MadModder

The Shop => Tools => Topic started by: j45on on April 09, 2011, 04:30:41 PM

Title: Tiny CNC router
Post by: j45on on April 09, 2011, 04:30:41 PM
I am building a tiny CNC router based on this http://makeyourbot.org/mantis9-1
But I am beefing it up a little with proper ball bearing slides with a view to remaking the frame from aluminium if I can get it all working correctly  :hammer:
This is what I have "thrown" together so far
(http://i602.photobucket.com/albums/tt102/ja2onx/minirouter.jpg)

I have now got to the point where I need electronics  :zap: I was originally going to use some salvaged printer stepper motors but I don't think they will be up to the job.
Does anybody see any problem with one of these ? http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=280655297567&ssPageName=STRK:MEWAX:IT#ht_6455wt_1141

I only want to engrave wood and maybe some aluminium with this either using a dremmel or a custom spindle and brushless motor
Title: Re: CNC router
Post by: Rob.Wilson on April 09, 2011, 04:48:18 PM
Hi Jason

sorry i cant answer your question  :doh: 

Looks a cool project  :dremel:   :thumbup: ,,,,,,,,,, what size is the work table ?

Rob
Title: Re: CNC router
Post by: j45on on April 09, 2011, 04:58:24 PM
I'm unsure  :scratch: I will measure it tomorrow I also don't know what the usable table surface area is yet
The whole thing is only 300mm x 300mm square though.
Title: Re: CNC router
Post by: Rob.Wilson on April 09, 2011, 05:31:09 PM
Jason

would this be any use to you on your build ?
 (http://www.nam-engineering.com/cm/albums/userpics/10002/normal_P1030206.jpg)
 (http://www.nam-engineering.com/cm/albums/userpics/10002/normal_P1030205.jpg)

280 x 220 x 25  ally ,,,,,,,,,needs a clean

Rob
Title: Re: CNC router
Post by: saw on April 09, 2011, 05:46:15 PM
This looks to be an very intressting project, I will follow this  :thumbup:
Title: Re: CNC router
Post by: raynerd on April 09, 2011, 05:56:33 PM
Jason, good luck with this. It is something I am massively interested in, infact I started making one a while back:
http://www.raynerd.co.uk/?p=532

However, it was a little bit too big AND the electronics were just working out far too expensive. I purchased a very cheap driver off ebay for £10 and it blew up with imo, no fault of my own I! I then purchased a cheap second hand motor and couldn`t get it to work. Then I went and purchased a motor and driver from ArcEuro and had no issue with them, they worked perfectly but they were for my milling maching x-axis stepper driver controller so for three more, I just couldn`t afford it!! I sold the lead screw and infact, I sold the table as far as I had got with it!!

I`m hoping I`m going to get some help with a build during summer so I`d be really interested to see if those drivers and motors do the business! I have seen them on ebay before and wondered!

Chris
Title: Re: CNC router
Post by: j45on on April 09, 2011, 06:09:48 PM
Jason

would this be any use to you on your build ?
Rob

Might be rob if I get it working  :zap:
I shall keep it in mind  :thumbup:

I went with this one in the end Chris as it also had a power supply http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260754805346&ssPageName=ADME:B:EOIBSA:GB:1123#ht_6225wt_1141
I will let you know if it is any good.
Title: Re: CNC router
Post by: Imagineering on April 09, 2011, 07:04:00 PM
Hi Jason,

Have a look at http://cnczone.com/
There you will find many answers to the many questions you will have on your quest for CNC.

Murray.
Title: Re: CNC router
Post by: Swarfing on April 10, 2011, 03:46:13 AM
Jason

I use a similar board for my router with the same size motors and it works fines. Setting up the board can be a bit of a pain but with the screw you are using i don't see a problem. My work area is 700 x500. Join this site as is very useful and a dam good bunch of blokes http://www.mycncuk.com.
Title: Re: CNC router
Post by: j45on on April 10, 2011, 06:46:55 AM
Cheers for the links guys  :thumbup: there is so much information to take in  :coffee:
Title: Re: Tiny CNC router
Post by: j45on on April 10, 2011, 01:05:39 PM
I had a bit of time this afternoon so I knocked up a new anti-backlash nut from some Delrin I was not happy with my previous effort.( on the right)
The new one (left) is longer and has three thin slots (very hard no see) in the end which are held shut with an o-ring.
(http://i602.photobucket.com/albums/tt102/ja2onx/back1.jpg)

This all runs nice and smoothly now with no noticeable backlash in the screw and nut  :ddb:
But I now need to find some thicker angle or another way to mount the nut as the current piece of angle flexes  :doh:

(http://i602.photobucket.com/albums/tt102/ja2onx/rou1.jpg)
 
Title: Re: Tiny CNC router
Post by: j45on on April 10, 2011, 03:28:14 PM
Managed a bit more shed time and finished up a clamp thingy  ::)
The lead screw is supported by two bearings at the front which are the same thickness as the wood and are a very tight fit with a flanged screw to prevent movement.
at the rear I have just one bearing.
(http://i602.photobucket.com/albums/tt102/ja2onx/bb2.jpg)

To stop the lead screw from moving I just have a spacer between the oldham coupling at the front which rides on the inner race.


(http://i602.photobucket.com/albums/tt102/ja2onx/bb.jpg)

And on the other side a have a pinch clamp thingy I knocked up which rides on the inner race, these are held tight against the bearings and then have their screws tightened preventing the lead screw from moving
Not as good as a thrust washer but seems to be ok time will tell.

