# CNC routing



## RussianRouter (20 Jun 2010)

Ok,this was f*ing awsome and I'm hooked,Fecn if your still around? then it takes brains to work something like this out and the outcome of this has clearley shown that it works,a bit crude but never the less it can be tweaked here and there.

Just wish I was around at the time this came up.  

https://www.ukworkshop.co.uk/forums/my-n ... 19561.html

I'm hooked and I gotta build one now  however this won't be as big as the prototype of Fecn's(nospace to swing a cat)

After I've made myrouter table I'll set about planning the motion bed,I reckon half the size or smaller should do it?

Got the perfect router for the engraver and if its still available it'll be cheap to buy,mind you its 4 or 5 years ago when I bought it? and never used it a lot when I did.

I'll post a pic when the batteries have charged up.


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## RussianRouter (20 Jun 2010)

Its £348 if Igo to MCP

http://www.motioncontrolproducts.co.uk/ ... ducts_id=8

And if I go direct to HongKong its £283,thats a helluva saving.


http://cgi.ebay.co.uk/Cnc-Mill-3-axis-K ... 5ad9f200a1

Anyone know how much import duty is?I have had items before from HongKong and the States but these items were below£50 and I think import duty is only applied when it reach's £100 or more?


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## CNC Paul (20 Jun 2010)

George, 

The import duty is 17.5% vat plus a levy of 3-5%, the bit you will suffer is to pay the shippers to collect it. I had to pay £21 duty and vat on an import, DHL charged me £12 to collect the £21. 

You are trying to save £63, by the time you add shipping, duty, import charges and credit card charges you will have even less of a saving. If you have a problem and you need to return it you will incure futher costs. 

I had a machine part that broke, the US company replaced it under warranty they told me not to bother sending the old one back, because I had not returned it Customs and Excise made me pay the vat and duty again and the DHL charge. If I had returned it I would not need to pay again.


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## RussianRouter (20 Jun 2010)

Hi Paul 

So in effect won't really workout cheaper from HongKong?

I'm browsing the HMCustoms and Excise site and its a bloody headache trying to calculate the duty.


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## RussianRouter (20 Jun 2010)

> I had a machine part that broke



I was reading something about faulty products and it says something about you should not pay vat duty for defective items?


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## CNC Paul (20 Jun 2010)

George,

You need to have proof that you have returned the goods as faulty.


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## RussianRouter (20 Jun 2010)

I've worked it out cheaper from MCP.

Its £20 for the breakout board(considerably dear for just a board with no components and only a plug and board)),don't need this as I can wire the parallel port up myself.

£57 for the power supply I only need one power supply,as I can find a power supply cheaper to drive the motors.

So it will cost £281 with the P&P


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## CNC Paul (20 Jun 2010)

George, 

You can get a breakout board for £12 from here. It is easier to wire the parallel port / LPT port with one.

http://www.routoutcnc.com/index.html


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## RussianRouter (20 Jun 2010)

Thanks Paul.

Ok got it down to £268 with P&P and I'm hoping that the VAT is inclusive? because I can't see anywhere on the site that refers to VAT inc.


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## RussianRouter (20 Jun 2010)

Anyone know where to get steel rods cheapish? about 8mm to 10mm diameter and 450mm long

The links I posted in here a week or so ago? the rods are too dear.


I'm thinking of using wardrobe chrome rails at £7 pkt of 5 but I really need 6.

Rails would be better as I would'nt have the horizontal carriage axis going from left to right and knocking your head off if not too careful ie the carriage would be positioned in the middle stationary and the vertical axis would travel back and forth on the rails.

I sure could have given FecN some of my engineering background knowledge on this.


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## CNC Paul (20 Jun 2010)

George,

Have a look at 3d Warehouse under CNC there are lots of homebuilt CNC's which you can look at with Sketchup.


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## RussianRouter (20 Jun 2010)

Can't find it,Paul ie...find the warhouse but not CNC

Hah,got it,thanks Paul


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## CNC Paul (20 Jun 2010)

http://sketchup.google.com/3dwarehouse/ ... tnG=Search


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## WoodAddict (20 Jun 2010)

I've planning one of these for a while now. have a look here mycncuk.com


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## RussianRouter (20 Jun 2010)

Bought this in a car booty 3 years ago and only used it 3 or 4 times,got it for £12.

You can see this will do the job nicely as it detaches from the plunger base.

:wink:


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## RussianRouter (20 Jun 2010)

WoodAddict":2levuw8j said:


> I've planning one of these for a while now. have a look here mycncuk.com



Hi Paul...eck another Paul :? :wink: 

I'll sift through that site later,need some shuteye soon.

Cheers.


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## CNC Paul (20 Jun 2010)

George,

I forgot to mention these people http://www.slidesandballscrews.com/axis ... l?cPath=58


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## stef (20 Jun 2010)

This has been a major project of mine for the last 6 months.. it's getting there though:










Table is 2000x1200mm. the x-axis is almost in place, and all the electronics+motors are sorted.


