Feed dog/inner foot binding up?

[mwpdx86]

I have a Consew P1206RB and it seems to be working for the most part.  Occasionally though (like one out of every 3-5 stitches) when running the machine very slowly or with the hand wheel, it seems like the feed dog and the inner foot (the one with the needle going through it) will sort of jam up.  Like it turns fine, with almost no resistance, and then right when the foot comes down to meet the feed dog, it freezes up and is very hard or impossible to move/advance.  Until recently, I had just been backing it off with the hand wheel a tiny bit, and then stepping on the pedal and that seemed to work usually.  But then yesterday, I noticed that when this happens, if I hit the knee lifter just a little, something (I think the feed dog) makes a pretty noticeable 'sproing' sound and then it's easy to turn again.  My completely inexperienced, in-my-head diagnosis is that the feed dog is sometimes moving backwards too slowly/quickly/not in sync with the foot and causing a weird jamming and then releasing the pressure with the knee lifter lets it slip back to where it should be and then everything works normally again for a few stitches.  No idea if this is possible or whatever, that's just what it seems like feeling/listening to the machine.  As far as I know, the machine has been this way since I got it a few months ago.  I haven't used it a ton and I'm hoping I haven't been messing it up somehow by using it like this.

[CowboyBob]

Have you taken the end cover (over the needlebar) & lubed every pivot point you can see there's at least 14 or more spots that need some lube once a month.Even oil @ the top & bottom of the needlebar & the pressure bar where it runs through the casting & the nut on top.

[mwpdx86]

Not yet but I can try.  I was under the impression that this was mostly a self oiling machine (apart from some of the walking foot mechanisms in back) but I can get in there and see what it looks like at least.  

[brmax]

Here can be some tips on pages 3 with points of lubrication, and sometimes others only people as Bob or Gregg may know about having seen the insides of these beast. 

Anyway good luck

Floyd

http://www.consew.com/Files/112347/InstructionManuals/P1206RB.pdf

Edited November 11, 2017 by brmax

[CowboyBob]

The main bearings & upper feed parts are the only parts that are automatically oiled.

[mwpdx86]

I've lubed all the parts that look lubeable, and it still seems to lock up intermittently.  I've examined it a bit more too and when I release the tension via the knee lift, both the foot and the feed dog snap upwards (not back/forth as I had originally thought).

[mwpdx86]

Also, and this may be completely unrelated, the stitch length knob won't go smaller than three.  The smaller I go, the tighter it feels and can't seem to get it to go past #3.

[brmax]

Its possible the feed dog is loose, if im understanding your description. Its normally a slow continuous movement. May have to remove the motor belt, threads and feed dog cover and carefully get a better view if possible.  

With the stitch knob is there a spec on stitch per inch, or how is it referred in the book. Some machines refer differently, by that 3 per inch is a long stitch. 

Good day

Floyd

[Wizcrafts]

Feed dogs are usually only held onto the fork with two very small machine screws. The pressure exerted by the presser foot/feet on the feed dogs can loosen them over time. The higher the foot pressure, the more likely they are to loosen up and move out of specs.

Tightening feed dog screws can be a challenge. I keep a very long (10"), narrow blade, big handle screwdriver for working on both the throat plate and feeder screws. I find it best to remove the faceplate from the head in order to get the best possible angle on the feeder screws. If the feed dog screws are allowing it to move around, tighten them as much as possible.

[CowboyBob]

8 hours ago, mwpdx86 said:

Also, and this may be completely unrelated, the stitch length knob won't go smaller than three.  The smaller I go, the tighter it feels and can't seem to get it to go past #3.

Do you know if you push on the reverse handle when you make your stitches shorter it relieves the pressure off of the knob .