29k15 shuttle gear remanufacturing

[29k15engine]

Hello all,

I have bought and fully restored a 29k15, the fact is there are alot of these marques out there so it seems a shame that they can turn into large paperweights due to the fact that the shuttle gears and rack are unavailable. Im looking into what would be required to make all three gears and rack.

If i could get the original gear and rack engineering drawings it would be hugely beneficial however i think these are no longer in existence.

The good thing is that mine has light wear plus the end of the rack gear is virtually profle untouched and a good candidate for profilling the shape to make a hob for gear cutting.

 

Here is my 29m after i restored it ,paint ,decals ,new pulley ,follower and a lever spring made by myself from 01 grade steel and then heat treated to make a spring, i also made the foot height adjuster.

 

Any help on info would be appreciated

[jimi]

Hi There, Well done on your restoration job, It looks really good and the decals also look nice. I do not think you will find any drawings of the pinions from Singer but maybe someone has made a drawing up at some time because this is the eternal problem with the old 29k machines, the gears and rack wear down and people by new parts from the internet advertised for these machines but they are really only for the newer models 29k71,171 etc. There is someone on Ebay selling the leading pinion for these older models but you never see the long racks new for sale, only for the newer 29k71 types.  

[CowboyBob]

Nice looking machine you have there.

The problem with these older models w/o the steel ends is the casting where the rack slides against can get a groove worn in it that requires brass to be welded to the backside of it as a shim to get the gear closer to the pinions.I'm certain this is why they re-engineered & adapted the replaceable ends on all of the newer models.We have also seen where the hole where the shuttle rides in enlarges to a point it is so loose that it won't sew correctly either.We use .950 as the limit & anything beyond that we strip them for parts.

[29k15engine]

Many thanks Cowboybob and Jimi. Its my first machine, before this I made a leather jacket from scratch with a handheld speedy stitcher so its luxury having stitches mechanised.

I can see that the rack can wear the back of the cast casing, wonder if a new slightly thicker rack would be an option here, then it could be honed to fit (Most new parts now need honeing, e.g the new pulley cam I bought took a whole evening to fit, at first the follower would not even go into the cam groove)

As my 29k had been painted when I bought it a horrible blue I carefully sanded it with a motorised finger file right back to the casting, then used some black etch primer, 2k auto paint brushed on and hand sanded, then sprayed 2k laquer followed by decals and then the same ammount of laquer.

The machine came with the correct treadle table which I am now restoring. It stitches 6 to an inch.

As a side not I have found a "possible" stock of shuttle gears 8608, i have ordered 2, Im not sure if they are new old stock or just good old ones but took a punt at 10 euros each.

As 2 is all I need here is the supplier.

http://sitomaco.es/product_info.php/products_id/4445

 

below is my first leather jacket, as said made by hand with a speedy stitcher.

 

Just to say Cowboybob your machines are impressive.

 

Mat

 

 

[29k15engine]

The 29k15 was £40 in a junk shop so im pretty happy, the jacket however is too heavy for everyday used so Im on the lookout for some nice leather under .9mm maybe nubuck or nappa, I enjoy the challenge.

I have had a play with the 29k and made my wife a leather bucket bag (she wanted brown leather so an early present for my mum) it didnt miss a stitch so im happy.

The copper rings are made from copper brake pipe wrapped round a pipe, then cut and formed into a ring.

 

Hope you like, now back to gears and racks..:)

[29k15engine]

Im now thinking maybe I have fallen into the trap of ordering the wrong shuttle gears....

I have always gone on the part numbers in the singer29k2.pdg here

https://www.college-sewing.co.uk/wp/wp-content/partsbooks/Singer/Singer 29K2.pdf

which shows the 29k15 as using 8608 following pinions

this topic

https://leatherworker.net/forum/topic/88993-singer-29k70-gearbox-inspectionShows 3 gears which do not look like mine, the 4th picture shows what my gears look like.

 

So the question, what is the part number for my gears? is it 8608 if that is correct has my supplier put the wrong picture up here.

 

http://sitomaco.es/product_info.php/products_id/4445

 

any help would be appreciated, especially if you speak spanish as i do not.

 

Mat

 

Edited June 25, 2021 by 29k15engine

[dikman]

You made that jacket with a Speedy Stitcher???? To say I'm impressed is an understatement!

