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My baby 15" x 15" machine
ok strictly it hasn't started yet, but i need to gather everything together and start planning this machine now as the mrs has all but given the green light due to a lovely PPI claim coming through unexpected.
so i'm trying to understand where to start and i suppose you start with what are you going to cut as this kind of sets the boundaries for what spindle you can use.
so.. i want to do some engraving in mdf, other nice woods, some acrylic so it can be lit up from the sides ect.. obviously there is some need for speed to keep the finnish up.. so before i try and cut corners here and say i want to use a dremel or something similar do i need to go all out and go for a water cooled spindle or is there something else out there that will suit my needs?
now once i figure out what spindle i am using i can then find out how big it's mount needs to be and from there i can work outwards and figure out rail sizes, screw sizes and then i can work on the frame to hold everything.
so with all the above in mind am i missing anything?
as a small note.. if i decided at a later date i wanted to cut alu with the machine would a need to design it differently than with the mdf and acrylic in mind
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Re: My baby 15" x 15" machine
Any reason you decided on 15x15 ?
and yes, cutting ally needs a very rigid build, and has to be designed in from the start.
Spindles ... it depends on your budget ? but a cheapish router will get you started. I've just bought a £25 one from Aldi.
ALDI - Sunday Special Buys 9th September 2012
I'll be fitting it to my build soon, as my Bosch router is about 20 yrs old and needs the bearings replacing.
You can change the router mount to a spindle mount at any time if you make it as a 'bolt on' to the main carriage.
Design the carriage so it has no interference from the router/spindle at the end of the gantry, else you'll loose some working area if you put anything bigger on later.
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Re: My baby 15" x 15" machine
15 x 15 was decided to cover off a 12" subwoofer ring if ever i felt the need to make one as this is what i used to do alot.. and i just thought 15" was a good size. if someone said well for very little extra you could go to 20 x 20 then i'd possibly go that far.. the idea with this machine is to keep the cost down, show the missus what it can do and for it to prove itself then i'll move on to a 4ft x 4ft so i can atleast cut half a sheet of material.
as for a cheap £25 router i'm willing to pay more for the spindle and i think from what i've read a router doesnt lend itself to variable speeds very well and from what i've seen of my own router it doesnt finnish plastic very well. also the standalone spindles are less bulky meaning machine design can be kept smaller and the collet extends alot further down than a router
so far i've seen these CNC 300W Spindle Motor & Mount bracket For Engraving Carving MILLING GRINDING | eBay
but i have no idea how good they are and what the limits would be.. also i suppose i need to consider psu for one? and how is the speed controlled?
or these 0.8KW MORE PRECISE WATER-COOL SPINDLE MOTOR ENGRAVING MILL&GRIND WATER-COOLED k5 | eBay
or to go as far as a 2.2kw, but again i just dont know.
i am hoping that as my machine is going to be small it wont need such a big motor, but again i'm open to ides if needs be and i need to spend £150 on a motor then so be it.
the plan is to get a list of all the parts i need and then go to one of the chinese guys and ask for a price for the lot which will hopefully save myself some money overall, but i cant get to this stage until i design the router
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Re: My baby 15" x 15" machine
when it comes to spindles, it doesn't matter that you have a small machine.
What matters is what you want to cut with it. Also, thinking of your woofer holes, you need to design in enough bed room for your sheet material, not just the cutting area.
I would say 300w is quite underpowered for anything except shallow engraving.
The larger spindles, and the water cooled ones are VERY heavy ! this will have to be considered into the design and motor/driver choice.
basicaly, lenght of screws/drive/r&P etc and length of rails/bearings determine the machine cost, (unles using extruded ally which is expensive). Most of the rest is the same cost regardles of machine size.
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Re: My baby 15" x 15" machine
presuming i am going for the 2.2kw spindle, having a working area of 15" x 15" has anyone got any advice on the diameter of screw i should use?
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Re: My baby 15" x 15" machine
15 x 15 .. a baby like mine 8 x 12 :) I want aiming to do the same as you , and some PCB's perhaps , mine off the shelf though, although someone did suggest now I havea small CNC I could build a bigger one with it well some of the parts at least, when I can get it to run that is , and its been sat there for a month now all I'm missing is a bloody cable! lol good look with the build..
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Re: My baby 15" x 15" machine
As no one has answered yet .. I'll risk the wrath of posting a reply :)
For this size, I'd say 16 would be fine. 5 or 10 pitch depending on motors and drivers
are you going for ballscrews or acme (trapeziodal) ?
did you read the MicroCarve thread I linked you ?
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Re: My baby 15" x 15" machine
i've been working 12 hour days for the past week and even working over the weekend.. what little time i've had i've spent with my family.. so no not read that thread yet... however i know how i want to make this machine i just need a few technical things ironing out.
16mm ballscrews is exactly what i had thought and it fits well with my budget so unless anyone has any good reason why i should go bigger then i'll likely go with them.
i'm on earlys this week with no call shift so i will be reading that thread at some point
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Re: My baby 15" x 15" machine
I didn't mean you should read it to change your mind ! just that it's about the same size as you are making, so it might be interesting reading :) screw size for instance .
Rich
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Re: My baby 15" x 15" machine
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Re: My baby 15" x 15" machine
nope i have all the welding gear now, but i'm still struggling getting my design down in goolge sketchup and until i do this i dont want to start, plus the money i thought we were getting got swallowed up by other things :/ life sucks atm
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Re: My baby 15" x 15" machine
cheer up cock. I agree with you wanting to get the design right before you start or buy things im in the same boat. Ive been desgining mine for months now, Ive just decided that i cant keep drawing ive just got to get on and try a bit lol. Im %90 there on design, the rest i can make up as i go along sucessfully im sure. Have you any sketches, plans etc to show, perhaps we could give you some input or a lift?
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Re: My baby 15" x 15" machine
Attachment 7212
finally getting somewhere with sketchup, i wanna run this past you lot before i progress this further
the 2 small piece of box section are 25 x 50mm steel box and i'm hoping to mount the router straight to them with a bracket i will design later down the line..
what i want to check is that the rails are not too far away from the router.. the box section the rails are mounted on is 50 x 50mm steel so that puts the base of the rails 75mm away from the base of the router support
and also the piece that the ball screw is mounted to is 10mm. firstly can i easily cut through 10mm steel with a holesaw? as thats the only way i'm going to be able to cut it? if not is 10mm thick ally enough considering how close the box section will be either side to support it?
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Re: My baby 15" x 15" machine
Wilfy
Swap your rails and bearing blocks round, put your blocks where your rails are now and have the rails move up and down with your Z axis.
Andy
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Re: My baby 15" x 15" machine
there are no bearing blocks in that picture yet...
let me show you where i got up to last night, i'm not 100% happy with it as i'm not sure what kind of bearing block i'm having for the ballscrew and the size of it
Attachment 7214
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Re: My baby 15" x 15" machine
Sorry thought the rails was on the front of the axis didn't realise is was the rear view.:stupid:
Put the blocks as low as possible and space them as wide in both ways as you can.
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Re: My baby 15" x 15" machine
guys whats the difference between using BK or FK blocks for the ballscrew supports?
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Re: My baby 15" x 15" machine
IIRC BK blocks allow you two mount them in two planes, perpendicular AND paralell to the screw. FK only allow mounting in 1 plane, paralell to the screw.
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Re: My baby 15" x 15" machine
hmm i only acctually want to mount parallel with the screw, i've seen some bk blocks though with no holes to mount parallel
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Re: My baby 15" x 15" machine
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Re: My baby 15" x 15" machine
so when i come to order my screws from chai.. if i ask for bk blocks they are 100% the ones i'm gonna get? the second ones u linked?
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Re: My baby 15" x 15" machine
Hmm before going to his shop I would of assumed so, but now looking at this: 3 SBR16 set+3 ballscrews RM1605+3 BK/BF12 +3 couplering | eBay Im not so sure.
Id suggest either wait for someone who has ordered from chai to post, or email chai direct and explain what you need. Im in this process at the moment and he is nothing but helpful.
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Re: My baby 15" x 15" machine
ok i "think" i've finished designing the z? axis i've included a picture with 2 views, what i'm looking for is constructive ideas, so far everything is steel i think although some of the plated bits might end up being aluminium i would rather weld everything than tapping steel/alu.
the small rectangle box sections are 50mm x 25mm and there is acctually only 2 pieces of 50mm square in there but these could also end up being 2 pieces of 50x25 slapped together depending on cost. the plates are all 10mm steel although the mount for the BK bearing is drawn at 5mm i'll edit that later.
this has 100mm travel which i am hoping will be enough it is a 15" x 15" machine afterall so is intended to be small work pieces.
so questions to anyone who can help before i progress further. does it all look like it will function.. i.e have i connected all the right parts in the right ways? a simple question to ask but i did originally put the ballscrew blocks on the same side as the rails.
secondly as i am intending to make this out of steel is there going to be alot/too much weight on a 16mm screw and rails on either y or z axis?
i can provide sizes of everything so far and if someone can tell me the weight of a piece of 50 x 25 steel box section i could work out the weight of everything.
Attachment 7221
also if you would like a better view of anything let me know
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Re: My baby 15" x 15" machine
before anyone gets to pointing it out, i've just realised the bearing blocks on the rails are over hanging the 50 x 25mm box depending on what you guys think i might just replace the box section with 10-15mm alu as the next size up box section would have to be 80x40mm iirc and this will push the router further away from the y axis which is something i am concerned about
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Re: My baby 15" x 15" machine
Hi Wilfy,
Has requested cast my eye.!!
For an all steel structure it looks Ok thou I would replace the 50x50 with 50x25 to bring whole thing closer to Y axis plus gain 25mm travel.
The back plate which fastens to Y axis needs some cross bracing, just relying on the top bot plates won't be enough. Also Because your using steel this z axis will resonate quite a bit more than an Ali Z-axis would. So it would be wise to attach motor to ballscrew with a timing belt to eliminate any resonance problems, I would consider running that top plate back between the Y axis uprights so the motor is at the rear.
The 10mm plate is a bit OTT and 5/6mm would be fine strength wise and infact better if you take the route I've just suggested has 10mm is too thick because it shortens the motor shaft protrusion to much.
Regards weight then it won't be a problem for the screw it's the motor that you use that will take the stress but a 3nm will easily handle it.
3mm wall 50x25 weighs 3Kg/per Mtr
If you can use Alu then I would has it handles resonance better but what you have drawn will work fine.
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Re: My baby 15" x 15" machine
the reason for using 50x50 was to allow spacing for the ballscrew and it's bearings but i'll re-think to try and bring it close.. plus using all 50x25 will be a bonus.
i had planned to use timing belts so i'm glad we are on the same page there.
the back plate which fastens to the y axis i am acctually considering using alu or steel plate in place of the box section as wont be able to use 50x25 box in the way i have in the drawings as the bearing blocks are 60mm wide with the holes at exactly 50mm spacing so i need to consider either 10mm alu or 6mm steel are both of these stiff enough if i'm using a piece of 370 x 170 plate?
and thank you for your input so far it's nice to have your mind put as ease especially considering i'm adapting other peoples ideas but realisticly drawing this blind
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Re: My baby 15" x 15" machine
If you are buying steel, these guys seem to be having a sale on at the moment, they also list the weight per metre wilfy:
100mm x 50mm x 3mm Mild Steel Rectangular Box Section - 1051216-1m
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Re: My baby 15" x 15" machine
Wouldn't want to be paying their normal price, even their sale price seems expensive to me.
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Re: My baby 15" x 15" machine
Quote:
Originally Posted by
D.C.
you my friend are a star :D i've bookmarked them for future reference.
after the great advice from jazz earlier i've set about re-designing and i acctually feel much better about the one and it should bring everything close to rails aswell as giving me less work
Attachment 7244
the green is the front where the router is bolted to, i aint had time to put that in but wanted to make this post before i go bed. it is just 50x25mm box with a 5mm steel plate on the front it's opaque so u can see the bearings underneath
the 2 rear views are my current options... due to the bearings being 60 and 62mm wide i need to either use 60x40mm box x 3 the total here is 900mm over the 3 pieces which using a rough math from jazz's earlier post i get them 3 piece at 4-5kg total or i could use a big 15?20? mm slab of alu as per the 3rd picture.. this will bring the design 20mm closer to the Y rails but more crucially it'll weigh a hell of alot less...
i would rather stick with steel as this is going to save me alot of money a rough guess see's the piece of the alu at £30 and the steel around £10 and thats before i go to a supplier with a full order with the hope of a price reduction... does anyone have any good reason why i should choose the alu over the steel?
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Re: My baby 15" x 15" machine
Quote:
Originally Posted by
martin54
Wouldn't want to be paying their normal price, even their sale price seems expensive to me.
Really? I thought that was a pretty decent price. :(
Where are you getting yours from?
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Re: My baby 15" x 15" machine
I got a price from a local company DC, was quoted £36 for a 7.5 mtr length of 50 x 50 3mm box. Downside was that they would only sell me a full length which I didn't really see being a problem with what I would need. Company is called GM Steel but not sure if they would ship or what shipping would be,
Point is that if you have someone local it is sometimes a good idea to pop in & speak to them, had other local suppliers for various things who have offered decent prices when you went to see them, especially if they knew you had been looking on the net. Face to face is always better than phoning from my own experiences.
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Re: My baby 15" x 15" machine
Quote:
Originally Posted by
martin54
I got a price from a local company DC, was quoted £36 for a 7.5 mtr length of 50 x 50 3mm box. Downside was that they would only sell me a full length which I didn't really see being a problem with what I would need. Company is called GM Steel but not sure if they would ship or what shipping would be,
Point is that if you have someone local it is sometimes a good idea to pop in & speak to them, had other local suppliers for various things who have offered decent prices when you went to see them, especially if they knew you had been looking on the net. Face to face is always better than phoning from my own experiences.
Martins correct shop around at your local steel merchants. I pay between £24-28 for 50x50x3 at my local steel merchant. 7.5mtrs is standard lengths they come in so if they won't deliver or don't have transport suitable to move then Workout your rough lengths then take a grinder with cutting blades and rough chop to size or lengths that are more manageable. Most steel merchants will let you plug into wall before miss a sale.?
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Re: My baby 15" x 15" machine
Same applies if they know you can buy online at a much cheaper price, some places will stick to their guns but others will try to give a better price rather than lose a sale completely.
Never thought about asking if I could plug in to cut lengths Jazz as I thought they may want to charge me a cutting fee. Generator, chop saw & grinder go in the back of the car & away I go lol.
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Re: My baby 15" x 15" machine
It doesn't take long to cut through 50x50 3mm box section by hand with a hacksaw...just make the minimum number of cuts to get it in the car and do the rest at home.
The company I got my steel from cut it to length for me for no extra charge, but evidently they didn't know how to use a tape measure as some of the lengths were wrong! Luckily they were too long so I sorted it out. Not complaining though as they gave me some freebies to practice welding on which were very useful :)
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Re: My baby 15" x 15" machine
It doesn't take long to cut through 50x50 3mm box section by hand with a hacksaw............ The older you get the more difficult it becomes Jonathan lol
Think I have reached the age where I need all the help I can get !!!!!
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Re: My baby 15" x 15" machine
i love how cutting box section is more interesting than my machine :(
one bit of input for anyone cutting steel, make sure you get nice thin steel cutting discs they slice through like butter, big thick grinding discs are no good for precision work.
i'll have an update 2nite.. it would have been nice for some input on wether i should use the 20mm alu plate or stick with steel and use 60x40mm box
Quote:
Originally Posted by
wilfy
you my friend are a star :D i've bookmarked them for future reference.
after the great advice from jazz earlier i've set about re-designing and i acctually feel much better about the one and it should bring everything close to rails aswell as giving me less work
Attachment 7244
the green is the front where the router is bolted to, i aint had time to put that in but wanted to make this post before i go bed. it is just 50x25mm box with a 5mm steel plate on the front it's opaque so u can see the bearings underneath
the 2 rear views are my current options... due to the bearings being 60 and 62mm wide i need to either use 60x40mm box x 3 the total here is 900mm over the 3 pieces which using a rough math from jazz's earlier post i get them 3 piece at 4-5kg total or i could use a big 15?20? mm slab of alu as per the 3rd picture.. this will bring the design 20mm closer to the Y rails but more crucially it'll weigh a hell of alot less...
i would rather stick with steel as this is going to save me alot of money a rough guess see's the piece of the alu at £30 and the steel around £10 and thats before i go to a supplier with a full order with the hope of a price reduction... does anyone have any good reason why i should choose the alu over the steel?
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Re: My baby 15" x 15" machine
ok i pushed ahead with the design with the thought of keeping the 60x40 in.
so this is 90% of the way there i just need to chuck the motors in.
Attachment 7252
the colour coding is basicly for me so i know which parts form each axis... for the x axis i'm looking at twin screws driven by one motor from the centre with a timing belt, i would have liked to have used one screw to keep the cost down but i imagine you guys will tell me thats a big no?
can you guys see anything wrong with this design?
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Re: My baby 15" x 15" machine
Wilfy ok I'm new as well but do you really need 2 screws on a machine this small. I know why they say use 2 but that's normally on a much wider machine.
Oh and sorry about hijacking the thread, I would have comented on the build if I could have added anything constructive.
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Re: My baby 15" x 15" machine
Sorry about that wilfy, my fault for asking non specific questions on your build thread. I'm so used to shopping online that I hadn't considered doing some actual real world shoppin, it seems so antiquated, like having CD's or a television...
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Re: My baby 15" x 15" machine
haha it's ok i was only joking anyway.... if i need something answering i'll go straight to someone in a message, i just like to see the discussions round here as it helps me to understand why people recommend the things they do...
2 ballscrews on the X axis is me really covering my arse, if someone says its not needed then thats brill for me.. i just considered the extra screw as this thing is starting to look quite heavy.
the total width of the the whole machine is around 800mm which is double the cutting area i'm happy for this to be as it is, i know i have likely over engineered some parts but i'd rather spend a little bit extra to be sure.. also it might help should i want to machine alu further down the line.
if anyone can shed some light and let me know if i need 2 screws or not and also say if i need to strengthen anything else then that would be great. any information needed just say and i'll sort it out.