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CarForumPoster
Jun 26, 2013


Martytoof posted:

Sounds like some weird resonance in one of the axes but nothing terrible. The vacuum pump is much more annoying

Neat idea in theory, but too slow to be really useful IMHO. I can place parts by hand a little* faster than that.



* a lot

Yea but that thing costs $1000 and you cost way more than that. One could buy several of them for the cost of a year of you.

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Sagebrush
Feb 26, 2012





Gravy Boat 2k

I feel like if you wanted to have an inexpensive pick-and-place machine, you'd do way better building yourself a delta frame. The entire frame, electronics and control system can be had for like $500, and then all you need for the gripper is a vacuum pump, a needle, and a little tiny stepper.

https://www.youtube.com/watch?v=AYs6jASd_Ww

And here's an industrial one

https://www.youtube.com/watch?v=MKW7LTKOhW8

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


Martytoof posted:

Sounds like some weird resonance in one of the axes but nothing terrible. The vacuum pump is much more annoying

Neat idea in theory, but too slow to be really useful IMHO. I can place parts by hand a little* faster than that.



* a lot

yeah im not sure why its running so slow, my taig'll go way faster on rapids

Martytoof
Feb 25, 2003

It's called a hassle, sweetheart..



Is there a decent, cheap CNC stepper driver board that will work with Mach3 or LinuxCNC? I'm kind of working on making one myself and I realized I just don't have the time to layout and design a driver board. I'd rather pay someone $50 or $75 or something and just get a 3 axis controller. The cheaper the better, but whatever.

oxbrain
Aug 18, 2005

Put a glide in your stride and a dip in your hip and come on up to the mothership.


You want a TB6560. Super cheap, 1-4 axes, controlled through parallel port. There are issues with build quality, signal noise, etc. You won't get blazing fast speeds or maximum power out of it, but you can't beat the price.

You can get the basic controller for around $30,
http://www.ebay.com/itm/CNC-Router-...=item4613b55d0d

Or a bundle with some small motors and a power supply for around $100,
http://www.ebay.com/itm/Free-Shippi...=item2ecaa8dff2

Sagebrush
Feb 26, 2012





Gravy Boat 2k

Debated whether to put this here or in the 3D printer thread but it's really more of a hobby CNC thing. Desktop carbon-fiber filament winder:

http://www.kickstarter.com/projects...filament-winder

Not sure that it's worth $1300 when it looks to be more like $250 of parts, but still pretty cool. Now someone needs to build one of these

https://www.youtube.com/watch?v=l4DLr8qHliI

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


got some time on the mill for the first time in months, tried the svg v-carve thing i posted about earlier. came out pretty well in aluminum, just used a regular 1/4" router bit

echinopsis
Apr 13, 2004



College Slice

nice! what kind of alu is it and are you using a lube?

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


echinopsis posted:

nice! what kind of alu is it and are you using a lube?

whatever home depot had in the big rack of sheet aluminum. i used aluminum tap magic and i hate it because it stinks of cinnamon.

echinopsis
Apr 13, 2004



College Slice

we used to find that there was a world of difference between like 8001 and 8005 Ali [or whatever it was], the cheaper stuff that was great for folding bending etc was substantially worse for machining.. maybe it doesn't matter but I guess it's worth knowing that the marine grade was so much easier to cut so if you are having trouble with it cutting clean just something to be aware of. maybe preaching to the choir but I'm risking it

Sagebrush
Feb 26, 2012





Gravy Boat 2k

i think it's funny how rotors thread allows easy identification of those who post in the f.y.a.d. or y.o.s.p.o.s. forums as they begin to adopt the characteristic style even out of the proper context.

echinopsis
Apr 13, 2004



College Slice

this isn't even my final form

CarForumPoster
Jun 26, 2013


echinopsis posted:

we used to find that there was a world of difference between like 8001 and 8005 Ali [or whatever it was], the cheaper stuff that was great for folding bending etc was substantially worse for machining.. maybe it doesn't matter but I guess it's worth knowing that the marine grade was so much easier to cut so if you are having trouble with it cutting clean just something to be aware of. maybe preaching to the choir but I'm risking it

As a person who's job it is to understand aluminum machining chat and metallurgy chat this makes no sense.

echinopsis
Apr 13, 2004



College Slice

it's cool dude I mean I worked 6.5 years machining alu but to be fair neither I not anyone I worked with had any real engineering or manufacturing experience. we found the softer grades of alu chewed up and harder ones machined nicely. idk if I was really trying to say anything but get an avatar or something jesus

Sneaking Mission
Nov 11, 2008



CarForumPoster posted:

As a person who's job it is to understand aluminum machining chat and metallurgy chat this makes no sense.

