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Karia
Mar 27, 2013

Self-portrait, Snake on a Plane
Oil painting, c. 1482-1484
Leonardo DaVinci (1452-1591)



College Slice

It's not really a question of "can it mill aluminum" as much as "how fast can it mill aluminum." You can cut pretty much any material on any machine, it'll just be really slow, and you'll really need to know what you're doing. On small or router-style machines, you'll need to use smaller tools, smaller depths of cut, and smaller stepovers. What sort of plate thickness are you wanting to machine, how much material do you want to remove, and what sort of tolerances are you trying to hit?

HolHorsejob posted:

I'd be interested to see it if you succeed. I've cut a fair bit of aluminum on an othermill, but never a larger router. The table I did/kinda do have access to (arcpro 9600 plasma table w/ router kit) performed well on wood, but cutting aluminum on it sounds like a bad idea. Maybe I should give it a shot though, now that I have more time on my hands.

How do you avoid work hardening or burning up the tool/workpiece? A constant mist of isopropanol?

Use a carbide tool. Aluminum doesn't really work-harden, either (maybe some weird alloys, but not 6061, that stuff's really easy to cut.) Chip evacuation is going to be the bigger issue on a router at high speed, and that can be settled with a shopvac or airblast (though be careful with the hot chips if you're vacuuming them into wood dust.)

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Ambihelical Hexnut
Aug 5, 2008


Here is how my dumb dumb brain thinks of it:

Hobby gantry routers are designed to cut woods, plastics, and other sheet goods. Because of this they typically have very large travels and comparatively low rigidity (compared to a mill design), very high speed spindles (20-30k RPM or so), and are designed around bits generally .25" in diameter or smaller. This is a weird combination for metal cutting, where slicing off a chip of just the right size is important for removing heat and having a good finish.

If a tool of 1/8" diameter should carry a chip load per tooth of .003" for aluminum, I can put that tool in my mill with a 2500RPM spindle and use a feed rate of 15 inches per minute to get the desired tooth load.

If I take that same 1/8" tool and put it in my router, which has a 26000RPM spindle, then in order to get the same chip load I'd need to move at a feed rate of 156 inches per minute. Because the spindle spins over 10 times faster, each time one flute on the tool comes around to take a scoop there's no material left for it to eat. The machine then has to move 10 times faster in order to keep the flutes fed at the same rate, but since the gantry router has very large travels and is comparatively flimsy (V wheels on aluminum extrusion over long distance vs. mill ways) it can't reliably accelerate and move fast enough to keep the flutes fed. At it's slowest speed, the trim router spindle is still 5X faster than the fastest speed of the mill spindle.

This results in lots of heat, poor cutting, poor finishes compared to doing the same op on a mill. Now add on top of that that your router, being designed around sheet wood cutting, is not generally super happy with liquid coolant being sprayed everywhere, and you get aluminum chips melting into and fixing themselves to your bit and eventual tool snappage.

TLDR: I cut thin aluminum sheet with my hobby router sometimes. It works, but is not great. With a new, sharp tool you will produce some okay parts and lots of aluminum dust and probably ruin your mdf spoilboard.

shovelbum
Oct 21, 2010



Fallen Rib

I think a lot of the Chinese cnc sheet goods routers have much more controllable and powerful spindles, right? Still not very rigid at all though

Ambihelical Hexnut
Aug 5, 2008


Controllable and powerful VFD spindles, yes. Able to produce power at low enough RPM to bring feeds into a reasonable range? I think even the 2.2/2.5kw spindles can only go down to 6k or 8k RPM. So if you're using really small tools and scooting around fast...

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull

If you look around hard enough, there are some Chinese brushless spindles that are setup to go slower, in the range of mill speeds. They're comparatively expensive though.

Methylethylaldehyde
Oct 23, 2004

BAKA BAKA


Ambihelical Hexnut posted:

If a tool of 1/8" diameter should carry a chip load per tooth of .003" for aluminum, I can put that tool in my mill with a 25000RPM spindle and use a feed rate of 150 inches per minute to get the desired tooth load.

This results in lots of heat, poor cutting, poor finishes compared to doing the same op on a mill. Now add on top of that that your router, being designed around sheet wood cutting, is not generally super happy with liquid coolant being sprayed everywhere, and you get aluminum chips melting into and fixing themselves to your bit and eventual tool snappage.

