Latest Stools

This is the place to post images of work produced using Aspire
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rscrawford
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Latest Stools

Post by rscrawford »

Here are a couple of the latest stools I've made. These 17" tall stools seem to be the most popular, and the maple/walnut mix seems to be the most popular wood. These are pretty much all done on my Cobra, except one hidden dado on the leg, which was done on my tablesaw. The visible dados on leg were done on the CNC. Almost all 2D toolpaths, except the transition from the joint to the leg, which was 3D.
Stool1.JPG
Stool3.JPG
Stool4.JPG
Stool5.JPG
Russell Crawford
http://www.cherryleaf-rustle.com

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zeeway
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Re: Latest Stools

Post by zeeway »

Very nice and an interesting design. Is that a particular style?

Angie

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rscrawford
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Re: Latest Stools

Post by rscrawford »

Just a style I designed several years ago. Utilizes a 'Sam Maloof' style locking joint for strength; most people seem to order the contrasting woods in the legs and top to highlight the beauty of that joint.
Russell Crawford
http://www.cherryleaf-rustle.com

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zeeway
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Re: Latest Stools

Post by zeeway »

Then I guess we should call that Crawford style... :)

Angie

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zeeway
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Re: Latest Stools

Post by zeeway »

Well, RS, from your posts on stools and some other posts on chairs, I am getting interested in trying to make a Maloof-design, low back chair from Scott Morrison's plans. I thought it would be fun to see how much of it I could make on my CNC machine. While waiting on the plans, I thought I would try to make a stool to your design with the Maloof joinery. Well, my hat is off to Mr. Maloof, as well as to you. Getting those joints to fit as pretty as you show them is not easy.

I decided to make my prototype out of yellow pine - I had some left over from another project, and it is inexpensive. I made the top (14 inch diameter) earlier today with the proper pockets for the joinery, and I was felling pretty smug.

For the legs, I guessed that the head end of your legs was 2 inches wide, but I decided to go with 1-1/2 inches to match my stock. I machined a test leg (top only) to test the fit, and while I can make it work, the fit as viewed from the top is not perfect. I machined the legs from each side, and getting that radius that comes around to front face (top left on picture below) is not working well for me. For some reason, my design leaves a little ridge on the front.
Test Leg.jpg
But never fear, I am too stubborn to give up. Anyway, kudos to you for those pretty stools. And if you have any tips to share on achieving that fit, I would be happy to hear them.

Angie

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rscrawford
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Re: Latest Stools

Post by rscrawford »

My blanks are 2.5" wide and 1.75" thick. I drill 3 holes in each end of my blank - 2 of them are index holes and the middle one is to bolt it to the jig. It sits on the jig so the wider dimension is vertical (so 2.5" high).

I had to design the head of the joint in Rhino because I couldn't do the 14" diameter curve on the back of the leg (to match the seat) and the complex transition from the joint to the leg in Aspire. But then I imported it to aspire.

I use a vacuum jig to plane the board down to exactly 2.5" wide and drill the index holes. This has to be EXACT. Then I bolt it to my jig 4 at a time and cut the first side. First I plane 1/2" off the leg portion, and do a profile cut 1.25" deep. Next I do a finish toolpath with a 1/2" ball nose just over the complex head of the leg. I make a profile pass down each side of the leg with a 1/2" radius round over bit, then cut the dado in the joint with a 1/2" endmill. Flip and repeat. I can cut all 4 legs in exactly 21 minutes per side (nice having the ATC for this). I cut the dado on the face of the joint on my table saw after I saw off the 1" square tabs on each end.

When finished, the legs are a pretty precise fit and I don't have any shaping to do by hand. They match the curves of the seat almost exactly. I'll post pictures of my jigs when I get home tonight.
Russell Crawford
http://www.cherryleaf-rustle.com

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zeeway
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Re: Latest Stools

Post by zeeway »

Thanks for the tips, RS. I'll give it another go next week.

Angie

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rscrawford
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Re: Latest Stools

Post by rscrawford »

Here are the jigs I use. The vacuum jig has a recessed pocket that the gasket sits inside, so the gasket is just proud of the surface. The area inside the gasket is also recessed to provide the vacuum area. There is no plenum because the wood is so thick that the vacuum will not deform it.
vacuum jig 1.JPG
vacuum jig 2.JPG
vacuum jig 3.JPG
Russell Crawford
http://www.cherryleaf-rustle.com

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Re: Latest Stools

Post by ScottBot »

Beautiful work.
I really like the joinery on the legs too.
Those stools are a fine display of craftsmanship.

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zeeway
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Re: Latest Stools

Post by zeeway »

Thanks, RS. I did figure out my problem on cutting the .5 inch radius...when the tool is going "down" the radius, as the radius approaches near-vertical, each step gives a large drop in z, producing some lines in the finished profile unless the step-over is very small. I will have to admit, there are times I need a cove radius cutter instead of a 3d profile.

Angie

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rscrawford
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Re: Latest Stools

Post by rscrawford »

To prevent that large drop in Z, I model a rectangle that is .75" lower than the part I'm cutting and .5" wider. This just creates a 'bottom' so the bit won't drop past that point (important because my piece is 2.5" thick and I don't want the bit to try to drop a full 2.5" and drive the collet into my workpiece!)
Russell Crawford
http://www.cherryleaf-rustle.com

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rscrawford
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Re: Latest Stools

Post by rscrawford »

That was my 'old' set up for making stool legs. I am just about finished remaking my whole table, and now I'm remaking all my jigs.

Here is my new jig for the tops. I cut an indexing plenum out of 1/2" aluminum with a vacuum hole in the centre. This will index my fixtures exactly in the same place every time for quick set-up.
stool top jig 1.JPG
The underside of the fixture is pocket cut .125" deep, leaving a lip around the edge that fits exactly into a set of grooves on the aluminum plenum. This is what indexes the fixture to the plenum.
stool top jig 2.JPG
The top of the fixture has a hole drilled into the vacuum plenum beneath, so the vacuum will come up through. The gasket sits in a shallow pocket. I set my 1.75" blank directly on this and turn on the vacuum (I use a venturi vacuum with a MAC valve that is set up in Wincnc to turn on and off with g-code).
stool top jig 3.JPG
Then little indexing blocks set into pockets to index the blank when I turn it over to cut the other side.
stool top jig 4.JPG
The completed stool tops can be stockpiled, and when I need one I can place it back on the jig and do my inlays in the top.
stool top jig 5.JPG
Russell Crawford
http://www.cherryleaf-rustle.com

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rscrawford
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Re: Latest Stools

Post by rscrawford »

Here is the dry fit of the joint, straight off the CNC. I usually don't dry fit, because it is very hard to get the pieces apart. I glue with a 5 minute epoxy and that lubricates the joint so they slide in easier.
stool top 6.JPG
stool top 7.JPG
Russell Crawford
http://www.cherryleaf-rustle.com

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zeeway
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Re: Latest Stools

Post by zeeway »

My mouth drops open in admiration. Great looking jig work, and the fit on your Maloof joints is even better. Thanks for all the pictures.

Angie

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Re: Latest Stools

Post by armbrusterco »

Outstanding work on the jigs, fixturing and vacuum table! Thanks for sharing. I really like your latest system even though I thought your previous vacuum and fixturing system was fantastic.

I have admired your beautiful stools and chairs ever since you posted them.

Bob
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