(http://i602.photobucket.com/albums/tt102/ja2onx/bb3.jpg)
Title: Re: Tiny CNC router
Post by: j45on on April 13, 2011, 03:57:05 AM
Well my steppers and controller have arrived

(http://i602.photobucket.com/albums/tt102/ja2onx/5e9bc3fc.jpg)

And after a while last night I had all three running, as to if it is any good as mentioned in the "lost posts" time will tell.
Title: Re: Tiny CNC router
Post by: John Swift on April 13, 2011, 05:32:40 AM

Hi jason ,
 
I'm following your progress with great interest

 it looks like a good machine to try out our diy cnc skills ,

I hope your board has the problems fix that existed in the early versions of the board described in the cnczone posts

missing link from  lost post :- How I fixed my Chinese TB6560 controller (updated)

http://www.cnczone.com/forums/general_electronics_discussion/110986-how_i_fixed_my_chinese.html

  good luck

      John
Title: Re: Tiny CNC router
Post by: j45on on April 13, 2011, 07:26:48 AM
Thanks John I had not bookmarked the link,I have now  :thumbup:

I also thought this would be great to learn about cnc.
There would be no point converting my mill for example if I could never figure out how to use the software.
I was watching some Mach3 videos last night I would have been stuffed without them,very helpfull.
http://www.machsupport.com/videos/
Title: Re: Tiny CNC router
Post by: John Stevenson on April 13, 2011, 08:21:26 AM
Jason,
Shout up if you get stuck on programming or Mach, I have used it the odd time or so.

John S.
Title: Re: Tiny CNC router
Post by: j45on on April 13, 2011, 05:02:41 PM
Jason,
Shout up if you get stuck on programming or Mach, I have used it the odd time or so.

John S.
Many thanks John  :thumbup: hopefully I wont have to but with so much cnc info on the net it can all get a bit confusing

For the life of me I cant find out how to work out my steps per mm when using micro-stepping  :palm:
My motors are 200 step per revolution
My lead screws are 2mm per revolution
I have the stepper driver set to 1/8 micro steps (the motors seem a lot quieter set like that)
Title: Re: Tiny CNC router
Post by: John Stevenson on April 13, 2011, 05:09:06 PM
Steps per revolution x microsteps / pitch

so 200 x 8 =1600 / 2 = 800
Title: Re: Tiny CNC router
Post by: j45on on April 13, 2011, 05:15:23 PM
Steps per revolution x microsteps / pitch

so 200 x 8 =1600 / 2 = 800

Thank you John  :beer:
Title: Re: Tiny CNC router
Post by: j45on on April 16, 2011, 05:23:27 PM
Just a quick video of one axis working I'm still playing and tuning so it will probably go a bit quicker


hhmmmm video not imbedding  :scratch:

Title: Re: Tiny CNC router
Post by: John Swift on April 16, 2011, 07:40:43 PM

Hi Jason,

it will be a while before i'm ready but

i've had a look at the Mach3 videos  , lots of information to keep in mind thanks

your video looks like a good start

can't wait for the next one when its all running


one thing missing from your board is a charge pump circuit

just incase the computer stops working

http://www.machsupport.com/docs/ChargePumpSafety.pdf




while the  madmodders move has been taking place

I had another look at the cnczone thread and decided for problem boards

most of the mods could be made as a plug in adaptor / new breakout board

that plugs in the opto isolator and IC sockets


   John


Title: Re: Tiny CNC router
Post by: j45on on April 17, 2011, 02:50:45 PM
Cheers John
Knowing next to nothing about CNC or mach3 I dont know if my driver board is faulty or not yet  :scratch:
All I know so far is that all three motors move when I press some keys and the DRO'S match the distance traveled.
Until I get it finished I guess I wont know.

I did some googling on charge pumps and I'm still confused :doh:
Title: Re: Tiny CNC router
Post by: John Swift on April 17, 2011, 04:09:43 PM
Hi Jason ,

the charge pump circuit is a simple voltage doubler circuit thats used as a "missing pulse" detector

this is used to generate a E-stop signal if the computer stops working

mach 3 can be configured to send  12500 pulses a second to pin 1 ,say

this is ac coupled to the junction of the two bat85 diodes to ensure the circuit doesn't respond to a static logic level

the hidden gate capacitance is charged as long as the pulses arrive on time

the fet is now  on and via the relay and E-stop circuit power enabled for  the machine

if / when the pc stops working the pulses to the circuit is lost and the E-stop activated

the second circuit achives the same thing with a timer circuit as long as it is reset in time

hope this makes sence

    John
Title: Re: Tiny CNC router
Post by: j45on on April 17, 2011, 05:53:41 PM
That make sense  :thumbup:

I have noticed that the motors make a "misfire like noise" every so often is this missed steps ?
And the motors make a hell of a noise when stopped would this be the motors or the driver ?

I think rather than trying to mod this driver I would go for separate drivers and a break out board
For my tiny machine these would probably do http://www.skpang.co.uk/catalog/product_info.php?products_id=576 worth trying one at that price
and use one of these http://www.diycnc.co.uk/html/pcpps.html it has a built in charge pump
Title: Re: Tiny CNC router
Post by: John Swift on April 17, 2011, 07:27:27 PM

Hi Jason ,

at the moment I don't have a system to play with so you are a few steps on from me

but if you can move your table up and down several times under load and the real position

is the same as mach thinks it is , your probably not missing steps

the noise you hear from the motor is mainly because the supply to the motor winding is chopped (PWM) to limit the current

this in conjunction with motor resonances and the interaction of a switch mode power supply you will hear various noises


if you don't need all signals in and out isolating the breakout board looks ok

the stepper drivers are a bit small for you motors I expect you will need to run them at the limit of 2A per phase

and still under run your motors

 John
Title: Re: Tiny CNC router
Post by: Rob.Wilson on April 18, 2011, 02:54:18 AM
That make sense  :thumbup:

I have noticed that the motors make a "misfire like noise" every so often is this missed steps ?
And the motors make a hell of a noise when stopped would this be the motors or the driver ?



