Mobile Sewing Thread Storage Rack #1: Design


“Hey Ron, I have something you might want to build for me.” That was my wife speaking, and that’s how this project started. She does a lot of sewing. Awhile back, I made a Sewing Supplies Cabinet with Inlaid Metal Tile Accents to hold her sewing machine and various supplies. She stores her thread and bobbins in plastic boxes inside it.

She wanted a better way to store her spools of thread together with their corresponding bobbins. That way, if she wanted to use a particular thread, she wouldn’t need to search multiple cases. She wanted some sort of mobile rack, and she wanted it to fit in a small space (about 11” wide and 12” deep) between the cabinet and room corner. She wanted it to be attractive but somewhat unobtrusive so it would not compete with the cabinet.

The SketchUp rendering at the top of this post shows what we came up with (after several design iterations). It will hold 144 spool/bobbin pairs on tilt-out blocks in racks that swing open gull-wing style. With the racks open, she’ll be able to see her entire thread collection at once. 
The racks are mounted on a rolling cart. The cart’s base looks thick because it has a skirt around it that conceals the casters. The skirt has another potential purpose. I’m worried that the cart will be back-heavy and might tend to tip backwards. If needed, I can put some sort of counterweight inside the base to improve stability.

The storage blocks have shallow wells and dowels. A bobbin can sit in each well, with its matching spool on top. 

The spool blocks tilt outward. When vertical, the undersides of the spool blocks rest on narrow slats that also act as stops to keep the blocks from over-rotating when tilted. Small magnets in the blocks and tilt stops hold the blocks in their upright storage positions.

There are double racks on each side. They swing open, then unfold to enable access to the thread. 3/8” dowels and washers act as pivot hinges for the swing, and butt hinges enable the unfolding. 

The cart consists of a back/brace assembly and a base. The two assemblies are joined by screws up through the base into the bottom edges of the back panel and brace. That way, I can partially disassemble the cart to make adjustments if necessary. 

In case it's interesting to you, I thought it might be useful to present some initial (rejected) ideas so you can see how they evolved into the final design. 
Initially, I modeled a design with spools on either side of swing-out racks. The spools blocks were fixed at an angle. 

I also wondered about nesting the racks inside a case. They’d pull out, then rotate open. My wife didn’t care for this idea, so I went back to the original idea.

I thought about storing the spools upright and having them tilt out for access. 

I came up with what I thought was a clever idea—using carefully located rods that would act as stops. (I didn’t know how I’d keep the spool blocks from accidentally tilting out, though.) The rods would also help stabilize the tall, thin rack sides. 

The big problem with this design was what half the spools were facing backward, making it inconvenient to see and access the entire thread collection. The gull-wing doors were a response to that problem. The last refinement was changing the tilt stop rods to rectangular ones. 


Some serious planning in that design!

Lots of innovation (and lots of small parts), but it looks like it will fulfill it's duties for SWMBO
That's an impressive design effort! It will be fun to see this progress.
wow well thought out ron. she's gonna love having that.

working with my hands is a joy,it gives me a sense of fulfillment,somthing so many seek and so few find.-SAM MALOOF.

Thanks, guys. I’m almost finished building the thing. I am adding some weights inside the base, and I have some quality time with a hacksaw and some rebar ahead of me. Then it’s just a tweak on one of the pivot “hinges”, a bracket for holding the weights, and gluing on all the spool dowels, and I’ll be done.
You just started designing a few hours ago! 😀
Wow wow wow.  Great customized design! 
Very cool. I assume the weight in the bottom is to help keep it from tipping if they only open one side?  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.

Splint, what can I say? I had a productive morning. :-)

Thanks, Barb, Petey, and Lazyman. Barb, you’ll like my wife’s wood choice—walnut.

The weight will keep it from tilting backward when both sides are unfolded all the way. In that case, all the cart’s weight is in the back. The main problem is the inset casters. They make what’s already a small footprint even smaller, and the rear ones are a bit like a seesaw’s fulcrum. 
Walnut...always an excellent choice!
 “Hey Ron, I have something you might want to build for me.” 

Sound like she still loves ya.... and then she hates ya by demanding a imposing task,
 ..... so it would not compete with the cabinet.... 

Great use of SketchUp... if only the real unit will be that easy.
Just wait for the next "Honey do"... to learn the Dewey System for labeling/identifying each spool.

If your first cut is too short... Take the second cut from the longer end... LBD

That is a bunch of thread. But if that much is in play, then something like your design looks like it would work just fine. 
That's some impressive engineering, Ron.  I liked seeing the evolution of the design. 
Thanks, guys.

LBD, I do confess to hearing the theme to Mission Impossible in the back of my mind as I was starting to think about how to meet her requirements. :-) I'd have never finished this project without SketchUp. Not only did it let me iterate the design, but it also let me do manual interference checking. The rotate tool let me virtually tilt out the blocks to make sure they'd clear the spools below and virtually rotate the racks to make sure they'd really open.
Looks like a fun project!

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".