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jcb121
26-07-2011, 09:20 PM
So, what do you think of this design?

as it's the one I'm probably going to make.
42784277

Thoughts and constructive criticism welcome.

It's made out of 10mm thick ALu by the way and 20mm supported rails.

everyreasonto
26-07-2011, 10:48 PM
Hi, what do you intend to use the mill/router for? What is the cutting area?

Regards

jcb121
26-07-2011, 11:12 PM
A 1050watt Kress at the moment, Cutting Area it just over A3 and 100mm High.

Robin Hewitt
27-07-2011, 10:47 AM
Thoughts and constructive criticism welcome.

I like the triangles, you get a lot of strength from a triangle.

Can I suggest 2 small changes.

The X axis rails have a lot more vertical separation than there is separation on the ball bushings. This introduces an awkward turning force on the nut which the bushings are poorly placed to resist. Suggest you lower the top rail and screw somewhat. Allow the Z rails to overhang at the top you are only going up there for tool changes, keep the strength at the bottom where you need it.

Bolt the vertical risers to the sides of the Y axis aluminium sections. Connect the diagonal braces to the vertical risers with a lap joint not a mitre. Using an offcut from the vertical riser as packing, lap joint the braces to the aluminium sections. Maximise the rigidity the diagonals have to offer.

Incidentally, 1/2" thick aluminium bar is a lot easier to find than 10mm.

Jonathan
27-07-2011, 11:14 AM
I think the Y-axis rails should be mounted on something stronger, ideally both on a single piece. At the moment they're on something that will twist easily, so they will still deflect downwards...
Having them far apart is good I think, though I agree the ratio of the Y and Z rail seperations should be closer to one. Perhaps make the Z axis wider?

jcb121
01-08-2011, 12:16 PM
I have just received my DIYCNC Breakout board! :D

this may sound silly, but this is the first serial item I have ever used! I have to find an old PC now!

Also took delivery of some M6-M12 taps.

Exciting stuff.

The supported rails in that picture were 250mm Long and the screw was 350mm, this allowed me to mount the screw supports above and below the supported bearings making it thinner.
I'm now getting 300mm supported rails, this means that the screw supports will have the be inline with the rail and that the Z axis will be wider.

would changing the ratio of Z and Y closer to 1 make it more rigid? I thought it was a bigger the better situation!

the ratio of the new design is about 2:1

the 2 being the Y axis.

Jonathan
01-08-2011, 12:55 PM
I think that ratio is fine as both of the distances between rails are reasonable, so it surely can't be worse than if they were both the same as the 1.

What are you mounting the Y-axis rails on?

jcb121
01-08-2011, 01:02 PM
probably one large bit of Alu. due to the cost of this, i'll have to make the Y Axis rails closer together to make it cheaper! then it probably will be very close to 1:1

jcb121
01-08-2011, 01:15 PM
Any one know where I could find ALu 170x10x....

I'll have to check down fromstock later today :)

Jonathan
01-08-2011, 01:15 PM
One large piece is best, otherwise the rails will twist.

Try www.aluminiumwarehouse.co.uk

Imperial dimensions are more common, so you're after about 7"x3/8"... these are the nearest:

http://www.aluminiumwarehouse.co.uk/product_info.php?products_id=29030

http://www.aluminiumwarehouse.co.uk/Aluminium-Flat_Bar_-_Imperial_Sizes/c120_126/p29050/Aluminium_Flat_Bar_-_Imperial_Sizes_(6082T6)_12_in_x_1/2_in/product_info.html

jcb121
01-08-2011, 01:36 PM
I genuinely didn't realize that they had more then 1 page. I thought their biggist was 20x40! I didn't even bother looking for page numbers!

I can get away with using 6"x3/8"x... it's 15 for 1000mm so it should be more then enough. any metal above this size gets very expensive very fast!

I'm going to have to file the supports for the rail to allow the screw supports to be placed. I can live with that.

Jonathan
01-08-2011, 01:42 PM
Box/rectangular section would be stronger if you can find a bit the right size.

I think Chip used the 6"x1/2" for his gantry ... it was definitely something close to that.

jcb121
01-08-2011, 01:57 PM
The 6 Inch stuff will be 10mm to thin. it's either get something 10mm wider or knock 40mm off my cutting area!

Jonathan
01-08-2011, 02:07 PM
That's annoying as the next size up is 10" then 12"... if you decide to get the bigger size which has to be in a 2m length (I phoned them and they said they don't sell smaller) I might buy the spare from you. For a good price :lol:.

jcb121
01-08-2011, 02:11 PM
the only way I could make it work with 6" would be to mount the supported rails on the very edge of the alu and filed down the screw supports.

I'm talking 1mm from the edge of the hole to the side of the alu.

If i went for 10" it would be silly as my Z axis would be so wide it would be worse then using the 6" with the rails mounted properly!

