Singer 7-33 Stitching problem & parts

[TinkerTailor]

[Gregg From Keystone Sewing]

22 hours ago, hackish said:

Wanted to share some success...

So... what was the problem? I can't say for certain but I can rule a few things out. I feel like the issue was probably the lower tension spring. The one Gregg supplied was a slightly different shape than the ones I had here. I think it will require just a little fine-tuning of the tension to make the stitches as perfect as I can get them.

 

Sweet, it takes effort on both sides, and you were able to understand and articulate what parts you were after to make this machine work.  You never know how these things are going to go when I send out parts and someone else does the work, glad I was able to be a part of getting your machine back up and running.

Edited October 12, 2016 by Gregg From Keystone Sewing

[hackish]

Next question I have... does anyone have a Singer class 7 that has been modified for higher lift? This machine was supposed to have 1 1/4" lift but I never thought to measure it when it arrived since my bigger priority was getting it to sew. I measured it yesterday and it has 0.750" excluding the height of the feed dogs. I would like to see any photos of how the mod is done so I can send them to the original seller and explain that it definitively does not have the modification done.

 

[CowboyBob]

Lift the foot up all the way & you'll see where it hits the casting,you take all the parts off & put it in a bandsaw & cut the underneath side of the casting(where the needlebar comes out) & fill in the slot on the lifter handle backet (flat piece in the side) w/braze so the slot is shorter.

[mikesc]

27 minutes ago, CowboyBob said:

put it in a bandsaw & cut the underneath side of the casting(where the needlebar comes out)

You've just got to love the nonchalance in that phrase.

[hackish]

The seller claims it has been modified. He's sending instructions so I'll run through and verify them. I don't have a "stock" 7-33 to compare it with. I'm particular enough that I'd put something like this on a mill and cut it so you couldn't tell but there aren't many people who are this anal. Can anyone snap a photo of a modified or unmodified specimen?

[Gregg From Keystone Sewing]

We normally put these into our 1960s Bridgeport to cut the frame away, but hacksaw has and may be done in the future as well!  I've seen my dad cut the frame away on these with a hacksaw more than once, and is perfectly acceptable.  Looks like someone did this highlift with a hacksaw as well, and machine may have shown up to us in that condition.

Kindly note this is not the only thing we do to get this machine to one inch of presser foot clearance from Singer factory standard 9/16"  

[hackish]

Sure took some looking to see which part was cut. I'm pretty confident that this thing was never modified to 1 1/4" lift. 3/4" difference is a _LOT_. I can see there was some hackery done to the lifter link. Maybe I can bling the machine up and cut a piece of 1/8 SS with a relocated slot. Looking at how the mechanism lifts, I suspect I could take some material off the machine frame and some off the lifter assembly. I pulled the link off and the piece is cracked anyway.

[Singermania]

Yeah that's a pretty ordinary modification.   Singer in their wisdom work out what they think the max for these machines might be, you can go greater but expect to put the machine under extra stress.    There are new machines on the market with the kind of lift you are talking about.

[1985]

On 10/6/2016 at 2:04 PM, Constabulary said:

I don´t know the Class 7 machines but can you try to adjust the needle bar hight or is the needle bar pinned? I would guess you have to lover the needle bar a little bit.

As I am no means an expert on the industrial machines but I do own a 7-33 , not actually used it yet, until I check and clean a few things first, As it was stated you did fix the issue changing a couple of things , so I thought ill still suggest what I check ,

But its usually obvious to blame the tension but as it stitches then at some point the thread gathers or misses a stitch surely there has to be other factors that all may contribute to 1 issue, as I say I am no expert but some times its not the obvious that is the usual culprit for the issue,I my self run through a list , not all but it helps to check not the obvious. 

Left or right twist thread top side- needle thread to thick or thin for the groove in the needle - pushing the work through when should only guide- needle plate hole become to big allowing the surrounding material to raise down and up around the needle snatching the thread- check to see if bonded nylon does not untwist in fingers and thumbs when testing, Thread on the spool,make sure its not sticking together as it comes of the spool and needs to come off smooth ,but not to loose` neither to tight -If using thread that needs wax make sure the thread is getting its lube- check thread is not fraying ie rubbing on all passage ways it runs, check correct needle for material and thread- needle not bending as it pushes through material- check for wear grooves in inside and out where thread passes, 

I suspect different softer materials it may not happen but hits a problem with certain tighter material or thickness , this it where the needle thickness and point is very important,and so thread, if theses were all checked correctly and tension correct then I suspect it was a number of things contributing to the issue. not just one,