Singer 29K 71 Patcher / Cobbler Upgrades

[kgg]

I have made some 3D printed upgrades to my 1949 Singer 29k-71 which can be used on other versions of the Singer 29K as well as other machines like the Consew 29, Cowboy CB29, Cobra 29, Techsew 2900 to name a few.

The upgrade requirements: i) Simple ii) No holes to be drilled or tapped into either the sewing machine or the cobbler base. iii) Installed / removed in under 5 minutes with no special tools.

1) Photo 6 is a view from the pulley wheel side showing a Double 1 pound spool thread stand and threading rod holder mounted to the cobblers base (Photo 5). The top thread stand guides can be positioned and locked in place as needed. The height from the cobbler base to the thread guide holes is 2 and 3/8 the height of the thread spools.

The threads then leaves the thread stand guides and goes to another double thread guide to keep the threads separated and keep the thread angle down.

This double thread guide replaced the original 4 oz spool pin. Both threads then go to under the lever in the oil pot and exit through the two holes in the end of the oil pot. The inside thread then carries on as the top thread to the top thread tensioner and to the needle. the outside thread carries on to the darning tensioner to be utilized for the bobbin thread. All the instructions I have read or viewed for winding a bobbin either with the hand wheel on the front or the side want you to wrap the thread around the bobbin and guide the thread onto the bobbin. Which to me seemed OK but there had to be a better way that gave a more consistent winding of the thread onto the bobbin and allowed me to wind a bobbin while sewing.

To accomplish this I used the Darning Tensioner was used to give consistent, adjustable tension as I don't darn and haven't really figured out what the advantage it would provide over the top Thread Tension for darning.

If someone can explain this I would really like to know as I can't seemed to find any information in the 29K manuals.

The next step was to make a guide that would replicate my fingers position and properly guide it onto the bobbin (Photo 4). The guide when not in use folds back against the machine. For those that use the hand wheel mounted to the main drive shaft I do have a simple design just haven't 3D printed it yet.

2) Photo 3 is a view from the front showing the top thread path to the head and the bobbin thread path to the bobbin being threaded.

All comments greatly appreciated.

kgg

 

[MtlBiker]

Very nice!  There's something very cool about using such modern technology (3D printer) to make accessories for such a classic, dare I say, "antique", machine.    You're certainly very creative and skilled at making things.

Never having seen one of those machines before, I might not appreciate how your thread stands improved the original.  For someone like me (newbie) does that machine not have a bobbin like most machines?  Does the bottom thread feed through the machine directly from one of your large spools?  From the photos the thread looks very thick... what is it?  And you're using the machine via the hand wheel without a motor, right?  Does that not make it more challenging to hold your material assembly in place with one hand?

You refer to photos 5 and 6, but there are only 4 photos in your post. 

 

[Wizcrafts]

1 hour ago, MtlBiker said:

For someone like me (newbie) does that machine not have a bobbin like most machines?  Does the bottom thread feed through the machine directly from one of your large spools?

The Singer (and Adler and Claes) patchers are all lockstitch machines with bobbins. The bottom thread is feeding the bobbin winder, which winds fresh bobbin loads, not the bobbin in use. That bobbin lives in the left end of the cylinder arm, just to the right of the needle and is inside an oscillating shuttle that picks off the top thread loop formed by the needle making a down>up>down jog. The bobbins are extremely tiny and aren't normally threaded with anything larger than #92 bonded thread. That isn't to say one couldn't wind a bobbin with #138, or #207 thread, but there wouldn't be very much of it on that bobbin.

During the Ice Age of sewing machines, when Singer came out with the Universal Feed mechanism (UFA, 29-2, 29-4), meant for shoe cobblers, there was no bonded nylon thread. They used cotton or linen thread. Some of that thread could have been up to 3 or 4 cords. The reason those machines could actually sew with heavy thread back then was because linen thread is soft and very flexible. If wound tightly, you can get a lot more linen thread in a small bobbin than modern bonded nylon. Also, linen thread didn't require as much tension to pull up the knots, thus was not as tough on the take-up mechanism.

I still have a spool of 3 cord thread I occasionally use in my patchers for special jobs.

[MtlBiker]

47 minutes ago, Wizcrafts said:

The Singer (and Adler and Claes) patchers are all lockstitch machines with bobbins. The bottom thread is feeding the bobbin winder, which winds fresh bobbin loads, not the bobbin in use. That bobbin lives in the left end of the cylinder arm, just to the right of the needle and is inside an oscillating shuttle that picks off the top thread loop formed by the needle making a down>up>down jog. The bobbins are extremely tiny and aren't normally threaded with anything larger than #92 bonded thread. That isn't to say one couldn't wind a bobbin with #138, or #207 thread, but there wouldn't be very much of it on that bobbin.

During the Ice Age of sewing machines, when Singer came out with the Universal Feed mechanism (UFA, 29-2, 29-4), meant for shoe cobblers, there was no bonded nylon thread. They used cotton or linen thread. Some of that thread could have been up to 3 or 4 cords. The reason those machines could actually sew with heavy thread back then was because linen thread is soft and very flexible. If wound tightly, you can get a lot more linen thread in a small bobbin than modern bonded nylon. Also, linen thread didn't require as much tension to pull up the knots, thus was not as tough on the take-up mechanism.

I still have a spool of 3 cord thread I occasionally use in my patchers for special jobs.

Geez, is there anything you DON'T know about sewing machines?     Seriously, thanks for the explanation. 

[Wizcrafts]

59 minutes ago, MtlBiker said:

Geez, is there anything you DON'T know about sewing machines?     Seriously, thanks for the explanation. 

My Father owned a tailor shop from the time I was born until long after I left home. I learned to sew and adjust an industrial sewing machine by the age of 12.

[DG1]

On 10/21/2021 at 3:01 PM, kgg said:

 

To accomplish this I used the Darning Tensioner was used to give consistent, adjustable tension as I don't darn and haven't really figured out what the advantage it would provide over the top Thread Tension for darning.

If someone can explain this I would really like to know as I can't seemed to find any information in the 29K manuals.

 

I'm not positive about this but I'm guessing that since there are no bottom feed dogs you could use the patcher for darning similar to one of those singer 47 dedicated darning machines where you manually feed the fabric back and forth similar to free motion quilting. You would of course raise the foot which would release the tension from the top unit, hence making it non operational. The "darning" tensioner will always have tension on it whether the walking foot is up or down.

[Wizcrafts]

On 10/14/2025 at 12:38 AM, DG1 said:

I'm not positive about this but I'm guessing that since there are no bottom feed dogs you could use the patcher for darning similar to one of those singer 47 dedicated darning machines where you manually feed the fabric back and forth similar to free motion quilting. You would of course raise the foot which would release the tension from the top unit, hence making it non operational. The "darning" tensioner will always have tension on it whether the walking foot is up or down.

If your machine still has the bobbin winder tension disks on the front of the revolving head assembly, use them for darning tension instead of the top disks. Just raise the foot and darn it!

[Wildwest2029leathercraft]

Wait can this machine sew thru like 15 oz of leather like 2- 7/8 oz pieces 

[Wizcrafts]

11 hours ago, Wildwest2029leathercraft said:

Wait can this machine sew thru like 15 oz of leather like 2- 7/8 oz pieces 

It can sew 15 ounces of shoe upper leather. These machines were built to fix (patch) shoe and boot uppers, but not the soles. The bobbins are tiny due to the small 1 inch width of the nose on the arm. They are meant to use relatively thin bonded thread, usually #69. There used to be boxes of a gross of prewound bobbins available that eliminated the need to wind metal bobbins. Anybody who does have to wind their own bobbins keeps a magnetic pickup tool handy to fin them after they fall out of your fingers and roll across the floor to places previously unknown. When they roll, they also unwind!

The range of thread and needles limits patchers to #138 bonded thread. There isn't much capacity on the bobbin for this size of thread.

So, while a patcher can sew 1/4 inch maximum thickness, it is normally into soft to medium density shoe or chap leather, not veg-tan. I would limit veg-tan to about 10 ounces.

Note, that the maximum stitch length of a pristine, late model Singer patcher is 5 stitches per inch at 6 ounces. As the thickness increases, the stitch length decreases. One might only get 8 to the inch at 15 ounces thickness, or less if the bottom drags against the throat plate. It helps to keep the throat plate highly polished/buffed and use a foot with aggressive teeth to pull the leather along. These feet leave noticeable tooth marks in the top of the leather.

[Dwight]

On 10/18/2025 at 11:32 AM, Wizcrafts said:

It can sew 15 ounces of shoe upper leather. These machines were built to fix (patch) shoe and boot uppers, but not the soles. The bobbins are tiny due to the small 1 inch width of the nose on the arm. They are meant to use relatively thin bonded thread, usually #69.

My Chinese copy of the Singer came with a bobbin that does not hold much like you said.  It also said I had to use thread that wound a certain way.

I generally use carpet thread for just about anything I sew that is not done on my Cowboy4500 . . . it is strong enough that it can cut your fingers if you try to jerk it and break it.  

Using a mike . . . it is just a couple thousandths bigger than the cotton thread that came in the machine . . . and it works great so far . . . and I've never been able to pull a seam apart that I've sewn with it.

I used to get it at Joann's . . . will have to go to Michaels from now on from what I heard.

May God bless,

Dwight