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CNCKitMan
03-01-2017, 02:57 PM
Well I've been told to start a build log for a Cheap n Easy CNC with cutting area of 900mm x 900mm.
As I would like to turn this into a kit a some point I'll stick up what Ii can for criticism.

Clive S
03-01-2017, 03:26 PM
Well I've been told to start a build log for a Cheap n Easy CNC with cutting area of 900mm x 900mm.
As I would like to turn this into a kit a some point I'll stick up what Ii can for criticism.

I don't think I told you but suggested it :thumsup: But please don't be offended by what you get in feedback as it is all meant in good faith.

You will need to state what your aims are ie what you want to cut with it etc

Good luck with the build.

CNCKitMan
03-01-2017, 03:32 PM
No hard feelings fella, it was a little blunt . I'd love to know what the problem you see me encountering. as i may be able to pre plan away the issue before it arises.

I've just been giving the DL on past posts which makes everything clear now.
I'm not planning on disapearing but to produce. hopefully i'll have something to show you sketch wise shortly.

CNCKitMan
03-01-2017, 04:37 PM
20178

Real Crap Basic idea of what i'm looking to do.
In regards to general shape and approx motor placements, bearing guides etc.

A_Camera
03-01-2017, 04:40 PM
Well I've been told to start a build log for a Cheap n Easy CNC with cutting area of 900mm x 900mm.
As I would like to turn this into a kit a some point I'll stick up what Ii can for criticism.

Don't worry about the criticism. Of course start building one. It is great fun, and you learn a lot. I started off with the same ambitions also, building a cheap one, which in theory is easy.

I started with buying an infamous blue card + three NEM23 motors and a PSU and a DC spindle motor. I bought that blue card because I knew I could make it work (I am an electronics engineer by trade), if it is really as crappy as it's rumour says. After cutting a few meters of aluminium profiles, drilling some holes and bolting all together I realized that it is going to be too weak... and my project stalled because I was not sure I wanted to pay what it costs to buy better material, mainly because I was a bit unsure about being able to finish it.

...then one day I decided to continue, bought better material, and after a few months managed to finish a working version one. It was not something to write home about, but it worked and it proved my own abilities. Used "curtain rods" i.e. unsupported rods as linear slide, used M12 stainless steel screw rods and made my own nut to get zero backlash. I knew it's weaknesses already when I decided to make it, but I accepted them because I just wanted to know if I can make it work.

I realized that it was great fun both to use and to make the CNC, so I continued, decided to upgrade and basically converted the whole machine. New electronics, new spindle, new linear rails, ball screws, PSU as well as a considerably more rigid frame. So, basically now I am on my version three and now I am happy with it. It is not a beauty, but it does what I intend to use it for and it does it very well.

Costs? Well, I stopped counting a long time ago. It's a hobby, so costs doesn't matter as long as it is not tearing on the family economy. Never the less, it did definitely cost more than £1800 so far, I am very sure of that.

BTW, mine is a fixed gantry type, the table moves in Y direction and the Z slides across the table in X direction. I chose this type of design because it gives better rigidity and is easier to build a high quality machine this way.

CNCKitMan
03-01-2017, 04:48 PM
Thanks for the kind words!

My end goal is to have a vertical sheet sized machine (not any time soon)

I'm prototyping with ply (had plenty) but have seen them seemingly made from MDF and sold?
So i'm aiming for some sort of inner repeating pattern to establish rigidity without excess weight.

I'll keep every comment in mind as i muddle through.

Thanks Again!

CNCKitMan
05-01-2017, 07:55 PM
Whoopie today my first set of u groove bearing's turned up. Also by a stroke of cheeky luck I scored 4 1.2m mild steel equal angles for free. After 10mins of tinkering I'm now rolling x and y. Still wait for my couplings and sprocket's.

Clive S
05-01-2017, 08:31 PM
Whoopie today my first set of u groove bearing's turned up. Also by a stroke of cheeky luck I scored 4 1.2m mild steel equal angles for free. After 10mins of tinkering I'm now rolling x and y. Still wait for my couplings and sprocket's.

How about some pics, anything in cad yet?:encouragement:

Boyan Silyavski
05-01-2017, 11:22 PM
Hmm, kit, 900x900? What made you choose that working area? Thats something new.

CNCKitMan
06-01-2017, 10:56 PM
Hmm, kit, 900x900? What made you choose that working area? Thats something new.
Parts I had laying about mainly. I wanted to have a decent size as prototype for when I repeat if successful for a full sheet cutter.

CNCKitMan
06-01-2017, 10:58 PM
How about some pics, anything in cad yet?:encouragement:
Yeah I have a few SVG of what I'd like to do.
But been playing with concepts before I spend any more money. Have taken some photos of my mess.