Hi Jason ,,,,,, i had the same thing when setting up my  small cnc mill , it did the same  if i have the motor speed/ accel rate  set to high  ,,, try slowing things down a bit .

Rob
Title: Re: Tiny CNC router
Post by: j45on on April 23, 2011, 06:39:22 AM
Went out to buy some microswitches/limit switches this morning seemed like a good excuse to take my motorbike out
Until I stalled it trying to do a U turn in the shop car park and fell over   :palm:
I will fit them when I have calmed down a bit  :med:
Those switches will now cost me more than I have spent on the entire project now  :(
Title: Re: Tiny CNC router
Post by: kwackers on April 23, 2011, 08:45:12 AM
I feel your pain.

I dropped a brand new (200 miles) ZZR1100 turning left because I stalled it. There was a scrape on the fairing where it had caught the kerb, not much but on a new bike it just stood out (although my missus claimed she couldn't see it!).
In the end I bought a new panel, cost me £200.

Mind you I high-sided my ZX12 at around 10mph with just a bit too much throttle on cold tyres pulling out the top of the road, that cost me the best part of a grand to fix.
I was impressed how far up it managed to throw me, gave me an insight into how trebuchet's work...
Title: Re: Tiny CNC router
Post by: j45on on April 23, 2011, 03:52:41 PM
I think I managed to burn a road runner into the bed today
(http://i602.photobucket.com/albums/tt102/ja2onx/rr.jpg)
I have a laser pointer in place of the z axis at the moment
Then I broke the Y axis lead screw nut bracket  :bang: I had been having trouble with the home switch triggering an e-stop so I turned it off  :doh:
Title: Re: Tiny CNC router
Post by: John Stevenson on April 23, 2011, 06:10:08 PM
I had been having trouble with the home switch triggering an e-stop so I turned it off  :doh:

Triggering the E-Stop can be a few things, E-Stop, wiring, noise in the circuitry and same for limit switches.

Best bet is to get it up and running , then fit limit switches, remember many machines don't even have them.

In Mach, go to Config > General config and it the top right hand corner change the debounce interval setting from the default 20 or 40 to 100 and then try it.
You can go as high as about 5000 if you are struggling, move in increments of 100 at a time.

John S
Title: Re: Tiny CNC router
Post by: j45on on April 23, 2011, 07:05:00 PM
Cheers John  :beer:
I will have another crack at it tomorow once I have repaired it  :hammer:
I have done a ton of reading tonight and have lots of bookmarks,but it is the simple stuff that stumps me like which way should my axis move  :scratch: and where should the home position be ?
Title: Re: Tiny CNC router
Post by: John Stevenson on April 23, 2011, 07:42:09 PM
For movement it's ALWAYS the tool that moves.
Z is easy +Z is up, -Z is down.

For X when you press the right arrow the bed moves to the left MAKING THE TOOL MOVE THE SAME WAY AS THE ARROW
For Y the down arrow makes the bed go towards the column MAKING THE TOOL MOVE THE SAME WAY AS THE ARROW

Place your hand on the top right of the bed, covering the end and the back. both these directions are X+ and Y+ respectively.
Remember right hand and both are plus moves.

Home when you come to set it is arbitrary. The sensible position for Z is at the top.
Y can be towards the column or towards the operator, X can be right or left and these two are purely personal.
Title: Re: Tiny CNC router
Post by: j45on on April 24, 2011, 12:15:40 PM
 :bow: big thanks John  :bow:
I feel like i am getting somewhere now,I was close to giving up the other day
This is all I have managed so far as lazy cam would only let me cut quarter of a gear


 :ddb: :ddb: :ddb:
Title: Re: Tiny CNC router
Post by: John Stevenson on April 24, 2011, 12:25:48 PM
Why only 1/4 of a gear?
Title: Re: Tiny CNC router
Post by: j45on on April 24, 2011, 12:32:36 PM
it's the demo i guess I put the whole gear dxf into lazy cam and it only posted 49 lines
Title: Re: Tiny CNC router
Post by: Imagineering on April 24, 2011, 10:03:30 PM
Hi Jason,

What are you useing as a cutter. You mention a "Laser Pointer", but this one seems to cut????

Murray.
Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 03:16:03 AM
Sorry Murray that was a bit misleading when I said "cut quarter of a gear"
It will only lightly scorch , I made it some time ago now following this tutorial
http://www.photonlexicon.com/forums/showthread.php/5065-Tutorial-My-Pocket-Pal-Blu-ray-Laser!
I estimate mine to be about 100mw
This guy has some info on using low power laser diodes for CNC
http://www.cooperman.talktalk.net/files/18.htm

I am currently/slowly collecting parts to build one of these http://www.buildlog.net/blog/2011/02/buildlog-net-2-x-laser/
That should cut wood and acrylic up to 1/4" and maybe more  :)
Title: Re: Tiny CNC router
Post by: John Stevenson on April 25, 2011, 05:29:57 AM
Jason,
So how will this compare against buying say the LS3020 from HPC laser ? Also what power laser is required to mark steel, like a trade mark?

I know you can buy this spray on gear but it's very expensive, the tape is even worse at £145 a roll.

