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pet30
19-06-2017, 08:10 PM
Hello

I am peter 30 from belguim.
first of all sorry about the bad english i don't typ it a lot.

I am thinking of building a cnc and i hope you can help me with the design.

The idea i have is a machine of about 3000x 1600.
Why this big ? because i have a small company and i make kitchens ,dressings,TV cabinets etc.
this way i can lay down a sheet of MDF of melamine and cut the pieces .

But the thing thats special about the machine is the next thing:
i want the gantry to be 3000 mm, so basicly a big gantry and smaller X axes then normal.
i was thinking for the gantry 160 mm high and 80 mm deep.
is this enough or do i need to make it bigger so it do's not flex?

Instead of linaire rails i was thinking a strip of steel or alu and then ball bearing rolling on the alu or steel rail.
the reason why is simple.
I want to start with a budget machine and later in the future upgrade it with better linaire rails like hiwin etc but for know i don't have the money to spend on expensive linaire rails.
for now i will use a bosch router but also in the future a spindle.

For the drive i was thinking rack&pinion module 1 is this enough or do i need to use 1.5 or 2?
the motors and R&P will be mounted on the rails on top.

i was thinking to use these motors.
Nema 23 stepping motor 57BYGH627

is this strong enough or not?


i made some drawings in sketchup.

Sorry for the many questions but i just want to be sure before i start building.

Robin Hewitt
20-06-2017, 10:08 AM
Your machine has so many mistakes I don't think your kitchens will fit together very well.

Have you considered copying someone else's working design and fixing their mistakes rather than inventing your own?

pet30
20-06-2017, 12:10 PM
what are the mistakes?

and do you reccomend someone else's design?

mekanik
20-06-2017, 02:34 PM
Hi pet30
Welcome to the forum
I can't see any logic in having your gantry that long the machine would normally have the gantry spanning the shortest width.
trying to construct a gantry that length you are on a hiding to nothing, have a look through some of the build logs.
Enjoy the forum.
Regards
Mike

hanermo2
20-06-2017, 02:53 PM
Forget the round rails and bearings.
I tried it circa 2006..

Steel frames, sand for smoothness / non-binding,
increase section sizes 2-5x,
glue in with industrial goops and bolt if you want, ..

For accuracy, a steel or granite machinists reference edge/plate, vertex 1000 mm is cheap to 0.04 mm / m,
sand with wide belt sander to remove most of the bend/curve.
Then assemble/build, with non-binding free-running linear guides.

You probably cannot make a good commercial-level cnc router for cheap --
no-one can.
Look at mechmate. 8-10k for parts.
I will likely make one for a local business for full-sheet 2.5 x 2 m size .. and will charge 20k or so.
It MUST have a toolchanger to be useful/profitable.
Likely, it will be horizontal, like the more productive modern CNC machining centers.

Most likely, the 20k cost is paid in 1-2 months.

pet30
20-06-2017, 03:01 PM
and if i was to change the gantry to 1600 mm so just flip the design?
could i then use ball bearings etc?

is not my fulltime job , i make kitchens etc after hours. so the machine do's not need to get super fast speeds.

and could i use the same system as this machine? he uses rack&pinion and round rails


http://www.rawcnc.com/

hanermo2
20-06-2017, 03:16 PM
Strength is not the issue.
Rigidity is.

All machine tools are loaded, at max, to == 2% of their strength ie yield point.
Machine tools today are lightly loaded stressed-skin structures.

You can make a router with the ball bearings, and it will work. Yes.

It will not be productive vs others, and cannot use modern carbide cutters, due to flex/vibration/chatter, effectively.
Your proposed solution will work fine at 5-10 ipm, feed, where real machines run 100-200-800 ipm.
So about 20x less productivity.

Ger21
21-06-2017, 02:58 AM
It will not be productive vs others, and cannot use modern carbide cutters, due to flex/vibration/chatter, effectively.
Your proposed solution will work fine at 5-10 ipm, feed,

This is 100% not true.
Do not listen to Hanermo, who tells everyone that they need to spend $20,000 on a 10,000 lb machine.
I built a machine 13 years ago, out of wood, using skate bearings on round pipe for the linear bearings. It still runs today, and I can cut at 200ipm, with carbide cutters. :triumphant: With better motors and drives, It could cut much faster.

Having said that, your design does have some serious flaws.

Not sure what material you plan on building from, but it looks like a simple aluminum tube?
If you want to use 80x160 for a gantry, it really needs to be a heavy extrusion, not just a tube. That tube you have modeled will easily flex and twist.