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## CNC Paul (20 Jun 2010)

Steff,

Thats a nice job, I like the chunky ballscrews. What design and control software will you be using ?


Keep us posted


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## RussianRouter (20 Jun 2010)

CNC Paul":3vix8w7n said:


> George,
> 
> I forgot to mention these people http://www.slidesandballscrews.com/axis ... l?cPath=58



Is there a catch there?,Paul.

An extra motor and driver for less than £200. Wow!


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## stef (20 Jun 2010)

I use EMC2 (Linux) , and CAMBAM to get the CAM files generated.
But then again, i am not set on any particular software, as long as it's free.
Ballscrews are 25mm diameter, 10mm pitch. 2 of them on the xaxis, 1 (1100mm) on y and 1 (400mm) on z .


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## RussianRouter (20 Jun 2010)

Paul,its basically a swindle,added it to cart and it started asking for motors added and the 2nd pair are expenive.


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## stef (20 Jun 2010)

if i may offer a little advice: dont rush your purchases.
no need to buy everything from the start (motors, screws, drivers, psu etc...)
motors are a standard format, nema 23 or 34 usually, so you can build the machine without buying anything too expensive.
or wait for the right deal on ebay.
i managed to get my hands on some gecko G202s, for around £50 a piece. They are far better than the leadshine on offer from zapp.
i got them last week.. and you've seen how far i am in the build !

it's tempting to fork out for good screws, good motors, good drivers, and then 
have them sit in a garage for 2 years, before decided to sell them at a loss !
start designing, then building. the buying is the easy bit, you can leave it until the end. 

well, that's my advice anyway.


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## RussianRouter (20 Jun 2010)

What do you reckon on this,Stef

http://cgi.ebay.co.uk/3-Axis-CNC-Router ... d4fefabc6d

I'm not after a super machine but one that is capable of handling a small bed.


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## stef (20 Jun 2010)

looks cheap enough.
but as i said, those are plentyfull.
i'd first consider what type of design you want (moving bed or gantry based)
then start making it.
the screws and linear bearings/guide, are far more crucial than the motors and drivers.
but then it's also a good idea to keep final costs in mind. but dont rush in buying the last pieces of the puzzle before you've even laid out the first.
imagine, you come across dirt cheap screws and rails in the next month, but turns out your motors are just a bit on the small side...
if you wanted to do this by the book, you'd have to workout the loading on each motor, before actually buying it. and this loading will depend on the screw, the type of design, the type of rail, etc...
plugging the motors to the controller and get them stepping took me 2 hours. building a small machine is likely to take you about 2 months.
i'd also consider quality of the rest of the equipment. if it's for a poorly built MDF machine with M8 threads as screws and ball bearing guides, then yep, those drivers are of equal quality. 
but if you intend to invest in decent screws and guides, forget about those drivers. get some Geckodrives, or at a minimum, some leadshines.
I built the drivers myself on my first machine (based on L297s), and i can tell you that they can make or break a machine. for the big machine, the one on the picture , i was prepared to pay over £600 for the drivers, that's what i budgetted for. then i got a bargain of ebay !


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## RussianRouter (20 Jun 2010)

http://www.youtube.com/watch?v=MLTAeE6j ... re=related


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## stef (20 Jun 2010)

a machine like this looks extremely accurate.
may be small, but probably decent screws and rails.

I am hoping for this sort of precision on mine. hope i will achieve it !


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## RussianRouter (20 Jun 2010)

Stef if you don't mind me asking what is the work it will be undetaking?

I think a flatbed and an overhead gantry adds to its versatility.


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## stef (21 Jun 2010)

RussianRouter":353wg6aw said:


> Stef if you don't mind me asking what is the work it will be undetaking?
> 
> I think a flatbed and an overhead gantry adds to its versatility.



It will be mainly for wood.
but it should be capable of aluminium and possibly steel.
the configuration depends on the size, mainly. above a given size, a moving gantry makes more sense than a moving bed.


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## wobblycogs (21 Jun 2010)

I hope your going to post loads of pictures RR - really looking forward to seeing how this project pans out. 

I've been planning to build a CNC for years, as soon as I get the bathroom I'm working on finished and the router table is built I think I'll probably start. I've always said that I'd build a gantry type design. The gantry design feels more complex to get right but the smaller foot print is a real bonus.


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## chipchaser (21 Jun 2010)

Hi George,

I don't know whether you have found this site yet, the link takes you to the Fora

http://www.cnczone.com/forums/index.php

It may not be the best site in the world, although I believe you can find almost everything you want to know there and it must be the biggest - what else would you expect from the USofA  

You can see many types of machines, lots of discussion of the pros and cons of alternative machine layout and there are various plans, some free. I mainly visit the Woodworking Machines Forum.

