friquant

Go ahead. Buy a couple spools of TEX 270. Try it out on your machines. Experimentation is a great teacher.

You can do that too. In a different setup I have a 3-phase clutch motor being driven by VFD. Instead of running the motor at full speed (60Hz) I usually run it between 17-25 Hz. This means it's quieter and the pace is easier to manage.

See my post here: https://leatherworker.net/forum/topic/131403-my-first-vfd-w-3-phase-ac-gearmotor/ and blog entry here: https://leatherworker.net/forum/blogs/entry/518-option-d-3-phase-ac-gearmotor-with-vfd-variable-frequency-drive/ In the blog you'll see reference from other folks too. (I'm actually using an asynchronous (induction) motor, if I've got my terminology right) It's not actually a resistor...but yes the braking is quite effective. The braking settings on mine are confusing but I did get it to brake less than it used to 😃 Yes mine has maybe five options for ramp up speed. Would be better if the ramp-up was exponential instead of linear, but I'm being picky. Sewing at very slow speeds does not add any more energy to the coils than sewing at high speed. Yes the fan will spin slower, but there is also less heat going into the bearings because they are moving slowly. To even get the motor warm you will have to run it both at a considerable duty cycle and at considerable load. (At low load the motor doesn't slip much, meaning not much inductance, meaning not much heat generation.) When I'm sewing it's typically one minute or less of slow stitching followed by lots of minutes of figuring. My motor never feels warm...always feels room temperature. Adoption The biggest hurdle at the moment for the adoption of VFD is finding an inexpensive source for an AC induction gearmotor.

Heel tap functionality is typically done by rotating the lever on the hall sensor the other way. That is, the hall sensor lever is sprung in two directions...one for forward, the other for heel tap.

Definitely. Attaching here. The .stl file is probably what you need/want. The .f3d file is my original in Autodesk Fusion 360. The README is notes on printing it. By the way, the material I used is PETG. (It's tougher than PLA, and the creep issues are less than with PLA) pulley.f3d pulley.stl README.txt

That's great! Happy to hear What is your bobbin diameter? Did that hook come with your machine, or did you order it separately? My bobbins are diameter 25.7mm. There is enough take-up lever throw to accommodate a larger hook than mine has. Getting reverse stitch to match the same holes has some challenges on lots of machine. For one, there is no knob to turn...you loosen a screw then make your adjustment then tighten down. So it's hard to get a reliable small change in the direction you want. Beyond that, the feed dogs have a slant to them to optimize forward feeding. We can accommodate this for a particular material, material thickness, thread tension, stitch length, and presser foot tension. But then we change one of those variables and still hope that it matches up the holes in forward/reverse. I bought two binding attachments with the machine. I don't see how to attach them either. One of us could send a message to the Jianglong factory to ask. They usually reply with photos or videos.

As kgg mentioned, I've tried stitching with a sheet of copy paper under difficult materials. This made the stitching easier, but I had trouble removing all the bits of paper afterward. Perhaps something thinner that would dissolve in the water like tissue paper (the kind people wrap gifts in) or aluminum foil or wax paper or mineral oil or flour and water or cornmeal (ew!) or any of your favorite spices from the kitchen cabinet. Spitballing here, have not tried any of these 🙃

You may want to grind it to accommodate your desired thread. Here is a photo of my pfaff 545 when I got it. (note the ill-fitting bobbin case)

Found some reference to what this should oil in the user manual.

Where should I expect to see oil coming out at the left end of the main shaft? What does it feed oil to...the needle bar crank rod? Or the thread take-up crank shaft assembly? I expect there are some pieces that are to be oiled manually...just not sure which ones. This diagram shows the relevant pieces. Supposedly you rotate part #32 180 degrees to go from "minimum oil" to "maximum oil". Diagram is from page 3 of this juki ddl-8700 parst list: https://www.juki.co.jp/industrial_j/download_j/manual_j/ddl8700/menu/ddl8700/pdf/partslist.pdf

The "fiberglass" piece was removable. I pulled it out carefully. The jet was clogged, but shoving a sewing pin through it cleared the hole. In this photo we have: (left) Oil jet (middle) The clog. (silicone-like texture) (right) The "fiberglass" piece. (filter?) Am hoping that after reassembly (without the silicone-like clog) that it will weep a few oily tears for the hook.

Removed the hook This brass screw was screwed into the end of the hook shaft. The near end has a tiny hole in it, like a carburetor jet. The far end is not brass...rather looks more like fiberglass. Perhaps it is porous? After washing the brass screw in soap and water, I tried blowing through it. Nothing seemed to come out.

