The Offcial Machinist Thread: Revised 01/04/2014

[wyz2285]

Gippeto by sea salt, is simple kitchen salt ok?
Also white household vinegar is vinegar right? I mean the same as the white vinegar I can find in my kitchen?
Sorry about this, I just want to make sure everything it's right.

[turkeypig666]

I just started college for machining 1 month ago and doing cnc next year. I could machine myself a piston for sure now, but they want us to wait at least 1 month before doing a personal projects. Might try to get myself a little lathe for stuff just like that.

[Labtecpower]

Nice job on the knurling. 8)

Ditto! Hmmm, time to get me that knurling attachment methinks...

Thanks guys

Go get it

IMO it's a great method for finishing stuff, gives a nice grip and makes it scratch less.

Takes some practice to get right tough..

Also make sure you secure your tool clamp very well, otherwise it'll rotate because of the forces involved.

Unless you get a "clamp" type knurling attachment I doubt if the sherline is sturdy enough to take it..

[turkeypig666]

I'm actually hoping to get a small lathe soon, but have no clue of what they are worth or wich size to get. I know I probably don't want more than 24"

[Gippeto]

Wyz...try the salt you have. Not sure if iodized salt will work the same, but can't see why it would not. I used sea salt, so that's what I wrote down.

The vinegar from your kitchen is the right stuff. Looks kinda like water...tastes kinda bad...says vinegar on the front of the jug...yup, that's the stuff.

Try steel scraps for the first couple attempts...play around with the final sanding grit to see how it affects the final finish.

[jackssmirkingrevenge]

Technically "ácido acético" Vinegar is typically a 10% or so dilution of acetic acid.

[wyz2285]

Thanks guys.
I went to gather the stuffs. The hydrogen peroxide I got from pharmacy is only 3%, will it work?
About the salt, as I leave near the beach I can make true sea salt myself
Oh and about the vinegar, mine is white, taste bad and smells but it's says apple vinegar... Will follow JSR's tip.

[jackssmirkingrevenge]

High concentrations of peroxide are difficult to obtain, it's dangerous stuff with dangerous applications. I've seen up to 6% in hair bleaching products. Back when I had access to a laboratory, I had 30%... easy access to chemicals is one of the few things I miss here.

[wyz2285]

I'm in college study material engineering, I've access to 2 big laboratories

[jackssmirkingrevenge]

... so if you have access to higher purity compounds, get your hands on those instead of the poorer domestic equivalents

[inonickname]

I'm in college study material engineering, I've access to 2 big laboratories

Which you can't readily take anything from (especially anything interesting) without a very good reason?

Edit: Incase it doesn't go without saying, don't steal explosive precursors people

[wyz2285]

I actually asked my teacher about bluing and he allowed me to freely work in the lab when it's not been used.
About explosives, I can get large amount of potassium nitrate from a friend and for this semester's chemistry project I'm thinking about making a candy rocket.

[inonickname]

I actually asked my teacher about bluing and he allowed me to freely work in the lab when it's not been used.
About explosives, I can get large amount of potassium nitrate from a friend and for this semester's chemistry project I'm thinking about making a candy rocket.

In that case, cool- that's the right way to go about it. And here I was thinking someone was thinking of nicking some TATP precursors (PETN is better, shame on you ).

Candy rockets are pretty cool, though be warned that dabbling with energetics is addictive

[wyz2285]

Candy rockets are pretty cool, though be warned that dabbling with energetics is addictive

First candy rocket, then with a nuke warhead ?I just want to watch the world "BANG"
BTW did I tell you that I share the same labs as the mine/resource department? They have A LOT types of "magic" stuff

[turkeypig666]

How much would someone here charge to make me a small 3/4 piston from plastic or aluminium? I could do it myself, but have no lathe at the moment. Thanks.