Singer 7-33

[VanRhodes]

I picked up a singer 7-33 yesterday from a local guy here in Stockholm yesterday, honestly, I never thought I would have that much luck scoring a 7-33. As expected, its a bit of a fix-er-up. I'll need to clean her up good and buy a new thread take up spring and a new thread guide for the thread tensioner and I plan to get those through Gregg. But upon further inspection I noticed something weird and I wanted to check with any of you guys that has experience from the 7-33 if this is the way it should be. Please see linked video. (Sorry about the standing video format) https://www.youtube.com/watch?v=lb2zECk0ESg 

It would seem to me, that the connecting shaft between the end that goes to the eccentric feed and the lifter for the inner foot should be a one piece shaft. e.g if it moves on one end, the other should move as well. But this is clearly not the case at the moment. Is this the way it should be? 

The second issue I'm having is that the outer foot, or the vibrating/walking foot, is dragging behind and really isn't moving as its supposed to do as is evident in the following video.

https://www.youtube.com/watch?v=zBDwkJBpYAs

Being very new to the machine I'm not quite used to the mechanic's involved and I have this far failed to find much in the way of useful information regarding these issues so any help from you guys would be greatly apprechiated. Thanks in advance. 

[Constabulary]

Videos do not play...

[VanRhodes]

Weird. Try now, I changed them from private to unlisted. Dont know why they ended up as private though, must have been some preset that was saved from an earlier upload,. 

[VanRhodes]

Gregg got back to me, saying it looked like a broken tapered pin in the rocking shaft and upon closer examination it turned out he was right. I broke out the dremel and some hardened steel bits and drilled the tapered pins to relieve them, and could then continue to hammer them out of the sockets. I temporarily affixed the rocking shaft by inserting temporary pin in to the socket to test the function and it appears to be working rather smoothly now. Next stop is the Keystone Sewing webshop to order some parts, might as well order a couple of tapered pins while I'm at it

 

 

[Yetibelle]

That machine looks like it is in great shape.  Really nice find.  Do you have a picture of the pin you replaced?

 

[VanRhodes]

I havent received the pins yet(they're in the mail), but I included a picture clearly showing the broken pin, still attached to one part of the rocking shaft. These are the pins I ordered. The ones for the 7-33 are apparantly the same as those used for the Seiko SLH 2-B http://store.keysew.com/catalog/product/906c427e93724c929ff31a838537115f

 

 

[Yetibelle]

Now I'm going to have to look at mine to see if that is loose.  I would have never noticed that.

 

[VanRhodes]

According to Gregg, those pins often break due to the pressure of the spring on top so go ahead and check yours. It should be clearly noticeable if something is broken. 

[trash treasure]

I'm restoring an Adler 20, and encountered the same issue, on the OTHER end of that rocker shaft.

In my case the pin wasn't broken, but very worn, and the hole in the shaft was wallowed out - You can see the end of the old pin in the photo

The result was a lot of lost motion -There was a set screw (on the towel) through the arm, but that didn't help, as it just slipped on the shaft.

Anyway, the pin was just a standard #2 taper pin - I bought the next size (#3), and used a taper pin reamer to size both the arm and the shaft in one go - It only needed a few thou. taken out , and just the narrow end of the #3 pin tightened everything up nicely.

I also machined a little dimple in the shaft for the set screw - It's all good now.

Just make sure the shaft hole is OK before you put it back together - Try the new pin in the hole - It should be a PERFECT fit.

If the hole shows any "ovaling", or shows some space around the pin anywhere, you probably need to ream the whole shebang.

 

[Gregg From Keystone Sewing]

2 hours ago, trash treasure said:

1)Anyway, the pin was just a standard #2 taper pin - I bought the next size (#3), and used a taper pin reamer to size both the arm and the shaft in one go - It only needed a few thou. taken out , and just the narrow end of the #3 pin tightened everything up nicely.

2)I also machined a little dimple in the shaft for the set screw - It's all good now.

3)Just make sure the shaft hole is OK before you put it back together - Try the new pin in the hole - It should be a PERFECT fit.

4)If the hole shows any "ovaling", or shows some space around the pin anywhere, you probably need to ream the whole shebang.

1)That's the way, no other way to do it.  Usually we can repair by going one size bigger on the taper pin, or go one size taper pin bigger.  At some point, though, the taper pin's thickness becomes equal to or greater than the shaft on either size of the pin, then it's time to replace the arms and shaft and start over again.  Not cheap, and not easy to realign, but it's not often that we need to repair like this.

2) The small set screw on bottom and or dimple is only really good for installing the pin; the amount of pressure going through this is such that a set screw is going to do very little here; the taper pin is doing almost if not 100 percent of the work.

3)Absolutely correct.  Pin hole should like clean as a shotgun barrel, especially where the arm and shaft meet inside the shaft.  Otherwise the pin will not be in the hole for long.

4)Again, absolutely correct.  BUT, that's if the hole is ovaled out, exactly as stated.  Then, we need to go in, with the correct reamer, again, making a large size pin, and fixing that way.
The important thing to understand is that when parts are properly fitted and the pins break, that does not at all indicate that the parts are worn; it may just only mean that the pin is broken, in three places, and needs to be replaced.