Sunday, May 1, 2016

Champion 77 Presser foot, Thickness Adjustment

Finding out the hard way why the presser foot height is important; it is important because without compensating for very thick leather (by raising the foot) I get a lot of double stitches.

I love this grahamsshoeservice video on running the machine and of course never under stood the value of the adjuster until I had some time on it.


Leather strip

I never understood why the original machine didn't come with a proper adjuster so after weeks of consideration I fabricated this retro-fit.
Retro-fit design was critical; I did not want an irreversible modification in case I didn't like it or it didn't work.
I realized that I could bolt a 1/4" plate to the underside of the casting if only the 5/16" slider guide had a longer threaded section.

I went with the 5/16 - 18 machine screw so the adjustment is fast; fine adjustment is not necessary.

To adjust you press down on the lift pedal turn the screw up or down and you are on your way.

I like it better than the scrap of leather.

Added a grommet to the cap head screw and a spring for friction:



Wednesday, June 24, 2015

Champion 77 Needle, Cast-Off, and Pressor Foot alignment

Over the past couple of years I have got more practiced with the 77 and am having good success most of the time.
When it starts missing or worst of all not stripping one loop before the next, its time put the work aside, find an uninterrupted hour and dial it back in. I use the dimensions from the instruction book but there are so many interrelated dimensions that you just have to play with it.

These pictures show the arrangement / relationship between the components when it is running SWEET.







Tuesday, October 7, 2014

Champion No. 12 Channeling and Grooving Machine

OK World who else has one of these? This thing is seriously rare; I have reached out to all of the North America shoe machine companies and NOTHING, its like the machine came from outer-space.
I am hoping that my friends from around the world can help, I need any print data on it. 

To get it to Michigan I had to have it shipped from Hawaii, it didn't get to Hawaii by itself now did it?

I am in the middle of a complete restoration, it was completely frozen, none of the rotating parts would move. With great care and patience I freed up and removed everything down to the castings.

It's all there except for the broken knife blade and the grooving cutter. I think I know how it works and what it was intended to do, I am sure I can get it to cut channels.
Well I am nothing but being a tenacious searcher; I started with the names of the Champion Engineer guys that I knew of and added "patent" to the search and came up with THE patent docs on the No. 12!

These and the full patent description are going to make all the difference!!! Now I know what the one missing part is supposed to look like.

So now I have a special update to the patent drawings for you;

Thats much better! A few hours on PS and we have something that really pops.



More to come:::



Sunday, June 1, 2014

Champion 77 Foot Pedal Ergonomics

After just a few runs I recognized that the left foot pedal is very high off the floor.
If you have run the machine you notice that the pedal needs a full push; if you make a slow or partial pedal actuation the machine reacts slowly and without the necessary force or speed to make a firm stitch.


The problem with the amount of pedal travel is how far off the floor your toes are when the pedal is full up. Basic Human Factors dictates that the operators ankle angle should be no less than 85 degrees; or the ball of foot should be no more than 5 degrees off the floor as measured from the heel.

Very simply I attached a 2 x 4 to a 5/8" piece of plywood. I will adjust the shape and size of things if necessary in the future as I gain more time on it but the results so far are much better. You need a hole to allow the foot pedals to pass the plywood.

With your left foot extended as high as it needs to be (without the foot pad) you are almost standing on one foot, which doesn't help you stitch concentration at all! Stitching is such a concentrated effort and so pressing the pedal needs to be as effortless as possible. All of your thoughts should be on the next stitch and not on how cramped your left foot is.





In classic automotive occupant packaging the drivers foot is shown at 85 degrees of flexion. We place the accelerator pedal so that when the car is at idle with no pedal deflection (waiting at a traffic light or stop and go traffic) the ankle angle is no more than 5 degrees from perpendicular to the lower leg.


Also I forgot to add this YouTube that helped more than just about anything: Instructional: McKay Stitcher

Thanks to grahamsshoeservice


Update 11.07.16
Foot pedal foot rest fine tuning; I added a slope to the end of the 2x4 making it easier to tip my toe down while leaving my heel engaged


AND I wanted a dust cover over the thread so I waited for the right plastic container to come along and voila!

Thursday, May 15, 2014

Champion 77 Thread Lube Pot Liner

I am getting much more comfortable and skilled at using the 77, I have two pair of sandals completed so far.
However, I am and most likely will continue to use it about once a month and after cleaning and restoring the thread lube pot I realized that I simply will not leave the lube in the pot for weeks or months at a time. The lube drys slowly, thickens up to a syrup, and leaves a film all over everything.

I have been sucking out the unused lube with an ear syringe then cleaning and drying the pot but I thought that a liner would be the correct answer. It turned out to be an easy one day project that came out the 1st try.

I have a DIY vacuum form set up which is the ideal process to make this part.

1st I needed a pattern and decided to make a cast of the inside of the pot.
Two problems:
  1. Casting directly into the pot would require a release
  2. The pattern needs to be undersized to leave room for the plastic thickness.
I used an old die makers method of lining the mold (pot) with wax sheet which I happened to have from my plastic model making days. Its called Parafilm "M". By its self it is too thin 0.005" but that was OK because I could layer it and using the heat gun was able to get a nice thick lining, I was shooting for 0.030"






Next I mixed up some Bondo poured it in.





It popped out without hardly any effort! (I was shocked and worried)





I had to sand and put a finish coat of Bondo on it and then took it strait to the vacuum table without any finish or release on it.


Used some clear plastic from some packaging I scavenged and it came out perfect the 1st try (when does that ever happen?)





Yes it is fine, and yes I am obsessive compulsive!



Thursday, November 7, 2013

Champion 77 Whirl Replacement

I decided to replace the Whirl and Pinion today. Following the instructions in the manual of course but because the machine was already stitching very well I took careful note of the small hole location before I removed it, and that was a good decision.






The cover piece S-503 has some serious wear on the underside but I am going to keep it as is for a while.

FYI, on the left of the picture below is my standard way of repairing nicked screws; its an extremely fine 1/4" square file. Here is the trick to not nicking the screws on an old machine; you must push harder down onto the screw than you are forcing the turn. Sounds simple but the more stuck the screw is the more down force you must apply, any way you can find to push down on the screw VERY hard while turning is going to improve your chances of not slipping. 



The new Pinion & Whirl, pretty expensive at around $45 each.








The new Pinion was longer than the old one and so the adjustment instructions in the manual worked very well. There is a screw in the middle of the upper gear that moves the pinion up and down; if it is too far up the cover piece will not seat down and forcing it binds up the whole system; you can feel that the horn won't rotate due to the binding or trys to turn around while stitching.







The alignment of the head is easily done by aligning the marks on the main shaft, this is about half way around the cycle.







 It turns out that aligning the whirl to the mark on the horn head S-502 was 180 deg. from where the old one had been. When I tried the machine after assembly it did not stitch at all so I reset the whirl back to where it was originally was and all is fine. More experimentation to come.






Good stitching, I tried a nice groove on the top and it really compresses the two threads together making a very nice looking stitch.



Friday, November 1, 2013

Champion 77: Some Patents

Fascinated by the old machines and while trying to date my 77 I came across these patents.


Although they may never match a production machine exactly patents are good for setting a timeline and more interestingly establishing the intenet of the design.



The needle and shuttle mechanism


After working with the machine for a while it is really just the head that is doing everything, the horn is mostly along for the ride.


This one shows the outline of the shoe insito.