If you are thinking of self building it may also be worth looking at

http://www.solsylva.com/

Even if you don't buy his plans there is a lot of good info there. Oh, and I like this one too especially the chain drive for a long movement axis.

http://buildyourcnc.com/default.aspx

HTH and apologies if you've been there before.

Graham


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## stef (21 Jun 2010)

that's my build log, on cnczone.
http://www.cnczone.com/forums/showthread.php?t=101685


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## RussianRouter (21 Jun 2010)

wobblycogs":3d7m2qjn said:


> I've always said that I'd build a gantry type design. The gantry design feels more complex to get right but the smaller foot print is a real bonus.



With a lot of searching and looking the gantry is essential to the lift of the cutter away from the job,I've seen partial builds on you tube that are going to fail at the first hurdle because they have not implemented the Y axis.

Its pretty straight forward and there's a couple of ways in doing the gantry slide,however as mine won't be as large as Stef's the princple is the same on a smaller scale...just less movement of the cutter in the X and Z axis depending on the width length.of the bed.

The width of the bed on this bed will be 24" about 30 ?" I'll decide on the build when it starts.

I'm trying to keep the cost down to a minimum without losing stability and accuracy.


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## RussianRouter (21 Jun 2010)

chipchaser":eht7lqxp said:


> Hi George,



Thanks Graham.

Been on more sites than you can imagine over the last couple of days searching for design inspiration,last night I must have spent 2 hours on youtube browsing and watching the homebrewers machines.

There are some real idiots out there,a guy was using his hand power drill on his effort as the cutter. :lol:


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## stef (21 Jun 2010)

RussianRouter":11g5eld9 said:


> wobblycogs":11g5eld9 said:
> 
> 
> > I've always said that I'd build a gantry type design. The gantry design feels more complex to get right but the smaller foot print is a real bonus.
> ...



sorry to break it to you so bluntly, but it's not that straight forward.
eventhough i conceide that going smaller than mine will spare you a lot of hassle. 
one of the main thing you will be fighting is flexing of your support. leveling and squaring is also another big issue. there are flex calculators on the web that will help you choose the right material/profile for the frame/structure. but you just cant pop into b&q and pick up any piece of material. not if you want accuracy.

If it's a hobby machine, only to be used in a dry environment, then MDF is fine. as long as you build in torsion boxes and a clever frame.
if it's a advanced hobby, and in a garage, then it's steel or aluminium. even with steel, balancing things out is a little tricky.
you will need to "machine" or flatten all the beams onto which guides are resting.
dont expect to spend less than £1k on a 24x24 machine. that's if you want to machine aluminium.


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## RussianRouter (21 Jun 2010)

Hi Stef

When I say accuracy I mean within a tolerance factor,yours will be precision becaue ofthe nature of the work you want.

I'm building this fo one reaon and that is to cut out shapes and carvings to affix to wood or inlay in wood,it is not being desinged for doing dovtail or any other joint but I'll see how it fairs with a couple when I get my head round operating the software.


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## stef (21 Jun 2010)

RussianRouter":2huwaxdi said:


> Hi Stef
> 
> When I say accuracy I mean within a tolerance factor,yours will be precision becaue ofthe nature of the work you want.
> 
> I'm building this fo one reaon and that is to cut out shapes and carvings to affix to wood or inlay in wood,it is not being desinged for doing dovtail or any other joint but I'll see how it fairs with a couple when I get my head round operating the software.


fair enough.
you still have to be carefull though. my first machine (salvaged most parts, ball bearings as guides, M8 as leadscrews) still cost me over £300. I had to give up tweaking it, because it was just not right from the start. it would move the router fine, but when you cutout a shape, you never do it in one pass. the software works out for you that you need overlaying pass, say 5 times 2mm for a 10mm deep cutout. if your machine is not spot on, if it misses steps, or wobbles a bit, then the 5 overlaying pass are not on top of each other, and the piece is messed up.mine messed up so many times, it would take me 5 pieces to get one right.

It really isnt a job to be taken lightly, and if you really want/need results, then spend on good quality components. if you just want to have a go and see what you can do on a budget, then it's a different game.


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## RussianRouter (21 Jun 2010)

Ok lets see if I've got this right in my mind?

Duh! didn't think that one through,sorry

I'll have a rest. :lol:


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## stef (21 Jun 2010)

RussianRouter":p854w5jt said:


> Ok lets see if I've got this right in my mind?
> 
> Lets supposing I'm making a box 12"x8",I want a dark oval shape inlay in the lid of the box.
> 
> ...



I am not sure if i follow your plan to inlay the wood.. did you take the diameter of the bit into account ?
re: the number of passes,it will depend on the thickness of the wood, and how hard it is.
Think about routing like you would handheld: your machine may not even be as strong as you holding the router, so you have to go easy on it: to cut through a 10mm plank you will probably want to make 5 passes, 2mm each time. each pass is on top of the previous one, in theory. except that to achieve this, your machine has to be pretty precise (repeatability). it's easy for a stepper motor machine to be loosing steps, either from the electronics, or lack of power, or some mechanical gremlin, etc..backlash is probably the most obvious reason why the two passes wont be on top of each other. which is why you generally have 0 backlash nuts on these machines..

overall, designing a cnc is to make massive amounts of compromises. even if cost isnt an issue, you will still have many compromises which will get sorted depending on your specific application.
you can have tall gantry, small legged gantrys, twin screws, single screws, steppers, servos...


