Proper polishing of parts

I've seen WAY too many "experts" (YouTube, and photos on this site) attempt to polish/smooth trigger parts...BADLY !
So here's a little help.

The way that many seem to be doing the work are actually changing the angles of the given sliding parts and doing more harm than good. Using "round" stones to polish "flat" parts (!!!), WHAT THE F... .

Anyway, here's a way to keep the, as designed surface angles CORRECT while completing the polishing process, WITH...minimum material removal.


Works on many different metals, and parts.
Having the ring and pinion gears done on my Hot Rod.

Mike
 
It is my understanding you need to be careful here.

I know someone, spiffing up a Husquarna MP as i recall a old Swedish M37, the fool tested it with a full mag, and that ended up being a full mag dump as there was no stopping it once it got going after his ghetto job.

At my apprenticeship, out first job was to make 2 hacksaws, and they got polished to a level where if one of the other apprentice touched one of your hacksaws a fight would almost erupt.
The regular steel they was made off, well polished to mirror finish over several weeks ( most by hand but in the end we was allowed a polishing brush in a drill press )
The place kept the best one and we was allowed to keep the other one.
 
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Besides possibility ruining the trigger by removing too much metal, there is a hidden hazard to polishing the parts.

The more expensive airguns use precision machined, high carbon steel, tempered parts in their trigger blocks. A bit of polishing can smooth any tooling marks.

To save money, budget airguns are often made with stamped low carbon sheet metal parts that are CASE HARDENED. Stamped parts typically have rounded/angled edges and tooling marks/burrs resulting in rough, poor fitting parts.

The case hardening process impregnates the low grade steel with carbon creating a THIN (a few thousands of an inch), hard, bearing surface. Polishing the surface can remove that hard layer, exposing the soft metal.

The soft metal wears easily and can result in a dangerous trigger. Eventually the sear may release even if the safety is on!

Just a heads-up. Be safe!

Cheers!