Re: A poor mans CNC machine
Thanks, Ive been keeping various parts through out the years for this new design (as I ditched the old) and if it has major problems I just might have to order parts to get it finished.
https://i.imgur.com/zW52U9S.jpg
https://i.imgur.com/JTHCNrG.jpg
My youtube channel showing the extension I made for my van so that I can use it as a workshop.
https://www.youtube.com/user/VancityComputers/videos
Re: A poor mans CNC machine
I might mention that home centers suck when it comes to component costs. So not the best way to buy build materials, especially anything involving metal.
My laptop died so I will not be able to see much detail but it does look like your machine could use more thought in the bearings. Generally the cheaper the bearing solution the farther they need to be spread out.
Re: A poor mans CNC machine
For sure materials are expensive, even bolts and brackets. Ive used an Ikea bed for the X base, the metal supports are sourced from a bed board, and a ladder for the table.
Each wheel has two bearings so there are many... here is my Z axis and table design.
https://i.imgur.com/0YPiLUd.jpg
https://i.imgur.com/w3tARnY.jpg
https://i.imgur.com/SixldZw.jpg
Re: A poor mans CNC machine
Re: A poor mans CNC machine
Thanks, although the Y-axis is very stiff to move back and forth, Im getting lots of flexing.
Im not sure if some ad-on bracing will fix this, maybe centering all the wheels to the Y bar might help?
https://www.youtube.com/watch?v=t1gPuK82IB4
Re: A poor mans CNC machine
i realize that everyone's machines are a product of what they can afford, and material availability. i got a deal on my machine, due to pure luck i think.
i am concerned about the flex you mentioned. (haven't watched the videos yet.) maybe i missed it, but what is your end plan for this machine? what are you routing?
~Travis
Re: A poor mans CNC machine
I would like to transform the front of an old sports car into a new design by carving pink HomeDepot foam for the mold.
Im thinking of stacking some square tubing I have, inplace of the ladder braces Im using maybe to reduce flex seen in the video.
https://i.imgur.com/zpCyCfU.jpg
Re: A poor mans CNC machine
i haven't routed foam before, but i have cut it on a table-saw, and the foam tends to grab onto the saw blade, and bind up. when the foam is moving past the blade at a good rate, it is fine. but slow down, or stop, and bad things happen. if there is much flex at all, i can envision the router bit orbiting around in the foam. others with more foam routing experience may know better. i just wanted to voice my concerns.
i understand the whole low-budget build. before i just happened to catch the Craigslist advertisement, for my router table, i too was looking to use inexpensive materials. seemed like every design i came up with, i was told to build it stiffer and stronger. i had even setup an experiment, and tried to route a simple sign using a wood router, completely free-hand. the forces of the bit cutting into the material, and wanting to take off on it's own was surprising.
also, on the note of cutting foam. i know when i cut it on a table-saw, the foam "dust" gets absolutely everywhere, and sticks to everything. i would suggest thinking about some sort of dust collection. even a shop-vacuum should work, until it fills up. ;)
not trying to discourage you and your machine, just trying to pass on what little experience i have.
~Travis
Re: A poor mans CNC machine
There are special burrs for cutting foam. Dust will be a huge problem. Peter
Re: A poor mans CNC machine
Quote:
Originally Posted by
Arashb
For sure materials are expensive, even bolts and brackets.
Yes cost of materials for the shop or even the house is expensive, especially at home centers! There are alternatives though, here are some suggestions:
1. Tractor Supply is pretty good for quality bolts in the larger size and some machine screws. Great if you want to pick up some hardware and don’t want Togo on line.
2. McMaster-Carr has almost everything though you need to deal with ordering blind. By that I mean you might not be able to select a manufacture.
3. Suppliers to the metal working industries like MSC, Travers and etc. Probably more expensive but you can buy in bulk.
4. Supplier to electrical contractors like Horizon or whatever is local to you; can often beat hardware store prices.
5. Don’t forget the internet. Amazon and a whole host of businesses selling to the tool industry, over the net, can often be hard to beat.
Quote:
Ive used an Ikea bed for the X base, the metal supports are sourced from a bed board, and a ladder for the table.
Each wheel has two bearings so there are many... here is my Z axis and table design.
That might pass for foam. Anything tougher though might be a problem.
Re: A poor mans CNC machine
Great list.
The massive alluminum supports I have now are left overs from my father backyard fence. I also scored cheap plastic cutting boards for $3 Canadian at Ikea. Since I ended up using so many large skate wheels, these have been the bulk of the gantry costs.
Quote:
Originally Posted by
travis_farmer
i haven't routed foam before, but i have cut it on a table-saw, and the foam tends to grab onto the saw blade, and bind up. when the foam is moving past the blade at a good rate, it is fine. but slow down, or stop, and bad things happen. if there is much flex at all, i can envision the router bit orbiting around in the foam. others with more foam routing experience may know better. i just wanted to voice my concerns.
i understand the whole low-budget build. before i just happened to catch the Craigslist advertisement, for my router table, i too was looking to use inexpensive materials. seemed like every design i came up with, i was told to build it stiffer and stronger. i had even setup an experiment, and tried to route a simple sign using a wood router, completely free-hand. the forces of the bit cutting into the material, and wanting to take off on it's own was surprising.
also, on the note of cutting foam. i know when i cut it on a table-saw, the foam "dust" gets absolutely everywhere, and sticks to everything. i would suggest thinking about some sort of dust collection. even a shop-vacuum should work, until it fills up. ;)
not trying to discourage you and your machine, just trying to pass on what little experience i have.
~Travis
Thanks, I found a used bit made for cutting plastic eye glasses and it looks just right for foam... reading from others accounts. The brand is Gerber Optical.
https://i.imgur.com/a0vkjZT.jpg
I also decided to beef up my supports and now have a mini cnc machine to make some new linear rail too.
https://i.imgur.com/79j6acW.jpg
https://i.imgur.com/TqRev17.jpg
Quote:
Originally Posted by
peteeng
There are special burrs for cutting foam. Dust will be a huge problem. Peter
Im thinking of running the machine in my vans extension pull out, have it enclosed and if I cant vaccum the dust properly, just wash it off (being careful of electronics) to filter into a large bucket. Lots of toxic flame retardants and such in foam, will have to discard it properly.
https://i.imgur.com/qJiFLBQ.jpg
Re: A poor mans CNC machine
My mini 3018 CNC has a GRBL Controller board, chipset ch340
Im having problems with the Lightburn (I plan to make templates for my linear enclosure) program to get proper coordinates and scaling it looks like. To try and remedy this, Ive decided to put in some limit switches but dont know which of the 3 pins on the controller board I should connect the two wires coming off a switch... any guesses?
https://i.imgur.com/PGJYamN.jpg
Re: A poor mans CNC machine
Quote:
Originally Posted by
Arashb
Great list.
The massive alluminum supports I have now are left overs from my father backyard fence. I also scored cheap plastic cutting boards for $3 Canadian at Ikea. Since I ended up using so many large skate wheels, these have been the bulk of the gantry costs.
Thanks, I found a used bit made for cutting plastic eye glasses and it looks just right for foam... reading from others accounts. The brand is Gerber Optical.
https://i.imgur.com/a0vkjZT.jpg
I also decided to beef up my supports and now have a mini cnc machine to make some new linear rail too.
https://i.imgur.com/79j6acW.jpg
https://i.imgur.com/TqRev17.jpg
Im thinking of running the machine in my vans extension pull out, have it enclosed and if I cant vaccum the dust properly, just wash it off (being careful of electronics) to filter into a large bucket. Lots of toxic flame retardants and such in foam, will have to discard it properly.
https://i.imgur.com/qJiFLBQ.jpg
I don't think that small cross section beam across the gantry and the huge distance from it to the tool tip will be a happy combination.Even in a material as soft as foam the movement of the spindle may well induce some twisting.
Re: A poor mans CNC machine
Nice... with the massive supports I have, I didnt want to drill through with super long bolts and wanted to reach into the support opening at the top to fasten small bolts, but I think I'll change the design, thanks.
edit
Luckily after experimenting and smelling burnt electronics I didnt fry my board. One indication was the USB disconnect sound from the computer when shorting it.
I found the pins output by looking at the back of the board.
Also a similar schematic https://i.imgur.com/7naMUfR.jpg
https://i.imgur.com/bumi4qq.jpg
I ran these settings, limit switch COM to negative on the board, and NO to signal on the board. I used the program Universal G-Code Sender (machine, setup wizard, limit switches) to test each axes (had to hold down the switch rather then tap).
https://i.imgur.com/ZDcWEGs.jpg
Being a hoarder of junk, these 1 inch sticky mounts came in handy for placement. Used garden shears to shorten the plastic mounts.
https://i.imgur.com/8HFGWlJ.jpg
Re: A poor mans CNC machine
It was frustrating to get the working area of the Lightburn laser program to match my 3018 GRLB machine, heres what I did after installing limit switches.
(a video guide on limit switches)
3018 CNC/PRO - Limit/homing switches 3018 CNC/PRO - Limit/homing switches - YouTube
First I modified all the axis working areas to the CNC controller.
1) A) For example in the console I changed the X axis specs by writing; $110=300
Below are the codes for the other axis's.
$110, $111 and $112 – [X,Y,Z]
B) I think I added too this but it may not be needed
"$10=0 (this changes the position reporting to be in work coords, not machine coords)"
https://i.imgur.com/rcYTXy0.jpg
A sample of my current settings
Code:
$$
$0=10
$1=254
$2=0
$3=3
$4=0
$5=0
$6=1
$10=0
$11=0.010
$12=0.002
$13=0
$20=0
$21=1
$22=1
$23=3
$24=25.000
$25=500.000
$26=250
$27=5.000
$30=10000
$31=0
$32=0
$100=400.000
$101=400.000
$102=200.000
$110=5000.000
$111=5000.000
$112=600.000
$120=20.000
$121=20.000
$122=20.000
$130=300.000
$131=180.000
$132=40.000
ok
2) CNC settings are generally coded in the negative axis, we have to modify a file and upload it to the controller to put it in the positive axis.
A) Search your
users\xxxx\documents\arduino\libraries\
folder for the GRBL folder, also the librarie folder where you have arduino installed
cut and past this to the desktop, find the file config.h and open it with your Windows Notepad program
B)With the find feature, locate the following exact line (older versions of grbl have a different code) and delete it, and save the file with the same original extension (not ending with .txt)
Code:
// #define HOMING_FORCE_SET_ORIGIN // Uncomment to enable.
C) Run the Arduino program and setup/configure it to your machine. (remember we have should have deleted any previous GRBL folders from step A)
Under 'Sketch' and after 'Include Library' is where we find 'Add .ZIP Library', then only select the GRBL folder alone on the desktop where we modified that config.h file earlier.
D) Under 'File' and 'Examples', scroll the arrow to the bottom and locate 'GRBL', through there select grlbUpload
In the new window click the arrow icon to upload... ignore any errors.
Towards the end of this guide is how to initially install Ardruino and upload the GRBL drivers.
3018 CNC/PRO - New (updated) beginner's step by step guide - All tricks and tips
Quote:
youtu.be/fd07-OfCsAk?t=4723
After running Lightburn, I home the machine first in the absolute settings, the origin point at the far left and it should be all aligned. https://i.imgur.com/c22KoV6.jpg