TLDR: I cut thin aluminum sheet with my hobby router sometimes. It works, but is not great. With a new, sharp tool you will produce some okay parts and lots of aluminum dust and probably ruin your mdf spoilboard.

Aluminum on a gantry router is at best a 'yes, if I REALLY have to' tier. You can totally do it, but good christ it's like using a butter knife to saw through a tree. You can make it work, but it'll take forever, look like poo poo, and you'll probably end up using a few knives to get it done.

On even a tormach 440, you can cut basically anything you like, because it has enough low end torque and enough feed rate, and just enough rigidity to get you what you want done, reasonably quickly.

Ambihelical Hexnut
Aug 5, 2008


Ambihelical Hexnut posted:



My CNC LMS 3990 sat dormant this winter. I've got most of what I need to make a plastic "enclosure" just to contain chips, but have yet to bring the whole plan together. I also have apprehension because it continues to be plagued by random e-stops picked up in the gecko controller and I have no fuckin idea how to make any progress on that. This issue has really made me resent the G540, even though it's probably my fault. I need to draw up a new stand and the enclosure, figure out how to extend the stepper wires, and then get off my rear end and actually build some metal poo poo.

Did some more digging and paid some hard dollars to replacing wiring between the USB Smoothstepper and the G540, the G540 and steppers, and rewire the USB-SS for external 5V power. The mill has now gone through several hours of shakedown without a single estop poppin up. Canít believe this took me so long to resolve.

I also have been trying to learn welding by sticking together some square tubing to construct a mill stand. Itís going...slowly.

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull

How much of a pain was the LMS 3990 to convert? I'm really tempted to use that to learn some stuff until I get a shop built with 3 phase.

Ambihelical Hexnut
Aug 5, 2008


I bought it converted from a dude who upgraded to a 1990-vintage VMC. The mechanical conversion is relatively simple, as far as I can tell, and only involved tapping a couple holes.

The things I had to do for usability's sake were upgrading way covers, adding limit switches and brackets, and moving the electronics from a sheet of plastic open to the world to an enclosure. Plus the aforementioned cable changes as the stepper cables he installed are like 24 inches long which severely limits where the electronics can be and were causing troubles.

HolHorsejob
Mar 13, 2020

In the land of Hyrule, there echoes a legend. A legend held dearly by the Royal Family tells of a boy... A boy who, after battling evil and saving Hyrule, crept away from the land that made him a legend... Done with the battles he once waged across time, he embarked on a journey...


Ambihelical Hexnut posted:

Did some more digging and paid some hard dollars to replacing wiring between the USB Smoothstepper and the G540, the G540 and steppers, and rewire the USB-SS for external 5V power. The mill has now gone through several hours of shakedown without a single estop poppin up. Canít believe this took me so long to resolve.

I also have been trying to learn welding by sticking together some square tubing to construct a mill stand. Itís going...slowly.

How is the usb smoothstepper? What's the interface like for that? I have a friend that initially set up her taig with a TinyG and had generally poor results (buffer/throughput issues, non-rt control), which, from what I understand, were primarily a limitation of using USB to send steps.

E: she was also using Chilipeppr as the interface, which added its own little pocket hell to the experience.

EE: got pics? Would love to see it

HolHorsejob fucked around with this message at 19:00 on May 1, 2020

Ambihelical Hexnut
Aug 5, 2008


Well until the rewiring which apparently fixed everything I would've said the USB-SS and Gecko 540 combination was annoying and flaky compared to all the other CNC tools I've used. I am a bit flabbergasted at how perfectly it seems to operate now, but all the required changes are well documented in manuals I should've read closer over the years: separate 5v power supply for USB-SS; parallel port extension cable to get the USB-SS away from the G540; better stepper cables with properly done shielding/etc.

The USB-SS is basically invisible from my user perspective. The driver runs, mach3 outputs over USB, the SS poops it out via parallel cable to the G540.

Here it is mid fix:


I had to mount my electronics enclosure on the wall due to the old short stepper cables. The G540 is inside the box with a power supply, the USB-SS is that board clipped to the outside. I'm tearing that bench apart currently and have welded the jankiest loving stand ever out of 1.25" square tubing. It's my hope that I can use the sheet of corrugated plastic board I bought to enclose the chip and coolant spray mess, even partially, as it really makes the mill annoying to use. Note my XBox controller as mach3 jog pendant which is the best poo poo ever.

