Mid range design cnc machine router discussion
Mid range design cnc machine router discussion
Thanks for starting this thread Paul...
As you guys can see, we are serious about developing a decent open source design.
This is the thread for the mid range design. Benchtop size.
So what do you guys think lends itself better to a midsize design...
Igus W bearings?
Split bushings on supported rails?
Your thoughts?
Mike...
P.S. Here's an Igus design concept...
Does the 80/20 bearings suggest a mid level design, or because of the precision, should that be considered an entry level design?
(See attached)
Mike...
mikesch....the 80/20 linear bearing would be an entry level.
I would personally recommend drawer slides for a machine before I would use the 80/20 bearings - for an entry level machine, that is.
Scott
Consistency is a good thing....unless you're consistently an idiot.
ok , think this is a more suitable thread for this ,
this is the design of a machine im working on , sorry that the fonts are out in the dfx files , it seems to make them bigger than the original , trying to sort that , but not had time yet
most of it is mdf with some steel parts
i do not have many tools available , so limited to having a hand drill and hand tools.
as to steppers and controls i purchased a www.stepperworld.com fet 3 economy system , i could of used other steppers and built my own controller but in the end decided to go for that package as it seems a good deal , and just left me with the machanical bits to make
theres 5 dfx files that should be attached the drawings are not complete i still have a couple of parts to draw, and assembly views of the machine , i am photographing it in verious construction stages but not uploaded any as yet
its my first cnc machine so any comments would be helpfull
for the cutting tool i am planning on using a bosch pof500a router
the steppers are 60g ones and hope they will have enough power
but the fet 3 controller would easy drive bigger ones if needed
is it just the machanical bits or are you looking at the controller also
i have been conidering developing my own stepper driver board but have not had reason to do so as yet but may have to yet
i have been considering a usb based one (that would offer com port emulation in software so programs like kcam may be used with it
i seem to have a problem with kcam and my laptop's printer port so may need a different controller if i do not manage to solve it
not shure how accurate this machine is going to be but anything has got to be better than my work , that beeing the other problem i have tryed to solve in making it , in that critical cuts to the mdf can be made at the cutting shop , and not left to me and a saw (well 10degrees out for me is about right on a bad day as is drilling with a -+ 5mm accuracy )
hence the need for a cnc that can work better than that
Dave
A while back I gathered several parts necessary to build my CNC machine. I acquired Thompson linear rails for X, Y, and Z axis. 48" X 24" table. I have 3 Servo motors and quite a bit of plate aluminum. All this has been sitting for about a year as other things came up. Would this be considered the makings of an intermediate or mid-range design? I'm really out of the loop and would like to get this up and running. I need controller boards and screws, and software. I have the router and a computer.
Let me know if this is the right place for me to watch or if I should be in the beginner area or whatever.
Thanks.
Darren
With Thompson rails, I would consider what you have as the beginnings of a high end machine, especially with that pile of aluminum you've got.
You could watch all the open source threads, they will all give you design inspiration.
I would like to see a high end thread someday, but somebody needs to come to the plate with the knowledge, and the parts to build it. Maybe that somebody is you?
Mike...
I don't think I'm the guy I am very handy and am quite capable of building this machine but I know little to nothing about CNC. I just know what I've read on the forums on this site and have forgotten most of it over the last year. I'm trying to ease back into it though so I can get this investment up and running. I hate seeing it sitting there in a pile. Last I remember is I was trying to find a deal on Gecko boards... a bit of an investment. I'll keep an eye on this forum though as it should be interesting.
still not shure if my post is in the right thread , think by the way things are going here 2 threads may be a good idea , for a midlevel design , one for simple construction and one that requires machining of parts ,
my design is almost in the hardware store catogory but seems its to big for there
its a 900mm *500mm *100mm cutting aria design that could be made with minimal tools
and i am working to a budget of £400 (including controls and steppers)
and thats all parts new ,
it would just fit on a table top as the dimentions of the base are 1136mm * 930mm
hmm 47" * 38" approx if my conversion is right
its mainly for working with wood and ply , but trying to build it with enough strenth to mill alluminium also so i have basicaly uprated the Igus design a bit , and some minor changes to make it look a bit better and put the cutting tool more centered on the x axis
as to accuracy well if i can get +-0.5mm from it it would suit my needs but hopefully it will be a lot better than that
with m10 bar i get should get 0.005mm per step with stepers at 1.8deg per step
to darren , sounds like thats going to be one nice machine your making , but from the tools i have to build one from i would need a cnc to make the parts
as to rails i decided to use a steel tube with bearings as runners as this seems to offer good strenth , and easy enough to make ,
i ended up using 20mm staneless bar as it was available from a local suplier , but could use up to 30mm dia bar or tube , depending on the use
sorry about dimentions all being metric for a rough conversion theres 24 mm to 1"
I'm not seeing the enthusiasm for a mid level machine like I am for the hardware store design.
I thought a mid level machine would be built from igus rails and bearings, or supported precision ground shafting and split bearings... but the interest doesn't appear to be there.
Is it the cost, or is the the precision required? A mid level machine is probably a skill level "mill 1", i.e. requires you to already have a mill to machine parts with.
What do you think?
Mike...
well after all the chatter there about what bits are available from local hardware stores , and then listing tools required to complete the designOriginally Posted by mikeschn
ok heres my 2 halfpence worth
i need a cnc , so set about building one , i looked at some of the construction methods used on a number of machines , and took into consideration the tools and equipment needed to build it , then i spent some time sourcing parts ,
it needs mdf for the main structure ( available form local hardware store or wood shop) i have to add here that a lot of hardware /wood shops offer a wood cutting service as long as the cuts are at 90 deg so square /oblong pieces end up accurate , although on this design i have still a lot of cutting out to do to shape some of the pieces but you get what you put in
some effort with a hand saw makes it worth it in the end
i decided to use steel angle iron for suports and bearing holders , these reqire drilling and fileing , no milling
the pricision rails well i originaly designed the machine to use 30mm dia 1.5mm thick tubeing , so something like curtain rods may be used although by using this method anything from 20mm to 30mm bar or tube could be used if it has a good surface , i opted to take an expencive route of using 20mm stainless steel bar for these , as i want to be able to machine aluminium
the size is scailable , and there is a +200mm axis requirement for the lenth of the carrage
i do not have a mill , and only hand tools to make the machine from the only singal part that is going to be a problem to make is the coupler to mount the threaded bar to the stepper motor , this is going to need a pillar drill i think
it could be built using a hardware store only , the steel parts could be made from aluminium angle if , but not shure if it would offer the strenth so opted to use steel
from the sounds of it hardware stores in the uk do not offer the same as in the us , but there is a good base of steel stock ,bearing suppliers here in the uk that makes all the parts available reasonably localy or online so do not see the problem there
but there draw slide version seems a good idea, but would say that the big diy/hardware stores in the uk do not seem to offer that style of slides
anyway i managed to fix the problem with my dxf export for the files
and uploaded them to my website http://www.whipy.demon.co.uk
cost well you get what you pay for , if i used 9mm mdf instead of 18mm and used tube instead of bar for the rails and aluminium angle instead of steel then it could be built cheaper , but would be more suitable to a dremill than a 500w router for the cutter , and would limit the materials that could be cut , then almost all the parts would be available from the local B&Q or Homebase here in the uk , the exception being the threaded bar but CEF a trade supplier also throughout the uk stocks this and offer cash over counter for it , and bearings well google for a local supplier theres quite a few
anyway i'm going ahead with this design so feel free to comment on it ,
or come up with something copleatly diferent ,i guess once i get it built there will be problems that need iroing out , i just descovered that the router mounitng will also accept my drill so gives me more tooling options
Dave
ok so im not perfect
my design needs a lot of reworking to get it something like
i have finished the metal parts required , and have decided to redesign the MDF parts
i still plan on using the metal parts but want to try to get rid of some problems i can see with the current design
like adding some form of supports along the leanth of the rail to stop flex
one of the things i originaly wanted to do , but in the end i decided not to but am going to have another go at is
the big diy stores offer a wood cutting service , as long as the cuts are at 90deg ( so thay wont cut angles cutouts etc , i want to be albe to go to the store and with std size sheet ask for it to be cut down , then hopefully i should only have holes to drill
thay use a machine that is reasonably acurate and you end up with 90 degree cuts
at the moment the design uses 3 sheets of mdf and there is quite a bit of srap , and alot of extra cutting to do once i get the bits home
i seem to be the only one posting in here could do with some input
anyway after some tests of the stepper world fet 3 economy system looks like some bigger and better steppers are going to be needed , have not decided if to build another driver board , but it looks like i may need to
dave
Hey Dragon,
Do you have some photos of what you are doing?
If we can see what you are up to, we'll likely have ideas for you... or at the very least, some ribbing!
So what do you say? Share a photo or two!!!
Mike...
Unfortunately, you may find that the FET might need to be replaced. I think I've only heard one person say they were happy with the performance they got from it. A HobbyCNC or Xylotex driver will ususally give you at least twice the speed. You may need bigger motors as well, not sure what you have now?Originally Posted by achiestdragon
Gerry
UCCNC 2017 Screenset
http://www.thecncwoodworker.com/2017.html
Mach3 2010 Screenset
http://www.thecncwoodworker.com/2010.html
JointCAM - CNC Dovetails & Box Joints
http://www.g-forcecnc.com/jointcam.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
ok
first pic , a pile of bits ,
well the metal work , router , vac (for dust extraction) , some wire, 2 relays and a contactor (for power control of the vac and router) , and a stepper world steppers ,controller and psu
dosent get much better
second pic some idea of what sort of of tools are avalable , here showing the vice in the process of making the bearing holders with two compleated ones painted
third picture , well now got all 6 compleated bearing holders ( waiting for bearings and 4 still to paint along with the stainless runners
the bolts will need shortening but will do that when i have the bearings
the long support rails for the base bed are now finished and painted also
the reworking of the MDF parts is comming on well so far also ,
im looking to be ordering the bearings soon and the mdf in a week or so
leaving only a slightly out of the way trip to pick up some m10 threaded bar
so should have the thing assembled in 3 to 4 weeks hopefully
then it will be down to the steppers and driver , i dont think they will be up to the task , so will be looking to source some that are ,
btw the only power tool used so far is an electric hand drill , as you can see with a wibbly wobbly vice , and basic tools its getting there
the stepper world driver should be able to drive bigger steppers , as to speed it will drive them faster than the steppers will turn so think with better steppers this may be ok , but i may need to change the driver fets to better ones , i have been playing around with them on the bench , it seems that the steppers are the limiting factor with it
i set the software to give me 200ipm (@5080steps inch)and the driver was clocking the steppers fine , just way too fast for it to turn them so theres hope for the driver yet
will need to get the machine set up then i will try it with the steppers and try some different ones on it
maybe there stepper package would suit a minature cnc with a dremill as the cutting tool better a future project maybe
Dave
Whats the spec for this machine? I.E. What cutting volume size, precision , accuracy, speed, size of cutter, size of spindle, materials to be cut?
well the cutting aria is 900mm *500mm *100mm (approx 35"*19"*4")Originally Posted by fyffe555
it should be scaleable with not much effort , and only minor changes (to bed thickness and bed suport rails hopefully it should be able to do 8'*4'
the cutter is a bosch pof500 router a 500w router , but also found i should be able to use a bosch csb500w hand drill in the same mounting (but lose some cutting aria hight , but have a chuck for tooling ) but should be easy enough to modify for other power tools / cutting tools
speed well will find out , looks like the steppers i have are going to be very slow so it will need better ones ,
materials , MDF,ply ,soft woods, aluminium and plastics are the goal for it , anything else will be a bonus
trying to get the design so it will scale up or down but i am limited to the size of my workbench (concrete coal bunker see pic in previous post )
the stepping should give 0.005mm accuracy but would say 0.01mm (about 0.00039") should be posable unless theres a flex problem but i got to build it first an see
im in the process of doing a lot of changes to the design at the moment
i am trying to make it easier to make and do more to eliminate any possible flex
anyway no garanttees until its finished
dave
Dave,
Sorry, I was trying to ask what the target specs where for this thread and the Mid range design #1
Andrew
not shure , i moved over to this thread from the hardware store cnc during initial disusions there that pointed to this machine being too big for that ,Originally Posted by fyffe555
and pointed to some bits not beeing avalable from the local hardware store
(there using the same bits there now anyway )
anyway
there seems little interest in this thread and the discussions in the hardware store seem to be following the same route im still not shure if i should be posting the design here or there
it did look like someone ( sorry can not get name up while in the reply box)
was going to do a design for one with comertial sliders and machined aluminium parts , (big task ) but should be a hi quality machine
but they seem to have backed out
shame , would like to have seen that
Dave