While skate bearings can be made to work, there are some things you need to be aware of.
They need to be in very tight contact with what they are riding on, in order to have a rigid structure. And on a flat surface like that, they are not very tolerant of dust and chips, and will bind if dust builds up under them.
You also are only showing bearings in one direction in each carriage. You need additional bearings to constrain the carriages in the other direction.

This is a very large machine. It's easy to build a fairly rigid small machine. But as the machine gets bigger, it gets much more difficult. Everything needs to be bigger and stronger, to achieve rigidity. And rigidity is of the utmost importance.
I think that you will be very disappointed if your first machine is this large. I would recommend building a much smaller machine, which will teach you where you need to improve your design. If you build something similar to what you've shown, it likely won't be worth upgrading in the future. Build a small, inexpensive machine to learn with, and a larger, more expensive machine when you can afford to.

You can not direct drive the pinion on the stepper shaft. you'll have poor resolution, and not enough power.

Desertboy
21-06-2017, 07:25 AM
Morning, do you have a budget in mind for this?

Boyan Silyavski
21-06-2017, 08:12 AM
Your idea is riduculous. Be realistic and prepare a budget of 6k for simple machine this size or better 8k for a Ferrari

Just copy my second machine and it will do whatever job you throw at it. No need for the heavy duty Z, just 3kw spindle. I have plans for it that i sell to people that know what they want and i offer one to one support for the build.

Tool changer is not needed for kitchen jobs and it costs 3k at least and you need a controller that could do the job.

20k machine will NOT pay for a month. You need to have factory and at least 10 people working for you for that to happen. But then you will not be looking at DIY machine, right.

Maybe a second hand machine around 10k is better for you and will start making money at day 1. You will need 1/2 year at least to build your machine, even if you have the detailed plans of my machine or any other. Its not a one day job. Most people here like what they do and its their hobby, side business or similar so they take their time. Even if i have all pieces i will need a month to build it.


That may answer all your questions. And yes, crappy machines not with proper linear bearings will make you pull your hair off and will be total waste of time and money. MONEY.

Greeny
21-06-2017, 10:34 AM
Hi Peter,

If you cannot stretch to linear rails at the moment, you might like to have a look at mechmate design.
http://www.mechmate.com
http://www.mechmate.com/forums/index.php
I'm not necessarily saying use the whole mechmate design as its a little dated, but it has a lot of features you describe in your initial post.
Lots of info for making roller bearing rails, rack and pinion, and other stuff

Personally I would always keep the gantry as short as possible. 3m will offer huge challenges.

Cheers

pet30
23-06-2017, 09:08 AM
Hi pet30
Welcome to the forum
I can't see any logic in having your gantry that long the machine would normally have the gantry spanning the shortest width.
trying to construct a gantry that length you are on a hiding to nothing, have a look through some of the build logs.
Enjoy the forum.
Regards
Mike

i need the gantry to be this way because my workshop( ist at my parents house) and if i go home then my mothers car is parked in the garage so i this way i can still have a cnc .

Desertboy
23-06-2017, 09:20 AM
i need the gantry to be this way because my workshop( ist at my parents house) and if i go home then my mothers car is parked in the garage so i this way i can still have a cnc .

3m's is just too long though and you will be creating yourself a world of trouble, there are plenty of machines out there with 3m gantries they are very very chunky and use serious slides the cost of the gantries are far beyond what most of us spend on our entire cnc machines.

If you build it like you suggest it will not work very well at all and you will spend a lot on a frame you can't use.

https://www.kickstarter.com/projects/1830738289/maslow-cnc-a-500-open-source-4-by-8-foot-cnc-machi

This seems like it might be more useful to you although I would never consider this suitable for real production (I thought it looked crap but mate thought it was ideal for a small workshop for occasional jobs.) It might be something that ticks your boxes given the lack of space and tight budget.

There is another choice you could make the gantry 1.5m's and mount the CNC so it folds to the wall when not in use you can get more space and only use when the cars is not there.

You probably don't want to cover your mum's car in sawdust anyway if you still want the cnc machine their in a months time ;)

pet30
23-06-2017, 09:31 AM
the beams are 160x80x5 mm steel
they will be perfectly flatten at a machine shop not far.
then i wanted to put a flat steel plate of 120x5 mm and on the 2 side beams so the bearings can ride on this.
on the bottem of the flat bar ther will be 2 bearing that are pushed against the flat bar with a spring so its really thight .

the steppermotors would be nema 23 directly to the rack ( the rack is bolted to the flat bar on its side) and behind the rack ther would be a bearing so the gear can't jump a way
what do you think or what should i change

i was also thinking of using the mechmate V groove rails etc instead of the ball bearings.