[Constabulary]

5 hours ago, dikman said:

You made that jacket with a Speedy Stitcher???? To say I'm impressed is an understatement!

agree!

Really Impressive and it really looks cool. Any chance that you have a pattern for this jacket?

[29k15engine]

Thanks for the kind words on the jacket.

I do have the pattern for the jacket somewhere.

The way i did the pattern was to pattern another jacket i had, panel edge to panel edge then add the seam needed depending on what the seam was e.g full felled seam.

I made a mock up of the jacket in automotive fabric i had around as it had a scrim back which had depth to it to try out the seams.

As said the leather is heavy making the jacket too heavy for day to day use, the way i look at it is if you can make a heavy jacket and work out all the folded seams, then a thinner one will be alot easier.

The thicker the jacket the more the fit plays its role, i know very little about tailoring but would say the most important area to get right is how it sits on the top of the shoulder and around the neck, the thicker the leather the more this area matters.

Also with the seams skiving and hammering the leather is needed to get up to 5 thicknesses to lay right.

Lessons i would pass on to my next jacket.

1. Choose the leather carefully, go thinner rather than thick 0.8mm initially ( look at how the leather reacts when its folded and doubled up as some seams may require this)

2. Make a full mock up of the jacket in a cheap appropriatley thick fabric with ample seams to get the fit right around the neck, shoulders and arms

3. Under the arms should go up to the armpit, the higher this area is tailored the better the jacket will move and thus not lift the jacket when you put your arms in the air. However give the whole area more than ample space to move in inside the sleeve plus lining.

4. Wear the mock up and move around, move your arms to get an idea of where the arm needs more space when articulated.

5. Learn and practice full felled and half felled seams until you are happy with the results

6.use basting double sided tape 6mm to join the seams ready for sewing, the sewing should be the last finishing process to lock all your work up to that point. Most basting tape can be removed after sewing, try to attach the basting tape to hold the seam but not under where the stitch is if at all possible( gums up the needle)

7. Practice where the arm joins the body of the jacket, the arm hole needs to match the jacket arm circumference perfectly, enough seams on both body and sleeve which must match as this is sewn inside out.

8 where the end of the shoulder joins the jacket is a critical area which sets up how the jacket arm will hang, its also an area which needs some strengthening on the inside as the arms will try to pull from here when they hang.

Hope this helps someone.

 

Remember your first jacket may not be perfect, but what you will learn is priceless

 

Edited June 26, 2021 by 29k15engine
Spe

[29k15engine]

Note the lining is hard to learn until you realise you are duplicating the jacket just in material, then with a few tweaks you can get it to sit flat inside, note sleeve lining benefits from more rather than less space to move your arm

[jimi]

Agree, that looks great that jacket, and with a speedy stitcher!!! Well done!

16 hours ago, 29k15engine said:

any help would be appreciated, especially if you speak spanish as i do not.

well i would normally help you in this case my friend but i have had a rifirrafi with this guy from Sitomaco and FINALLY after a year of phone calls and emails (most of which he did not answer) he refunded the parts i sent back to him. Some parts fitted and others did not? so you might have better luck.  

[29k15engine]

Thanks jimi,

I used google translate, then took a chance and ordered the parts. Hopefully these parts are what i need. I think the k1 machines used the same follower gears as the k15 just in a configuaration of 3 gears not 2 and a short rack, time will tell.

Im quite interested in making gears for these, i really need a hobby lathe or mill, or make a small dedicated machine to cut these. The more i learn about gear cutting and " hobbing" the more doable it looks.

The rack would also need to be made which could if i was to make it have a length adjustment built in to fine tune shuttle timing.

 

[jimi]

21 hours ago, 29k15engine said:

the 4th picture shows what my gears look like.

Mmm... the 4th picture is of the 29ks that had the detachable gearbox?? If you have a K15 you will have 3 pinions??

[29k15engine]

Sorry jimi mine is like the one on this thread above. This one

 

 

[DonInReno]

For a number of years I've been surprised that someone in a home shop hasn't started producing replacement gears - my guess is the labor costs are just too much to have a reasonably priced part, not to mention there is more to getting a worn out machine to work than just changing gears.