John S
01-08-2011, 02:14 PM
Can you drop down to 6" x 3/8"?
A lot more cost effective.

http://www.aluminiumwarehouse.co.uk/Aluminium-Flat_Bar_-_Imperial_Sizes/c120_126/p17140/Aluminium_Flat_Bar_-_Imperial_Sizes_%286082T6%29_6_in_x_3/8_in/product_info.html

Jonathan
01-08-2011, 02:20 PM
Can you drop down to 6" x 3/8"?
A lot more cost effective.

http://www.aluminiumwarehouse.co.uk/Aluminium-Flat_Bar_-_Imperial_Sizes/c120_126/p17140/Aluminium_Flat_Bar_-_Imperial_Sizes_%286082T6%29_6_in_x_3/8_in/product_info.html

Somebody's not been reading the thread again :whistling:... he said that in post #11

Get the 10" and cut it? Or maybe get it delivered to me, I'll cut the edge off on my router and keep the offcut as payment...

jcb121
01-08-2011, 02:31 PM
This is wgat I'm talking about:

jcb121
01-08-2011, 02:47 PM
PCPPS v3.0

I was planning on getting the 4 axis one from Zapp but he was out of stock. I'm sure this one will do just as well. I'll be using DIYCNC drivers as well.

jcb121
01-08-2011, 03:45 PM
how is this for Z and y?

no snide remarks about it floating! :)

I'm not sure on the exact spindle size so it is mainly guess work :(

John S
01-08-2011, 07:26 PM
Somebody's not been reading the thread again :whistling:... he said that in post #11

..


That's me not reading page number this time :D

Jonathan
01-08-2011, 09:49 PM
how is this for Z and y?

I think you should go for the wider aluminium. It's annoying, but it won't hurt to have the Z axis a bit wider/stronger. It looks like you're using the same aluminium for Z... I'd make it stronger by putting the linear rails on the bit that moves up and down and the bearing blocks on the piece fixed to the gantry. That also saves a bit of aluminium/weight.

The stepper motor mounts have poor torsional stiffness...I'd either use bigger bar or plate or something.

Looks suspiciously like my spindle mount in the drawing :)


no snide remarks about it floating! :)

Wingardium leviosa.

jcb121
01-08-2011, 10:05 PM
it was your spinde mount, I tweaked it a bit.

The steppers will be mounted properly, that is just there for show as I cba drawing a Mount.

I'll give a go Jon, but I'm destroyed at the moment.

I got a new Motorbike today, I was so excited I couldn't sleep last night. so I didn't.

I'll to the metal shop tomorrow and see if they can do me a deal on some properly sized alu.

luke11cnc
01-08-2011, 10:26 PM
good luck JCB

on the deal that is :)

James

jcb121
02-08-2011, 05:38 PM
I've found some 180x12x80cm for 20.

not an excellent price compared to alu wharehouse but i'm not going to pay shipping so it's worth it.

luke11cnc
04-08-2011, 05:31 PM
Jcb

how is your build going have you made your bed yet (I sound like your mother LOL)

James

jcb121
04-08-2011, 06:14 PM
Jcb

how is your build going have you made your bed yet (I sound like your mother LOL)

James

it's going ok, My mother bought me a new 125 on monday. It's an RG125 1994, by tuesday, it's broken.

so I have to split the engine, new gaskets and seals etc.

I'm going on holiday on the 13th and I'm waiting for my stuff from my man in japan (I wish japan!)

I'll probably start after my two week holdiday in newquay :)

blackburn mark
04-08-2011, 08:42 PM
it's going ok, My mother bought me a new 125 on monday. It's an RG125 1994, by tuesday, it's broken.

so I have to split the engine, new gaskets and seals etc.

owch! i bet you were ringing its neck in first gear... buy some extra seals and rings... it'll need doing again by wednesday :rofl:

jcb121
04-08-2011, 08:54 PM
owch! i bet you were ringing its neck in first gear... buy some extra seals and rings... it'll need doing again by wednesday :rofl:

I had to but i didn't in first! there was no power in the bike at all! if anything they were riding it with popped seals.

I also discovered that the piston hit one of the powervalves! so they are screwed and they cost 130 each!

blackburn mark
04-08-2011, 09:42 PM
[QUOTE=jcb121;23237]I had to but i didn't in first! there was no power in the bike at all! if anything they were riding it with popped seals.
QUOTE]
allways a risk when buying a second hand two stoke... especialy an RG:naughty:

130!!! times have changed :confused: highly strung two strokes are murder for self distructing in first and second... i managed to melt an RD400 three times in the space of 500 miles(way back in the day when pistons and rings where cheap and power valves hadnt been invented)
if you let the motor reach its rev limit in first and second (ish) because of the low speed ergo low wind resistance and drag, the whole drive train goes slack and im pretty sure any lash in the motor causes enough vibration for the piston skirts start slapping against the liners, a bit chips off the skirt causing an imbalance causing more slapping and it quickly cascades into a disaster

over reving is much less important at 30mph (ish) and above as the wind resistance keeps the drive train nice and taught

jcb121
04-08-2011, 10:10 PM
grr it has to be done this week!

i need to ride to my MOD 1 on monday.

blackburn mark
05-08-2011, 12:32 AM
grr it has to be done this week!

i need to ride to my MOD 1 on monday.

i just did a bit of research on the powervalve (i never got my hands dirty on one) if the bike was a bit guttless after 9000rpm (start of the powerband) then the chances are the powervalve wasnt working in the first place... some versions aparently wear out and can drop parts into your cylinder, possibly what happend to yours ?

if you have all the other replacement parts it may well run well enough for your mod 1 without the powervalve running (i think you can assume it wasnt running anyway)
good luck man :sad:

jcb121
05-08-2011, 12:47 AM
Mate, you are almost spot on!

It was gutless all the time! I barely had the power to move me from stopped, I would have to clutch in and rev it again 2-3 times.