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## chipchaser (21 Jun 2010)

Hi Stef,

That looks very good, impressed by the steel frame. What accuracy are you aiming for with this one? 

What did you make your first one from and how accurate was that?

Have you found EMC ok?

Look forward to seeing more of your machine as it progresses

Graham


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## RussianRouter (21 Jun 2010)

Forget what I said there,bit tired as I've only had 2 hours sleep out of 36. 

hence my pevious post.


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## RussianRouter (21 Jun 2010)

I'm looking to do something like this... :lol: :lol: 


http://www.youtube.com/watch?v=9lrLcDTa ... re=related


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## stef (21 Jun 2010)

(not a cheap machine this !)

here are some pics and video of my first machine (before the router was mounted .. but you get the idea !)


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## RussianRouter (21 Jun 2010)

Well I'm pretty sures omeone will take that off your hands if the price is right?

Nice one that.


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## stef (21 Jun 2010)

RussianRouter":2nw4otey said:


> Well I'm pretty sures omeone will take that off your hands if the price is right?
> 
> Nice one that.



I wouldnt sell it, it's a money pit, waste of time.
but it was a good first go at cnc, and i learned from it, like what not to do !
it is in bits at the moment, waiting to be picked up by my dad. he likes that sort of things, and i got the motors from him in the first place !

At the end of the day, a waste of £300.
conclusions from that machine were:
-be very very accurate.
- all screws and driving nuts need to be very accurately aligned and adjustement provided for if alignement cant be achieved first hand.
-use stiffer material. this was aluminium section, stuffed with MDF to make it stronger and stop bolt/nuts compressing them flat.
- use proper motors for the size.
- ball bearing carriages are a pain to get right. getting 3 out of 4 to contact is easy.. but useless unless you get the 4th one too !
- dont DIY the drivers.
- plan before you build
.. and a few other stuff i learned along the way.


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## RussianRouter (21 Jun 2010)

Just got two motors and two controllers at £50 cheaper than what motion control would have charged without the vat and P&P ie £274 Total...Arceurotrade £175...what a saving

The vat was inclusive and P&P over £100 is free.  


http://www.arceurotrade.co.uk/default.aspx


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## RussianRouter (21 Jun 2010)

stef":1gjamexn said:


> -be very very accurate.
> 
> - ball bearing carriages are a pain to get right. getting 3 out of 4 to contact is easy.. but useless unless you get the 4th one too !



This is not the solution to a stable gantry,the best solution is Aluminium square/round block precision drilled hole and a precision needle bearing inserted on both sides of the block so that it glides up and down the rail.

I was tempted to go the way your bearings are situated but I knew that they would rattle along rather than glide.


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## stef (22 Jun 2010)

RussianRouter":n0j9f963 said:


> Just got two motors and two controllers at £50 cheaper than what motion control would have charged without the vat and P&P ie £274 Total...Arceurotrade £175...what a saving
> 
> The vat was inclusive and P&P over £100 is free.
> 
> ...



I got my motors from them too.
however, the controllers are not brilliant (they are leadshines under a new dress). so i waited.. and waited.. and got much better Geckodrives G202s for almost half the price !


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## stef (22 Jun 2010)

RussianRouter":34tatbwh said:


> stef":34tatbwh said:
> 
> 
> > -be very very accurate.
> ...


Dont know about the needle bearing. i got the ball bearing working very well on the y axis, and it was very smooth then.. however, i really struggled on the x axis, and there was always a spot were there would be some play in the gantry.

best solution, imo, is the one i have on the big machine. linear precision ground rails, with ball carriages.. expensive, but damn good !
supported aluminium rods is the next best thing, a little cheaper, but still good enough for wood.


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## RussianRouter (22 Jun 2010)

Hi Stef

Have you had a nosey at "SolidCam"? Ibelieve this is a good program for machining in 3d.


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## stef (22 Jun 2010)

RussianRouter":30v9op5t said:


> Hi Stef
> 
> Have you had a nosey at "SolidCam"? Ibelieve this is a good program for machining in 3d.


no, i havent heard of it, will check it out though.
It's a cam file generator, i take it ?


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## CNC Paul (22 Jun 2010)

RussianRouter":2cxx1bjn said:


> Hi Stef
> 
> Have you had a nosey at "SolidCam"? Ibelieve this is a good program for machining in 3d.



Have a look at Aspire and the other software by http://www.vectric.com/


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## RussianRouter (22 Jun 2010)

stef":14bf0p3m said:


> [
> It's a cam file generator, i take it ?