In the Stitchman Servo Motor: The Missing Manual Specifically this part:

What settings did you try for P-15 (Needle Detection Mode)?

I see now why you're asking if a needle positioner is required in order for that button to function.. What about the other menu functionality? Are you able to set forward/reverse and min/max speed?

What happens when you hold down the needle positioner button (far left) for 3 seconds, then release?

How to unclog the oil system on this cloned Juki DDL-8700? This is the first pumped sewing machine I've worked on. Machine has been sitting for about five years. Actual model number is FEIT DCL-8500N. Pump The oil pump appears intact. At low speed (200 rpm) it appeared to not pump at all, so I disconnected the vertical output pipe at the top and kept increasing the speed until around 1700rpm oil started spewing out the top of the vertical pipe. So there's at least oil now on the upper hook bevel gears. Splash Test But there's another tube that feeds the hook, and I'm not seeing any evidence of oil near the hook yet. In this video the man does a splash test with a paper towel to check how much oil is reaching the hook: https://www.youtube.com/watch?v=hQCUZs1-vUY&t=163s Here is my paper towel, still dry: Valves I have opened the valve that regulates oil to the hook: and also opened the valve that regulates the oil to the needle bar crank assembly: but still not seeing any on the hook or on the needle bar crank assembly. Tthe user manual says that when machine is new or anytime after it's been sitting idle for a long while to run the machine at 3000rpm for a period of 10 minutes. So far I've run the head unit a couple minutes at 2400rpm (checked with tach). I want to see evidence of oil flowing before I run it enough that it really needs oil, if you catch my 22. Filter? Earlier in this same video the man cleans out the filter in the pipe behind the hook: https://www.youtube.com/watch?v=hQCUZs1-vUY&t=59s so perhaps that will be my next move. As for the needle bar crank, I'm not sure sure what to disassemble to clear the way. Water Worth noting perhaps that I did find evidence of water in this machine. The oil pan drain plug is rusted in place and I did not manage to free it. Not even with mild application of a kitchen torch, a few hours soaking in diesel, and an impact driver. 🤷‍♀️ Also the old oil looked milky. And in part of the presser bar I found a couple drops of water concealed within some drops of oil. But I don't really expect water in the past to clog the oil pathways Manual I'm using this as a manual: https://www.juki.co.jp/industrial_j/download_j/manual_j/ddl8700/menu/ddl8700/pdf/instruction_eg.pdf

I'm not sure. I've seen two different sized 4-pin connectors used for needle positioners. Have not tried mixing and matching.

No, this is not typical from the 3-4 models I've used. Are you able to view the other settings? Can you upload the user manual that came with the motors? Is there a 4-pin connector on the back of the controller to accept a needle positioner?

It was very handy to be able to adjust it in increments. I had been breaking needles attempting to stitch through a 1/2" (12mm) stack of vinyl and foam (auto upholstery project). So I disconnected the belt and ran a few stitches by hand on a thick test piece and it wasn't very many stitches by hand before the hook point tried to bisect the needle. Ah-ha! After that discovered the needle guard adjustment screw, put some medium strength thread-locker on it, and backed the set screw out until the needle guard mostly prevented contrived collisions of the same sort. Then put it back together and stitched that troublesome seam in one pass (relief!). Not seeing any skipped stitches or unraveled thread yet (If I did I would think I had gone too far with the adjustment.)

I hadn't noticed this before, but I think it's an adjustment screw for the needle guard. (Jianglong 341) Looking closely, I could see a hexagonal shape behind the round hole. 1/16" (1.7mm) hex wrench seems to fit. Or from a different angle: Here I removed the needle guard and you can see the set screw that sits behind it: I've been wanting the needle guard to be stiffer anyway. (What good is a needle guard that just gets out of the way when the needle comes by?) Using this adjustment screw will mean there is a support closer to the bulge in the needle guard, so I expect it to flex less when the needle presses against it.

Oh that jogs a memory. I've got a deal in the works to buy this machine that has two foot pedals. It might be for raising the presser foot though 🤷‍♀️

A bag maker in the making...with a zypper, no less 🌟 That seam next to the zypper would look cleaner if you pull the old thread off. (Looks like you made a seam, ripped that seam out, but left the old thread)

Sounds like a video in the making 😉

I'd like to see that. She appears to be using a clutch motor, based on the rapid start / rapid stop and the old style ON/OFF power selector.