What Is The Best Metal?

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


echinopsis posted:

we used to find that there was a world of difference between like 8001 and 8005 Ali [or whatever it was], the cheaper stuff that was great for folding bending etc was substantially worse for machining.. maybe it doesn't matter but I guess it's worth knowing that the marine grade was so much easier to cut so if you are having trouble with it cutting clean just something to be aware of. maybe preaching to the choir but I'm risking it

i didnt know

i mean, i knew some aluminums are better than others but given the source material i have (whatever crap I can scavenge from whereever) i just live with it.

I keep trying to find a machine shop that will let me dig through their scraps but this is SF and apparently there are no machine shops?!?

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


Sneaking Mission posted:

What Is The Best Metal?

steel because of that thing in conan

Sagebrush
Feb 26, 2012





Gravy Boat 2k

Sneaking Mission posted:

What Is The Best Metal?

helium. it's what the sun is made of

rotor posted:

I keep trying to find a machine shop that will let me dig through their scraps but this is SF and apparently there are no machine shops?!?

there are a few I know of but none that work with aluminum in such quantities that they would have useful sized offcuts to give away. besides, if there were, you can reliably assume that it would already have been raided by burning men or w/e you call them

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


i think you underestimate the sizes that would be useful to me, but yeah you're probably right about the last part.

metal is so expensive gosh

hayden.
Sep 11, 2007

here's a goat on a pig or something


You should look into smelting (I think that's the right word) your own aluminum. It's super easy and you just throw in whatever crap you have and it pours into neat little bars in the same shape you see gold bars (or whatever shape you want). All you need is a hot plate or some charcoal, a hair dryer, and a crucible. A single trip to a junk heap will get you all the aluminum you need. Or just find people on craigslist throwing stuff out for free, like old exercise equipment.

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


i live in sf and have a tiny postage stamp sized back yard and some kind, long-suffering neighbors. I am not about to start a backyard smelter.

CarForumPoster
Jun 26, 2013


Sneaking Mission posted:

What Is The Best Metal?

It is steel. Alloys of steel can basically do everything they just do it heavier but from super alloys to corrosion resistance to very high strength to great machinability steel pretty much owns.

echinopsis posted:

it's cool dude I mean I worked 6.5 years machining alu but to be fair neither I not anyone I worked with had any real engineering or manufacturing experience. we found the softer grades of alu chewed up and harder ones machined nicely. idk if I was really trying to say anything but get an avatar or something jesus

Oh then yea that is true in precip hardenable aluminum alloys, when the matrix itself is harder it is generally more machinable. Hence why machining stuff as cast suck rear end.

echinopsis
Apr 13, 2004



College Slice

rotor posted:

i think you underestimate the sizes that would be useful to me, but yeah you're probably right about the last part.

metal is so expensive gosh

It's all retrievable by scrap dudes so they usually sell it before you can get it.
have you looked up "profile cutting" instead of machining or whatever it's just perhaps another group of dudes who might have scrap

hayden. posted:

You should look into smelting (I think that's the right word) your own aluminum. It's super easy and you just throw in whatever crap you have and it pours into neat little bars in the same shape you see gold bars (or whatever shape you want). All you need is a hot plate or some charcoal, a hair dryer, and a crucible. A single trip to a junk heap will get you all the aluminum you need. Or just find people on craigslist throwing stuff out for free, like old exercise equipment.

This is probably cool but the alu that comes out is going to be terrible. a tragedy about recycling is how even the grade/alloy of Ali in the sides of a Ali can is different from the lid and they aren't compatible and it's still cheaper to smelt from ore than recycle cans because the resultant alloy is poo poo for anything. I think

echinopsis
Apr 13, 2004



College Slice

CarForumPoster posted:

It is steel. Alloys of steel can basically do everything they just do it heavier but from super alloys to corrosion resistance to very high strength to great machinability steel pretty much owns.

the correct answer was "thrash", nice one newbie


quote:

Oh then yea that is true in precip hardenable aluminum alloys, when the matrix itself is harder it is generally more machinable. Hence why machining stuff as cast suck rear end.
dude and you said what I said made no sense

CarForumPoster
Jun 26, 2013


rotor posted:

i didnt know

i mean, i knew some aluminums are better than others but given the source material i have (whatever crap I can scavenge from whereever) i just live with it.

I keep trying to find a machine shop that will let me dig through their scraps but this is SF and apparently there are no machine shops?!?

Cut up cast aluminum wheels. They'll be high silicon and suck rear end to machine afterward without aging, but you can prob age them in your home oven. I forget what the againg time and temps would be and can look them up tomorrow if you really want. P.S. moisture in castings is a very dangerous problem that also causes inclusions. Make sure your scrap is dry.


EDIT: Nevermind you said no home melting what a wuss/nice neighbor


EDIT2:

Call metal suppliers. Ask who sells drops. Go to their retail store where they sell drops. Be in home machinist heaven.

EDIT3:

Dont use a steel crucible by the way its super stupid cause with few exceptions Iron causes really brittle and makes lovely precipitates in aluminum and how lovely it is is a large part of why manganese is added to alloys.

CarForumPoster fucked around with this message at 03:37 on Oct 22, 2013

Sagebrush
Feb 26, 2012





Gravy Boat 2k

yeah a refractory crucible is where it's at. and frankly a small furnace suitable for melting small amounts of aluminum is really no more smoky and unpleasant than a gas grill, totally backyardable

echinopsis
Apr 13, 2004



College Slice

Zhentar
Sep 28, 2003

Brilliant Master Genius


echinopsis posted:

a tragedy about recycling is how even the grade/alloy of Ali in the sides of a Ali can is different from the lid and they aren't compatible and it's still cheaper to smelt from ore than recycle cans because the resultant alloy is poo poo for anything. I think

Incorrect (partially). You can mix in more magnesium, or more virgin aluminum, and end up with something that's suitable for the sides or lid. It's not very convenient, but refining aluminum from ore is very energy intensive, so it ends up being worth it anyway.

CarForumPoster
Jun 26, 2013


Zhentar posted:

Incorrect (partially). You can mix in more magnesium, or more virgin aluminum, and end up with something that's suitable for the sides or lid. It's not very convenient, but refining aluminum from ore is very energy intensive, so it ends up being worth it anyway.

Hes correct in that you shouldnt try to melt your own aluminum cans. No one was suggesting that one should. Melting aluminum cans at home though has all of the problems. 100% of possible problems.

SoundMonkey
Apr 22, 2006

I just push buttons.


Hey now chillun that's enough yospostin' in the capitalization bastion that is DIY (& Hobbies!)

JawnV6
Jul 4, 2004

So hot ...

rotor posted:

I keep trying to find a machine shop that will let me dig through their scraps but this is SF and apparently there are no machine shops?!?

We found multiple companies going through our trash. Not just people looking for recycleables, other professionals with office space nearby. If someone called up asking about trash pretty sure we'd deny having a machine shop too.

oxbrain
Aug 18, 2005

Put a glide in your stride and a dip in your hip and come on up to the mothership.


Don't waste time with machine shops, call metal recyclers and ask them if you can buy scrap metal. It'll be way cheaper than buying new, but you won't know what alloy you're getting if that matters.

gently caress any aluminum that isn't 6000 or 7000 series.

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


oxbrain posted:

Don't waste time with machine shops, call metal recyclers and ask them if you can buy scrap metal. It'll be way cheaper than buying new, but you won't know what alloy you're getting if that matters.

gently caress any aluminum that isn't 6000 or 7000 series.

i have but they dont want to sell me ingots, they want to sell me bundles of crushed trash and cars and stuff

Jonny 290
May 5, 2005

[A]sk me about OS/2 WARP


For scrap, maybe see if there are some engine/transmission/machine shops out by where the cabin is. Next time you roll out there, stop by a place or two, see if you don't have better luck with the ol' toothless boys in the hills.

mafoose
Oct 30, 2006

volvos and dogs and volvos and dogs and volvos and dogs and volvos and dogs and vulvas and dogs and volvos and dogs and volvos and dogs and volvos and dongs and volvos and dons and volvos and dogs and volvos and cats and volvos and dogs and volvos and dogs and volvos and dogs and volvos and dogs


rotor posted:

i have but they dont want to sell me ingots, they want to sell me bundles of crushed trash and cars and stuff

You need to try different metal recyclers, like the ones that work with construction companies.
Worst case scenario, a metal supplier. There should be lots, and most sell remnants for $1-2/lb or so over scrap. Here I have Industrial Metal Supply. They have a whole room of aluminum remnants, that sell for like $2-3/lb.

Try this place perhaps?
http://www.bayshoremetals.com/aluminum.htm
(ugh flash + music)

If you plan on making parts, you need to know what aluminum alloy you'll be using. You don't want to be using scrap of unknown source.

Oversimplification:
5052 for parts that get bent, or don't require lots of rigidity (try to bend with the grain to avoid cracks). It's also pretty inexpensive.
6061 for a good mix of strength/lb that won't break the bank. Most "billet" parts are made with this. You can bend certain tempers (T0, T4) pretty easily, but unless it's a big radius, 6061-T6 will crack if you try to bend it.
7075 is the most common "super strong" alloy. It's pretty awesome, but it is aerospace ($$$) and unweldable.

Avoid cast aluminum for structural parts, as it is usually much weaker than 6061. Cast jig plate is nice and flat and good for making fixtures though.

Material comes in basic shapes:
Sheet (thin)
Plate (thicker than sheet, can't remember what the cutoff is, something like >3/8" or so)
Bar (best for smaller parts, this is usually what I buy, because I can easily cut it with a chop saw or band saw to load in my machine)
Rod (solid)
Tube (hollow)
Angle, Channel, Beam (usually for structural parts, I like using angle and channel for parts that require 90deg bends, you can usually get them with sharp or round corners)

You really shouldn't be using ingots, as they aren't very uniform and might be hard to hold down to.

Also, you want to invest in proper tooling. Router bits are not replacements for proper endmills. Avoid 4 flute endmills on aluminum. 3 fluters work amazing, but 2 flutes cutters are substantially cheaper, and work almost as good. High spindle speeds, low depths of cut and high IPM are your friends on these non-rigid machines.

Have fun making chips!

CarForumPoster
Jun 26, 2013


Agree with most of what is above adding to it, 10-30% step over since you probably have no spindle power. Carbide endmills can be fed around 1% of diameter per tooth.

rotor
Jun 11, 2001

Official Carrier
of the Neil Bush Torch

 
 
 
 
teh butts


mafoose posted:

You need to try different metal recyclers, like the ones that work with construction companies.
Worst case scenario, a metal supplier. There should be lots, and most sell remnants for $1-2/lb or so over scrap. Here I have Industrial Metal Supply. They have a whole room of aluminum remnants, that sell for like $2-3/lb.

Try this place perhaps?
http://www.bayshoremetals.com/aluminum.htm
(ugh flash + music)

If you plan on making parts, you need to know what aluminum alloy you'll be using. You don't want to be using scrap of unknown source.

Oversimplification:
5052 for parts that get bent, or don't require lots of rigidity (try to bend with the grain to avoid cracks). It's also pretty inexpensive.
6061 for a good mix of strength/lb that won't break the bank. Most "billet" parts are made with this. You can bend certain tempers (T0, T4) pretty easily, but unless it's a big radius, 6061-T6 will crack if you try to bend it.
7075 is the most common "super strong" alloy. It's pretty awesome, but it is aerospace ($$$) and unweldable.

Avoid cast aluminum for structural parts, as it is usually much weaker than 6061. Cast jig plate is nice and flat and good for making fixtures though.

Material comes in basic shapes:
Sheet (thin)
Plate (thicker than sheet, can't remember what the cutoff is, something like >3/8" or so)
Bar (best for smaller parts, this is usually what I buy, because I can easily cut it with a chop saw or band saw to load in my machine)
Rod (solid)
Tube (hollow)
Angle, Channel, Beam (usually for structural parts, I like using angle and channel for parts that require 90deg bends, you can usually get them with sharp or round corners)

You really shouldn't be using ingots, as they aren't very uniform and might be hard to hold down to.

Also, you want to invest in proper tooling. Router bits are not replacements for proper endmills. Avoid 4 flute endmills on aluminum. 3 fluters work amazing, but 2 flutes cutters are substantially cheaper, and work almost as good. High spindle speeds, low depths of cut and high IPM are your friends on these non-rigid machines.

Have fun making chips!



this is really super useful to me and that bayshore metals place is kinda sorta on my way home. Thanks a lot!

echinopsis
Apr 13, 2004



College Slice

CarForumPoster posted:

Agree with most of what is above adding to it, 10-30% step over since you probably have no spindle power. Carbide endmills can be fed around 1% of diameter per tooth.

As a person whose job it was to cut alloy for over 6 years this makes no sense

Blistex
Oct 30, 2003
Probation
Can't post for 46 hours!


Grimey Drawer

Sounds like there are a lot of aluminum shavings in people's undies in this thread.

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CarForumPoster
Jun 26, 2013


echinopsis posted:

As a person whose job it was to cut alloy for over 6 years this makes no sense

I shall explain it then. 1% of cutter diameter per tooth is a good rule-of-thumb starting feed rate for milling aluminum.

Power consumption is essentially a function of MRR and the way to decrease your cutter load effectively is to use constant cutter engagement angles. You don't want to run the cutter on center line nor do you want to slot if you can avoid it so your "good" cutter step over ranges tend to be 10-35%, 65-85% with the ideal being 70%. With <50% you get chip thinning effects and should increase feed but on your baby mill at 1% cutter/tooth (e.g. a 1/4" cutter would be fed at .0025/tooth or for a 2 flute .005/rev) you'll be ok staying in the 10-30% step over range even if your effective cutting thickness isn't the full 1%.

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