Yep,as the name suggest,watched a video on youtube of a guy that was using it to mill a front end of a train...marvellous, that link I posted here of the plaque being carved out was also done with the very same software.


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## chipchaser (22 Jun 2010)

Any idea of the cost of Solidcam? The dealers all say call for a price which makes me sure I can't afford it, a post on CNCZone mentions $6k.

Anyone use or recommend Cambam?

Graham


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## stef (22 Jun 2010)

yes, CAMBAM does the job, at least for 2D cuts. i havent tried it 3D


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## RussianRouter (23 Jun 2010)

Ok,here's something thats baffling me...Spindle speed and operation.

Hows this rigged up to the setup?do I have to wire the routers speed controller circuit?


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## stef (23 Jun 2010)

RussianRouter":1plog625 said:


> Ok,here's something thats baffling me...Spindle speed and operation.
> 
> Hows this rigged up to the setup?do I have to wire the routers speed controller circuit?


I havent worried about this yet.
from what i understand, you can have many different setups.
either your spindle has a analog speed input, like a voltage, or a digital one. you need some sort of interface with the parrallel port also (a DAC if it's an analog input). and finally, you need to configure the software to match your setup.
not straight forward, especially since spindle speed can be set by hand (that's how i do it)
I have hooked up a few relays for spindle on/off (TTL->24Vac->240V) but still need to configure the software to get it working. that seems simple enough.
for the machine power (motors PSU etc..) the control from the computer is a square wave (speed dependind on OS, but around 10KHz) and for that to get converted into a on/off signal, you need a charge pump circuit. I am still working on mine.


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## RussianRouter (23 Jun 2010)

Hi Stef

I'm thinking of going fo the more advanced breakout boards,especiallythe one fromHong Kongon ebay which i a whole lot cheaper than here and I don't think import duty will amount to much as its well below £100 even below £50.

It has a spindle speed built in to it.

If I do I think I'll be wiring the routers speed controller up to it? then it'll auto adjust in the software?


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## RussianRouter (23 Jun 2010)

£55
http://cgi.ebay.co.uk/NEW-4-Axis-TB6560 ... 2a07dfdee4

Or 37 for 3Axis
http://cgi.ebay.co.uk/NEW-3-Axis-TB6560 ... 27b2996571


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## CNC Paul (23 Jun 2010)

RussianRouter":235bo8w9 said:


> Ok,here's something thats baffling me...Spindle speed and operation.
> 
> Hows this rigged up to the setup?do I have to wire the routers speed controller circuit?



George,

I might be wrong, I don't think you can control a router from a breakout board. My HF spindles are controlled by a variable frequency drive which excepts a signal from my control box to change spindle speed through the control software.


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## chipchaser (23 Jun 2010)

hi George,

here is a thread on those boards from MYCNCUK

http://www.mycncuk.com/forums/showthrea ... ver-Boards

and another

http://www.mycncuk.com/forums/showthrea ... -tb6560ahq

and another 

http://www.mycncuk.com/forums/showthrea ... ght=tb6560

search in mycncuk for 

TB6560 

I got 8 results

Graham


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## RussianRouter (23 Jun 2010)

Hi Graham

I'll look in to it,I was pretty sure it could??

http://www.cncathome.com/vfd.html


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## chipchaser (23 Jun 2010)

Hello George,

Paul commented on spindle speed control not me but a very interesting link. So many useful sites out there  

Graham


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## RussianRouter (23 Jun 2010)

Hah yes,sorry for that Stef...erm...Grayham.  

Was having a look at one of those links about the breakout board.

Well the first link the guy was using a motor that was below the required amperage,it states quite clearly in the listings"This board should not be run with motors below 1.5amp.

His motor was 1.4amps peak

Hmmm! would like to know if that chip that blew was the chip that driven the motor and if it was? then the motor has caused the damage?


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## RussianRouter (23 Jun 2010)

Hi Stef

Question for you.  

The place where I was obtaining the motors and controllers from,phoned me up this morning to tell me that the controllers are not compatible with the selected motors I chose,I didn't want to pay the extra for the right motors as I need to do this on a budget.

So what I did was order controllers and compatible motors ie I got three motors and twocontrollers because I was thinking of using two motors in parallel to work the gantry as the gantry does more work than the Y axis lift.

The motors will be either side of the bed to even the load.

Does this make sense?


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## stef (23 Jun 2010)

RussianRouter":18kq7q93 said:


> Hi Stef
> 
> Question for you.
> 
> ...



um. possibly not.
you need 1 controller per motor (if everything is dimensioned properly)
you could poussibly drive 2 motors from one controller (say 2 x 2A/phase motors from a 7A controller) But my guess is that this will be very troublesome.

what i find strange is that the controllers are not compatible with the motors you choose...they should be, they are universal controller, afaik.


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## RussianRouter (24 Jun 2010)

stef":2vd1ffb9 said:


> what i find strange is that the controllers are not compatible with the motors you choose...they should be, they are universal controller, afaik.



The motors and controllers both peaked at 4.2amps

Arc code160-010-00450
http://www.arceurotrade.co.uk/Catalogue ... per-Motors

And...the first driver onthis page...
http://www.arceurotrade.co.uk/Catalogue ... er-Drivers


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## stef (24 Jun 2010)

RussianRouter":3uqrqqqr said:


> stef":3uqrqqqr said:
> 
> 
> > what i find strange is that the controllers are not compatible with the motors you choose...they should be, they are universal controller, afaik.
> ...



You can limit the curent to whatever you want it to be.
nothing stops you using a 7A driver on a 1A peak motor.

similarly, you can drive a 7A motor with a 1A driver... it just wont have much torque.


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## RussianRouter (24 Jun 2010)

stef":fdi9nhrk said:


> You can limit the curent to whatever you want it to be.
> nothing stops you using a 7A driver on a 1A peak motor.
> 
> similarly, you can drive a 7A motor with a 1A driver... it just wont have much torque.



This what I couldn't undestand when he said they're not compatible?

Surely if I set the driver to 3.6amps it' will only drive the motor at that amperage at max peak and at the same time stop the driver going over its peak amperage max.


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## stef (24 Jun 2010)

RussianRouter":3cfmu5ff said:


> stef":3cfmu5ff said:
> 
> 
> > You can limit the curent to whatever you want it to be.
> ...



absolutely.


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## RussianRouter (24 Jun 2010)

Ok,phoned back up and he said they will not sell the drivers and motors on that basis.

Anyway I have them here now,so I'm stuck with them. 

Didn't realise they were so heavy :shock:


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## stef (24 Jun 2010)

RussianRouter":2iw3hzmc said:


> Ok,phoned back up and he said they will not sell the drivers and motors on that basis.
> 
> Anyway I have them here now,so I'm stuck with them.
> 
> Didn't realise they were so heavy :shock:



very very strange..
which motors did you go for ? i have 4 of the 350Nm (near the bottom of the page). 2 for x, 1 on y and 1 on z.


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## RussianRouter (24 Jun 2010)

stef":2l97cvlr said:


> very very strange..
> which motors did you go for ? i have 4 of the 350Nm (near the bottom of the page). 2 for x, 1 on y and 1 on z.



They're the ones I originally went for but ended up with the 3x220Nm's


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## RussianRouter (24 Jun 2010)

The fun begins now,searching out wood in the outhouse and I'm making the gantry out of plywood as will the bed be also.

The bed will be 3/4" and gantry 1/2".

I chose plywood over MDF as MDF is quite heavy and the less weight we have on the movable parts of the project the less the motors suffer the load strain.

The construction of the project in wood won't cost me nothing as all wood I have came out of skips or dissasembled furniture. 

The only parts thats costing me is the mechanics and components of the build.

Next post will be pics of the gantry itself ie template,cutout and assembled?


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## stef (24 Jun 2010)

RussianRouter":1q9mdg12 said:


> The fun begins now,searching out wood in the outhouse and I'm making the gantry out of plywood as will the bed be also.
> 
> The bed will be 3/4" and gantry 1/2".
> 
> ...



be very carefull in your construction.
you need to be squarer than square. dont worry about the load on the "small" motors.
my first machine had 2 250mA motors, which were more than enough to move the gantry and the router up and down, with loads of power to spare. the third motor (on y) was half of that, so it struggled a bit.
stepper are deceptively powerfull !
i wouldnt worry about the weight of MDF over ply wood.. peanuts for the motors.
just use torsion boxes and strengthen everywere.


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## RussianRouter (24 Jun 2010)

Hi Stef

Thanks for that,until I spark up the motors I wouldn't have had a clue how powerful they are.

Wait till you see how I going to manage the linear rail I've sent off for these ball bearing inserts and I will be inserting them in 2"x2" blocks.

http://cgi.ebay.co.uk/10pcs-16mm-LM16UU ... 2c54ebf52c

These are exactly the same inserts as the manufactured aluminium ones the guy is selling...
http://cgi.ebay.co.uk/4pc-25mm-SC25VUU- ... 2a07e47044


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## stef (24 Jun 2010)

whatever you do, dont rely on unsuported rods.. they just dont work well enough.
they may be fine for a dremel bearing gantry, but not strong enough for a router.
my gantry was as light as can be, with a 1/4" router on top, (in fact, even without the router) and i had way too much flex in the rods.
they were only 600mm long.
Most people do complain about the flex in unsupported rods.


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## RussianRouter (24 Jun 2010)

stef":2cqt5mdy said:


> whatever you do, dont rely on unsuported rods.. they just dont work well enough.



I'm ahead of you on this one,Stef. 

I have devised a way round that and it should be done with all long length slide rails on a homebrew CNC.