John S.
Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 06:15:11 AM
Hi John
The LS3020 has a work area of 12' x 8" and 35W
The buildlog 2.X one has 12" x 20" work area and 40w

I am hoping to build it for around the same price (ish) but you know how budgets go  :palm:
Then here is the fun of the build itself  :) and I can spread the build and costs as funds allow
People seem to spend a lot of time modifying these chinese lasers so why not build a good one from scratch  :hammer:
I have also read that the control methods and software for the chinese lasers is a bit crap and people generally convert them to mach3 or use one of these dedicated laser controllers

http://www.lightobject.com/Commerical-DSP-CO2-Laser-Engraving-Cutter-Controller-Support-CorelDraw-AutoCad-P321.aspx?afid=1

http://www.fullspectrumengineering.com/RetinaEngrave.html

I have ordered about 300 quids worth of parts now so there is no turning back,on the down side there is very little for me to make only the air assist nozzle to machine and cut the machine skins ( unless I can get them laser cut locally cheep)

I think you need a shed load of power to mark steel probably hundreds of watts the cermark stuff just melts to the surface I think  :scratch:

Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 09:49:29 AM


I need to stop playing and go and build a Z axis  :hammer:
Title: Re: Tiny CNC router
Post by: John Stevenson on April 25, 2011, 10:16:54 AM
Yup, I think so too   :headbang:

I have just finished this.

(http://www.stevenson-engineers.co.uk/files/4axis_box.jpg)


And before anyone asks the fan is at the far end blowing into the power supply

John S.
Title: Re: Tiny CNC router
Post by: kwackers on April 25, 2011, 10:25:06 AM
What have you done...

I've been admiring the small laser cutters for a while now - I don't need one, but they're just so cool.
Now you've pointed to a site that has a PD version and sells parts!  :bang:

Out of interest, have you bought any of the parts or kits listed? I wonder if he exports to the U.K...
Now I'm here - any more pointers? I guess I've so many projects one more won't hurt...
Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 10:35:53 AM
Hi Kwackers
He will post to the UK
I have ordered from him
http://www.buildlog.net/cnc_laser/store/2x_kits_and_parts.php
1x Plastic parts
1x Hardware kit
1x Mechatronics kit
1x Linear bearing system
my bits are on route via USPS he quoted 8 to 10 days

The only bit I will have trouble with is the misumi extrusions as they will only sell to vat registered companies  in the uk  :scratch:
I have phoned them and sent a begging email but no luck so far.
Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 10:46:08 AM
Yup, I think so too   :headbang:

I have just finished this.
And before anyone asks the fan is at the far end blowing into the power supply

John S.

Very profesional John  :bow: (makes mine look like a birds nest that fell out of a tree and got run over)
What is it going to control ?
Title: Re: Tiny CNC router
Post by: DMIOM on April 25, 2011, 11:56:42 AM
Quote
.......Now I'm here - any more pointers? I guess I've so many projects one more won't hurt...

Now, would that be a laser pointer ????    ::)  

(p.s to Eric - with all this laser talk, maybe we need another smiley with dark glasses!   :coffee: )



Quote
The only bit I will have trouble with is the misumi extrusions as they will only sell to vat registered companies  in the uk
PM sent

Dave
Title: Re: Tiny CNC router
Post by: kwackers on April 25, 2011, 12:02:44 PM

The only bit I will have trouble with is the misumi extrusions as they will only sell to vat registered companies  in the uk  :scratch:
I have phoned them and sent a begging email but no luck so far.

Funnily enough - just the end of last week I registered for VAT...

I registered for flat rate so might be a few weeks before the number comes through though. Could be that we put in an order x2....
Title: Re: Tiny CNC router
Post by: j45on on April 25, 2011, 12:10:46 PM
Funnily enough - just the end of last week I registered for VAT...
I registered for flat rate so might be a few weeks before the number comes through though. Could be that we put in an order x2....

That would be handy  :thumbup:
Title: Re: Tiny CNC router
Post by: j45on on April 26, 2011, 12:49:59 PM
Im have stripped it down to a pile of parts now  :(
So I can build it better  :)
I  am confident now that the electronics work and I am getting the hang of mach3  :ddb:
I have ordered some 500mm hardened shaft to replace the 300mm to make it a little larger it  already had 500mm lead screws
and I'm on the hunt for some High quality ply wood the b&q stuff it was made from was cr*p
Title: Re: Tiny CNC router
Post by: HS93 on April 26, 2011, 02:30:27 PM
MDF is more stable and you can get 3/4" and even 1" thick it is very heavey because it is dense and you need to wear a mask but far better than ply if you look on most of the sites that people build these types of machine on they use MDF  .

Peter
Title: Re: Tiny CNC router
Post by: John Stevenson on April 26, 2011, 02:41:33 PM
You can also get HDF.

MDF is Medium Density Fibreboard
HDF is High Density Fibreboard.

Try asking at the local kitchen fitting place, they often have offcuts.

John S.
Title: Re: Tiny CNC router
Post by: j45on on April 26, 2011, 03:04:04 PM
I think it will end up being MDF depends what I can get locally tomorrow
This is what i wanted to use

(http://i602.photobucket.com/albums/tt102/ja2onx/Screenshot2011-04-26at195644.jpg)

15mm thick with 11 layers we had some at work for transit flatbeds very strong
this is all I have left after making shelfs and a paper towel holder

(http://i602.photobucket.com/albums/tt102/ja2onx/Screenshot2010-08-14at202212.png)

Isn't MDF a bit of a pain to screw into ?
Title: Re: Tiny CNC router
Post by: dsquire on April 26, 2011, 03:22:35 PM
j45on

It can be a problem putting screws into if not done properly. You should always predrill for screws before putting them in. Also, you should stay further away from the edge than in plywood. It is best not to put screws into the edges as it tends to split, especially if not predrilled. When using screws the worst thing you can do is to over tighten them and strip the threads out. Sometimes it is wise to use threaded inserts instead of wood screws especially if it must be adjusted or taken apart.  :D

Cheers  :beer:

Don

Title: Re: Tiny CNC router
Post by: HS93 on April 26, 2011, 04:02:09 PM
screwfix do MDF screws

Peter
Title: Re: Tiny CNC router
Post by: raynerd on April 26, 2011, 04:09:03 PM
Amazing work so far, really impressed. Are you still happy with the motors and drivers you purchased on ebay??

