Help fluted tapers

[mailee]

Can anyone tellme how I can make a round fluted tapering column in
Sketchup? I have been trying to puzzle it out but it has me beat. I want to draw a bed post for a four poster bed with a tapered fluted column at each corner but I can't seem to get to grips with it. TIA. :?

 

[SketchUp Guru]

I'll work up a tutorial for you and post it. So you want the colum to be tapered with flutes that run out at the narrow end of the column?

Out of curiosity, how will you make this in wood? How many flutes?

 

[Steve Maskery]

At the risk of stealing Dave's thunder here (and that's not my intention, honest!), this is how I would go about it. I've not tried it, so this may be claptrap, but we'll see if it's the same approach as Dave would take, or maybe there is more than one way to skin this particular cat.

First I'd make a plain column.

I'd make the base circle segment count a multiple of the number of flutes I plan to route, so for 6 flutes the default 24 would be fine. Make the cylinder, select just the top face and scale that down, using the Ctrl key to scale it around the centre rather than the opposite side.

Next, we have to make a positive version of the flute. In a separate area of the model, draw a long thin rectangle and draw a half-round on each end. Remove the ends of the rectangle so that we have the flat profile of a sausage. Draw a centre line down the middle of the profile - we can use this later for positioning.


Draw a semi-circle perpendicular to the lot.

Using the Follow Me tool, spin the profile through 180 deg, using that semicircle as the path, to create a 3D sausage. Delete the semi-circle.

Incidentally, I can see there being problems here, so if you get any unexpected results, simply scale the whole thing up by 100x, and then scale the end result down again.

OK, we have a sausage with a line down the middle. We are going to use this to remove timber to make the flutes.

Make the sausage into a component.

On the cylinder, draw a line from one segment junction on the base to the corresponding point on the top circle. This line must be flat on the cylinder - if you get it offset, even by one segment, it will not lie on the surface. We will position the sausage on this line.

Drag and rotate the sausage, using its centre line, until it is in position on the line on our cylinder. Copy it around the cylinder.

Select everything and do an Intersect With Model.

Erase the sausages and the cut surfaces of the cylinder.

I think that's the job done.

Now I'll be very interested to see if Dave tackles it the same way or whether he has another approach. Either way, I certainly think it will make a smashing tutorial.

S

 

[mailee]

Thanks Dave and Steve, I will try and get my brain around that one Steve maybe later when I have more time. If I make this Dave it will be on the lathe with a registering device to give me eight flutes around the circumference. I have made one before but never made any plans of the beds not having a computer back then. Thanks for your time guys.

 

[SketchUp Guru]

Steve's method would work for stopped flutes although he might be working too hard to get the sausages. Now, I'm hungry. You always manage to squeeze food into a conversation, Steve. :lol:

One correction, though. Scale about center is invoked with Ctrl, not Shift (Option on Mac)

I'll work up my version of the stopped flutes. In the meantime, here's a quick way to draw unstopped flutes on a taper. The flutes taper, too so they may not be techncially accurate but they are quick and for an illustration, I doubt it would be noticeable.

Circle with semi circle of desired flute size. Copy the semicircle around the circle as many times as needed. Make sure the arcs intersect with the edge of the circle.

Delete the segments between ends of arcs.

Push/Pull to height.

Select top face and Scale About Center to desired diamter.

 

[Steve Maskery]

Dave,
Thanks for the correction, duly amended.

You see, I knew there was more than one way to skin a cat.

How do I make sausages more quickly/easily?

Cheers
Steve

 

[SketchUp Guru]

Steve, what is it they say about government and sausage? It's better not to see how they're made.

Your method of making sausages actually is very simple. I'd probably make a whole one because it would be easier to draw the circle perpendicular to the centerline.

And maybe try this:

• Draw the cylinder and taper the top with the Scale tool as Steve described.
  Under View, tick Hidden Geometry.
  Put a guideline along one of the hidden edges on the taper.
  Put in a guideline on the centerline of the taper, too.
  Untick View>Hidden Geometry.
  Triple click on the taper with the Select tool.
  Right click on it and choose Hide.
  A few quick guidelines to layout the location of the sausage.
  Draw in the sausage profile.
  Draw a circle above or below the profile perpendicular to the centerline.
  Do the Follow Me thing.
  Delete the circle.
  Select the sausage.
  Rotate copy the sausage for as many flutes as desired.
  Unhide the taper.
  Select everything and run Intersect with Selected.
  Delete the excess sausage material.
  Correct the face orientation. (You could reverse the faces on the first sausage if they don't end up reversed during Follow Me. This would remove the need for this step.

 

[mailee]

Thanks Dave, It was the sausage type of flutes I was looking for I know how to make the sausages but it was placing them on the cylinder that gave the problems. I will give both of these methods a try maybe tomorrow. Thanks again for all your help guys.

 

[mailee]

Well thanks to all your help guys I managed to cobble this together. Looks like I am on the right lines although it did take some doing. I am a slow reader. :lol:

Problem now is can I remember how I did it all? Will run through it again following your instructions to be on the safe side.

 

[SketchUp Guru]

From what I can see it looks good. The only things I can suggest are these: Correct the face orientation in the flutes. They show as reversed in the image you've posted. When you make the sausage, you could reduce the number of segments used in the arcs and the circle for the Follow Me path without hurting anything. It'll help to reduce the entity count and keep file size down a bit.

Keep up the good work.