Quilting Frame

Inspired by the 3 MPCNC machines I’ve built, I designed this quilting frame for my wife. The trucks are similar to the bearing blocks of the V1 machines, and uses the same electrical conduit rail system.

This is the first prototype, and I’m printing parts now to see how well the design will work. It’s basically a CNC machine for sewing, except the motion is typically controlled by hand. The sewing machine sits on the platform, and will have handles for control. A separate frame (not shown) holds the quilt.

It could be computer controlled, but the utility is limited by the throat size of the machine, so it has a relatively small space to operate. A huge feature is to add encoders that roll on each axis, and control the needle speed based on the linear speed of the platform.

It’s based, in function, on the commercial products Cutie style quilting frames and the SureStich regulator.

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Sweet, keep sharing the progress, this is a pretty interesting use of conduit and 3D printed parts.

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I’d be interested to see how you integrate the rotary encoders!

My wife has a 12 foot long arm frame and standard sewing machine with a 12 inch throat, but the main thing holding her back from using it is no stitch regulation, so whilst she has a hand controller to stop/start and change the speed, if she stops for a second to reposition you always end up with a knotting of thread while you try and stop it.

If you add the encoders, I’d love to see what you use and how you add it, as being able to apply that to her machine would give me so many CNC time credits I’d be in heaven :stuck_out_tongue:

This sounds like a good machine to retrofit. I’m looking into turning the stich regulator into a stand-alone product to offer a better and lower cost solution to the current commercial offerings. I think the stich regulator is an absolute must.

The backside of my rail system looks like this.

And the current encoder mounting looks like this.

The lower rail is the side-to-side axis. The encoder is clamped to the upper rail that moves. There’s a short arm that the encoder is mounted on and pivots on the screw holding the clamp. It rides on the lower rail with gravity pressure, and I added some rubber bands around the axel to provide some additional friction.

This “works” but is not ideal. It does seem to roll ok, but there’s not much contact area so I expect cord management and misalignments to make this unreliable. Also, there isn’t enough clearance in the upper platform to do this gravity pivot trick so I can’t use one solution for both axes.

What I’m planning on doing is using a timing belt in the same way that the V1 machines do for the steppers. This approach should be very reliable, and also allow a stepper to use the same belt for a gcode driven machine.

On the firmware side, I have an RP2040 microcontroller with a circular touch screen. This reads the encoders, computes the linear speed of the machine, and drive a digital potentiometer connected to the machine.

The microcontroller can calibrate itself to the machine using an optical switch and a piece of paper taped to the needle to characterize the “throttle” position to the needle speed. Given all of that, it should be able to very accurately calibrate the stitch width.

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Here’s the first video demonstrating microcontroller control of the stich speed.

This is just a proof of concept to demonstrate viability. There’s an encoder on each axis and the microcontroller reads position, computes speed, and drives the pedal input to the machine.

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This is amazing. I am clueless about all the ways this related to sewing / quilting, but it is amazing.

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Very cool!

I’ve been putting some thought into an embroidery machine, it could very much use a similar mechanism to control the sewing machine. Will be watching with interest.

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Is this intended to perform similar to a longarm machine? That is really cool, but It will be very interesting to see how you solve the whatchyamacallits around the bobbin that drag the fabric. Is it important for those to move in line with the foot and stitch? Are you thinking the whole head would rotate?

It’s entirely possible I misunderstand what this machine does. That proof of concept is cool though.

The Feed Dogs.

Yes, it’s similar to a longarm machine. The only real difference in the machine is the “long” part which is the distance between the needle and the body of the machine. This is a mechanical limitation of the machine, which limits your front to back movement before you have to reset the fabric.

For free motion quilting you drop the feed dogs so they do not move the fabric. You also use a different “foot” that allows the fabric to move freely and gives clear line-of-sight. The fabric will roll up in the space between the needle and the machine.

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Continuing this project, I’ve designed a circuit board for the brains of the project. This cleans up the product nicely. Encoders plug into the RJ11 jacks, machine plugs into the 3.5mm jacks. This board mates to a touch screen LCD for the user interface.

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