I recently used MDF screws and they were excellent - much better then standard screws and I won`t be screwing into MDF again without using them.

Chris
Title: Re: Tiny CNC router
Post by: j45on on April 26, 2011, 05:53:46 PM
Chris I am happy with the motors and controller for this machine but I have to keep the motor speed down or they make random thumps  missed steps ?
I did see a video on how to confirm missed steps in mach3 but I cant find it now  :palm:
For a larger machine needing more speed and power it may not be a good choice I think you might run into the problems mentioned previously but I'm no expert  :scratch:
The motors are also very noisy when idle not quiet like the stepper on my rotary table
Here is a video of the noise

&list=UL

Can any one explain in simple terms what "decay mode settings" are for  :scratch:
I am running 75% current and 1/8 microstep if that helps

(http://i602.photobucket.com/albums/tt102/ja2onx/dip.jpg)
Title: Re: Tiny CNC router
Post by: John Swift on April 27, 2011, 04:57:31 AM

Hi Jason ,

its good to see your making progress

I've found a tutorial at stepperworld tha may help you understand the current decay setting

I would of expected 25% or 50% to be a good compromise ??

http://www.stepperworld.com/Tutorials/pgMicrostepping.htm

reference made to Allegro  in tutorial ,

   A3979 data   http://www.allegromicro.com/en/Products/Part_Numbers/3979/3979.pdf
   

 John
Title: Re: Tiny CNC router
Post by: j45on on April 27, 2011, 02:23:04 PM
Cheers John  :thumbup:
I will have a read of that once I have washed the mdf dust out of nearly every orifice I have  :lol:

I failed to find any good ply today so 18mm MDF it is (this thing is not looking so tiny anymore  :palm: )

(http://i602.photobucket.com/albums/tt102/ja2onx/cncrouter2.jpg)

I am planning to cut grooves into the front,back and base pieces tomorrow( as shown bottom right in my plan)
so that with a bit of luck I can mainly glue it together and use less screws and prevent splitting, well thats the plan anyway  :hammer:

(http://i602.photobucket.com/albums/tt102/ja2onx/cncrouter.jpg)


Does anybody think this should belong in the project logs section ?
Title: Re: Tiny CNC router
Post by: John Stevenson on April 27, 2011, 03:04:45 PM
It's not a log, it's MDF................ :wave:

John S.
Title: Re: Tiny CNC router
Post by: spuddevans on April 27, 2011, 03:19:57 PM
It's not a log, it's MDF................ :wave:

John S.

But isnt MDF just finely shredded log?  :scratch:  :D


Tim
Title: Re: Tiny CNC router
Post by: j45on on April 27, 2011, 04:35:17 PM
For those that asked about chinese laser cutters
I found the web pages where people documented their experiences with chinese laser cutters

http://www.imajeenyus.com/workshop/20090506_laser_cutter/index.shtml

http://www.andyslater.com/laser-cutting/

http://www.stephenhobley.com/blog/2011/04/11/buying-a-laser-cutter-from-china-part-one/
Title: Re: Tiny CNC router
Post by: Bluechip on April 27, 2011, 04:50:57 PM
Hi Jason

Just had a very quick look at the links ... would this thing cut metal? ie something like .010" - .012" brass sheet?

Reason I ask is connected with something a mate and I were discussing last night, photo etched brass stuff. Like model railway wagons etc.



Dave BC
Title: Re: Tiny CNC router
Post by: j45on on April 27, 2011, 05:03:31 PM
This guy has built a laser that cuts metal http://nilno.com/cgi-bin/index.cgi
But it will not cut brass   :(

quote from his FAQ page

"Can I cut brass?
No. I cant either. The industry would love to cut brass and they aint figured it out either. I gather it's a problem due to the heat transmission of brass and copper. It spreads out its heat over the area of the cut too effectively. If you cant concentrate the heat on a particular area, the metal doesn't get obliterated. Steel is a lovely and cooperative metal."
Title: Re: Tiny CNC router
Post by: Bluechip on April 27, 2011, 05:12:37 PM
Thanks Jason

It was just a thought  ... and will forever remain so it seems ..



Dave BC

Title: Re: Tiny CNC router
Post by: John Stevenson on April 27, 2011, 05:48:14 PM
Industry can cut brass with a laser, I have a stack of 3mm thick disks here that have been laser cut.
just how much power was needed I don't know as the laser is quite a big one, about 3.5 to 4 Kw but the point is it can be done.
Plasma will cut brass with no problems, even those cheap Cut40 machines.

Polly models are cutting the brass cab parts out for the poly loco's with a Pacer router.

John S.
Title: Re: Tiny CNC router
Post by: j45on on April 27, 2011, 05:55:27 PM
What we need is a DIY water jet  :dremel:

My apologies dave a bit of googling proves that brass can be laser cut  :doh:
Title: Re: Tiny CNC router
Post by: j45on on April 28, 2011, 12:18:37 PM
I finished routing the base and sides today and it all fits together lovely  :ddb:

(http://i602.photobucket.com/albums/tt102/ja2onx/c6da99ee.jpg)

My longer rails also turned up  :ddb:

I'm thinking about turning up some large bed bolts to hold it together rather than glue and screws
or I maybe just buy some  ::)

EDIT at £4.22 for a bag of 50 I dont think I will be making any
(http://i602.photobucket.com/albums/tt102/ja2onx/600907_l.jpg)
Title: Re: Tiny CNC router
Post by: HS93 on April 28, 2011, 05:41:06 PM
Are you going to Glue and screw it together? if so what are the bed /cabnet bolts for ?

