circle into 24, it depends on how accurate you want to be

 

[SketchUp Guru]

Oh. I see. Thanks.

FWIW, I redrew the drawing and added the radius dimensions.

 

[Shultzy]

It's amazing I can remember after 44 years. I used it in metalwork to make an oil can from sheet metal.

 

[ColeyS1]

Thanks for adding the radius's for me Dave :wink: I was going to try working it out using a formula (1/2 span squared + rise square / 2 times the rise. You've saved me the hasslle though. I tried the entity info but all it seem to do was tell me the length of each segment. Apologies for steering your thread so far off topic. - Im trying to resist #-o

Shultzy, I like the way you've managed to demonstrate it. It seems logical seeing it like that on paper- ruddy clever too !!!!! Im going to draw it out on paper like youve shown me when i get chance. I find stuff like this fascinating. I once bought a book from APTC (workshop math) hoping it would contain loads of usefull info like this- it was hugely dissapointing. Your diagram almost warrants a place in a lever arch file titled 'usefull diagrams and formula' .............(hammer)

Thanks

Simon

 

[Shultzy]

Simon, thank for your appreciation, feel free to copy it. You can have the Sketchup file if you want.

The technique is called patterns, I knew it as developments, which show the size and shape of a flat piece of material needed for later bending or folding into a three dimensional shape.