Davek0974
23-06-2017, 06:12 PM
what do you think or what should i change



Your issue is going to be that massive 3m gantry beam - even at 160x80x5 it will flex and twist like a bitch.

Then there is weight - that beam will weigh about 55kg before adding motors, spindle, guides, motion etc - two nema23's will not do unless you add some decent gear/belt reduction - this will be a slow machine, this size stuff is servo motor territory i feel.

To stop the beam sagging, you add triangulation - a support from end to end raised in the middle and joined with a strut, this will not stop twist though and all this will add weight, I would guess a working 3m beam gantry would weigh in at around 200kg or more - this is silly and would mean using Aluminium to build it.

I'm not bragging on you here - just trying to save your money, i've built some dodgy small machines in the past but nothing this big ;)

pet30
23-06-2017, 07:27 PM
no problem thanks for the help

i know this is not easy to build but i think ist the only way i can have a cnc in the garage.

if i was to change the machine 90 ( making the machine 3 meters long and the gantry 1600 mm long) could it work then?

what do you mean with :
you add triangulation - a support from end to end raised in the middle and joined with a strut, this will not stop twist?

and how hard will it drop and twist?
if the cnc is accurate to about 1 mm on the 3 meter then its ok i can live with that
i am using it for shelfholes( 5 mm holes like ikea cabinets) and making some MDF doors , some holes for blum hinges etc.

Davek0974
23-06-2017, 07:40 PM
Yes make the gantry 1600 and things get much much easier.

I think for a router you will still possibly need 2:1 reduction on the drives though if using rack/pinion, ball screws would be ideal but much more money.

Triangulation - draw a long thin box - this is your beam, now draw a triangle on top spanning end to end of the beam, from the apex draw a vertical line down to the beam. You now have a box with much more vertical rigidity, triangles are very strong when used right. The trouble is this will not stop twist - you will not stop twist with a single beam that long - it will need two parallel beams with the spindle/z axis mounted between them, this will be very sturdy but 2 x heavier - there is no free lunch here :)

I doubt you will achieve 1mm tolerance in the middle of a 3m beam, plus you have lift - when the cutter plunges into the wood, the beam will lift causing tapered cuts etc.

Big machines need lots of design i'm afraid, and lots of money to make them work.

Clive S
23-06-2017, 08:52 PM
if i was to change the machine 90 ( making the machine 3 meters long and the gantry 1600 mm long) could it work then?There are a few examples of machines built vertically. Dean (Jazzcnc) has made a few and Neil (njhussey) has done one as well.
Deans are built with the long axis horizontal and Neil has done it with the long axis vertical.

Boyan Silyavski
24-06-2017, 09:47 AM
Save some money and buy proper linear bearings, at least round supported. Which in fact are very cheap. What you want to do is like driving on the Autobahn 200km/h with this:

21991

Desertboy
24-06-2017, 10:11 AM
I have SBR25 and would recommend that as the minimum for the longest axis and it weighs a ton so I wouldn't want it on my gantry. I'm putting 1.5m 15mm Hiwin clones I got on ebay with 4 carriages for €120 delivered on my gantry to keep the weight down.

I like my supported rail it's lovely and smooth but it's no Hiwin.

Boyan Silyavski
24-06-2017, 10:44 AM
I have SBR25 and would recommend that as the minimum for the longest axis and it weighs a ton so I wouldn't want it on my gantry. I'm putting 1.5m 15mm Hiwin clones I got on ebay with 4 carriages for €120 delivered on my gantry to keep the weight down.

I like my supported rail it's lovely and smooth but it's no Hiwin.

Thats what i am talking. Its cheap, its not Hiwin but hey, its supported bearing. Thats what i call the real "budget solution". It will work much better than any V and skate bearings. And i have such small machine /V with skate bearing/ from the time when there were no cheap Chinese bearings or machines. And i am telling you this is one of the things in life that have frustrated me most. I dont wish that to anybody. It will go in the museum of Bad engineering

Davek0974
24-06-2017, 10:44 AM
Looking at the dimensions more, i can only repeat earlier comments - this is not a machine for what is called "plates and skates" motion - ball bearings running on steel plates. It works reasonably for small stuff - my first plasma cutter was plate & skate but it jammed a lot due to crud on the plates and it was only 650x650mm, over a length of 3000mm the motion will not track square or level.

This would be a big machine, heavy and expensive I feel, it will need to be if it is to do any sort of work at all. If it were me building big, I would be looking at ball screws, 25mm linear rails, 750W servo motors at least, and a heavy steel frame. I would not even go with the round supported rail at this size. Just my thoughts of course. :)

Desertboy
25-06-2017, 10:57 AM
Looking at the dimensions more, i can only repeat earlier comments - this is not a machine for what is called "plates and skates" motion - ball bearings running on steel plates. It works reasonably for small stuff - my first plasma cutter was plate & skate but it jammed a lot due to crud on the plates and it was only 650x650mm, over a length of 3000mm the motion will not track square or level.

