Walking foot - feed dogs marking leather

[RockyAussie]

Just found a pic that shows the 331 and it's adjuster.

[RockyAussie]

Here's the pics of the 335 with the sleeve pulled up about 3/8". This still allows the screw when wound down to come into play and have some meaning I guess. Note the sleeve is no longer visible from inside against the outer spring. Sorry the pics are not the best, it is quite dark down the back in that container.

[dikman]

Poor little machine, all neglected and lonely in the dim dark recesses of that storage container.

[RockyAussie]

It deserves it. It's got one foot tooo many for my liking..

[dikman]

. Well, I'm prepared to give it a good home where it will be appreciated and let it see the light of day!

Anyhow, I got curious and just had a closer look at mine. The outer spring is fixed and is non-adjustable, the inner spring provides the adjustment (not that it seems to make much difference in the normal setup). The mod you did, however, can allow the inner spring to have more effect. By raising that "sleeve" it reduces the tension applied by the inner spring when the adjusting screw is all the way out so when you adjust the top screw it should have more effect. Of course, to get the best out of it an awfully long screw will be needed . Seeing that I haven't really been able to find a screw with the right thread size I might run a tap through to use a more standard size and then make a decent adjuster, now that I know how it works.

[RockyAussie]

I think by raising it as I have done the outer spring has less tension on it and the inner spring then allows more of an adjustment. As I did this for wallet type work I would say if you wanted it to do heavier type work you would only take the sleeve up 1/4"(6mm).In the location I have this one the adjustment bolt does not feel to touch the inner spring until about 3/4 way down. As for my 335.... its staying in the sin bin.The Adler 69 as Uwe pointed out has a more logical adjustment system and I only every use that when I want to do thick bag handles and such. The 331 does most things just right, It's just a shame they stopped making them.

[Gregg From Keystone Sewing]

I think Pfaff may sell various springs for this?  I'm not sure at all, just speculating.  I was looking in the books for 1245 and 335s with this type of two spring pressure foot setup, with nothing for sure.  I've seen different subclasses with different spring part numbers, maybe that's it?  

[dikman]

Rocky, on my 335 raising the doo-hickey (technical term) on top doesn't have any effect on the outer spring, as the spring pushes against the top of the housing regardless of the doo-hickey's position. All it does is change how much additional tension can be applied via the inner spring.

Gregg, what you say makes sense, although I don't know if that's what they do.

[RockyAussie]

OK. I did it quite a few years ago and the pics above of Uwe's 145 may have made me think that the spring rested on the doo hicky. As long as it works,as it did for me that's the main thing.

[dikman]

That's ok, the memory starts to go as you get older .