The real key to usability on this thing is going to be figuring out a power drawbar. I started milling pieces for one a couple years ago but all milling projects have been on hold for a while.

Here's a vid I posted a couple years ago: https://www.youtube.com/watch?v=hrMSqOKHR-k

Before the first and second corners it's got a good chipload going. The stock was input incorrectly and after the second corner and beyond it took on way too deep of a cut, leaving a lovely finish but still chugging through like it was no big deal.

Ambihelical Hexnut fucked around with this message at 02:14 on May 2, 2020

mekilljoydammit
Jan 28, 2016

Me have motors that scream to 10,000rpm. Me have more cars than Pick and Pull

That looks good enough to do a lot of things that I want to do. I may have to save my pennies.

EvilBeard
Apr 24, 2003

Big Q's House of Pancakes



Fun Shoe

I've been looking at getting a PM-25MV and then converting it using the Centroid Acorn system. I thought about going whole hog and buying an old bridgeport and converting it, but right now floor space in my garage is the real limiting factor. I'll just go the benchtop route and then work my way up to a bigger machine if needed. I'd love to add garage/shop space eventually.

Ambihelical Hexnut
Aug 5, 2008


Are you converting because you want the experience of doing it? If not, depending on where your budget lies, you might save money buying someone else's working conversion. I don't know about PM-25MVs but I've seen a lot of converted Taigs (100lbs, $1.5-2k) and Grizzlys (375lbs, $3-4k) for sale over the years from people stepping up. If you start with a $2k manual mill it would be easy for a conversion to chew up another 2-3k over time. Once you approach $5-6k you're getting near the base machine cost for a new Tormach 440 which is probably the heaviest "benchtop" sized mill in hobby use.

I am probably about $2k into my mill not counting any consumables, and it's on the small end of the spectrum.

EvilBeard
Apr 24, 2003

Big Q's House of Pancakes



Fun Shoe

Ambihelical Hexnut posted:

Are you converting because you want the experience of doing it? If not, depending on where your budget lies, you might save money buying someone else's working conversion. I don't know about PM-25MVs but I've seen a lot of converted Taigs (100lbs, $1.5-2k) and Grizzlys (375lbs, $3-4k) for sale over the years from people stepping up. If you start with a $2k manual mill it would be easy for a conversion to chew up another 2-3k over time. Once you approach $5-6k you're getting near the base machine cost for a new Tormach 440 which is probably the heaviest "benchtop" sized mill in hobby use.

I am probably about $2k into my mill not counting any consumables, and it's on the small end of the spectrum.

I'm an industrial maintenance tech. I deal with these systems or similar systems nearly all day. I know what it's going to take. It looks to be around $4.5k to convert a manual mill, and some tooling. I could get a used one, but at that point, I could be inheriting someone else's shoddy work or cut corners. If I get one new, I know what's been done, and I can be happy with the work that's been done. It's mainly that peace of mind that I'm willing to shell out for.

CarForumPoster
Jun 26, 2013


Ambihelical Hexnut posted:

Did some more digging and paid some hard dollars to replacing wiring between the USB Smoothstepper and the G540, the G540 and steppers, and rewire the USB-SS for external 5V power. The mill has now gone through several hours of shakedown without a single estop poppin up. Canít believe this took me so long to resolve.

I also have been trying to learn welding by sticking together some square tubing to construct a mill stand. Itís going...slowly.

As a heads up using twisted shielded pair with a properly grounded shield and connector as well as separate power wires not run right next to your signal wires are a pretty standard "I'm getting anomalous triggers" EMI/EMC issue.
Particularly with CNC machines you have basically every factor for EMI/EMC issues:
-VFDs
-welders and plasma cutters nearby and sharing a common ground
-Physically running noisy wires with low voltage signal wires in the same loom.
-Long, sometimes beyond spec, digital signal wire cable runs.
-Rubbing of wires causing damage to shielding.
-Bad/No grounding of shields.
-Old or cheap high current motors with old/cheap wiring.
-Shoddy electronics with dubious impedance matching.

Here:s a laymans presentation of issues if you havent built the system yet, buying the right stuff goes a long way:
https://www.cnccookbook.com/cnc-ele...ference-filter/

CarForumPoster fucked around with this message at 22:22 on May 3, 2020

HolHorsejob
Mar 13, 2020

In the land of Hyrule, there echoes a legend. A legend held dearly by the Royal Family tells of a boy... A boy who, after battling evil and saving Hyrule, crept away from the land that made him a legend... Done with the battles he once waged across time, he embarked on a journey...


