Making "Dreamery"


Mark J
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I completed the sanding and got a nice surface. I think the pointed inside waist line came out well, but time will tell.

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And with a MS wipe down

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In some ways it’s a shame that a lot of that beautiful grain pattern (and a lot of sanding effort) is going to be cut away, but next up is making the template to guide in removing that wood.

To begin with I returned to Fusion 360, to work out some geometric details. The template is basically a four pointed star. The tip of each star meets the sides of the as yet un-cut basin at an angle. It’s convenient if that angle is a whole number of degrees, and after some minor tweaking 21* seemed to work without changing the location of the center apex. If you recall from the original drawings there is a “slit” in the waist line of the base, which I think will be an important design element. The center apex’s position determines the depth of that slit.

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Having worked out the geometry I printed a diagram. Since all four points of the star are the same I only had to depict one of them.

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Then square up a piece of plywood on the Incra, mark the diagonals and find the centers of both faces with a Starrett combination square. Find the cardinal lines, again using the combination square.

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Now mark off the position of the central apex and mark a line ¼” from the corner (including along the edge of the plywood).

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I made a discovery, a piece of ¾” ply fits perfectly between the fence rail and the table on my saw. Convenient for marking the edges.

Carefully draw the line connecting the two points. Confirm the accuracy with a digital protractor.

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Rinse and repeat until all eight sides of the four points are drawn. Then do the same on the other face.

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At this point I have the cut lines drawn, but there was some debate in my head as to whether to cut the template out on the band saw or whether to use the table saw. I had recently made the 45* drilling cradle on the TS, so I new the trick is to flip the board from the A side to the B side between cuts so that two saw kerfs miss each other.

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I decided to go with the TS. The BS would make a prettier cut, but all my miter gauges fit little loose in the BS slots. I could (and should) fix that with a little shimming, then align everything carefully… Or I could go with the Incra that’s already set up and ready to go. I set the Incra to 21* and slid the fence far to the right.

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Then I used a stiff plastic ruler (non-conductive; it’s a SawStop) held along the flat of the blade and passing between the teeth to confirm the saw blade was aligned with the cut line and further confirmed the saw teeth would strike the cut line as well.

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Then switch on and cut carefully just the right distance

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Then flip the board over and repeat the operation on the B side.

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You’ll notice that the second cut was ever so slightly off the line. That is a simple graphic demonstration of the fact that the world is not perfect, hence my motto: Be as precise as you can, that way your mistakes will be more accurate. This is as good as it gets and I believe will be good enough.

That operation gets repeated three more times, but the next cuts are a little tricky as some of the side is now missing. So now you see why the star pattern didn’t go all the way out the corner, but stopped ¼” short. First I like what that does for the base’s form, but it also insured there would be enough of a flat left to reference for the subsequent cuts.

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With the remaining cuts completed we have a star.

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Now the agonizing decision, do the triangle cutoffs go in the garbage or the scrap bin. :)

Final step is to drill a clearance hole for ¼ x 20 machine bolt and a recess for the head and washer.

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The base piece is taken down from the lathe and removed from the screw chuck. The bolt passes through the hole in the template and up through the hole in the sacrificial block. And the two are secured tightly together.

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Recall that the screw chuck uses a 3/8” screw with a 5/16” clearance hole so the ¼ machine bolt has some wiggle room which allows me to correct any tiny misalignment. Which as you can see is pretty good. It also means that the screw chuck;’s threads don’t get chewed up.

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That’s ready for starting the cutback process, but I’m not, time to go watch TV.

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  • 3 weeks later...

No, I have never really turned anything besides wood.  I imagine at some point something with acrylic or resin will get on the lathe.  I would love to have a metal lathe someday, but that's a whole nuther thing entirely.

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Question. Could you run the lathe clockwise and use the head stock in the 0 degree position and just cut on the back side of the bowl? It seems like all the work your doing is to accomplish basically standing on the other side of the bed. Instead of standing on the other side of the bed reversing the motor to run clockwise would accomplish the same thing would it not?

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Yes, I forgot to mention those considerations. 

I could have put the motor in reverse, and with the tool rest repositioned used the tool to work on the back side of the basin.  BUT, there is a serious potential problem you have to be constantly watching for.  The chuck and spindle are right hand threads, so when reverse turning you are tending to un-screw the chuck from the spindle.  True, there is a set screw to resist un-threading, but it can only do so much.  You have to keep an eye on the spindle.  (By the way reverse is generally not a problem if you're just sanding).

An alternative approach is to do just as you suggested.  Leave the lathe motor in forward, but stand on the back side of the lathe.  This works well. The caveat here is that the controls including the emergency stop are usually on the front of the lathe.  In my case I'd have to move an equipment table and the DC setup to get space to stand behind the lathe.  Lot of power cords, too.

Actually, now that I have the outrigger setup what I find myself wishing for is a barstool.  I'm thinking that would get my head lower and my back straight.  

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  • Mark J changed the title to Making "Dreamery"

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