kgg

A couple of photo's of how your machine is setup on your table would help. If your short on space a suspended reducer pulley maybe a better solution then a box style speed reducer. With the suspended style you can install them either on top or underneath the table top.

My calculation for the top speed of the hand-wheel pulley should come in at 156 rpm using a 160 mm hand-wheel pulley size, a 50 mm motor pulley and with the motor speed set to the minimum speed of 500 rpm's. This particular servo motor is a 800 watt brushless 9 coil servo motor with a speed range of 500 to 5000 rpm's. So me being me I had measure the pulleys and hand-wheel to see how far off my calculations were. A) The constants: i) The hand-wheel pulley measured out to be 159mm. ii) The small pulley at the motor measured out at 49mm. iii) No speed reducer is installed. The results with 500 rpm's showing on the controller screen i) with the foot pedal fully depressed the rpm's with my digital tachometer showed 154.5 rpm's ii) with the foot pedal feathered to get the minimum hand-wheel pulley speed the digital tachometer showed a low rpm reading of 61 rpm's If I were to install a speed reducer (100 large pulley with a 50 mm pulley) I figure I could drop the max speed down to 77 rpms and the feathered speed down to around 24 rpms. kgg

What machine do you have, name and model number? kgg

My understanding is the Cobra Class 26 is a clone of the old Juki LS-341 so if you want a good manual download the manual for the Juki LS-341, Engineers manual. The Juki appears to rate their machines max thread size to the machines capabilities at max sewing capacity not by what size of thread can be stuffed through the max size needle. Juki LS-341 will take V207 thread yet the machine is only rated for V138 thread. You may have success with V207 thread for the top and bobbin thread in thinner material or V207 top thread with V138 bobbin thread in thicker items. kgg Juki_LS-341N_Engineers_Manual.pdf

You never mention how thick the items are that you are trying to sew. The 100/16 needle is really the bottom end for sewing with V69 in thin items or for V46 in thicker items. In thicker / tougher items move up to a size 19 or 20 needle. The problems to me sounds like the needle is being bent / deflected and with such a thin needle, size 16, it is going to be prone to breaking even with a tuned machine. kgg

Thank you. Dang I missed that one. kgg

Thank you. Those parts will fit any of the 441 class machines but hopefully make life a little more convenient. The cross brace from the right support leg across to the leg support leg is bend around the vertical support which should help. In this case I don't think drooping is going to be a problem as the downward weight of the machine is slightly off centered towards the front of the machines base. That should help to offset / reduce the amount of forward and downward torquing of the machine. When I remove the top horizontal section of the left support leg to remove about 6" the machine showed no signs of wanting to tip forward and downward. The top horizontal cross braces for all the legs were also lag bolted into the bottom of the table with four 1/4" x 1" lag bolts to the bottom side of the 1 1/2" table top. The top horizontal cross brace of the middle leg extends back to almost touching the mounting frame for the servo motor. kgg

Here is what has been done and I will be adding other accessories in the future for binding, etc. All comments are always appreciated. From what it looked like in the beginning to present. Note the drive belt beauty cover and needle positioner were placed just for the photo's and have been delegated to the darkest corner of the spare parts bin. 1) The table top cutout has been completed. i) The raw edge of the table top section that was cutout was trimmed off with metal edging, photo called Cutout.jpg, and Cutout 4.jpg . ii) The sharp metal corners have 3D printed trims to help soften the sharp 90 degree corner, photo called Cutout.jpg . iii) Two holes were drilled into the right side of the table top and two 3D printed thread guides installed to allow the top and bobbin spools of thread to be threaded through the table top. The reason for this was to allow for more usable space on the table top for other accessories and to allow for better thread relaxation / uncoiling, photo's Thread Spools.jpg and FrontALT.jpg. 2) The table metal support frame modifications are completed. i) The top horizontal overhang part of the left leg was cut back to the vertical support and reinstalled. I had to repaint this top section with the best match of paint I could find called "Sand" color, Front.jpg . This was my fault of allowing the cutoff blade to strike the vertical part of the support and grind into the paint / metal. When the top of the left leg was removed from the table so the machine was only supported by the center and right leg there was no problems of the machine, being nose heavy, wanting to tip forward. ii) I added an additional horizontal cross brace from the left leg to the right leg, FrontALT.jpg . This wasn't necessary but I had a 2" wide piece of 1/8" metal kicking around and it is cheap insurance. iii) The top and bobbin thread spool holder was installed on the right leg cross brace to allow for threading from underneath the table, Thread Spool.jpg and Thread Spool 2.jpg . 3) Machine convenience accessories have been 3D printed and installed on the machine with no drilling or tapping of holes in the machine. i) Snips and screwdriver holder installed to the front of the machine putting both in easy reach, Snips.jpg . ii) Bobbin and needle storage insert installed inside the wax pot to make better use of what would be a waste of space for me, Wax Pot.jpg . iii) Top and bobbin thread pin guide support installed. This support allows for a straight line from the top thread tensioner to the guide on the thread spool support. This also has a double bobbin holder incorporated to allow for a quick convenient place to store bobbins, Thread Pin.jpg .and Thread Pin 1.jpg .