CNCKitMan
06-01-2017, 11:01 PM
20260
20262
Bad pictures yes. 2nd x axis rail not in use atm.
But it will have one. Y axis both rails in place.

Clive S
06-01-2017, 11:30 PM
Well its different, it will be interesting to see it cut :applause:

CNCKitMan
06-01-2017, 11:41 PM
Well its different, it will be interesting to see it cut :applause:

Well she moves real smooth. But it's nowhere near put together. It's literally clamped down.
Waiting for couplings as had to test with cordless drill. Which worked a treat.

njhussey
07-01-2017, 12:18 AM
From the look of your sprockets and chain you'll not be doing anymore cycling...😁

Sent from my HUAWEI VNS-L31 using Tapatalk

CNCKitMan
07-01-2017, 01:03 PM
From the look of your sprockets and chain you'll not be doing anymore cycling...😁

Sent from my HUAWEI VNS-L31 using Tapatalk
Rofl

4x free wheel sprocket £2 or free of you have shed load of spare bits like I do. As for bike rides here's a pic of my little bike. Also the results of stupid tinkering.

20280

Robin Hewitt
07-01-2017, 01:18 PM
The tricky thing with chain drives is that the smaller sprockets give you terrible cogging and the larger sprockets give you enormous travel per rev requiring expensive low backlash gear boxes to get any king of resolution.

CNCKitMan
07-01-2017, 01:40 PM
The tricky thing with chain drives is that the smaller sprockets give you terrible cogging and the larger sprockets give you enormous travel per rev requiring expensive low backlash gear boxes to get any king of resolution.

Totally get that! Been doing countless searches on Sprockets and sizes to see what method would be best to resolve travel distance to rotation. Thinking i'd use some sort of gearing to compensate.

small drive cog on stepper to a large cog attached to my "control bar" which would equal a zeroing out of the exterior cogs that connect to the chain.

CNCKitMan
07-01-2017, 04:48 PM
How about some pics, anything in cad yet?:encouragement:

20285

OK so i'm real crap at using sketch up.

Clive S
07-01-2017, 06:14 PM
If you are serious at this you could design in Fusion360 it is free for hobby use, a big learning curve but it has CAM built in so you could use for generating the gcode later on.

There are plenty of tutorials on it. like https://www.youtube.com/playlist?list=PL9tn9rGywKUUGyeBWX5Alt9yzBIp84sD8

CNCKitMan
08-01-2017, 07:26 AM
If you are serious at this you could design in Fusion360 it is free for hobby use, a big learning curve but it has CAM built in so you could use for generating the gcode later on.

There are plenty of tutorials on it. like https://www.youtube.com/playlist?list=PL9tn9rGywKUUGyeBWX5Alt9yzBIp84sD8

20305
Something like this

magicniner
08-01-2017, 01:46 PM
Is there a particular reason you've chosen chain and not toothed belt?

- Nick

CNCKitMan
08-01-2017, 02:00 PM
Is there a particular reason you've chosen chain and not toothed belt?

- Nick

It's just what I had laying about. To be honest may end up using timing belt. If I have too many issues getting cogs for the chain.

Didn't like the price of the correct screws and had problems finding in the final size I want.

As for the belts I could find plenty but already had plenty of chain. I'll have to gear down the ratio between the stepper and the x axis cog control arm. Which as far as I can tell will be easy enough and provide even more torque.

CNCKitMan
20-01-2017, 03:09 PM
Yep I'm still here. Just been debating and waiting on parts.
so i've been dicking about with my moch up as i learn better in the physical.

So then i had my Y Axis working. I used a toothed belt after someone asking why not.
Now i know why not. Me! I'm soooo lazy. A chain can be a length or a loop real easy. Belt not so much.

Then I worked on my X axis movement.
Had to get creative as no coupling have turned up so far! Annoyed YES!

But i had hit the weight limit for the cheapy motors i had. :(
No drama

All is not lost.

njhussey
20-01-2017, 03:24 PM
But i had hit the weight limit for the cheapy motors i had. :(
No drama

All is not lost.

Don't forget you'll need plenty of power spare for the cutting forces, not just moving the axis about...



Sent from my HUAWEI VNS-L31 using Tapatalk

CNCKitMan
20-01-2017, 03:55 PM
Don't forget you'll need plenty of power spare for the cutting forces, not just moving the axis about...



Sent from my HUAWEI VNS-L31 using Tapatalk

Yes brother. I spotted that. Turns out my gantry is a little heavy with the rails I aquire.

Put a shirt tty Lil dremel style tool on it as a "let's see" . Getting a first eye on the forces and how/what they do and where.

What do you think of the flat rails and the supported bar rails which being best.

CNCKitMan
31-01-2017, 06:37 PM
OK so where am I.
After the weight limit issue. Rather than buy more powerful motors I scaled down.

Now have a rag tag machine with all 3 working axis.
No spindle as of yet, not even my test tool.

Videos and photos to come soon.
Brace yourselves as she's proper ugly.

magicniner
01-02-2017, 01:29 PM
A chain can be a length or a loop real easy. Belt not so much.

A belt can be used as a cut length as easily as chain, if you need a continuous loop then you will need to use an off the shelf size which can mean you need to make your mounts to allow adjustment of pulley spacing, but smooth drive, lower energy losses, and reduced wear and maintenance really can make the effort worthwhile,
Regards,
Nick

CNCKitMan
03-02-2017, 02:03 PM
Yeah I hear the looped belt i know you can by them presized. That's my issue right there as i would have need to buy several due to how i don't plan most things. Hey it's how i work!

The chain however i can shorten, lengthen, loop or otherwise with ease. the CON being finding sprockets for the Stepper.

CNCKitMan
07-02-2017, 06:51 AM
OK so over the weekend, I had my mate (kids in tow) come round and we tinkered with the CNC mockups.
After which i had one quick upgrade and now i have an almost fit for purpose machine.

I still want to replace 80% of the parts (as i'm a bad carpenter)
Photos and Video to follow.

CNCKitMan
08-02-2017, 01:11 AM
The Test
20689
20688
First Upgrade
20690
Not the best photo I know. But she's ugly and I didn't want to break me camera even more. Had me a sticky x axis, turns out that my base was slightly bowed. Will make a table for it to have all straight and on the level. Yes it cuts and more than cake.

njhussey
08-02-2017, 02:15 PM
Well it certainly ain't pretty....but looks like it cuts and if it does what you want it to do then fair play to you :wink:

Clive S
08-02-2017, 02:39 PM
OK so over the weekend, I had my mate (kids in tow) come round and we tinkered with the CNC mockups.

Well its good that the kids are leaning something instead of watching telly and it isn't costing too much. It will be interesting to see how you evolve it.:thumsup:

CNCKitMan
09-02-2017, 03:55 PM
Well it certainly ain't pretty....but looks like it cuts and if it does what you want it to do then fair play to you :wink:

Thank you bro!

She so UGLY the bag i put over it up and ran away, leaving me a note stating it was cruel and unusual punishment.
I had to agree!

She's going to get upgraded slowly.
Then i'm going to refine a few parts, re cost and send a kit version to my friend in Scotland.

If that goes together and works out the box then i'll think about offering to others.
But they won't be ugly things like this is now.

Shes that ugly due to she costing £100

JoeHarris
09-02-2017, 11:15 PM
Thank you bro!

She so UGLY the bag i put over it up and ran away, leaving me a note stating it was cruel and unusual punishment.
I had to agree!

She's going to get upgraded slowly.
Then i'm going to refine a few parts, re cost and send a kit version to my friend in Scotland.

If that goes together and works out the box then i'll think about offering to others.
But they won't be ugly things like this is now.

Shes that ugly due to she costing £100

Surely that spindle and mount alone cost more than £100? You've not convinced me to buy one just yet, but you have it moving which is more than I can say for mine which has not been cheap or easy!!


Sent from my iPhone using Tapatalk

CNCKitMan
10-02-2017, 06:08 AM
The kids thought it was amazing! but they are 4 and 7!

CNCKitMan
10-02-2017, 06:17 AM
Wassssson JR!

I'm not convincing anyone i don't work like that. You will or you won't is my level of sales, lol.

As for my cost
The Spindle is a POO! one that i have on it ATM. Came with a 80mm bracket. - £50
Controlling Motors (Arduino, Board, Stepper Drivers) £20
Ball Screws, bearings and nut £18
Steppers £30
2nd Hand Rails £2

So i'm sorry i under stated! by £20
£120 In total

wood, screws, bearing n bolts (free)
:thumsup:

CNCKitMan
15-05-2017, 11:53 PM
I'm still alive.
Okay so I've built, destroyed, re-built over and over.
This is where i am now.
21656
21657
21658

CNCKitMan
15-05-2017, 11:59 PM
21659 Combine Shot!

CNCKitMan
16-05-2017, 12:00 AM
Nah bro, Spindle Mount and Controller £50

Clive S
16-05-2017, 07:22 AM
Well nobody can say you are not a trier and hope that your kids are still excited with it:welcoming:

CNCKitMan
16-05-2017, 09:13 AM
Well nobody can say you are not a trier and hope that your kids are still excited with it:welcoming:

True dat! all made from scrap wood, it's flat and cuts straight.
just waiting for my replacement spindle.
gotta change gantry then if i'm happy i'll make a non scrap version.

njhussey
16-05-2017, 09:23 AM
I'm still alive.
Okay so I've built, destroyed, re-built over and over.
This is where i am now.
21656
21657
21658

Good that you're still going with it, your gantry looks well out of square in pic 2!!

CNCKitMan
16-05-2017, 09:48 AM
yeah its not mounted right. but need to make a better one anyways.

CNCKitMan
10-09-2017, 01:46 PM
WASSON! OK so i've stalled HARd! on the re-build of my sheet cutter CNC with aluminium frame.
Whilst we are waiting for that i built 2 small 450mm x 450mm cutting area machines using belt drives.
One's at my mates being abused so no pics there but here's the other one (waiting on the post for parts)

photos to follow

CNCKitMan
10-09-2017, 01:51 PM
22776

This still has to have the Z-Axis on it but parts not here yet.

ravihotwok
11-09-2017, 08:57 AM
starting to look really good mate

CNCKitMan
11-09-2017, 01:08 PM
Why thanks bro, from the Frankenstein beginnings to my little neat one, it's been loads of fun.
When you see my sheet cutter you'll see the neatness hasn't made it that far.

I had a quick browse of your build log. looks like your making head room.

BTW i know Nout just like you, however it seems it's not as hard they say.

ravihotwok
11-09-2017, 02:20 PM
Cheers, yes there is a lot of foreign terminology which is really hard to understand, but im slowly getting there just trying to get my setup finished. Really is a lot of fun though and learning so much every time a spend a few hours on my cheapo machine

CNCKitMan
11-09-2017, 10:14 PM
Yeah, I felt the same. I'm not one for terminology. but sure is fun!

Desertboy
12-09-2017, 11:23 AM
I admire your persistence but the fact you've moved to an aluminium frame was something I knew you would from the first post I read of yours. MDF/wood has just too much flex and also aluminium 10 years later is still aluminium MDF could easily be a mush.

I started my build very much like you (except that I was always going to have aluminium frame) but as I got to the end you start to realise there is a reason everyone tells you to get Hiwin's style rails and ballscrews because they work and they work well.

Cheap (Sub £1000) and decent router are not words that go together.

CNCKitMan
12-09-2017, 12:00 PM
I admire your persistence but the fact you've moved to an aluminium frame was something I knew you would from the first post I read of yours. MDF/wood has just too much flex and also aluminium 10 years later is still aluminium MDF could easily be a mush.

I started my build very much like you (except that I was always going to have aluminium frame) but as I got to the end you start to realise there is a reason everyone tells you to get Hiwin's style rails and ballscrews because they work and they work well.

Cheap (Sub £1000) and decent router are not words that go together.

ROFL, I love you man. But me thinks you got me wrong.
The aluminium frame in the photo is 1 of two of my baby CNC's
I still use my large wooden one and am making a aluminium one just because i can.

My wooden machine is Ply and Timber i used MDF to prototype parts (cheap stuff).
SO far cuts Hard and soft wood, perspex and slate.
Think That Qualifies as Decent?

I was going to use a chain drive but could find the parts i wanted so ended up ball n screw.
as for the rails My lovely door runners have held out and work like a cool summer breeze.

Router/Trimmer £40
Rails n Wheels £70 ish 120cm
Screws n Bits x3 £40 ish 100cm
Stepper Motors x4 £100
Drivers x4 £30
Controller £20

£300 as wood was all scrap i had that didn't cost me anything.
I Think that qualifies as cheap?


So my Cheap CNC Router is Decent ! lol look all three words in yet another sentence.

Boyan Silyavski
12-09-2017, 01:26 PM
Of course depends on what qualifies as "precision" and "repeatability" for you. What you have done so far is in the 1-2mm region at best. if that suits you, then great. Most people trying to make a machine aim at least 0.1mm, the good builds aim at 0.05mm, exceptional builds can achieve 0.01 mm.

PS. I am talking "all over" not "absolute". I don't think possible to achieve absolute precision better than 0.05mm. Where "all over" means when you measure a machined element and "absolute" meaning at each point in the working area.

CNCKitMan
12-09-2017, 01:36 PM
All jokes aside.

Yes over the years all metal will out last wood.
and i like ball screws over belts n stuff.
i'm just not on the page that you have to use this or that type of this or that.

CNCKitMan
12-09-2017, 01:50 PM
Hey Bro,

My first big cutter (as i call it) She's made with no love, not much care and she's gonna die due to it.
Hence while shes working i'd thought i'll make another.

Shes pretty accurate as i'm always stopping and restarting my cuts (repeating ) due to something i forgot to add or take out.

Example would be this piece of old roofing tile, as they are not flat or even i had to repeat parts until they were closer to being the same depth.

22777