Peter
Title: Re: Tiny CNC router
Post by: j45on on April 29, 2011, 06:41:18 AM
Are you going to Glue and screw it together? if so what are the bed /cabnet bolts for ?

Peter

I was going to screw and glue but I may need to disassemble at some point so I'm going to use the bed bolts/cross dowels  http://www.screwfix.com/p/cross-dowel-m6-x-20mm-pack-of-50/22009
and these wide head bolts http://www.screwfix.com/p/joint-connector-bolts-m6-x-45-bzp-pack-of-50/64094
Title: Re: Tiny CNC router
Post by: HS93 on April 29, 2011, 08:38:45 AM
I would put some screws in as well  i get them from screw fix a big box 500  cheap they will stop any slip that you could get with the bed bolts

http://www.screwfix.com/p/mdf-tite-screws-3-9-x-40mm-pack-of-200/40376

peter
Title: Re: Tiny CNC router
Post by: j45on on April 29, 2011, 03:21:29 PM
I'm hoping I wont need screws Peter

But I have some space left between the bolts incase I need to

Still have to bolt the base to the walls that can wait until tomorrow now

(http://i602.photobucket.com/albums/tt102/ja2onx/36e5b9de.jpg)

(http://i602.photobucket.com/albums/tt102/ja2onx/9475bb4b.jpg)
Title: Re: Tiny CNC router
Post by: Bluechip on April 29, 2011, 04:02:11 PM
What we need is a DIY water jet  :dremel:

My apologies dave a bit of googling proves that brass can be laser cut  :doh:

Hi Jason

Only just spotted this

No problem. It was only part of a fairly casual conversation. My mate Norm. does strange things with Railway Dioramas etc. He makes some rolling stock etc. from these (wr) etched bits of brass but no-one makes the obscure stuff he wants. ( Why doesn't that surprise me ).

As he knows I have occasionally etched PCB's, he asked if the same stuff would etch brass. 'Dunno, it does copper OK'.

I then said if even it will (?) it would take forever to do .012" brass, 'cos the PCB copper is nowhere near that thick AFAIK.

Hence to end of conversation, in which I had virtually no interest, I suggested CNC laser.

At which point I confessed to knowing somewhat less than zero about Laser cutting, CNC or otherwise.

Left it with him, then just asked as I noticed your project, which I'm enjoying quite a bit.  :thumbup:

Onward and Upward ..

Dave BC







 






Title: Re: Tiny CNC router
Post by: John Swift on April 29, 2011, 04:29:59 PM

 Hi Jason ,

it's looking good ,now I know what to build as a first machine  :D

are you fitting your  laser to this one or a router?

can't wait for the video

I like the way the MDF parts fasten together  , all the parts being positively located

I must remember the threaded metal dowels for my projects  

 John

Title: Re: Tiny CNC router
Post by: John Stevenson on April 29, 2011, 04:42:38 PM
Dave, just read thru an article that was in MEW about metal etching brass and they reckon 75 minutes to do a sheet of 10 thou brass, good article by a bloke called John Purvis, far better than the workshop practice no 36 Photo Etching.

John S.
Title: Re: Tiny CNC router
Post by: Bluechip on April 29, 2011, 05:03:17 PM
John S.

Cheers, I'll point him in that direction  :thumbup:

No great desire to get involved really. Too many wheels on railway stuff.

Two is the ideal number. Any more is sheer exhibitionism, a gross waste of precious resource and should be expressly forbidden.

( might make an exception for Brewery Trucks)  :beer:

Dave BC

EDIT .. Owd on a bit .. current issue or what ???
Title: Re: Tiny CNC router
Post by: John Swift on April 29, 2011, 05:34:14 PM

Hi Dave ,

while we are waiting for John to tell us what issue of MEW we need to read

have a look at this :--

http://steampunkworkshop.com/electroetch.shtml

 John
Title: Re: Tiny CNC router
Post by: j45on on April 29, 2011, 05:52:11 PM
are you fitting your  laser to this one or a router?

This will get my dremel  :dremel: to start with and maybe a better spindle later on
I suppose i could also attach the laser pointer as well but I have a proper laser cutter on my next to build list , this one http://www.buildlog.net/blog/2011/02/buildlog-net-2-x-laser/
Title: Re: Tiny CNC router
Post by: John Stevenson on April 29, 2011, 05:55:11 PM
MEW 108 and 109
Title: Re: Tiny CNC router
Post by: Bluechip on April 29, 2011, 06:04:27 PM
Thanks John & John

We are  :offtopic: a lot   :thumbup:

Dave BC
Title: Re: Tiny CNC router
Post by: j45on on May 01, 2011, 03:30:18 PM
It's getting there slowly  :poke:
You might notice the design feature which is the back panel  :palm: ( I damaged the first one and then cut a new one to short  :doh:
The bed will have another ( sacrificial ) layer of MDF on top

(http://i602.photobucket.com/albums/tt102/ja2onx/mk2-2.jpg)

(http://i602.photobucket.com/albums/tt102/ja2onx/mk2-1.jpg)

(http://i602.photobucket.com/albums/tt102/ja2onx/mk2-3.jpg)

