Tips For Your 441 Sewing Machines (Courtesy Of Cobra Steve)

[Johanna]

MAINTENANCE AND TIPS FOR THE COBRA CLASS 3, 4, & KING COBRA,

PRO 2000, ARTISAN TORO 3000, 3200,4000, Cowboy 3500, 4500,

TECHSEW 5100, SEW PRO 44L, KINGMAX, MASTER LOCK, JUKI 441. AND

OTHER 441 STYLE MACHINES

Thread

1) Make sure that the thread you are using is not dry, old, or damaged by the elements.

Keep thread in a plastic bag to help protect it.

Make sure that the thread does not untwist, if so, then the bonding agents have

evaporated or weren't very good to begin with.

Threading

2l Make sure that your machine is threaded correctly. Breaking thread, skipping, fraying

the thread, and tension problems will occur if your machine is threaded incorrectly.

Take up lever

3) The take up lever has 2 functions: to give the thread enough slack so the hook can carry

the thread around the bobbin case, and, after the hook releases the thread, allows the

thread to pull up into the leather.

Check spring

4) The check spring maintains tension on the thread as the take up lever returns to the top

position.

Needles

5) The needle must be installed correctly. Make sure that the long groove is on the left,

and the scarf is on the right.

Needles are tempered, so after usage, they lose their temper and become weak. A weak

needle will bend or break easier after losing its temper. When the needle breaks, it

could cause damage to the presser foot, needle plate, feed dog, or shuttle hook, so

make sure that you change your needle every 12 hours of actual sewing.

Also, make sure that you use the correct size needle for the thread and thickness of

leather that you are using. lf you are using too big of a needle, then at times, the thread

will travel up and down inside the hole that the needle punched resembling a tension

problem. lt is all relative. The heavier the leather, the heavier the needle and thread.

The lighter the leather, the lighter the needle and thread.

Tensions

6) The thickness of the leather that you are sewing will dictate the amount of tension that

you will need. You should loosen the tensions for lighter leather.

Your tensions work in conjunction with each other, so you should loosen or tighten both

tensions when adjusting them. You should never loosen or tighten more than 1 full turn

at a time.

lf you run into a problem with your tension and you are not sure which way to turn or

you just can't seem to get your tension back where they were, then it is time to recalibrate

them. This is a simple task.

To re-calibrate your tensions, remove both knurled tension nuts completely, then put

them both back on the machine until they just come in contact with the tension spring

and stop. Sew a test piece. You will probably find that the stitch is toose, but this is what

we want. You are now able to adjust your tension by tightening them both 1 turn at a

time untilthe stitch pulls up.

You may also experience bobbin tension problems. lf you have tightened the bobbin

tension as far as you can, and stillthere is not enough tension (the bobbin thread is

visible on top of the leather), you may have to clean out under the bobbin case spring.

After hundreds of yards of thread pass under the bobbin case spring, microscopic fibers

of thread, along with leather dust and other debris, start to collect under the bobbin

case spring causing the spring to spread and give false tension.

lf this is the case, then you will have to remove the spring, clean out the debris, and may

have to bend the spring to put more pressure on the thread which will give you more

tension and allow you to be able to adjust your bobbin tension as well. You may have to

purchase a new bobbin case spring if re-shaping your existing spring does not work.

Shuttle Hook

7) lt is very important that your shuttle hook is in excellent condition. lf your hook has

burrs, or scratches, then you must buffthem offto make your hook smooth again so the

thread will pass over the hook with ease. lf your thread is fraying, then a burr is most

likely the problem. The thread will pass over the burr and then get caught, causing a

couple of the strands to break. You should run your finger nail over the top, sides,

under, and at the point of the hook when feeling for burrs.

The shuttle hook travels in the race assembly. You should clean out the race assembly

frequently. The race assembly must be clean, smooth, and oiled to assure the best

sewing results.

Needle Deflector

8) The needle deflector is located in the shuttle hook area. lt actually deflects the needle to

protect the point of the hook. The needle will brush against the deflector moving the

needle slightly to the left of the point of the hook. lt also keeps the needle straight,

assuring that the loop made by the thread is consistent.

Presser Feet Timing

9) Both Presser Feet should rise to the same height as they alternate walking. The

procedure to assure that your presser feet are walking correctly is to turn the hand

wheel towards you until the point of the needle is even with the plate or feed dog. At

this time both presser feet should be down. The needle, and both presser feet should

meet at the plate or feed dog at the same time. lf this is not the case, then loosen the

adjusting screw and make the adjustment. The adjusting screw is located on the far right

side on the back of the machine. lt is an Allen Head screw.

Presser Feet Height

10)The presser feet height is determined by what you are sewing. For the most part, the

height is set at medium to high. This will allow most applications to feed (whether thick

or thin) without getting caught on the feet and impeding the motion of the feed system.

lf you are manufacturing one item, like belts, where the thickness is constant, then you

would set the height to accommodate the belts thickness. This adjustment is in the back

of the machine, and is sometimes referred to as the "banana slide" adjustment.

Hook Timing

11)To set the timing for the hook, first remove the needle plate and in some cases, the feed

dog. This will allow you maximum vision. Set the stitch length to zero. Put a new needle

in the machine. Raise the presser feet to the up position. Turn the hand wheel towards

you untilthe needle is in the lowest position. Continue to turn the hand wheel untilthe

needle comes up 3/16" , this measurement is critical. At this time, the point of the hook

should be even with the needle and approximately 1/8" above the eye of the needle,

and in the scarf of the needle as well.