The answer is yes. Some of the 29k's came with a domestic small foot pedal operated motor which cost about $30- 40 CAD but the mounting hole is in the casing on some models. I owned a 29K-71 which came from Landis and they had installed a geared domestic motor on it before being sold to the original owner. Speed can be an issue with the 29K's and clones as they are not really rated for anything over 500 rpm. You can see the motor on the rear side of the Singer 29K-71 in video https://odysee.com/@SingerSewing:0/singer:a The main purpose of that video is to demonstrate how effortless they should be able to be turned over by hand without anything under the presser foot. Another video with just a straight domestic motor installed on a 29k https://www.youtube.com/watch?v=qICJV7j56Gs Also here is another one be it of poor quality with a servo motor installed. https://www.youtube.com/watch?v=vMfzIcJ-spY The main question is are you trying to get torque for punching poor or just convenience of being able to use both hands? If I'm not mistaken the Eagle 550 is a 6 or 9 coil brushless motor. I think the motor has 6 coils but the sudden jump in my opinion is do to the motor having less coils. The 9 and 12 coil brushless don't seem to have this problem or not as noticeable. More internal motor coils means higher low speed torque with smoother speed control. Adding a speed reduce can really help mask the problem. kgg

Stay way from the cheap Chinese thread particularly in the 8 oz spool size. It can be a frustration generator. Buy a brand name sewing thread preferably one made in North America like A&E ( www.amefird.com ). Yes it will be more expensive but a quality products. Depends on what you are sewing. If the item is going to be exposed to a lot of UV rays or bleach bonded polyester would provide better protection then bonded nylon. Typically bonded polyester has a slightly lower breaking strength then bonded nylon for the same size of thread. You did mention "small holsters" the Cobra Class 26 can only handle up to V207 thread which maybe a little light for a holster. Some of the holster makers could address the best size of thread to use. kgg

@Handstitched, nicely done. kgg

The CB69000 / CB341/ 2750 / 4800 are clones of the Juki LS-1340 series machine, the main difference between the 1341 and 1342 (knob on top ) are: i) The knob on top of the LS-1342 allows you to change the vertical stroke of the presser foot and feed dog for going over thicker layers like a seam. That also regulates the speed of sewing based on the position of the knob. ii) The nose on the LS-1342 has a smaller gauge for doing tighter corners, smaller curves on smaller items. iii) The LS-1342 can sew 500 spm per minute faster then the LS-1341. All the other spec's are the same such as needle, thread and sewing thickness capacities. Another difference is that some clones rate the max thread size to what can be used by the max size needle the machine can handle where as Juki seems to rate their machines by what size of thread it can handle in it's max sewing thickness of material. kgg

The Cowboy CB6900 is a "down under" model. In North America they are called the CB341. The machine is a clone of the older Juki LS-341 so all parts for the Juki LS-341 and maybe the Juki LS-1341 will fit. As far as items like accessories if it will fit the Juki LS- 341 or LS-1341 it will fit the Cowboy CB6900 or the CB341. If you need to check for parts or spec's the Juki LS-341 manual is the go to manual. I personally think that all the clone machines should be labelled as to what they are copied after as it would make life a lot easier in finding parts. The Techsew 4800 is a clone of the Juki LS-1342 while their 2750 is a clone of the Juki LS-341. kgg

All bad enough but the floor is ceramic, that wouldn't go over very well. kgg

Yes you can use a 3D printer to do your molds, the cost of operation is very little at pennies a print to use. The major cost of operating a 3D printer is going to be the type and quality of filament you decide to purchase. Some people like the Enders I prefer the Prusa's but they are a lot more expensive. If you want very nice finishes I would suggest you go with a resin printer. Finding accurate files is going to be a chore as there are so many manufacturers and models available. Otherwise you need that particular model of gun and either 3D scan it or be very good with a micrometer and have some CAD skills. kgg

New location of top thread pin. Photo 1: Shows rear location and mounting of the 3D printed support for the thread pin. Photo 2: Shows the straight line to the thread spool top guides. Photo 3: Shows the clearance between my chubby hand on the hand-wheel in relation to the top and bobbin thread.

Thank you. I definitely agree, normally I do but in this case it was just a quick photo to show off the insert for the pot. The top thread pin now has been relocated further towards the hand-wheel mounted on a thread pin spool support I just 3D printed. The new location of the thread pin creates a straight line along the length of the machine from the thread spool guide to the guide on the pot. I will drop a photo later today. kgg

I can honestly see that happening with dogs and probably more so with cats deciding to have a nap there. I have one of those little magnetic LED lights plugged into the back of the servo motors on all my machines so when the motor power switch is in the "ON" position the LED light is also ON to remind me to turn the servo off. kgg

You are correct as the real Juki part number 210-64753 as listed in the parts manual list it as Oil Pot Assembly where as places like Campbell Randell list it as part number JUK-21064753 : Thread Wax Pot - Cast Oiler. I think the common reference to the pot as a wax pot is from olden days when beeswax was used in machines like Pearson and Landis. kgg

Thank you. The reason I'm keeping it on the machine is that the thread guide on top of the wax pot is directly inline with the guide for the top thread tension disc. I'm waiting for the 3D printer to finish off a new support for the top thread pin to keep the thread in a nice straight line along the top of the machine and inline with the wax pot guide. If I'm not mistaken most clone machines mount the thread spools parallel to the machine along the rear edge of the table top and then go directly from the thread spool guide to the top thread tensioner. Me being me I want as few angles so the thread is as close to a straight line as possible from the thread spool top guide to the tensioner. My spools of thread are going to be mounted under the table top so I can make better use of the table top for other things. I didn't get at cutting the table top today as I had to pickup a new 100 tooth blade. kgg

Nice job. kgg

As all as it works for your needs that's the main thing. I do appreciate the suggestion but my main consideration is the machine has to be topple proof because I have dogs and when they get rough housing I don't want them to be able to tip the machine from any direction. Odd need I know other wise I would have probably considered a pedestal style stand. As an update: i) The redneck bath and oiling is done. ii) I threaded some V207 on top and in the bobbin, stuffed 12.5 oz (5mm) of leather under the pressure foot and said it's make or break time. The photo (ko13.jpg) shows the first seam sewn with the machine, top (shiny side) and bottom. The photo (ko14.jpg) shows the bottom. I am surprised on how quiet it was as it sewed effortlessly through the leather and that was with a unknown brand of needle that came with the machine. The 800 watt brushless servo motor and machine is quieter then my KOBE LS-1341 with a 550watt brush motor. iii) The other photo (ko12.jpg) is showing the comparison between what I would consider a poorer quality bobbin and a good metal bobbin side by side. I'm actually impressed, so far. The servo motor showed no signs of struggling with what I was sewing and the speed is very controllable to control. I may not have to put a speed reducer on. iv) Made a wax pot insert. Since for my needs I can't see myself needing to fill the pot with any fluid so it is or should I say was a waste of space. It now holds two bobbins and some needles. Photo (ko15.jpg) shows the wax pot with the cover closed. Photo (ko16.jpg) shows the wax pot with the cover open and with a few needles and two bobbins inside. Photo (ko17.jpg) shows the wax pot insert sat on top of the cover. Next step is to cut the table top, maybe tomorrow and if my calculations are right the machine won't wind up going through the floor into the basement. kgg

Put it on toboggan and ride it down. kgg

Yes, the plan is to make a cutout under the cylinder arm but I'm slow. I'll get to that part after I complete the "redneck" bathing process. The first bath, a mixture of synthetic oils, now is complete and the presser foot lift pedal has been installed. Once the synthetic oiling is finished and the machine is running properly the next step will to remove three of the four bolts from the base, remove the drive belt and swing the machine 180 degrees so I can do the cutout. I really don't want to remove the machine from the table, it's to hard on the old back. kgg

For V69 the needle size should be a #18 or #19. The #22 would be for V138 in thin or V92 in thick material. A good reference chart for thread size to needle size can be had at: www.tolindsewmach.com/thread-chart.html You are going to have stitch alignment troubles should need to move the stitch in or out farther on the binding tape as someone welded the KH 90 degree raw edge binder to the bobbin cover plate. Getting this arrangement to work properly is always going to be a chore at best. You are now limited to that size of binding for that particular plate with the stitch in that location. Should you need or want to change binding tape size you are going to have to get a new plate and binder. Those 90 degree binders are expensive at about $90 CAD ($70 USD).