Wizcrafts

You are hijacking an old topic from 2018. The original poster has been inactive for almost a year. Rather than hijacking this old topic, you should start your own topic about the machine in question. Perhaps you will get some help then. List the machine or machines you need help with, and where you are located. You need to update your profile to show that you are in Korea. I am locking this topic now.

Oh, I see. My bad. I thought this was just a simple misadjustment of a machine. Your machine may need professional adjustment. Any further replies should go into your other thread about your machine.

I can show you how to further reduce the size or quality to get the photo withing our limits. But, I need to get some answers first. Are you using a hand-held device, or a computer? If a computer, is the operating system Microsoft Windows or something else? What app or program did you use to resize it? What is the size in pixels you got it down to (width x length)? What is the file size after reduction (in mb)? If you are running a Windows computer, I can explain how you can use the FastStone Photo Resizer to reduce the dimensions and quality.

Watch the video that Uwe posted earlier in this topic. It demonstrates the process to get the feet in sync with the needle and feed dog.

You have a long road ahead of you as a newbie to industrial sewing machines. You might want to start by searching Google for a military operations manual for the 97-10.

I have learned over the years of doing this that some people have to learn lessons the hard way. People keep reinventing the wheel!

I used to buy machines, parts and accessories from Neal and his Dad. GISM was very good to me when I was just getting into industrial sewing machines. If I was still on that side of the border they would be my go to dealer.

6.25:1

Exactly! That's the ratio when the motor feeds the large reducer pulley and the small reducer pulley feeds the machine. My Family Sew motors have very small 45 or 50 mm pulleys (~2 inches). The total reduction from the motor to the balance wheel on my cb4500 is 9:1. AT the slowest motor speed setting, with my foot feathering the pedal, I can watch grass grow as it sews.

I used to have a National walking foot machine that I installed a Sewpro 500GR on. I wish I hadn't sold it. The machine sewed all the way up to 7/16 inch using System 190 needles, or 3/8 inch with System 135x16. That motor with its built in reducer let me sew 1 stitch per second into veg or chrome tan leather with no help needed on the balance wheel. The reason there aren't many around is because the people who built them went on lunch break and never came back to work. ;-) Actually, they had an overheating problem due to the cases warping from the heat and torsion stresses. Rather than beef up the construction, they closed the factory.

Make sure you specify you want the smallest pulley they have for the motor. Some have a 45mm and others a 50mm small pulley. However, they typically have 70mm pulleys for high speeds in textile machines, as does the motor in the link you provided. It will be harder to sew slowly with that large pulley. Then compare that diameter to the pulley on your current motor. You'll need a shorter v-belt that matches to difference in whatever measurement you use.

Leather Machine Co Customer Service 866-962-9880

Here is the motor I use: https://www.tolindsewmach.com/motors.html

Number 207 thread is a fairly strong thread. I use it to sew suede lined rifle slings and guitar straps that total about 9 to 12 ounces. It can sew 8 ounces but it is a little tricky to hide the knots. These items don't place much strain on the thread; it just holds the layers together. Handgun holsters are a different matter. The edge stitching isn't just holding layers together. It has to hold the shaped or unshaped product together under the stress of drawing and holstering a steel weapon. You want the strongest thread holding it together. I use #277 to hold holsters together. It is possible to bury the knots in 1/4 inch of veg-tan if you play with the top and bottom tensions. I assume you are making pancake holsters if they are only 1/4 inch thick. Most of our holsters run between 3/8 and 3/4 inch thick at the outer edge. There is a filler between the layers that positions the weapon. This filler can vary from 1/4 inch to 1/2 inch. Your Cobra Class 4 is fully capable of sewing 3/4 inch thick holsters!

Your thread is too large for that thickness. Move down to #138 thread and a #23 needle. And, back off the foot pressure screw.

They don't bring as much because these were highly modified machines that are long out of production and spare parts and manuals are very hard, if not impossible to find. They will have some parts in common with their ancestors upon whose carcasses they were built.

My first impression is the the thread is too large for the thickness of the leather. You can verify this by telling us what sizes the thread and needle are, plus the combined thickness of the leather being sewn. When a new Cobra or Cowboy heavy stitcher is delivered to the customer, there should be a stack of leather 3/4 inch thick under the feet, or attached by trailing thread, sewn on that machine with #277 thread and a #25 leather point needle. It is your proof that the machine was properly setup and adjusted for thick work and thick thread. Aside from the needle and thread possibly being too big for that thickness, another explanation could be excessive foot pressure for that leather thickness. When you got the machine from the warehouse, the pressure screw would be screwed way down, far enough to hold down a 3/4 inch stack of leather sewn with a loaded #25 needle. If your two pieces are only 12 to 16 ounces, the pressure screw needs to be backed out considerably. It only needs to apply enough pressure to prevent the leather from lifting as the loaded needle ascends, which would cause skipped stitches. Any pressure beyond that will needlessly force the bottom leather to be impressed into the elongated slot in the feed dog. It also causes unnecessary foot tracks to happen on the top grain. The "pressure screw" is on top of the head, directly over the bar to which the outside presser foot is attached. It is known as the "presser bar."

@JRP430 - I moved your post to the Marketplace section where all ads for items for sale must be placed. This section is for old and used sewing machines.

We could probably shorten that clunky phrase to just Wizbit ! ;-) LULZ

If you do, tell Bob I sent you. LOL

Yes.

A 3:1 reducer will reduce your motor speed to 1/3rd whatever it is at the motor pulley. If your motor starts with a jerk at 100 rpm, it would start with a jerk at 33.33 rpm with the reducer. I've had motors like that and got rid of them, replacing them with Family Sew FS-550S servo motors with 2 inch pulleys and speed reducers.

You will be able to guesstimate how far the bar can be lowered by raising the feet with the hand lifter and handwheeling the machine. If the needle bar doesn't make contact with the feet, it can be lowered until it just misses the fully raised feet. If the manual states the distance, go with that measurement. Making sure you are using the correct needle system, install a new needle and fully seat it and check the timing. If the hook timing is still out, adjust the hook to intersect about 1/16" above the eye of the needle after it has risen 3/32" above BDC.

This makes two members in one week who mistakenly bought Pfaff 335 style binding machines thinking they were standard cylinder arm machines. I would advise you to post pictures and ask before buying a similar machine if you are looking at buying a used cylinder arm machine off some local ad, or auction site. If you see one advertised by a dealer, ask questions first. Binder machines are specifically built and equipped to sew edge binding onto material, like seat covers and sports gear and bags. They are not equipped to do "normal" sewing without changing out or adding some often times expensive parts. Off-brand machines may be even harder to change over if standard parts don't fit.

Yep, get a 2:1 or 3:1 speed reducer.