I'm waiting for some Z axis linear slides I need two more
I need to make some more anti backlash nuts
Fit limit switches
Bolt frame to base
Make some bearing retainers ( the self tapping screw I used on the last one is not good enough for this )
Find some MDF sealer ( I don't want to paint it just protect it )
Title: Re: Tiny CNC router
Post by: j45on on May 07, 2011, 03:47:27 PM
A few more piccys it's nearly finished (maybe tomorrow  :ddb:)

(http://i602.photobucket.com/albums/tt102/ja2onx/mill-2.jpg)

For the lead screw bearings I went with three in the end as they are the same thickness as the wood

(http://i602.photobucket.com/albums/tt102/ja2onx/mill4.jpg) :drool:

these are clamped tight with tow bar washers on either side using 3mm pan head screws

(http://i602.photobucket.com/albums/tt102/ja2onx/mill3.jpg)


(http://i602.photobucket.com/albums/tt102/ja2onx/mill2-1.jpg)
Title: Re: Tiny CNC router
Post by: John Swift on May 07, 2011, 04:21:12 PM

Hi Jason ,

its looking good
by this time next week , you will be having fun using it

   John
Title: Re: Tiny CNC router
Post by: John Stevenson on May 07, 2011, 04:23:56 PM
Jason,
I like the idea of the shaped sides, easy to cover in and fit an extractor, Must do something with my Techno Isel, it spends a lot of time routing out tufnol brush rings for electric motors and the damn dust goes everywhere.

Full marks for neatness, I like it.

John S.
Title: Re: Tiny CNC router
Post by: dickda1 on May 07, 2011, 08:27:21 PM
I really like your decision to use MDF.  It gives you much more flexibility in testing the design than if it was done in aluminum.  The delrin nuts are nice too. I have some ball screws and nuts from a lab I closed down.  They are so expensive that I have been staring at them on a shelf for years looking for just the right project - so nothing gets done.  You really have shown a cheap way to get started.  Thanks. :thumbup:
-Dick
Title: Re: Tiny CNC router
Post by: j45on on May 10, 2011, 02:25:47 PM
If anybody is considering building a mini/desk top router you may be interested in this linear bearings system

(http://i602.photobucket.com/albums/tt102/ja2onx/makerslide_o1.jpg)

http://www.makerslide.com/

And the kickstarter project http://www.kickstarter.com/projects/93832939/makerslide-open-source-linear-bearing-system

If bart can secure funding to produce the linear bearing extrusion his first open source project with it will be for smallish fully enclosed CNC router

Quote from his website
"My first new open source project with the MakeSlide will be a smallish, fully enclosed CNC router. It will have a very quiet spindle and an integral dust collection system. The dust collection will be a shop vacuum. Some are very, very quiet like the Festool vac. The spindle will be a small (0.8kW-ish) 3 phase air or water cooled spindle. The enclosure may have some noise dampening panels to it. The only noise will come from the material being cut. If you cut foam or are milling a PCB, you could have a conversation next to it.

I want it to have killer curb appeal too, because I love a sweet looking design. I think the 2.x was a big step in that direction over the original laser. I want this to take an equal step that way."

If this shameless plug is against forum rules please let me know and I shall remove it
Title: Re: Tiny CNC router
Post by: dsquire on May 10, 2011, 03:23:40 PM
Jason

I looked at that link as well. If he can get that project off the ground with the initial run of extruded aluminum with the V rail built in then he will have a winner. It will certainly help to bring the costs down. I will be watching it to see what happens.

Cheers  :beer:

Don

Title: Re: Tiny CNC router
Post by: j45on on May 14, 2011, 04:55:19 PM
I have finally finished the router  :ddb: ( well nearly, I still have to add Z axis limit and home switches  :hammer: )
Unfortunately I did not record the running video ( I thought I had  :palm: ) so you will have to make do with a picture instead

(http://i602.photobucket.com/albums/tt102/ja2onx/16f76c30.jpg)

I will try something a bit more adventurous tomorrow but I only have an engraving bit at the moment http://www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Engraving-Cutters

PS: the Makerslide I posted previously is now 181% funded  :ddb:
Title: Re: Tiny CNC router
Post by: John Swift on May 14, 2011, 05:34:23 PM

Hi Jason ,

its good to see you are making progress  :clap:

what diameter is the gear outline you have cut , It looks like you will be making clocks next

unless you are planning a third machine with the makerslide ,when its available here in the UK

a good result with the makerslide  funding


   John




Title: Re: Tiny CNC router
Post by: j45on on May 14, 2011, 05:41:59 PM
Hi John
I think it was about 50mm and half a mm deep, I cut it with a 1/8" one of these it's all I have at the moment
(http://i602.photobucket.com/albums/tt102/ja2onx/Screenshot2011-05-14at223510.jpg)

Title: Re: Tiny CNC router
Post by: John Swift on May 14, 2011, 06:33:40 PM

Hi Jason ,


the cutter looks simple enough to make your self
if you have the grind stones for carbide ( green grit stones ?)

although it will only worth it ,if the carbide blank  is cheap enough

I expect they should be OK cutting the copper on PCB's

 John

Title: Re: Tiny CNC router
Post by: Bogstandard on May 14, 2011, 07:45:34 PM
John,

Those cutters are not a thing you could grind up by hand, just like the side flutes on a milling cutter. They are fed not only forwards, but sideways into the wheel at the same time, it is that which gives the cutter it's clearance at the back.
They really need to be done on a T&C grinder.


Jason,

I had a look at those ali extrusions and guide wheels. I used to work on a similar set up on Universal DIP inserting machines where they had a triangular shaped profile running in a bearing with a triangular cutout in them.