To adjust the shuttle hook, remove the round cover plate on the front of the machine

located in the lower right hand side. After removing the cover plate, look inside the

machine and you will find the black Allen Head bolt that holds the hook driving shaft.

You may have to turn the hand wheel to get a better view of this bolt.

Loosen the bolt and you will be able to physically turn the shuttle hook while it is in the

machine. Turn the shuttle hook to the correct setting, 1/8" above the eye and then

tighten the bolt.

This may take more than one try.

Tip: A quick way to check if your machine is out of time is to lower the needle. Just

above the screw that holds the needle in place, is a hole that you can look into and see

the top of the needle. Loosen the screw, then drop the needle until it covers half of the

hole and try sewing. lf the machine sews properly, then you will have to advance the

shuttle hook about 1/32" .lf it still does not work, the lower the needle again, until the

top of the needle is even with the bottom of the hole, and then try again. lf this corrects

the problem then you will have to advance the shuttle hook about 1/16".

lf your machine still does not sew properly, then retime your machine based on the

instructions above.

These adjustments may vary depending on the machine. These instructions offered in

this tutorial may not be absolute, because there are other factors that could come into

play, but are a good starting point.

Thank you, Steve

For more info, please call:

Leather Machine Co., lnc.

1-866-962-9880

[DoubleC]

Thanks Steve. Cheryl

[Techsew Ron]

Great tips!

Here's a threading video you can all use:

[Ian1783]

Great tips for general knowledge, not just the focus on the machines mentioned. I learned, or had reinforced, a few steps in the process.

One query: I see in Ron's video (great video) the double looping of the thread around the upper tension disks. I've run across this before, but can't recall if it was for a specific machine of mine, or a threading step for any number of machines. Can anyone describe why the double looping, and if it pertains generally to a machine type, or more specifically to a make, model, class, etc.?

Ian

SF Bay Area

http://imcinnis.blogspot.com/

[Red Cent]

In the video, the fellow went through the eyelet and over the disc and straight down to the next eyelet. He did not go around the disc and back out of the eyelet as they suggest on a Cobra 4. Other than the "L'" arm protruding between the side discs and the check spring everything else is Cobra 4 threading.

I am beginning to believe that each machine has a myriad of combinations that will work. If you go to You Tube and watch the threading proceedures on each machine, they are different but they supply the "correct" tension for the machine.

The following represents success on one piece of leather but:

On my Cobra 4, I came from the spool to a lube pot on the top of the machine to the eyelet on top. Through the eyelet and straight down ( not around the disc but snapping the thread between the discs) to the the side eyelet. From there I took the thread counterclockwise until I was level with the check spring (not twice around) through which I threaded. Then up to the take up arm, down to the (can't remember the name) then as Cobra 4s are supposed to be.

Between this "mod" and changing from nylon to polyester, I did not have any skipped stitches nor did I have any of the signs of bad tension. It also rid me of past problems of the Cobra 4 "seizing" the thread and causing thread problems. One, when it did grab, the top thread would lie straight in the stitch groove and the bobbin thead would show on top.

I will try to remember to report back. I cut and glued two holsters tonight and tomorrow I will sew. Please pray for me.

Edited September 1, 2013 by Red Cent

[SteelcityK9Cop]

Should be a sticky.

[Handstitched]

G'day Red Cent & Ian1783,

I have a Q Stitch Colt, which is vertually identical to the Techsew 5100 in the vid. with only a slight difference on the thread guides.

On my machine, I loop the thread though the eyelet through the (top) discs , give it a slight tug to make sure it 'sits in' ( sometimes hearing a slight 'snap' of the discs ) , and back through the eyelet , and continue threading.

Before I did that, on some very rare occasions, the thread 'snapped out' of the (top) discs whilst sewing.

This threading method rectified that little problem.

Also, as we all know, oiling your machine/s at regular intervals is important .

As well as oiling all the regular oiling points on my machine, I take the shuttle hook assembly right out and put a little bit of oil on the rounded part of the assembly. ( and anything else on the machine while its out), but not too much .

Just a little thing that I've learnt from my own experience.

It now runs whisper quiet.

All the best,

Handstitched

[Anne Bonnys Locker]

Most of these tips are relevant to the Highlead machines but with the extra precaution that if the needle bar assembly has any sideways movement you need to remove the faceplate and undo the screw that holds the small bracket in place. Push the bracket against the needle bar assembly and tighten the screw. This will save lots of ongoing problems.

[chapman]

Hi i'm new to all of this posting stuff so please bear with me a little . i just recieved a new cobra 4 from Steve and i'm wondering if i should sell my old consew 226r1 for the lighter materials. can anyone tell me how light of a material can i sew with my new machine?? i'm just getting my new xmas present from my lovely wife set up and i put it oncraigs list but i'm wondering if i'm making a mistake letting go ot it??? Thanks in advance for any advice you guys can give a noobie..... Chapman..

[lws380]

Hi i'm new to all of this posting stuff so please bear with me a little . i just recieved a new cobra 4 from Steve and i'm wondering if i should sell my old consew 226r1 for the lighter materials. can anyone tell me how light of a material can i sew with my new machine?? i'm just getting my new xmas present from my lovely wife set up and i put it oncraigs list but i'm wondering if i'm making a mistake letting go ot it??? Thanks in advance for any advice you guys can give a noobie..... Chapman..

I would suggest keeping it if you want to do thin stuff. I don't try to sew thinner than 5-6 ounce total thickness on my Cobra 4. I actually bought a Cobra 18 to do thinner stuff and it works better for thinner leather. Unless you need the money, why not wait a little bit to see if you need the Consew for thinner stuff if the Cobra won't work? You can sell it later if the Cobra does all you need.