The way round it is to have a double rail,since the gantry rely's on rail support only we implement one rail below the bed and another rail directly above this rail on top of the bed this way the weight is evened out and should not deflex the rail.


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## stef (24 Jun 2010)

ok, doubling the rail has been done to minimise flex.
then again, you are doubling the alingment issue. you need to align 4 parallel rods. trickier than 2 !
in terms of costs, i am not sure you would be saving much.
I'd say not my configuration of choice, but then , i havent tried it.

here are a couple of pix from my 1st machine taken 1h ago.
it shows the state its in ! 
also, what i wanted to show is the "bodging" i implemented to conteract flex.
because i have 45deg bearings, they not only push down on the rods, but also outwards. so i stuck some side supports (2 per side) connected by long threads across the machine. they are adjusted to that they push just enough on the rods.
finally, a close up of the rods.
they started a thick walled steel hollow tubes. they were not strong enough. so i stuck a M20 threaded bar inside, and filled the gap (1mm) with resin. the result is a pretty strong and heavy looking bar. 
well.. not strong enough ! they flexed much less, but still too much. It did not take much force to twist the gantry on the rods, which means trouble when machining harder woods.

anyway, regarding the motors, they are rated a 350Ncm..if you cannot visualise torque, imagine a 35Kg (5-6 stones) load onto a cable, on the shaft of the motor (1cm). the motor will hold in.
anything lighter, the motor will lift.
basically, unless you use a lever of some sort, you will not stop the motor turning with your fingers alone.
you probably need 10% of this with a mdf/ply machine. unless you have a 35Kg router !


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## stef (25 Jun 2010)

Here is a quick calculation i just did to try and show you what degree of flex you may expect:
i use a solid steel, 20mm diameter rod as your rail, youngs modulus is 210 000.
that gives us a Izz = of 15707 mm4
If i use a 1000mm long rod, and stick a 12.5Kg weight in the middle, i can expect about -0.2mm of flex.

if you use two bars, you can expect half of that, say 0.1mm.
the question is how heavy is your gantry (12.5 x 2 sides =25Kg is probably on the heavy side) and how much force can you expect from the spinning router. I'd imagine 25kg is probably not far of the mark.
anyway, expect 0.1mm of flex. probably ok for most wood work.
using a wider diameter bar would reduce this further.

all calculations are made from here:
http://pagesperso-orange.fr/philippe.fi ... poutre.htm
I know, it's in french, but you can probably find an english one somewhere !


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## RussianRouter (25 Jun 2010)

Hi Stef

I'm doing this in a manner whereby if it doesn't work out as planned then I won't lose much ie if the rails do become a problem? then all I have to do is omit the top rails(No big deal as they will be useful elsewhere) and replace with flat slidemounts but the bottom rail will stay to stop the gantry from swaying.

I would have pefered to construct a square tubular frame as I have some metal tubing, but my welding gear got stolen from the lockup garage I once had. 

When I next pass a local wrought iron gate welders shop I'll pop in and ask how much to weld a frame together which will be the same size as the present construction,not too big so it might not cost much to weld?.


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## stef (25 Jun 2010)

welding is doable.
a lot of people manage it.
it can be very very tricky though, as it's difficult to keep the frame 100% square. I bolted/weled mine partly for that reason, I couldnt weld it accurately enough.
People who weld CNCs usually use a engineer level (precise to 0.1mm/m or better) to check on the frame. Then it's a question of shimming, braze filling and skimming to get the bumps out.
overall your approach (double rods) may work very well, but be aware that 20mm diameter is borderline if you want to achieve sub 10thmm accuracy.

I hope i am not making it sound more difficult than it is ! 
it's not difficult, but it requires carefull planing !


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## RussianRouter (25 Jun 2010)

Here's the sides of the Gantry....

Template.
Cutout.
Finish with the router.


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## RussianRouter (28 Jun 2010)

Was phoning around for a quote on a square tubular frame made up from mild steel for the CNC bed,quotes were in the region of £45 to £50 for a 24"x8"x34".

Didn't want to pay these prices and then I had a brainwave...eck! I have a computer desk here that I'm wanting to get shut of...

Use its legs and crossbars to construct the bed...bloody great innit when you get the light glowing in your head. :lol:


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## RussianRouter (28 Jun 2010)

Marvellous what you can do with a CNC,most builders have added a fourth axis,this axis holds the Lathe head. 

http://www.youtube.com/watch?v=9eZdY6_8 ... re=related


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## stef (29 Jun 2010)

good idea regarding the desk. just check it's square. it's bound to be better than the local welder, if it's done industrially.

here are my gantry sides. 20mm aluminium


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## RussianRouter (29 Jun 2010)

Thought you had emigrated,Stef.  

By eck! Aluminium must be darn cheap over there in Normandy?

Did you have those made?


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## stef (29 Jun 2010)

no, i machined them myself, from salvaged aluminium.
cost is about 2.50 per kg. these pieces are 5.5Kg a piece. so roughly £25 for the two side. relatively cheap.
the thing is you cant really do this halfway. there is no point spending £500 on precision rails, if you are going to mount them on nasty mdf.

so far, the build is consistent, i should have the gantry up this week.


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## RussianRouter (29 Jun 2010)

Very nice job you done with them,you have a mill,Stef?


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## stef (29 Jun 2010)

RussianRouter":pvzwcvqm said:


> Very nice job you done with them,you have a mill,Stef?


no, not yet !
i used an angle grinder, jigsaw, hacksaw, belt sander, files, drill, and my eyes !
took me a full day to cut them right !
but i am pleased with the result.


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## RussianRouter (29 Jun 2010)

Got cheap wood chop saw out the car booty sometime last year and didn't have intentions of using it as a wood chop saw.

Took the blade off,threw it away and replaced with a 230mm? cutting disc,cuts metal perfect


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## scouse12345 (21 Aug 2010)

What's the latest fellas, was following this with interest..?>

scouse


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## Dibs-h (21 Aug 2010)

scouse12345":p2r43046 said:


> What's the latest fellas, was following this with interest..?>
> 
> scouse



George don't visit no more.


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## chippy1970 (21 Aug 2010)

Dibs-h":202pc52i said:


> scouse12345":202pc52i said:
> 
> 
> > What's the latest fellas, was following this with interest..?>
> ...



Yeah I thought I hadnt seen anything from him lately


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## stef (20 Nov 2010)

I have made a little progress
lets hope this video works...


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## Fecn (20 Nov 2010)

Just stumbled across this thread - I'm still mildly around - I check in on UKW about once a month, but as I haven't been doing any woodwork lately, I haven't had much to post on here. My current project is converting an old electric wheelchair into a robotic wheelbarrow thingy... I thought I should post on this thread though just to say 'keep up the good work' to RussianRouter and Stef.


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## stef (30 Jan 2011)

my CNC is nearly complete now:




I have all three axis running, and the spindle is almost operational. It requires water cooling, and that's not 100% working yet.
the spindle is a 24000rpm 2.2Kw fully enclosed three phase motor.

















I am so far very pleased with the results. It runs smoothly at decent speeds (enough to get your heart rate going, if the spindle was running !) without any major tweaks. It will still need about 3 months of adjusting and sorting things out, like the cutting bed, the cable carriers, and fixing various bits to be frame.
but i am hoping to cut my first chips in february.

I'll try to post a video later today.


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## stef (30 Jan 2011)

as promised


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## ginsters (30 Jan 2011)

neat stuff 8) 
amazing what you can build in the garage!
it reminded me of this for some reason http://www.youtube.com/watch?v=rJDztqCG91g :roll: il grow up one day


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## wobblycogs (31 Jan 2011)

Wow, that's probably the best looking home-made CNC's I've seen, you should be really pleased with it. I'm sure I speak for a lot of people when I say: got any more build pictures? 

You've got me dreaming about the day when I'll have the space and time to start my CNC project now ...


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## stef (6 Feb 2012)

a year on now, and since my workshop is now almost complete, so is the CNC router.
here are the latest pics, with the first cuts. so far, very pleased with it. it seems to be very repeatable. runing twice the same 45min long program ending doing exactely the same cuts !
http://s47.photobucket.com/albums/f168/ ... _small.mp4


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## stef (6 Feb 2012)

trying to embed the video..


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## Dibs-h (6 Feb 2012)

Stef

How many hours have you got in the building of it? Would you mind me asking what the total cost (money) is so far?

Cheers

Dibs


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## stef (6 Feb 2012)

Dibs-h":2giwth9h said:


> Stef
> 
> How many hours have you got in the building of it? Would you mind me asking what the total cost (money) is so far?
> 
> ...



building took 2 years, on and off, with a lot of other work in parrallel.
cost is probably over 2200 pounds, excluding some equipement i had to buy to make it (welder etc..)
i am not expecting to spend any more than that, except maybe for some precision measuring equipement for the calibration, and a water pump to replace the washing machine pump i am using now.


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## wobblycogs (6 Feb 2012)

Nice piece of kit you've built there Stef, well done. 

Is the main CNC motor your using one of those ebay Chinese jobs that comes with an inverter? Looks a lot like one of them, if it is how have you found it?


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## stef (6 Feb 2012)

wobblycogs":3w3ej0fk said:


> Nice piece of kit you've built there Stef, well done.
> 
> Is the main CNC motor your using one of those ebay Chinese jobs that comes with an inverter? Looks a lot like one of them, if it is how have you found it?



yes, almost.
the spindle is indeed the 2.2kw chineese 3 phase 24000rpm 400Hz motor.
however, the inverter is a more robust ABB unit.

so far, pleased with the motor.. but it's only been running 4-5 hours.


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## Dibs-h (6 Feb 2012)

Thanks for the info Stef.

Cheers

Dibs


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