The power valve was working, I saw the servo moving about.

when I took apart the engine, the piston was worn to a smooth edge on one section. The power valve has fallen into the engine and it closed off half of the exhaust completely, as well as that the bottom end is leaking pressure.

this would explain how crap it was riding!

The powervalve hasn't completely fallen out of place though, i can still move it physically up and down with out issue. the power valve is in 3 sections and I think just the middle one has fallen down. this would also explain the rattle I heard when riding and the worn piston.

TheTuningWorks have a set of two blades for 250 that i will be buying tomorrow with weekend delivery.

I need to find some good liquid gasket though, the manual states suzuki bond 1215 but I can't find this stuff anywhere and it's a bit late now!

blackburn mark
05-08-2011, 01:08 AM
I need to find some good liquid gasket though, the manual states suzuki bond 1215 but I can't find this stuff anywhere and it's a bit late now!

might be worth bending some ears in a local bike shop,,,, not the pocket rocket supermarket type where the staff dont know what oily hands look like and would love to sell you some super duper suzuki bond 1215 for 60
id be looking for some ugly bugger with a beard and oil tattood into his hands... im sure he will have a nice equivelant in a dusty box for a tenner :)

m_c
05-08-2011, 01:37 AM
I'm guessing you'll be needing a sealant that's flexible and actually sticks things together (not like the usual silicon gasket stuff, which doesn't really glue anything together, just fills holes).

Genuine Ford and Vauxhall sealant are good, and reasonably cheap (Ford stuff comes in a handy little dispenser tube, whereas Vauxhall comes in a short mastic tube and needs a mastic gun). Failing that, Tigerseal is always good, but may make future dismantling a bit more challenging!

blackburn mark
05-08-2011, 01:52 AM
Tigerseal is always good, but may make future dismantling a bit more challenging!


that sounds like the type of stuff :smile: ..... you wouldnt happen to have a beard and tatto's on yer face would you M_C ?:smile:

jcb121
05-08-2011, 01:55 AM
I don't have a problem with dismantling it! I have all the tools needed to split them.

I genuinely couldn't get the cylinder off though.

on my 2nd day of riding the bike, I went to my metal shop to price up some alu for my cnc, went there today and said it was broken. he genuinely looked sad and gave me some steel and bolts for free.

he just told me to get the bike running!

I drilled holes for the cylinder studds in the metal and drilled a central hole. I had a 100mm bolt to push down on the piston and pull up the cylinder.

marked the piston badly but it was scrap anyway.

thinking about it, i should have picked up some alu at the same time and started to build my CNC on the cheap!

Sticky is ok, It has to be strong mainly. it needs to withstand oil, coolant and high pressures from the bottom end.

m_c
05-08-2011, 02:12 AM
that sounds like the type of stuff :smile: ..... you wouldnt happen to have a beard and tatto's on yer face would you M_C ?:smile:

Tigerseal is just a brand name for PU (Polyurethane) adhesive, and is used in the motor industry for sealing/sticking car panels on. It relies on moisture to set, and once set nothing other than physically cutting it of will shift it. Just make sure you wear gloves when dealing with it, as if you let it set on your skin, it takes a good few days for it to eventually fall off.

And no tat's here, only stubble!
Although I am known as the grumpy one at work...

jcb121
05-08-2011, 02:23 AM
I don't think i'll need anything that extreme!

blackburn mark
05-08-2011, 02:30 AM
I don't think i'll need anything that extreme!

hahahaha! i was thinking that.... im going to store that one in my memory though, Polyurethane adhesive.... might come in handy

m_c
05-08-2011, 01:21 PM
PU does come in handy, but a proper instant gasket is what will be needed.
I'm not sure what you can get aftermarket that isn't just overpriced black silicon, hence my suggestion of either the Ford or VX stuff.

jcb121
08-08-2011, 12:40 AM
So, I will have all my CNC stuff my this Week.

Only problem is, due to this motorbike mess, I have no money for the frame!

And I'm going on holiday next week so no building for atleast 3-4 weeks! :(

Peter.
08-08-2011, 01:05 PM
Threebond 1194 is what you want. It's the replacement of the product that used to be sold as yamabond/suzukibond (has no lead in it now). Comes in a tube for about 22, apply it with a small brush so it goes on thin. Before you join the cases make sure there are no raised edges from prybar bodgery to hold the case halves apart, as air leaks spell death for 2-strokes.

The powervalve isn't essential to the running of the bike, in fact some bikes were sold with the valve present but no actuator - the valve was fixed in a pre-set location (the TZR125 was not sold with the actuator as a uk bike in fact). If your piston was damaged then that would be the cause of the very poor power at low revs, the valve just alters the port timing to provide increased drivability down low and high throughput at revs. If you had no valve, you would suffer from poor low down response but not to the level you are describing. Bottom line is - you don't need one for getting about.

jcb121
08-08-2011, 11:02 PM
Threebond 1194 is what you want. It's the replacement of the product that used to be sold as yamabond/suzukibond (has no lead in it now). Comes in a tube for about 22, apply it with a small brush so it goes on thin. Before you join the cases make sure there are no raised edges from prybar bodgery to hold the case halves apart, as air leaks spell death for 2-strokes.

