Polishing Machine Parts

[Darren Brosowski]

I am working on a 1910 Singer 45k25 for a customer and it is not a bad machine - a new feed dog and shuttle backing ring fixed up the bottom end issues - but both tensions had the wrong springs.

Changed out the springs and top tension plates and noticed that someone had done some polishing on the bottom tension post. Set the tensions to what felt about right and off we went - first few stitches were ok then we started looping on the bottom. I noticed that the second tension was loose so did it up and had the same thing happen. The post had been polished so much that the nut would not bind to the thread properly so I fixed it by using a second thumb nut as a lock nut.

I see this sort of thing a lot on machines and the moral of the story is that cleaning is great and polishing is ok but when there are fine tolerances involved be gentle. At most I use fine steel wool to polish any contact parts.

Many a good 29k has bee destroyed by the over enthusiastic collector

[Rockoboy]

14 hours ago, Darren Brosowski said:

when there are fine tolerances involved be gentle

Very good advice, thank you Darren.

[CowboyBob]

You would think they would know better than to polish the threads !! That's as bad as people that get an old machine & want to       (re-store) it so they strip all apart,break & or lose a few things & then call us to help bail them out,I sure wished these parts were available but most have been dis-continued yrs ago.When it would of been better just to clean it up the best you can & use it with the dirt inside it.

"If it ain't broke don't fix it!"

[plinkercases]

2 hours ago, CowboyBob said:

You would think they would know better than to polish the threads !! That's as bad as people that get an old machine & want to       (re-store) it so they strip all apart,break & or lose a few things & then call us to help bail them out,I sure wished these parts were available but most have been dis-continued yrs ago.When it would of been better just to clean it up the best you can & use it with the dirt inside it.

"If it ain't broke don't fix it!"

Reminds me of what one of my mentors in business told me..."Just because you can do something doesn't mean you should."... handy even outside work!

[DonInReno]

I really like scotch brite pads, as do most of us (especially the super fine ones designed for Dremel tools), but wow do they round over, ripple the surface and just generally ruin a lot of parts if not used sparingly and in the right situation.

A local machine shop has a display of parts ruined by careless scotch brite disk use... Lol

Edited July 1, 2018 by DonInReno