There are a number of good introduction videos for cutting gears and racks.   However, as Mr. Pete says in one of his videos, all it takes to machine a $10 replacement gear is a $5000 milling machine, $2000 in tooling and an entire weekend of messing around with setup.

Gears can be made in many different configurations and sizes - as with Singer's tendency to build machines with oddball screw sizes, my guess is their gear patterns are slightly off from any standard size.   It can be confusing at first sorting out all the information, but just keep in mind metric gears use a different system of measurement and cutter geometry, so ignore that and just look to old school American standard gear information.  All Machinist Handbooks have sections on cutting and measuring gears that would be helpful for anyone serious about getting set up to make gears.  Still, a machinist could come close to oddball gears with readily available tooling and fudging the dimensions for a one-off set of gears if the machine was in front of him.   That's the most expensive route.

Fully machined gear racks and rough length pinion material is readily available.  Using these a machinist would not have to cut the actual gears, but would still have to machine the dimensions to retrofit them to the machine - not a trivial task.

I know of at least one person who has replaced the entire lower arm with one machined from from a solid bar of steel along with new gears and rack as described above.   This was definitely more a matter of bragging rights and the enjoyment of machining, rather than something for profit since the time involved must have been significant.

The high strength epoxies are often used to attach wear strips to worn out parts in industry as an alternative to more invasive repairs.   As CowboyBob mentioned, brass strips are often used on a worn rack to reduce clearance between gears.   Likewise, it wouldn't be impossible to epoxy a partial cylindrical metal band to reduce clearance in the hook area, but the time involved would be prohibitive and the wear is not in an even circle so it would have to be machined round for the shim to have any chance of working correctly.

Having said all that, I'm humbled by clock makers that would simply cut, file and fit all the gears by hand - the skill set and time requirements are quite impressive.

My prediction is that the proliferation of higher and higher precision CNC machines for the home shop will produce a regular Ebay or Etsy supply of gears for these old machines in the near future.

[29k15engine]

Just done a render of the rack on a 29k15 which would be a soldered on item that would replace the end of a worn out rack.

This is acurately measured and constructed therefore I need to make one to see if it works, I have a friend with a 3d printer who can also make one out of steel at work from a 3d file.

 

 

Edited June 28, 2021 by 29k15engine

[29k15engine]

the cog as well, though this may need work. you get the idea though.

 

 

[jimi]

Looking good! 

I would think welding a new on on could be tricky?? the newer types have a eccentric screw to adjust them, just a idea... if it could be fixed with a screw after cutting off the old worn one then drilled and pinned after adjusted?? 

Edited June 28, 2021 by jimi

[29k15engine]

Thanks jimi, I put soldering/welded as I found this intriguing parts listing.

 

[29k15engine]

[Constabulary]

The World was waiting for someone like you    

[29k15engine]

Thanks for that, i have a book on gears and gear construction, i believe the gears these days are not constructed like this anymore, indeed in the gearbox of the 29k the gear profile evolved with different tooth profiles for the 3 gear used in production.

For this reason, i decided to start modelling the gears from actual measurements of a good rack and pinion gear. This way it won't get bogged down by calculation that if slightly wrong will not product the right profile.

I can get these 3d printed in plastic and then cut in steel by a friend. But only when they fit and work.

[Wizcrafts]

2 hours ago, 29k15engine said:

Thanks for that, i have a book on gears and gear construction, i believe the gears these days are not constructed like this anymore, indeed in the gearbox of the 29k the gear profile evolved with different tooth profiles for the 3 gear used in production.

For this reason, i decided to start modelling the gears from actual measurements of a good rack and pinion gear. This way it won't get bogged down by calculation that if slightly wrong will not product the right profile.

I can get these 3d printed in plastic and then cut in steel by a friend. But only when they fit and work.

Once you finalize the 3D coordinates and create a functional part, please start a topic about it in our 3d printers and lasers sub-forum. You can even upload a file for others to use.

[29k15engine]

Going to get the fit right with lots of testing, then hopefully will have an STL file for people to try.

 

The straight forward job would be to provide matching gears and racks.

However the harder but more rewarding job will be to provide parts that can be used with genuine singer rack or singer gears therefore being equal in fit to OEM, thats the bit that will take a little time.

 

[29k15engine]

These prototypes will be the first time i can look how the parts work in reality