Thank you, there is 100grams for 10 on the fleabay so will have to buy that!

jcb121
09-08-2011, 10:24 PM
So, Not really an update but finally got my electronics sorted :D

4330

and I think I hit my Aim of it being cheap-ish.

all of it for just under 180 quid, still 170 too much though!! :heehee:

My other bits should be here Friday :D

jcb121
11-08-2011, 12:05 AM
Has finally got all my stuff!

4335

Why do i have to go on holiday now!!

I also picked up some 1104 three bond instead of the 1194,

1194 is safer to use as it doesn't use Lead. but i thought, I ride a 2t, I'll live on the edge for a bit :P

Now, all I need is some electrical wire, a Crap load of Aluminium and I'll be done.

I really need some spindle mounts, Nema 23 Mounts and Ball screw mounts though......

Jonathan
11-08-2011, 12:08 AM
I really need some spindle mounts, Nema 23 Mounts and Ball screw mounts though......

Sounds like a job for me :whistling: Have you seen the ones of all those I've posted recently?

luke11cnc
11-08-2011, 12:11 AM
jess
only one ball screw on your x-axis??

James

jcb121
11-08-2011, 12:15 AM
yes, I have a sliding Bed design so I only need one, not only that, but the entire cnc will be more rigid and make things better,

Jess.

Jonathan
11-08-2011, 12:26 AM
yes, I have a sliding Bed design so I only need one, not only that, but the entire cnc will be more rigid and make things better,

A sliding bed does not mean you only need one ballscrew to drive it. When the cutter is at either limit of the Y-axis travel and cutting parallel to the X-axis the cutting force will create a significant torque on the bed causing it to deflect. How much it deflects depends on the spacing of the bearings supporting the bed, the distance between them and of course the cutting force. Two ballscrews completely eliminates this problem. It's like trying to go round a corner fast in a Reliant Robin...it does work but not as well.

jcb121
03-09-2011, 12:03 AM
I'm ordering a cheap mouse and a Serial cable today.

what sort of cables do I need for hooking up the breakout board, PSU and Drivers etc?

Jonathan
03-09-2011, 12:29 AM
I'm ordering a cheap mouse and a Serial cable today.

Mice are handy, but what's the serial cable for? Did you mean parallel?


what sort of cables do I need for hooking up the breakout board, PSU and Drivers etc?

For the PSU to driver you'll want something that'll conduct the required current without a big voltage drop. Probably 1.5mm^2. Some people use shielded...I don't think it's required in most cases.
For the breakout board to drivers standard 7/0.2 wire is fine (or anything you have lying around) as it's only a signal.
Drivers to steppers generally CY 4-core (which is shielded), 1.5mm^2. You need minimum 1mm^2 from the VFD to spindle, so the same as you use for the steppers will be fine.

jcb121
03-09-2011, 12:41 AM
maplins it is then.

parallel, yes I did mean that!

Thanks.

Jonathan
03-09-2011, 12:51 AM
maplins it is then.

Noooooooooooooooo.... they charge silly money and probably wont have the cable for steppers anyway. eBay/Rapid electronics/Farnell is your friend. I've got plenty of 7/0.2 wire (all the colours) and possibly the rest depending on how much you need?

jcb121
03-09-2011, 12:55 AM
Thanks John, I may just take you up on that!

Shouldn't need too much. I was just thinking about testing my electronic bits as I'm not even sure they work! I hope they do....

when putting them in the machine I'll order the cables.

luke11cnc
14-09-2011, 08:34 PM
Jess
How are you and how is that build going

I know you've had your problems but thats no excuse for no input or even saying hello

James

jcb121
15-09-2011, 06:16 PM
good timing on this post as I actually have an update!

I went to FromStock today and picked up a fair bit of ALU for my machine. all cut to size.

I'll get a pic of it when i find a camera.

I have enough to make my spindle mounts, and my gantry, the only alu i need now is some 50x10 and 50x20 for the frame.

jcb121
15-09-2011, 06:25 PM
4538

this is my fair bit of Alu, that's a 50cm ruler next to it and I got it for a stupid price.

it would be unfair to tell you the price due to pure jealousy, but you can guess at it :)

it's all 12mm thick also.

I will be drilling some holes later, but I need an engineers square to be really accurate.

45394540

Jonathan
15-09-2011, 07:00 PM
this is my fair bit of Alu, that's a 50cm ruler next to it and I got it for a stupid price.


So if the ruler was a stupid price how much was the aluminium? Looks like about 31 worth to me...so I guess a stupid price would be 20.

You seem to have laid it out with the Z-axis rails mounted to the Y-axis slide, not the other way round. Was that just for the photo? Putting the rails on the Z-axis so they move up and down and the bearing blocks are fixed is stronger.

jcb121
15-09-2011, 07:03 PM
the ruler was 1.29, 20 is bang on.

I'll give it ago with the rails the other way around, it's just I thought the extra weight would be a problem.

jcb121
15-09-2011, 07:06 PM
Jon, your awesome.

that's two birds with one stone right there.

the piece of alu I bought for the gantry was too thin by a few MM, mounting it the other way means it can work.

luke11cnc
16-09-2011, 07:43 AM
Jess
Have you made your frame yet??

I like the ruler

20.00 is a good price did you just name your price or give him the twenty and run lol??

well done where or who is going to cut your aluminium ??

James

My 6"x1/2" was 48.00 for 2 meters
and 12x3/4 was 143.00 for 2 meters

jcb121
16-09-2011, 09:52 AM
ha! well I haven't actually paid yet... so I named my price then ran!!

The Alu is pretty much all to size, The only parts that need cutting are the two small bits that are the spindle holder.

If i do need to cut some of the Alu, I can take it back to the metal shop and they will cut it for me for free.

I don't have a frame yet, I'll be going back to the shop to get some alu for it or getting it from aluwharehouse.

I might take some of the Alu into college with me today and drill it out on their Mill. just to make sure it's nice and accurate.

jcb121
17-09-2011, 03:18 AM
So, After an Hour or two of wiring everything up, It comes to defcon one.

I get my Old pc from the Man shed, install the windows drivers and Mach3.

Clean my desk (move everything from my desk onto my bed)

Hook up the power and then.......


I go to plug in the Parallel cable and it's a Male instead of a Female connector!!

:redface: I never thought to check what type of parallel cable I needed :sad:

Rogue
17-09-2011, 01:01 PM
Ouch. Yeah I've had the same problem with serial cables in the past. You can pick up genderbenders fairly cheaply but to be honest, might just be easier to buy a new cable.

jcb121
17-09-2011, 09:38 PM
So, I've ordered a Gender bender for my cable so I should be able to test all the electronics.

I've got some Micro switches from an arcade cabinet I made ages ago, so I'm going to try and make some limit switches also.

my thought are, how am I going to make everything accurate enough by hand? I have recently bought a square ( something my college amazingly lacked) and I plan to mill the ends of me metal by hand so they are perfectly square,

but are there any tips for getting everything bang on?

The tools i have to get this together are a square, small drill press, auto punch and a rule so getting this thing together will be my biggest challenge.

jcb121
19-09-2011, 07:01 PM
Pictures!
45814582458345844585458645874588458945914590

I've milled most of the big blocks of alu in college so the edges are straight.

Just need to start mounting everything and it will soon be done :D

The Mill in college is complete crap, there is a MM of backlash on the X axis! really screws up my work :(

The Y is ok though.

Some of I2I's masterclass machining above.

Jonathan
19-09-2011, 07:35 PM
Looks like a good start :)


The Mill in college is complete crap, there is a MM of backlash on the X axis! really screws up my work :(

1mm of backlash is mildly annoying, but it really doesn't affect the results when using manual milling machine. Unless of course you're not compensating for it / locking the slides if necessary?

m_c
19-09-2011, 07:50 PM
Looking good.


Pictures!
The Mill in college is complete crap, there is a MM of backlash on the X axis! really screws up my work :(


Only a poor workman blames their tools ;-)
Every one of my manual machines has play, it's just a case of learning how to deal with it!

jcb121
19-09-2011, 07:53 PM
you can lock the slides? D:

annoying when you are on your 3rd attempt of work and the line you are doing suddenly turns into a nobly line.

Jonathan
19-09-2011, 07:55 PM
m_c ... looks like we're of the same mind - our last posts are virtually identical!

My mill has about 0.45mm backlash on X and 0.3mm on Y and it's no problem when using the machine manually. You just make sure to if it's a bigish cut lock the slide that your not moving, and when you move that slide to the required position compensate for the backlash by approaching the point in the same direction. You will also generally want to use conventional, not climb, milling.


you can lock the slides? D:

annoying when you are on your 3rd attempt of work and the line you are doing suddenly turns into a nobly line.

Look for some thumbscrews that apply pressure to the gib strips to lock it. Don't move the other screws on the gib strips ...

m_c
19-09-2011, 07:56 PM
Also ramp milling is essential when dealing with large amounts of backlash.

jcb121
23-09-2011, 04:42 PM
4633

now just another two to do! fun times.

I had to borrow a tap holder from school,

I2I, the tap holder I had wouldn't even tighten on an M6 tap!

jcb121
24-09-2011, 08:51 PM
So, mounted my rails on my bit of alu, also mounted the screw as well

463546364637

the ballscrew isn't perfectly central, off by 3mm or so.

but it's going pretty well.

jcb121
07-12-2011, 05:14 PM
Holy Batman what's this? an epic thread Resurrection?

Yes, I abandoned all hope of making a CNC machine myself. My equipment just isn't accurate enough for my perfectionism.

So, I've dropped in the big guns.

The frame of my CNC is being Water cut, I have just paid for it, so it should be coming X-mas time.

I think if it comes X-mas eve I may wrap it up and give it to myself as:

1. I'm not getting many presents this year

2. See above,

So hopefully there will be an update here soon! and a proper one, Not like this.

Merry Xmas all.

luke11cnc
07-12-2011, 05:49 PM
good because I was going to send you a email:tongue: asking to buy it off you cheap:rofl:

Have a good Christmas


James

jcb121
05-01-2012, 07:57 PM
Ok, Finally got my stuff from the water Cutters and it's PERFECT!!

http://i1187.photobucket.com/albums/z384/jcb121/CNC/IMG_0126.jpg
http://i1187.photobucket.com/albums/z384/jcb121/CNC/IMG_0128.jpg
http://i1187.photobucket.com/albums/z384/jcb121/CNC/IMG_0129.jpg
http://i1187.photobucket.com/albums/z384/jcb121/CNC/IMG_0135.jpg
http://i1187.photobucket.com/albums/z384/jcb121/CNC/IMG_0143.jpg

The frame is just resting together ATM, need to get two M6 nuts and mount the rails properly. The ball Screws should be in there tomorrow and the electronic sorted out over the weekend.

From a pile of metal to the photos above took about 30 minutes! so nice and quick :D

The company that did the water cutting was called Yorkshire Profiles.

luke11cnc
06-01-2012, 09:30 AM
Yes jess

that looks really nice mate I wish you good progress for the weekend I'm looking forward to seeing it finished

James

m.marino
06-01-2012, 04:39 PM
Well done. Good to see it coming together and best of luck with the rest of it.

Michael.

jcb121
10-01-2012, 02:59 PM
Ok, So i've mounted most of the bits, all I'm missing now are the stepper holders and the spindle mounts.

Also, What kind of wiring do I need? This will be used for my Steppers, Spindle to VFD, and generally all the wiring.

Thanks, Pics soon.

Jonathan
10-01-2012, 03:42 PM
Looks good, except for one thing. You have put the rails for the Z-axis on the Y carriage. It's much stronger if you have the bearing blocks for the Z-axis on that carriage (in addition to the bearings for Y). I mentioned it in post #23 and #60. Although having said that with the way you've orientated it it wont make too much difference.

If you don't mind me asking, how much did it cost to get those bits cut?


Also, What kind of wiring do I need? This will be used for my Steppers, Spindle to VFD, and generally all the wiring.

Erm, post #53. Same wire for steppers and spindle to VFD.

m.marino
10-01-2012, 03:45 PM
What Steepers are you using? Shielded CY or SY wire is my best suggestion, as it really helps with reducing signal noise along the wiring.

Michael

Jonathan
10-01-2012, 03:50 PM
What Steepers are you using?

3 Nm, Nema 24 according to post #46 (well, the picture).

Since it's quite a small machine the cable length wont be too great, so 1mm^2 should be fine. Same is fine for the VFD-spindle.

jcb121
10-01-2012, 07:53 PM
Looks good, except for one thing. You have put the rails for the Z-axis on the Y carriage. It's much stronger if you have the bearing blocks for the Z-axis on that carriage (in addition to the bearings for Y). I mentioned it in post #23 and #60. Although having said that with the way you've orientated it it wont make too much difference.

If you don't mind me asking, how much did it cost to get those bits cut?



Erm, post #53. Same wire for steppers and spindle to VFD.

Cost around 325 for the Aluminium and to get it cut perfectly, there are cheaper places but I was inpatient.

Mounting the rails behind the spindle plate in my Eyes isn't correct.
I don't know why it would be stronger and on our scale machines it may make no difference at all but I just prefer it that way.

5199

I know this drawing is unfair but I'm provin a point here.

Also, Once apon a time, my college used to be the place people went for engineering apprentiships, While all the CNCs and most of the lathes are gone now. I managed to find about 40 brand new end mill bits in the sizes 6mm and 4mm. These fit perfectly into my Spindle and my tutors said i could have them :)

And I'm going to buy a reel of single core wire between 1mm^2 and just use it for everything. I would go multicore for the steppers and drivers but I don't need a reel of it costing nearly 100 from Farnell and don't know where else to get cable.

Jonathan
10-01-2012, 08:21 PM
Mounting the rails behind the spindle plate in my Eyes isn't correct.
I don't know why it would be stronger and on our scale machines it may make no difference at all but I just prefer it that way.

5199

I know this drawing is unfair but I'm provin a point here.

The scale doesn't mean it makes no difference, just a little less. With profile rails it would make a lot less difference as they are so much more rigid. Unless the Z-axis travel is very short it will make a difference.
The reason why is most people start by mounting them like this:
5201
So clearly there there is a large overhang = weak.

However you've mounted it like this:

5200

Which is better than the previous, as at the bottom of the travel (where you'll use it most for thin materials i.e. cutting aluminium for which it is the most rigid). However further up you're relying on er... the spindle for rigidity instead of with the configuration I suggest the aluminium plate and rails.

EDIT: Actually the second diagram is just the same as the first except instead of using aluminium plate to hold the spindle you're relying on the strength of the spindle itself.

Chip did it like in the first drawing and unfortunately found out the hard way when he tried to cut aluminium. I started by drawing the same on my Z-axis (400mm travel), but fortunately someone pointed it out so I changed it.

Jonathan
10-01-2012, 08:25 PM
Cost around 325 for the Aluminium and to get it cut perfectly, there are cheaper places but I was inpatient.

Rather you than me...I'd have cut it for less on my router but it would have taken longer.


And I'm going to buy a reel of single core wire between 1mm^2 and just use it for everything. I would go multicore for the steppers and drivers but I don't need a reel of it costing nearly 100 from Farnell and don't know where else to get cable.

What length do you need for all the motors and the VFD to spindle?

JAZZCNC
10-01-2012, 08:32 PM
And I'm going to buy a reel of single core wire between 1mm^2 and just use it for everything. I would go multicore for the steppers and drivers but I don't need a reel of it costing nearly 100 from Farnell and don't know where else to get cable.

Here you go http://www.csecables.com/control-cable/control-cable.asp buy just what you need.

Edit: Better link http://www.csecables.com/acatalog/Flexible-Control-Cable.html




Mounting the rails behind the spindle plate in my Eyes isn't correct.

Well you need to go to Spec savers then. .:lol: . . Look closer and you'll figure out why.!! . . . It's quite obvious if you think about levers and lever length's.:question:

The rails mounted on the front plate make a big difference when it come to reducing chatter.!

Jonathan
10-01-2012, 09:09 PM
Here you go http://www.csecables.com/control-cable/control-cable.asp buy just what you need.

Edit: Better link http://www.csecables.com/acatalog/Flexible-Control-Cable.html

I just thought 'it's gone down in price since I bought the 100m reel', then I tried pretending to buy 10m of 1.5mm^2 and they want 9.50+vat for postage...extortionate!! That makes it 2.21 per meter for 10m.

Let me know how much you need as I'm happy to sell some of mine.

JAZZCNC
10-01-2012, 09:33 PM
I just thought 'it's gone down in price since I bought the 100m reel', then I tried pretending to buy 10m of 1.5mm^2 and they want 9.50+vat for postage...extortionate!! That makes it 2.21 per meter for 10m.


You can do what I do and tell them you're sending in your own courier, parcel to go about 4.50. . . . . Anyway how much do you think it would be to send heavy cabel via the post office.?

Jonathan
10-01-2012, 09:44 PM
You can do what I do and tell them you're sending in your own courier, parcel to go about 4.50. . . . . Anyway how much do you think it would be to send heavy cabel via the post office.?

They let you do that? I often say that to eBay sellers, didn't occur to me to try it on a proper company.
It's about 120 grams per meter, so can probably get 8m in 1kg for 3.15 2nd class. Or standard parcels is 4.41 for 2kg ... parcels2go probably less as they keep spamming me with emails about how cheap they are.

JAZZCNC
10-01-2012, 11:31 PM
They let you do that? I often say that to eBay sellers, didn't occur to me to try it on a proper company.


Yep it's just the same as collecting in person. Only your getting someone else to collect for you.!

I find P2GO ok thou I very rarely send light stuff or have it collected.

motoxy
11-01-2012, 06:09 AM
Jonathan. quite often good courier deals on ebay. Not been let down yet.

jcb121
18-01-2012, 11:19 PM
So, Even though I have steppers, I'm going to upgrade them to something a bit more powerful. 4.2Amp Steppers (http://www.ebay.co.uk/itm/170562167683?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3083wt_905)

But, How do I power this? I could get a 600watt (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=120845145621#ht_500wt_965) power supply or I could get a transformer from Farnell and risk blowing myself up.

Just wondering the best way to power it, I'm guessing a few of you guys have them.

so how have you guys done it?

JAZZCNC
19-01-2012, 12:38 AM
So, Even though I have steppers, I'm going to upgrade them to something a bit more powerful. 4.2Amp Steppers (http://www.ebay.co.uk/itm/170562167683?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_3083wt_905)

But, How do I power this? I could get a 600watt (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=120845145621#ht_500wt_965) power supply or I could get a transformer from Farnell and risk blowing myself up.

Just wondering the best way to power it, I'm guessing a few of you guys have them.

so how have you guys done it?

Build your own it's not hard, just need toroidal transformer, capacitors and bridge rectifier. . . there also prefered because Unregulated supplys are simple and more forgiving regards back EMF.
Steppers when decelerating from high speeds can become alternators sending power back into the drives which gets passed back to the supply. Linear regulated type supplys struggle to handle this and can tripout because often they have protection circuits. Where as unregulated supply's just absorb most of it in there filter caps.

Usually works out a bit cheaper as well if you want high volts & amps.

How many volts & Amps are you looking for.?

Lee Roberts
19-01-2012, 02:25 AM
You could try Philip Lambert over at http://www.metallin.co.uk/shop/ as well he may be able to help.

jcb121
19-01-2012, 05:46 PM
So the steppers run at 50v and 4.2A. so i will need something that can output 50v at 12.6 Amps. Multiply those to together, so I need over 630 watts/VA? A lot of the transformers I've seen run off 230v instead of 240v,

would this be ok?
http://www.rapidonline.com/Electrical-Power/Toroidal-Transformer-800va-0-50v-0-50v-88-3848

I know hardly anything about electronics,

or could I use one of these http://www.rapidonline.com/Electrical-Power/Toroidal-Transformer-625va-0-50v-0-50v-88-3844 and run the steppers at 4A. :S

Is there a circuit diagram I can base this PSU on?

Jonathan
19-01-2012, 07:07 PM
So the steppers run at 50v and 4.2A. so i will need something that can output 50v at 12.6 Amps. Multiply those to together, so I need over 630 watts/VA?

The steppers run on 50V, but a transformer rated for 50V is 50V rms and you're rectifying the output and storing in a capacitor so the output voltage is actually close to the peak voltage, i.e. 50*2^0.5=70.7V. In reality you get a bit less than that due to the forward voltage of the diodes and numerous other factors. This means you can actually use no greater than 50/2^0.5=35.4V. A 36V (or one with two 18V secondariness placed in series) might be fine, but really it's too close to the limit so from Rapid the nearest is 30V, 88-3838 (http://www.rapidonline.com/Electrical-Power/Toroidal-Transformer-500va-0-30v-0-30v-88-3838). 32V (or 16+16) would be good too.

Next consideration is the current. For 3 motor a 500VA (or greater) transformer will be fine as it's actually a lot less current than you'd intitially expect. I recently tested with the same motor on 48V and the maximum continuous current (with the motor at full power) was just over 1 amp. You need more than that in reality for the peaks, hence 500VA is fine.


A lot of the transformers I've seen run off 230v instead of 240v,

Don't worry about the difference between 230v and 240v - it's insignificant as the 10% tolerance on the UK mains voltage encompasses that range. Often the transformers have two primary windings so you can put them in series to get 230V or in parallel for operation from 115V.

The circuit is widely available. Just the transformer, a bridge rectifier and electrolytic capacitor. For example:

http://www.cnccookbook.com/img/LatheStuff/CNCConversion/StepperPowerSupplySchematic.jpg

jcb121
16-02-2012, 03:29 PM
http://www.youtube.com/watch?v=F-rnR6oeygE&feature=youtu.be

This Is progress so far, sorry I haven't been updating it too much.

Big thanks to John S and I2I for helping me out.

All that is left to do is secure the Y motor, and attach the 20mm plate to the 10mm plate floor bit.


And get loads of screws.

motoxy
16-02-2012, 11:23 PM
Lots of success on the sites machines at the moment. Well done and looking good. (machine not you):lol:

bruce

jcb121
17-02-2012, 12:11 AM
Bugger,if you see the panel that holds the rails for the Y axis, the motor mount secures onto that on top. but it's a bugger to drill and I just screwed up it!So I'm going to need to get those two panels remade. the motor mount and the panel itself.I've drawn a drawring5365on the right is how I've done it, this means it's super difficult to drill the hole down properly as I have to do it with a cordless. on the left is how it should have been done and how it is done on my X axis.I will probably post up a RFQ post after this, but this really is a Pain. I was so close to finishing.

kylelnsn
19-02-2012, 08:55 PM
If you don't mind me asking what is your total build cost? And your estimated final build cost?

What is you're cut area?

jcb121
19-02-2012, 10:15 PM
Cutting Area is A3. with 100mm Z

Supported rails, ball screws, mounts, spindle, VFD, Bearing Blocks, Ball screw nuts, 530 incl P+P and Tax (http://www.ebay.co.uk/sch/linearmotionbearings2008/m.html)

Nema 23 motos: 81.60 (http://www.ebay.co.uk/itm/3-Stepper-Motor-3-1Nm-Nema23-439oz-1yr-Warranty-cnc-/110817268478?pt=UK_BOI_Industrial_Automation_Contr ol_ET&hash=item19cd3952fe#ht_500wt_1180)

Stepper Drivers: 45 (http://www.mycncuk.com/forums/showthread.php/3584-3-x-2-5Amp-30V-Stepper-Drivers)

Breakout board: 17.98 (http://www.diycnc.co.uk/html/pcpps.html)

Power Supply: 35

Aluminium and Water Cutting: (http://www.yorkshireprofiles.co.uk)331

Various screws from Screwfix 25

Pump and accesories 15

Steal Subframe and feet, 18

Can't think of what else of the top of my head. My budget was a grand that my Nan gave me.

Jonathan
20-02-2012, 11:24 AM
Even with those cheap drivers I would expect higher acceleration than you are currently using. Keep increasing the acceleration setting until either it stall or the machine shakes about too much, then back off a little to be safe. Aiming for something like 500-1000mm/s^2.

If you put a cable tie round each stepper motor that'll stop the plastic wire guard things snapping off.

jcb121
20-02-2012, 02:49 PM
All i have done in mach is set the step per mm to 40 and set a speed of 2mps. I haven't even messed around with anything else so I will be doing that when it's all together.

jcb121
03-04-2012, 08:29 PM
So, I've finally got it all together.

I turned on the power supply for the steppers, then the VFD, turned the spindle on and the entire machine shakes, the Spindle is making the Steppers step.

My guess is to move the pc as far away as possible? wrap everything in tin foil :P? I'm using SY Cabling.

luke11cnc
03-04-2012, 08:36 PM
Jes Have you got the wiring earthed ?? and the machine earthed ??

James

Jonathan
03-04-2012, 09:12 PM
Make sure the CY cable shielding is all earthed at just the driver end. Connect the earth wire from the VFD via the spindle wire to the spindle body/Z-axis. Also earth the machine frame.

JAZZCNC
03-04-2012, 09:16 PM
Things to check.

Check VFD Shield wires goto ground, VFD is one of the few execptions where it's ok and even recommended by some manufacturers to ground both ends of the sheild.
No signal wires, so steppers,estop etc run along side VFD cables or even along side any power cables.
Don't cable tie signal wires together or along side power wires.
Use a Star grounding in control box.
Double check all connections for lose wires, Esp the earth.

Does it only do it when spindle starts or when you actually turn the VFD on.?

jcb121
03-04-2012, 09:37 PM
only when the spindle starts to turn. I just took out all of the cabling and wired up just the Z axis in a different way, and It's working fine now :)

must have been a bad earth.

jcb121
03-04-2012, 10:18 PM
It's all working :D!!!

but it's too late to do anything :(

big thanks to 2e0poz (http://www.mycncuk.com/forums/member.php/815-2e0poz) and i2i (http://www.mycncuk.com/forums/member.php/1061-i2i), Couldn't have done it without you guys!

Jonathan
03-04-2012, 10:24 PM
but it's too late to do anything :(

Mine's currently running .. it's never too late!

Swarfing
04-04-2012, 02:37 AM
Good hear JCB :thumsup: