friquant

How to buy or make a finger guard for a Juki 341 clone? I occasionally see photos of triple feed machines with finger guards, but the feet I bought do not have extra mounting holes for guards.

I've decided to give up on this quest for now. Putting the machine back together and time to get to building something. 🚶‍♀️

Is this to drive the machine or to lift the presser foot? I thought you were going to use the kick drum lever to tell a separate servo to raise the presser foot.

Ooooohhh... Can you post links to the servo you're using for this?

Beautiful table! A foot lift is activated by pressing down with your foot, a knee lift is activated by pressing to the right with your right knee. My Jiang Long came with both, but I had to ask how to install the knee lift. Here is the install video they sent me...the chain actuator reminded me of your singer. 937adbfd78d59f2d56efebcd9d6f1892.mp4

I'm in search of the perfect hundred-dollar servo motor. I've had two motors, both of them good but neither perfect. Here are some requirements that would make me happy: Distance in degrees between needle-up and needle-down should be configurable Motor should use standard 15mm cylindrical shaft with key hole, since a range of aftermarket pulleys are available for this shaft size There should be a long range of travel in the foot pedal between slow and fast The maximum speed should be configurable When the maximum speed is set to something slow such as "900 rpm", the range of pedal travel should be spread across the entire usable range. Meaning you should have to push the pedal all the way to get to 900rpm if 900 rpm is your max. Slow start, ideally, would be a gradual transition up from 0 rpm into some minimum speed. (The slow start I have used before still immediately jumped from 0rpm to 200 rpm, which was not gradual at all) When you tap the gas pedal to ask for one stitch, you should ALWAYS ALWAYS ALWAYS get exactly one stitch. If you give two stitches instead of one now there's an extra hole in the leather that I hadn't planned on. Also, giving more stitches than asked seems like a safety issue. When you heel-tap to ask for the needle to come up, the needle should come up. It must not do a full turn and then come up. That also puts unwanted holes in the leather and seems like a safety issue. The power switch must be in easy reach of the operator The power switch should light up so we can see when it's powered on When the power switch is turned off, the motor should immediately stop. (Safety) Pressing the gas pedal after the power switch has been turned off should have no effect. (Safety) Instructions for operating the manual should be provided in clear language. (I'd be happy to help you write the instruction manual) Ideally one could limit the amount of torque through the control settings There should be no settings visible in the menus that don't do anything. The settings in the menu should be numbered incrementally. No skipping numbers, as this is confusing. Ideally, needle position sensor would stop within one degree each time. Five degrees may be acceptable, but one would be better. If the gas pedal is pressed down while the power button is turned on, the motor should not start. (Safety) Rather, the motor should wait until the gas pedal is released and then pressed anew before motor starting. Ideally, the minimum speed would be 30rpm. This would alleviate the need for a gear reducer for many people. Though if small pulleys are available, 60rpm may be fine. The factory default maximum speed should be something medium slow like 1000rpm. Let the user increase it through the menu if they need it faster. If the belt slips such that the motor has to turn farther than it expected for the needle position sensor to register one complete cycle, the motor should stay in needle detection mode. Ideally, the needle position sensor should have an LED that lights up when the positioner is in the needle-down position. (Makes for easier setup) Assuming this unit comes with a needle position sensor, the controller should have needle positioning enabled by default.

Attaching pages 12 and 13 of the juki 1541 manual. After you adjust section 9 (horizontal feed cam timing), you will have adjusted it so that in a certain position, you can rock the reverse lever back and forth and the feed dog does not move. This is the position you will want to initiate your reverse stitches from. On a machine with a needle position sensor, you can set the position sensor to always stop at approximately that position. Needle positioner or not, I find it useful to have some clear markings on the machine and handwheel showing you when you are in this "reverse magic" position. Here's a picture of my alignment marks in blue tape.

Here is the geometry of the throat plate.

Repositioned the throat plate so that it aligns better with the overall shape of the cylinder bed, and adjusted the feed dog and needle positions to match. The thread now enters the latch cleanly about 60% of the time (Reverse, max stitch length), but the thread is no longer riding in the shoulder. (So many compromises!) The camera angle is different this time. I tried to get a directly top-down view (as close to orthographic as possible) to show the relative angles of things. The bobbin case is not square with the throat plate. I'm not sure if this is how it should be. I'm thinking on how I can test with different throat plate geometry to see if I can get the best of both worlds (thread riding in shoulder, with clean thread entry into latch) attempt-2__small.mp4

When I was learning to drive an industrial sewing machine, my favorite thing to practice on was actually corrugated cardboard. Ubiquitous, cheap, thick, stiff. You can cut two pieces and stitch them together. Or you can just stitch on one and make a pattern. At one point I was drawing curvy lines (with some tight corners and some loose corners) on the cardboard first, then seeing how well I could follow the line of ink. For practice, I enjoy having a different color top thread than bobbin thread. That makes it easy to see tension discrepancies.

Sounds frustrating. Here are some things to try: Does the machine turn over freely when bobbin and bobbin case cap are removed? (Can turn handwheel a couple revolutions to check no binding) With bobbin case cap in your hand, and the bobbin loaded into it, does pulling on the thread show smooth, even tension? With bobbin case and bobbin installed in machine, but no fabric under presser foot, does pulling on the bobbin thread show smooth, even tension?

Appreciate you chiming in to confirm. 😀 The edge of this shoulder is sharp, so it makes that we want the thread nestled inside the shoulder groove instead of dragging across its sharp edge. Originally (when I took the photos for the beginning of this thread), the feed dog movement was nicely centered in the opening front to back. Shifting it to the rear (away from the user) seems to make it so the thread almost always rides inside the shoulder groove. It's still very clunky though stitching in reverse at 4mm or longer stitch lengths. I'll do my best.. (Hats off to the videographers of the world that make it look easy!) Hopefully this will help to debug. I do love the sound and feel of a machine when it sews smoothly, and it seems I'll never get back to stitching until I unravel this mystery. hook-1-overall-export__small.mp4

In my original post, I reported that after setting the hook-to-needle distance to factory spec it was stitching fine in reverse. Well it's true that the hook is no longer bisecting thread. But it is quite clunky-sounding in reverse with long stitches. Here is a video that shows where it's still hanging up. 😢 This is stitching in reverse at max stitch length. 19-options-36.mp4

@MML Glad to hear the needle positioner is working for others too! I added a reply to the manual that shows how to access the hidden menus. The most useful piece so far is being able to set the upper bound on max speed. 🐎😀

Hidden / Admin Menus After making the original post, I found a video on how to access the hidden/admin menus. To view/edit the hidden menus: 1. Hold P while press "-" 2. Enter number "2013" by pressing "+" "+" "P" "P" "+" "P" "+" "+" "+" 3. Save by pressing "S" 4. Now you are in programming mode with hidden menus enabled Thank you to youtube's @kuchkosol126 who made this youtube video for showing us the hidden menus: https://www.youtube.com/watch?v=Ksw97IGThsg (admin) P-01 (Upper bound on Maximum Speed) This limits how high the user can set their maximum speed Useful!! (admin) P-07 (unknown) default: 1100 range: 800-2000 (admin) P-08 (unknown) default: 0 range: 0-1 (admin) P-09 (uknown) default: 0 range: 0-1 (admin) P-13 (Strange things) When I enabled P-13 the motor would rotate in reverse direction for a quarter stitch, then quickly go forward again. default: 0 range: 0-1 (admin) P-14 (max current) default: 0300 range: 050 - 1000 (I suspect this is non-functional I tried setting this to 050 but my the pulley still slips for me instead of the motor limiting the torque) ### (admin) P-17 (unknown) default: 1 range: 1-3 (admin) P-18 (Set Admin Password) This allows you to change the admin password default: 2013 Thank you to youtube's @kuchkosol126 who made this youtube video for showing us how to set the admin password https://www.youtube.com/watch?v=hrwzXAHG6qc

When a hook has a shoulder, does the thread need to ride in it? The hook on my JiangLong 341 (clone of Juki 341N) has a shoulder to it. When stitching forward, the thread rides in this shoulder. (See the first two photos) When doing long stitches in reverse, the shoulder did not catch the thread so the thread is lagging behind the shoulder. (See last two photos) The reason I am investigating this is to understand how the machine is so noisy when stitching long stitches in reverse. I have set the hook-to-needle timing and the hook-to-needle distance according to the juki manual. I have tried different positions of the latch opener. The latch opens the gate, but the thread does not go through it while it has the chance. Later, the thread gets yanked past the gate....yeek!

By the way, I went looking for a manual for this machine, and I found this one which unfortunately is in several languages: https://www.juki.co.jp/industrial_j/download_j/manual_j/du1181n/menu/pdf/instruction_7K.pdf#page=1 Page 36 begins the section on ratio of movement between the two walking feet

I'm attaching a photo of my machine that has adjustment screws "A" and "B" labeled. "A" adjusts the amount of overall lift (to be shared between the two pressers). "B" adjusts the needle-to-inner-toe timing, and at the same time is what you adjust to achieve equal (or unequal) lifting heights between the two pressers. I'm assuming you loosened "A", raised the arm in the slot, then tightened back up. This is what you would do to be able to walk over bigger humps. (Sometimes I need this set to max to be able step down off of a hump too, or else the back of the outer toe hangs up.) To see how to adjust "B" for equal walking heights, see Uwe's video. In his video he sets it for equal lift height. If you set the lift height slightly UNequal, your needle will land just before or just after the inner toe. You can experiment.

Unread notifications show up under the bell icon in a different color, this is good! But as soon as I click one of those unread notifications, ALL of the unreads change to the color meaning "already read". It would be great if clicking a single notification only marked that item as read, instead of marking them all as read. Don't know how much of a lift that is on the backend..

This thread has been quite the fun read, with good pics

Dahlicious! Especially like the framing of one material (rattlesnake?) within another.

The single thumb screw sounds great! My plexiglass table I still need to do some filing on to get it to sit completely flush. But now I know what to do if I file too far...Steel Stik 😺

I did find discussion about that later in a different post. Guess I'll start practicing my "That's Cool! "

Would like to be able to react to forum posts (and replies) that I read with an emoji. I could add a message to the thread, but I don't want to clutter the thread if only to say "This is cool"

Lift Which piece did you adjust to achieve greater center toe lift? I typically raise the lift of both pressers together, meaning if I have lots of humps to jump I put the lift at its max (with equal lift per presser). Tension In my experience, thicker fabric requires more top tension. So to have no loops, you would need enough tension to match the thickest section of your seam. It's odd that yours is mostly looping only on the transition from thin to thick. If I'm counting your folds correctly, your thickest section is nine layers of denim. I would set up a test piece so you can do an entire seam through nine layers, and use that test piece to sort out needle size and top tension. Give just enough tension to hide the bottom knots on the thick test piece, then go back and see how those same settings do on your standard piece with the thick / thin transitions.