CarForumPoster posted:

As a heads up using twisted shielded pair with a properly grounded shield and connector as well as separate power wires not run right next to your signal wires are a pretty standard "I'm getting anomalous triggers" EMI/EMC issue.
Particularly with CNC machines you have basically every factor for EMI/EMC issues:
-VFDs
-welders and plasma cutters nearby and sharing a common ground
-Physically running noisy wires with low voltage signal wires in the same loom.
-Long, sometimes beyond spec, digital signal wire cable runs.
-Rubbing of wires causing damage to shielding.
-Bad/No grounding of shields.
-Old or cheap high current motors with old/cheap wiring.
-Shoddy electronics with dubious impedance matching.

Here:s a laymans presentation of issues if you havent built the system yet, buying the right stuff goes a long way:
https://www.cnccookbook.com/cnc-ele...ference-filter/

Thanks for the link. So are you saying that the grounded shielding + separate power wires away from signal wires causes EMI issues, or alleviates them?

My Taig mill project is currently stalled while I get my space ready for mounting it, but once that's squared away, I'm going to set up/wire up the limit switches. I was originally thinking of wiring the switches to a DB9 socket mounted to the frame and just use a cable to connect them, but now I'm having second thoughts. I do have some 8-conductor double-shielded wiring I got surplus from some robotics work. Don't think it's twisted pair though.

Ambihelical Hexnut
Aug 5, 2008


CarForumPoster posted:

As a heads up using twisted shielded pair with a properly grounded shield and connector as well as separate power wires not run right next to your signal wires are a pretty standard "I'm getting anomalous triggers" EMI/EMC issue.
Particularly with CNC machines you have basically every factor for EMI/EMC issues:
-VFDs
-welders and plasma cutters nearby and sharing a common ground
-Physically running noisy wires with low voltage signal wires in the same loom.
-Long, sometimes beyond spec, digital signal wire cable runs.
-Rubbing of wires causing damage to shielding.
-Bad/No grounding of shields.
-Old or cheap high current motors with old/cheap wiring.
-Shoddy electronics with dubious impedance matching.

Here:s a laymans presentation of issues if you havent built the system yet, buying the right stuff goes a long way:
https://www.cnccookbook.com/cnc-ele...ference-filter/

Thanks. I did a lot of that troubelshooting, including separating wires, twisted shielded pairs, magnetic ferrule doo-dads on my cables. What I didn't do was: chase down the stepper cables (because these were hard wired into the motors and covered in loom cover so I assumed them good, or remove the USB-SS from the enclosure and ensure it was grounded/powered separately.

Tim Thomas
Feb 12, 2008
breakdancin the night away

Iím going to see if I can ferret out whether the 3040/6040 aluminum and steel cutting (!!!) performance is due more to flimsiness or if itís due to cutting parameters being bonkers. I found a half decent spindle and I have a kw servo motor kicking around, so I should be able to run way waaaaay lower rpms. Iíve stiffened the bed via backside support and 38mm of ply spoilboard, and I have a different rigid design for the gantry since it wants to flex in X since it isnít supported, but I want to see how chowdery it is first.

CarForumPoster
Jun 26, 2013


HolHorsejob posted:

the grounded shielding + separate power wires away from signal wires causes EMI issues, or alleviates them?

My Taig mill project is currently stalled while I get my space ready for mounting it, but once that's squared away, I'm going to set up/wire up the limit switches. I was originally thinking of wiring the switches to a DB9 socket mounted to the frame and just use a cable to connect them, but now I'm having second thoughts. I do have some 8-conductor double-shielded wiring I got surplus from some robotics work. Don't think it's twisted pair though.

In general, alleviates. Also, shielding should always be grounded.

Ambrose Burnside
Aug 29, 2007

pensive


HolHorsejob posted:

Thanks for the link. So are you saying that the grounded shielding + separate power wires away from signal wires causes EMI issues, or alleviates them?

My Taig mill project is currently stalled while I get my space ready for mounting it, but once that's squared away, I'm going to set up/wire up the limit switches. I was originally thinking of wiring the switches to a DB9 socket mounted to the frame and just use a cable to connect them, but now I'm having second thoughts. I do have some 8-conductor double-shielded wiring I got surplus from some robotics work. Don't think it's twisted pair though.

Another Taig owner, nice. What sort of setup/CNC conversion are you going with?

HolHorsejob
Mar 13, 2020

In the land of Hyrule, there echoes a legend. A legend held dearly by the Royal Family tells of a boy... A boy who, after battling evil and saving Hyrule, crept away from the land that made him a legend... Done with the battles he once waged across time, he embarked on a journey...


Ambrose Burnside posted:

Another Taig owner, nice. What sort of setup/CNC conversion are you going with?

Don't know what the mill was purchased as, but it was halfway through a CNC conversion when I got it. It was most likely shipped CNC-ready at least 5 years ago.

I'm doing a gecko/LinuxCNC setup. It's currently languishing at my place while I try to figure out how to make space for it and build a stand. I've got the control & electronics built and tested, current to-do list is:

1. Clear some space and build a bench to attach it to
2. Mount/hook up limit switches
3. Tweak/tune all of the hardware & software


Was gonna do a ballscrew conversion but have found myself newly unemployed, so maybe another time. I guess 40 in/min will have to do for the time being.

Piss Meridian
Mar 25, 2020


CarForumPoster posted:

In general, alleviates. Also, shielding should always be grounded.

Ground noise vulnerable (signal) shielding at the mcu end, ground noise generating cables (motor drivers etc) at both ends

Ambrose Burnside
Aug 29, 2007

pensive


HolHorsejob posted:

Don't know what the mill was purchased as, but it was halfway through a CNC conversion when I got it. It was most likely shipped CNC-ready at least 5 years ago.

I'm doing a gecko/LinuxCNC setup. It's currently languishing at my place while I try to figure out how to make space for it and build a stand. I've got the control & electronics built and tested, current to-do list is:

1. Clear some space and build a bench to attach it to
2. Mount/hook up limit switches
3. Tweak/tune all of the hardware & software


Was gonna do a ballscrew conversion but have found myself newly unemployed, so maybe another time. I guess 40 in/min will have to do for the time being.

Sweet, thatís a smart way to get started. Do you have any particular sort of work you wanna do with it?

And yeah, ballscrews come universally recommended. tiny ďrealĒ metal milling-oriented CNC mills like the Taig benefit to an exaggerated degree because travel speed becomes the primary bottleneck for part run times when using the high speed machining toolpaths favoured by the smallest mills (limited by thin+flexible tooling, high spindle RPMs and low-rigidity columns). I donít have em on my mill but iirc they can singlehandedly reduce run times for marathon tasks like extensive 3D contouring by 50%+

Ambrose Burnside fucked around with this message at 23:53 on May 5, 2020

Ambihelical Hexnut
Aug 5, 2008




Now that the mill kinda works it's time to drown in another project: I am quietly piling up steel and extrusion in the garage to get a larger gantry going with the intent of being a budget plasma table. CNCRP rack and pinion drives and linear carriages. My plan is basically to make a relatively lightweight gantry from 2x4" and 2x2" extrusion, reinforced by the 3" steel flatbar and gear rack for the linear motion system. 3x3" and 3x2" 11ga steel tube will make the table frame easy enough. This is a way cheaper approach than using nice linear rails, but has been demonstrated successfully online many times.

Immediate problems to solve- drilling parallel rows of holes down the flat bar for t-nuts, milling/welding gantry riser plates, figuring out a cheaper way to get/make a water table than buying a prefab.

Ambihelical Hexnut
Aug 5, 2008


Okay so how will I get parallel 1/4Ē holes drilled precisely down the length of a 72Ē bar? The hole spacing from the bar end and from each adjacent hole is relatively critical, as is the parallelism of each row of holes to the edge of the bar. The spacing of each hole down the length of the bar is not critical, so hereís the solution: use my tiny mill to drill two (or maybe 4-6) precisely spaced holes inside the table/vise limits, then slide the bar down, clamp and repeat. I can use my linear carriages as as an improvised roller to bare the weight of the unsecured ends of the bar. I should be able to indicate off the free bar edge in two places to determine straightness of the mount. Test setup:





Iíll need to think about this some more before ruining the first piece of stock.

biracial bear for uncut
Jun 9, 2009

ask me about being the most obnoxious person of all time

Ambihelical Hexnut posted:

Okay so how will I get parallel 1/4Ē holes drilled precisely down the length of a 72Ē bar? The hole spacing from the bar end and from each adjacent hole is relatively critical, as is the parallelism of each row of holes to the edge of the bar. The spacing of each hole down the length of the bar is not critical, so hereís the solution: use my tiny mill to drill two (or maybe 4-6) precisely spaced holes inside the table/vise limits, then slide the bar down, clamp and repeat. I can use my linear carriages as as an improvised roller to bare the weight of the unsecured ends of the bar. I should be able to indicate off the free bar edge in two places to determine straightness of the mount. Test setup:





Iíll need to think about this some more before ruining the first piece of stock.

You can use your last hole in one setup as your first alignment hole when moving setups. Maybe one program working off one edge datum, then the sequential programs basically calling X/Y zero the hole you locate off of in the subsequent setups.

As long as you don't loosen the vise bolts on the table you won't have to worry much about parallelism as you reset X on subsequent setups.

If you have some manual machining experience this should be easy to do, all you're doing is using the CNC controller to do a series of holes more rapidly than you can do it manually.

biracial bear for uncut fucked around with this message at 18:07 on May 14, 2020

gonadic io
Feb 16, 2011

>>=


I have a weird shaped table and so need a custom bracket plate. It's basically just a metal rectangle on half inch steel, with some holes drilled, and a 90 degree horizontal fold half way down.

I was thinking about buying a 1-off cnc job for it, what program would people recommend for basic programs to put something together that I could send to a company? Most of them seem to cost 2k+ and sadly I am not a student.

I mean, or I could buy my first drill press and router and start down the slippery slope...

sharkytm
Oct 9, 2003

Gimme Gimme Swedish Fish...

Fallen Rib

gonadic io posted:

I have a weird shaped table and so need a custom bracket plate. It's basically just a metal rectangle on half inch steel, with some holes drilled, and a 90 degree horizontal fold half way down.

I was thinking about buying a 1-off cnc job for it, what program would people recommend for basic programs to put something together that I could send to a company? Most of them seem to cost 2k+ and sadly I am not a student.

I mean, or I could buy my first drill press and router and start down the slippery slope...

Fusion360, or a sketch on a napkin and call your local fabrication shop.

HolHorsejob
Mar 13, 2020

In the land of Hyrule, there echoes a legend. A legend held dearly by the Royal Family tells of a boy... A boy who, after battling evil and saving Hyrule, crept away from the land that made him a legend... Done with the battles he once waged across time, he embarked on a journey...


gonadic io posted:

I have a weird shaped table and so need a custom bracket plate. It's basically just a metal rectangle on half inch steel, with some holes drilled, and a 90 degree horizontal fold half way down.

I was thinking about buying a 1-off cnc job for it, what program would people recommend for basic programs to put something together that I could send to a company? Most of them seem to cost 2k+ and sadly I am not a student.

I mean, or I could buy my first drill press and router and start down the slippery slope...

What's your experience level? Fusion 360 is a reasonable option. I was able to model parts, generate drawings and get parts manufactured (as long as the shop does not require GD&T for drawings).

What kind of tolerances does this part require? If it's half-mm tolerances and mill finish flatness, then a drill press, angle grinder/hacksaw, and bench grinder would get you there, as long as you have nice things like calipers and Dykem. I think I was able to get 0.015" tolerances on drill placement with these tools without too much trouble (over short lengths, anyways).

shovelbum
Oct 21, 2010



Fallen Rib

gonadic io posted:

I have a weird shaped table and so need a custom bracket plate. It's basically just a metal rectangle on half inch steel, with some holes drilled, and a 90 degree horizontal fold half way down.

I was thinking about buying a 1-off cnc job for it, what program would people recommend for basic programs to put something together that I could send to a company? Most of them seem to cost 2k+ and sadly I am not a student.

I mean, or I could buy my first drill press and router and start down the slippery slope...

Like half inch thick steel plate? What is this table for, your elephant collection?

gonadic io
Feb 16, 2011

>>=


It's for a monitor arm stand, so it potentially has to hold a good amount of weight in a reasonably small area. I got my calipers that I bought for this out and turns out that the part I want to recreate but bigger is actually quarter-inch, NOT half-inch and I'm just bad at estimating sizes from memory.

Doing it myself with a grinder and a drill press is probably absolutely possible too, but seems easier and cheaper overall to just get it made once instead of buying a bunch of gear.

shovelbum
Oct 21, 2010



Fallen Rib

sharkytm posted:

Fusion360, or a sketch on a napkin and call your local fabrication shop.

Yeah this sounds more like a job for a random welding/fab kind of shop, having it machined seems super expensive for what it sounds like this kind of thing is.

HolHorsejob
Mar 13, 2020

In the land of Hyrule, there echoes a legend. A legend held dearly by the Royal Family tells of a boy... A boy who, after battling evil and saving Hyrule, crept away from the land that made him a legend... Done with the battles he once waged across time, he embarked on a journey...


gonadic io posted:

It's for a monitor arm stand, so it potentially has to hold a good amount of weight in a reasonably small area. I got my calipers that I bought for this out and turns out that the part I want to recreate but bigger is actually quarter-inch, NOT half-inch and I'm just bad at estimating sizes from memory.

Doing it myself with a grinder and a drill press is probably absolutely possible too, but seems easier and cheaper overall to just get it made once instead of buying a bunch of gear.

So something like a 6x6 or 8x8 steel plate with a pattern of holes drilled into it, bolted to a tabletop? If it were me, I'd use probably 12-14 gauge steel, mark everything out with calipers, and do everything with a hand drill, angle grinder, and a few cheap hand files to debur and clean up the edges. If I had more projects lined up and thought I'd realistically get use out of them, I'd get a drill press and bench grinder.

I don't know much about getting small jobs done by a shop, but it sounds like it'd either be too expensive to be worth your while, or too cheap to be worth their while.

Karia
Mar 27, 2013

Self-portrait, Snake on a Plane
Oil painting, c. 1482-1484
Leonardo DaVinci (1452-1591)



College Slice

biracial bear for uncut posted:

You can use your last hole in one setup as your first alignment hole when moving setups. Maybe one program working off one edge datum, then the sequential programs basically calling X/Y zero the hole you locate off of in the subsequent setups.

As long as you don't loosen the vise bolts on the table you won't have to worry much about parallelism as you reset X on subsequent setups.

If you have some manual machining experience this should be easy to do, all you're doing is using the CNC controller to do a series of holes more rapidly than you can do it manually.

Rather than indicating in the hole every time you move, you can keep your drillbit down in the hole (plunged down past the flutes so the shank is in the hole), unclamp, and use the X axis to drag the bar over. You'll probably lose a thou or two every time because the hole's going to be slightly oversize, but maybe that's acceptable, and once you know that offset you can compensate for it if you want.

gonadic io
Feb 16, 2011

>>=


Oh I forgot you could just do this locally. I guess I was biased by e.g. internet based PCB manufacturing. Yeah that's 1000% easier.

HolHorsejob posted:

So something like a 6x6 or 8x8 steel plate with a pattern of holes drilled into it, bolted to a tabletop? If it were me, I'd use probably 12-14 gauge steel, mark everything out with calipers, and do everything with a hand drill, angle grinder, and a few cheap hand files to debur and clean up the edges. If I had more projects lined up and thought I'd realistically get use out of them, I'd get a drill press and bench grinder.

I don't know much about getting small jobs done by a shop, but it sounds like it'd either be too expensive to be worth your while, or too cheap to be worth their while.

The main thing stopping me from doing this is that I'd also need a bender, or machine from a 6x6x6 inch block and grind away 5.75x5.75x6 inches of it.

edit: there's a place near me that specifies barbecue grills as something they specifically do, so this doesn't really sound too small for them. 1 man with welder is the kind of level I was looking for.

gonadic io fucked around with this message at 22:52 on May 15, 2020

Sagebrush
Feb 26, 2012





Gravy Boat 2k

Steel up to a quarter inch thick you can bend in a vise with a hammer.

honda whisperer
Mar 29, 2009



You got a rough sketch of what you're trying to do?

gonadic io
Feb 16, 2011

>>=


Let me just get my napkin

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gonadic io
Feb 16, 2011

>>=


Here I whipped out the virtual equivalent of a napkin, and also the best cad software on my computer:

There's a pretty big skirt on the edge of my table, I have been totally unable to find any monitor clamp that would fit around it, and I'm not drilling a hole into my table for this.

The top part that was provided with the clamp seems mostly fine, it has a vertical line of 4 nut and bolt holes to secure the two together.

e: actually maybe I want the top bit bigger, to put the axis of the actual stand inline with the clamp on the bottom

gonadic io fucked around with this message at 00:54 on May 16, 2020

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