This would be a big machine, heavy and expensive I feel, it will need to be if it is to do any sort of work at all. If it were me building big, I would be looking at ball screws, 25mm linear rails, 750W servo motors at least, and a heavy steel frame. I would not even go with the round supported rail at this size. Just my thoughts of course. :)

I'm planning an 8*4 machine next for wood only and I was going to use SBR25 and I'm sure it would be very nice but the price of HIWIN 25mm from cnc4you (About 50% more) means I'll just go with 25mm Hiwin on X&Y and 20mm for the Z.

I costed it at ~1500 delivered from cnc4you for
2*2.7m HIWIN
2*1.6m HIWIN
2 * 2005 2.6m ballscrews with fittings
1* 2005 1.6m ballscrew with fittings

but I think I would want to fit a minimum 2510 (Or 2520) ballscrew for the gantry and R&P for the long axis (So I can do a dual gantry, independent drive).

R&P gets a bad rap but I've seen some very accurate setups out there certainly on par with the C7 ballscrews I would buy and with ballscrew mapping I'm sure well within any tolerances I would ever need with such a machine.

Davek0974
25-06-2017, 12:23 PM
For your HiWin, look into AliExpress, guy called BST Automation, thats where i got mine from.

R&P can be done well and is good on long machines - to get good accuracy look to anti-backlash pinions, they are like two pinions with a spring twisting them apart so the tooth is under tension all the time.

To check what screw, look at the speed/whip rating, longer they go the thicker they need to be, you can also tension the screw to stop whip.

Boyan Silyavski
25-06-2017, 03:10 PM
Just as a side note - 20 size Hiwin for all axis is ok. No need for 25 size. Ball screws: 1605 for the Z, 1610 or faster for the X, 2510 or faster for the Y and A long ballscrews and rotating nut setup. I dont see a point for faster ball screws though than xx10 for a Do-ALL-Machine

pet30
26-06-2017, 07:20 AM
Very interesting

https://www.youtube.com/watch?v=fwbkWM0mWfs

what are your opinions for this type of linair rails? could i use them

my budget was about 2000€ but i think i will need a lot more.

Desertboy
26-06-2017, 07:52 AM
Very interesting

https://www.youtube.com/watch?v=fwbkWM0mWfs

what are your opinions for this type of linair rails? could i use them

my budget was about 2000€ but i think i will need a lot more.

Looks a lot better than makerslide but still not proper rail! If you want actual production you need to expand you budget

I think if you double the budget you could build a very decent machine
22002

Boyan Silyavski
26-06-2017, 10:31 PM
That rails could be good for a month, but will need constant tweaking later. Its a better solution than roller bearings or V rails but... I dont know how you value your time but when actually working, any hit and miss day will cost you hundreds of $$$ missed profits.

My opinion again is to buy used machine, some times people from forum sell good ones. or pay sb to do it for you and start making money from day 1. Yes i build my machine, but it was a do-all-extraordinary :joker: and if i have to buy similar i have to pay more than 20k for it so there was a reason for the wait. But for pure woodworking, i wouldn't think twice and buy even Chinese, so to start making money faster

pet30
27-06-2017, 08:08 AM
Bying a cnc here is stil 20.000 euro or its a old machine etc.
I will go for the supported rails not the bearings.

Now the problem is i still have that big gantry of 3000 mm

How would you guys make that gantry strong so it don't flex and twist?

if its really difficult then i have to turn the machine 90 so the gantry is 1600 mm .

Desertboy
27-06-2017, 08:21 AM
I'd extend the frame a little so the gantry can move out the way completely so you can remove the work piece then it's irrelevant which way the gantry is. If you mount the hiwin's and ballscrew on the sides you can enclose them enough that when you access the piece it's not an issue.

Go for 1.6m gantry NOT 3m simple any other choice is just nuts.

Boyan Silyavski
27-06-2017, 08:31 AM
if you make the gantry like my gantry/ look at my signature, second build/ it will work perfectly at 3m span.

BUT:

-you will need 3m straight edge, not 2m. So instead of 250euros you are looking at 500-600euros. And nope, you can not build a machine like that without straight edge that spans on top of the longer rails/ Y and A/

-it will weight 250kg. Thatch not a problem but you will need servo motors which are expensive even second hand


Basically you want to build a machine like that so you have smaller machine that could do bigger jobs. Thats the reason for that setup.

I dont understand why is the problem? You only have to load it from side, so just make that side rails lower than the working bed. Thats all.

pet30
27-06-2017, 09:16 AM
thats a good idea i would have never thought on raising the bed of the cnc

then i will go for a 1600 mm gantry i think this is the best and strongest .

a beam of 160x80x5 mm will not work then?

mayby it best to take your cnc gantry design then.

can u give me advice on witch steppermotors to use?

Boyan Silyavski
27-06-2017, 10:32 AM
thats a good idea i would have never thought on raising the bed of the cnc

then i will go for a 1600 mm gantry i think this is the best and strongest .

a beam of 160x80x5 mm will not work then?

mayby it best to take your cnc gantry design then.

can u give me advice on witch stepper motors to use?



A beam of 160x80x5mm will work with some minor reinforcing.

Make the drawing and then calculate the weight when you are sure thats the final design. Then come the motors.


I greatly recommend doing a machine similar to mine with the changes that Z is simpler, gantry is the beam you have. Reinforce gantry with some additional 60x60 which will serve you to mount the rails . Most of all leave one gantry side raised like mine and simply eliminate other bed side. Instead the rail is lower than table and gantry side is longer. But you will still have the stiffness from the other side.

Below is a quick mock up of what of am talking about. I am not trying to sell you something here, but if you dont have the time or knowledge i can redesign the already proven design to fit exactly what you need, and by doing so you will avoid many possible mistakes on the way. I will help you here for free also of course, but then you have to design all yourself from scratch. Which is a very satisfying experience, but expect much time in understanding all details of a machine.


22009 22010

pet30
27-06-2017, 08:39 PM
i made some modifications

the profiles are 80x80x 5 mm think,my metal shop not far from here has got a lot of them.

for the gantry:

a beam of 80x80 then 80 mm high pieces on the beam and again 80x80 beam
on the back of the gantry 80x80x160 mm pieces welded against de total gantry to make it more stronger and less abel to flex.

because i will use r&p i was thinking mouting it on the gantry on top.
then on the sides 1 stepper motor in the steel beam 80x80( to save more space) and 1 just hanging on the bottom against the rack ,
thats mounted against the 80x80 3 meter steel beam.
22014
22015
22013

What do i need to change
the router i will be using in the beginning a bosch router but in the future probably a spindle.
the bosch router ways about 5 kg.

mekanik
27-06-2017, 10:01 PM
You could do with modifying the rack mounting arrangement on the the high X axis, it's going to get clogged with debris if you have it as shown.
Regards
Mike

Davek0974
28-06-2017, 06:16 AM
Also make the point where the gantry supports join the rails wider and get the spindle centre central to the bed-rail bearing blocks.

Desertboy
28-06-2017, 08:35 PM
At this price
http://www.ebay.co.uk/itm/Pacer-Cnc-Router-3000-2k-3000x2000mm-Vacuum-Bed-/282539947837?hash=item41c8b1773d:g:7zkAAOSwi8VZTQv W

I'd consider buying this and importing it I think it'd cost ~1200 to Germany but it might be too big for you. I know someone who would moves this no probs if you'd be interested have to get a quote.

Needs work but seems a cheap way to get a decent 8*4 router

pet30
29-06-2017, 07:38 AM
At this price
http://www.ebay.co.uk/itm/Pacer-Cnc-Router-3000-2k-3000x2000mm-Vacuum-Bed-/282539947837?hash=item41c8b1773d:g:7zkAAOSwi8VZTQv W

I'd consider buying this and importing it I think it'd cost ~1200 to Germany but it might be too big for you. I know someone who would moves this no probs if you'd be interested have to get a quote.

Needs work but seems a cheap way to get a decent 8*4 router

No its to big ,

i have max 3000x1800 mm if i go 2000 mm then the car can't go in the garage.

should i make a metal frame for the cnc or can i make a wooden frame and bolt everything ?

Desertboy
29-06-2017, 08:01 AM
No its to big ,

i have max 3000x1800 mm if i go 2000 mm then the car can't go in the garage.

should i make a metal frame for the cnc or can i make a wooden frame and bolt everything ?

Metal frame, really wants to be steel at that size but if you do use T slot aluminium you need chunky profile and I would have it predrilled so it bolts together rather than T nuts. I'm certain you can make it fold to the wall for extra space (Although not the machine I linked to lol) It will cost a lot more to make it from aluminium rather than steel, I lack the confidence to weld a steel frame for a cnc so i would use a coach builders to make my frame.

Or maybe it's time for your mum to take up motorcycle riding ;)

Boyan Silyavski
29-06-2017, 09:39 AM
That used machine looks very promising.

Lee Roberts
29-06-2017, 11:22 AM
That used machine looks very promising.

I know its also so close to me i could reach out and touch it, would be prefect project for me.

Desertboy
29-06-2017, 11:25 AM
I know its also so close to me i could reach out and touch it, would be prefect project for me.

If I wasn't so skint right now I would be buying this today ;)

At prices like that it's not worth building an 8*4 I'd just buy one I have no doubt 1k and you can get that working and 2k and you can get working like new.

Clive S
29-06-2017, 11:35 AM
If I wasn't so skint right now I would be buying this today ;)

At prices like that it's not worth building an 8*4 I'd just buy one I have no doubt 1k and you can get that working and 2k and you can get working like new.

I don't think its 8x4 its 3mtr x 2mtr bed so probably bigger still.

Desertboy
29-06-2017, 11:39 AM
I don't think its 8x4 its 3mtr x 2mtr bed so probably bigger still.

I always think of these as 8*4 machines lol as that's what I mostly would use it for but the ability to do 10*5 would be very useful but only occasionally. If i do build my own I will build it to have a workspace of 3m*1.6m because you never know when you need those extra inches ;) Space is not an issue to me at the moment within reason I could fit 3 of these machines in ;)

This machine would be spot on for what I want, I would then convert what I'm building now into an aluminium machine for cutting molds for vac forming and use the big one for wood only.

pet30
29-06-2017, 12:43 PM
the frame could i make it out of 50x50x3 mm or do i need to use bigger and heaver steel?
i found this shop in holland i think the price is ok because i need supported rails of 3 meter long

https://www.hardware-cnc.nl/en/shop/lineair-guides-parts/supported-round-rail

Clive S
29-06-2017, 01:29 PM
the frame could i make it out of 50x50x3 mm or do i need to use bigger and heaver steel?
i found this shop in holland i think the price is ok because i need supported rails of 3 meter long

https://www.hardware-cnc.nl/en/shop/lineair-guides-parts/supported-round-rail

You need to draw this up in Cad otherwise you will waste a lot on money quickly. What do you mean by "the frame" its hard for people to advise you without the CAD drawing.

pet30
29-06-2017, 02:02 PM
with frame i mean the base of the machine,

i don't have cad program just sketchup i am a woodworker so for drawing kitchens etc thats good enough but i can draw very accurate in sketchup

Clive S
29-06-2017, 02:55 PM
with frame i mean the base of the machine,

i don't have cad program just sketchup i am a woodworker so for drawing kitchens etc thats good enough but i can draw very accurate in sketchup

At some point you will need CAD and CAM Fusion360 is good and free

Desertboy
29-06-2017, 03:14 PM
with frame i mean the base of the machine,

i don't have cad program just sketchup i am a woodworker so for drawing kitchens etc thats good enough but i can draw very accurate in sketchup

I know people love Fusion but cloud computing is about as secure as my Vauxhall Nova was (Was stolen 5 times lol)

if you're data has no financial potential then use fusion if you data is valuable avoid clouds.

My bank has been hacked twice in 6 years and virgin media last week, I have no faith in secure cloud computing at all.

I know it's time to upgrade my cad so going to buy this package I think
http://www.cadandgraphics.com/tupro20plwic.html?gclid=CPHLw8jE49QCFee77QodVWkGUw

Seems very good value for a semi pro workshop solution.

Davek0974
29-06-2017, 06:04 PM
I know people love Fusion but cloud computing is about as secure as my Vauxhall Nova was (Was stolen 5 times lol)

if you're data has no financial potential then use fusion if you data is valuable avoid clouds.

My bank has been hacked twice in 6 years and virgin media last week.

I like Fusion, yes its cloud but you can save copies locally too. ;)

Desertboy
29-06-2017, 06:14 PM
I like Fusion, yes its cloud but you can save copies locally too. ;)

I've heard Fusion is good but the guys I work with everyday keep telling me to buy solidworks but at 20k not been in the mood lol, especially as they upgrade every year so I would have to go the 5k a year upgrade path lol. I believe Fusion is not free if used commercially but never checked the licensing out because if I did change cad it would be to solidworks as I have never come across 1 manufacturer that does not use solidworks now and I've dealt with injection moulders, vac formers & plastic/aluminium extruders on a daily basis for 6 years.

If I couldn't save locally then it would just be a joke of a program but being able to save locally does not make it secure just at least usable.

Clive S
29-06-2017, 06:23 PM
You can import files from SW to fusion360 if that helps. Being secure for the average hobbyist is not the end of the world when it is free.

Its hard to find a free cad cam package as good as fusion.

Clive S
29-06-2017, 06:27 PM
the frame could i make it out of 50x50x3 mm or do i need to use bigger and heaver steel?
i found this shop in holland i think the price is ok because i need supported rails of 3 meter long

https://www.hardware-cnc.nl/en/shop/lineair-guides-parts/supported-round-rail

Anyway getting back on track with your build. I would start with the design of router bed first and then decide what you need to stand it on. Or build it all in one piece. In my opinion 50x50x3 is not strong enough for what you are trying to achieve

Desertboy
29-06-2017, 06:53 PM
Anyway getting back on track with your build. I would start with the design of router bed first and then decide what you need to stand it on. Or build it all in one piece. In my opinion 50x50x3 is not strong enough for what you are trying to achieve

2 years ago I had to build a punching machine (Hydraulic) for plastic I built it from 3mm box section AND it's not strong enough I have to run it about 1/4 the speed I built it to run to get decent results and I'm punching Polyprop. Any faster and the holes are not accurate! I heat the punchs to 230c as well to reduce stresses using nozzle heaters from injection moulding machines.

I would think a minimum of 7mm would be needed if I wanted to make a steel router.

I was shocked the stresses of punching plastic the aluminium casting we made wasn't strong enough to resist the forces and we had to recast in steel and on the first attempt the steel shrunk too much so we had to recast and grind to fit.

If I had a cnc machine then would have been a lot more fun lol.

pet30
29-06-2017, 09:25 PM
my cnc is only for routing parts drilling etc the max thicknes is 50 mm MDF for shelves and cabinets 18 mm thick.
i know everything needs to be strong but if i weld the frame and bolt it to the ground is it not strong enough?

i was thinking making the frame like this

22030

22031

Davek0974
30-06-2017, 11:50 AM
I would add some triangulation trusses to the box frames - stop it twisting etc.

If you were really good at carpentry there is no reason the base could not be made from timber, it would mean very tight joints and good design but the forces to resist for machining wood are not massive so i see no reason it could not be done. Cheaper in wood? I doubt it? Easier to build - not for me as i dislike wood and like metal but for a carpenter???

Anyways, that frame needs triangulation or it will wobble each time the spindle changes direction rapidly.

pet30
30-06-2017, 12:45 PM
Well a construction wooden beam is 68mmx38mm and kost about 1€ per meter
steel 50x50x3 kost about 3 to 4 euro a meter

so it will be a lot cheaper but jes then i would make it with haf lap joist and srew en glue everything together
everything thats steel will be bolted trough the wood .

and triangulation trusses in both way's?

Davek0974
30-06-2017, 01:37 PM
and triangulation trusses in both way's?

Definitely - the frame has to resist the thrust created by the spindle changing direction in all directions so a good sturdy base is essential. Downwards it needs to resist the weight of the material plus the force of the drill or tool etc, no sagging or spring so again, a good firm base is needed.

Boyan Silyavski
02-07-2017, 03:11 PM
Without triangulation if you use min 80x80x3. Otherwise as others said.

Forget about "wood" and a "machine" in one sentence, "machine" and "steel" go better.

You constantly use the word "cheap" but i wonder how much you would charge for a custom kitchen and so in Germany? As i know what we charge here Germans in Spain and they find it relatively cheap. Forget that word, make the machine and start making money.

Desertboy
05-07-2017, 06:44 AM
You could save yourself a lot of money and time if you buy this but how much it would cost to Germany I'm not sure.

http://www.ebay.co.uk/itm/Linear-motion-Assembly-for-CNC-/292171369321?hash=item4406c54b69:g:SOwAAOSwCQZZLel Q

I see an almost finished gantry when I look at this

Boyan Silyavski
05-07-2017, 07:45 AM
I can not find in posts if sb mentioned it earlier but I think that from Germany this is the best thing he could buy http://www.ebay.es/itm/CNC-Set-20x-1900mm-2x-Linearf%C3%BChrung-4x-Linearwagen-orange-Linear-Guide-Welle/322570006540?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

Ok, Not Hiwin. But Cheap, in Germany and supported square rail.

pet30
06-07-2017, 01:40 PM
thx for the link very interesting
I have changed the design of the machine a bit
Everything will be made out of 80x80x4 mm thick steel
My gantry way's about 50 KG of steel.
I think the supported rails way about 6.6kg and the Z AX about 10 kg .
So in total ist about 66.6 kg but maybe take 80 kg just to be sure.

can i use these motors with a r&p system?
i was thinking going the mechmate way : they hold the pinion against the rail with a spring.

22099

22100

the machine is still in design fase so i can change a lot so if u guy's have more advice let me know

thx

Boyan Silyavski
07-07-2017, 08:46 AM
You could move 60-70 gantry with 2x 3nm nema 23 motor driven at 70VDC, as most people on forum do.

The motor you show is nema 34, will have more inertia. Ok, looking at the inductance of it its not too bad, i could say its even good. But you will need to drive it at least 110VDC as per its chart, or even better use 230V main power drives, which are much more expensive than AM822.

pet30
07-07-2017, 10:25 AM
for software i would like to use estlcam ist a cad and machine sofware together and very easy in use.

is there a set of nema 23 that u reccomend or do's it not really matter only that they need to be 3nm?

What about this set?

http://www.benl.ebay.be/itm/DE-Free-Wantai-3pcs-Stepper-Motor-57BYGH633B-Dual-Shaft-3A-270oz-in-6leads-/222559669843?hash=item33d1970e53:g:vpcAAOSwiQ9ZR3a F

Boyan Silyavski
07-07-2017, 10:54 AM
this is the short motor. You need the longer Nema 23 . Could buy it from Uk, Price is good and they have full kit with drives, https://www.cnc4you.co.uk/Stepper-Motor/Nema23-3.1Nm/Stepper-Motor-3.1Nm-60BYGH301B-Nema23

pet30
10-07-2017, 12:31 PM
could this one work ? 22164

Boyan Silyavski
10-07-2017, 01:59 PM
could this one work ? 22164

it could but is not the ideal. I pointed you the previous message to the ideal. Building the CNc you can make like 500 mistakes. When you are not sure which, what why, just follow the recommendations :-) or look more carefully into the data. And when you dont know what it means, follow the ...

22166

pet30
13-07-2017, 11:53 AM
witch driver is the best for those stepper motor's ?

can i use arduino uno with the drivers?

its because i want to use estlcam and it works with arduino uno or xPRO V3 Controller Stepper Driver so can i use these with the drivers?

Clive S
13-07-2017, 12:13 PM
witch driver is the best for those stepper motor's ?

can i use arduino uno with the drivers?

its because i want to use estlcam and it works with arduino uno or xPRO V3 Controller Stepper Driver so can i use these with the drivers?

AM882 are a good choice for the drivers. With 68V power supply.
Why would you want to use arduino uno to run a router?:hysterical:
Any software will work with the drivers.

pet30
29-08-2017, 01:23 PM
Got the steel since friday i was a lot and very heavy.
this weekeind i started to weld everything together with a small inverter and it works very well.
Just a question do i need to bolt the machine to the floor ? do i need to put rubber between the bottom of the legs and the floor to have the less vibrations?
22692
2269322694

Clive S
29-08-2017, 02:38 PM
Just a question do i need to bolt the machine to the floor ? do i need to put rubber between the bottom of the legs and the floor to have the less vibrations?

No. No need to bolt the machine to the floor I have mine on castors but when it is in place I lift it off the floor on wooden blocks otherwise it would walk about.

Neale
29-08-2017, 04:50 PM
Like Clive, my machine sits on wooden pads under each of the adjustable feet, which can be lifted to make use of the castors. The plan was to make the machine mobile so I can pull it away from the wall if I needed to work on long lengths of material. Wood or hard rubber (like the commercial adjustable feet) are fine.

pet30
04-09-2017, 09:58 AM
just a question

the supported round rails ( not hiwin etc)

22709

those carts how many kg can they carry , because my gantry is becoming very heavy.

My rails are the SBR 20

pet30
13-10-2017, 09:35 AM
i got a lot of work done this weekend

the machine has finaly got the rails mounted and they run very smooth
the gantry rails mounted
everything is welded and made grinded for paint
next weekend i will paint the machine

then i need to move the machine on its right place level

mount the r&p, the motor's, drivers etc so a lot of work but i am very happy with the result so far

a couple of my friends where shocked to see this
23027

Boyan Silyavski
17-10-2017, 01:26 PM
It starts to look very nice. There is something in that metal structures that i like...

pet30
18-10-2017, 02:51 PM
thx

its still a lot of work but i hope everything will work out very good.

https://www.cnc4you.co.uk/Stepper-Motor-Kit-3.1Nm-x-4-Axis-Nema23

is this the best set for the machine?

Neale
18-10-2017, 03:39 PM
there will be a lot of replies that say "68V PSU and AM882 drivers." I agree - you are building a good machine so don't spoil it by using under-powered motors. Those motors themselves would be fine but they will really deliver better performance at a higher voltage and drivers to match.

pet30
23-10-2017, 11:34 AM
SO 68V PSU and AM882 drivers is the better opion then?

the steppermotor's are they ok and i can mount them directly to the rack&pinion ?

or do i need to use a gearbox of some sort?