I can tell you now, they are not very easy to set up for correct clearance for smooth running. We would spend at least a couple of hours trying to align just four of the bearings, and they had a very fine cam system in the middle of the bearings to do the job. You only had to breathe on them and they would either tighten up or go slack.
Definitely not as simple as the designer of that system thinks, and unless the triangular edge is hard anodised, it will wear away and brinell in no time. Been there and got the t-shirt.


John
Title: Re: Tiny CNC router
Post by: HS93 on May 14, 2011, 08:08:52 PM
How about the bottom wheels fixed and the top sprung pushing it down on to the bottom runners, it is not the type of machine that a lot of force will be used on the cutter's I would have thought and a Lazer would not have any, so once the bottom wheels are set the top would self ajust .

just a thought

    Peter
Title: Re: Tiny CNC router
Post by: John Swift on May 15, 2011, 07:15:06 AM


Hi John,

Yes john you are right ,I didn't mean free hand ,but with just one cutting edge it would be easier than attempting a multi fluted cutter

the process I had in mind is to first grind an eccentric cone ,with the tool held in a live spindle

then using a fixed jig(s) to remove half the cone ,then grind the clearance at the cutting edge

 John

Title: Re: Tiny CNC router
Post by: j45on on May 15, 2011, 06:37:06 PM
Well the first thing I did today was break the tip off of the cutter  :doh:
I shall have to wait for the postman to bring me some more now.
Title: Re: Tiny CNC router
Post by: j45on on May 19, 2011, 06:25:59 PM
Finally I have made something other than saw dust with this router   :D
It's a small puzzle made from 3mm ply wood about 2" round

(http://i602.photobucket.com/albums/tt102/ja2onx/puz1.jpg)

(http://i602.photobucket.com/albums/tt102/ja2onx/puz2.jpg)

Terrible pics but I only had my phone to hand
Title: Re: Tiny CNC router
Post by: John Swift on May 19, 2011, 06:37:42 PM


Hi Jason ,

thats great ,  :D

no doubt you can use it  to make parts for the next one , if your not to busy making other things   

    :beer: :beer:

   John
Title: Re: Tiny CNC router
Post by: cfellows on May 20, 2011, 06:55:34 PM
That's a cool machine you've made there.  I keep thinking I would like to get into CNC, but then again, not sure what I'd use it for and I hate to spend the money.

Chuck
Title: Re: Tiny CNC router
Post by: j45on on May 21, 2011, 09:44:37 AM
Chuck I'm only doing it for fun I have no real use for it   :D
But I'm sure I will find uses like isolation routing PCB's, cutting openings in project boxes
Making wooden puzzle boxes.
My sister makes silver jewelry and is already asking me if I can engrave items for her

This is today's experiment  :ddb:
(http://i602.photobucket.com/albums/tt102/ja2onx/45c19482.jpg)
Title: Re: Tiny CNC router
Post by: saw on May 21, 2011, 10:24:31 AM
Nice I am shure that you will find some work for your router  :thumbup:
Title: Re: Tiny CNC router
Post by: j45on on May 21, 2011, 02:09:24 PM
Attempted to make a keyring,cut these from 4mm PVC
And tried to cut a window from a CD jewel case  :dremel: but it melted my dremel is to fast  :doh:

(http://i602.photobucket.com/albums/tt102/ja2onx/keyring.jpg)
Title: Re: Tiny CNC router
Post by: No1_sonuk on May 21, 2011, 05:44:31 PM
I have a vibrating fretsaw like that.  You push the plastic into the blade, and when it comes out the other side, it's welded back together!
Title: Re: Tiny CNC router
Post by: HS93 on May 21, 2011, 06:55:37 PM
drip water on the blade and it wont melt back together, I cut a lot of platicard.

Peter
Title: Re: Tiny CNC router
Post by: j45on on May 29, 2011, 03:44:57 PM
I have made a little round box which my sister has pinched  :wack:
And a madmodder drinks coaster  :lol: just playing around really  ::)

(http://i602.photobucket.com/albums/tt102/ja2onx/mm.jpg)
Title: Re: Tiny CNC router
Post by: spuddevans on May 29, 2011, 04:20:26 PM
Nice coaster, give it a lick of clear-coat and slap (gently) a pint on it :thumbup: :thumbup:



Tim
Title: Re: Tiny CNC router
Post by: j45on on May 30, 2011, 01:57:54 PM
Today I decided to re house this case less memory stick
It cost me a small fortune when new so I cant bring myself to throw it away even though it only has 64MB  :lol:

Started by carefully measuring and routing out a side out of a bit of walnut

(http://i602.photobucket.com/albums/tt102/ja2onx/1-2.jpg)

Followed by another side,notice the extra pocket I had to add manually  :dremel:
 
(http://i602.photobucket.com/albums/tt102/ja2onx/4-1.jpg)

Only now I have finished do I notice I should have made it a bit longer to cover the usb better  :palm:

(http://i602.photobucket.com/albums/tt102/ja2onx/3-2.jpg)

All done well nearly I still have to put my name on it

This took nearly 2 hours with a 1mm end mill  :bang:

(http://i602.photobucket.com/albums/tt102/ja2onx/6-1.jpg)

The jig to hold it ( this reminds me of the movie 2001  ::) )

(http://i602.photobucket.com/albums/tt102/ja2onx/5-1.jpg)

Work in progress

(http://i602.photobucket.com/albums/tt102/ja2onx/8.jpg)

Now it's done  :ddb:

(http://i602.photobucket.com/albums/tt102/ja2onx/7.jpg)

Title: Re: Tiny CNC router
Post by: saw on May 31, 2011, 09:57:16 AM
nice  :bugeye: