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arg123
11-12-2015, 09:07 AM
Hi all,

My name is Argiris and I am from Athens, Greece. I am a pilot flying for Ryanair but also a hobbyist handy with power tools, computers and arduinos. My cnc experience is a scratch built 3d printer so basically a total newb.

Having my month off in coming January I was all set to build the Joe's cnc evolution machine.

The idea was to build a cnc router for personal use in a small farm in Corfu island that it will be able to cut a full plywood sheet but also be able to do some slow and rough cuttings in aluminum and maybe steel(small parts).

The base was to be welded steel tube and x,y-axis aluminum extrusions with angle iron bolted on them and v bearings
sliding on the angle iron.

Searching for epoxy leveling I run in to your forum and it is like a hard reset pressed. I have to start all over again by reading and learning all the new things in this forum but at the same time I don't want my month off to go by so I would like to build the base .

Can you please clarify few things for me so I will be on the right track?

Do I need to go that big on the y-axis(long axis) to cut a large piece of plywood or can I do it in 2 steps keeping the long axis shorter ? In that case what size of cutting area is recommended? Would I gain benefits by keeping it short as far as rigidness and no need for rack and pinion?

Rough cutting aluminum and steel is it doable or I should forget about it? Even at very slow speeds.

Would I go ahead and build the base based on one of your proven designs thus taking advantage of my month off and think of the rest later when I will have more time reading and learning from you? Meaning step by step from ground up.

Meanwhile I spoke to Vagelis(ba99297) member of your forum and he is already being a great help.

Thank you all for your time and forgive my ignorance.

Argiris

kingcreaky
11-12-2015, 08:34 PM
Argiris

welcome. Guess, all I can say here is be careful with your money. Lots of people here will vouch for me saying that spending money on "joes cnc kits and plans" will simply wet your apetite and lighten your wallet. You will make the machine, and it will cut material "for an amount time...." but what you will gain most is learning all the things that are repeatedly said on here in regard to the the flaws in both the design & materials its made of.


http://www.joescnc.com/kitsplans.php

Lots of people (myself included) make a machine to cut say half a sheet of ply, then quickly wish they had made a machine capable of accepting a full sheet.

So, my advice, is do it once, do it right. Unless of course (being a pilot) you have money to play with :D


If I was you, id make a machine with a length of say 2.6m, and a width of about 1.6m (a sheet of ply is 2.4 x 1.2) but you need to think of machining area. Make the y (gantry) the smaller measurement of the two, and look towards rack and pinion.

Plan to make a good wood router, if you do a good enough job it will do a "ok" job at cutting ali from time to time, but forget steel.

Happy to help with plans etc, once you give a clearer idea of what you plan (in terms of size)

arg123
12-12-2015, 09:52 AM
Thank you Kingcreaky

I was really lucky to ran into this forum just before I was about to start ordering parts. I can't judge Joe's cnc as I don't have the knowledge to do so but I will trust you all on that.

Yes the idea is for a machine accepting a full sheet of ply (2.5 χ 1.22 ) so the cutting area should be slightly larger for clamps etc.
Can anyone tell me the size of the base so I will not come short in the y(gantry) axis?

As per suggestions in other threads 80 x 80 x 5 steel tubing is a good option. Adjustability on the top rails and epoxy leveling is the initial plan.If the rack and pinion is the preferred way for the long axis, will the racks be bolted on the side of the top rails? Any extra consideration for the top rails then?

Help please

komatias
12-12-2015, 10:14 AM
Αργύρη καλωσόρισες.
Και εγώ Έλληνας αλλα ξενιτεμένος χρόνια. Σάμιος στην καταγωγή.

There are thankfully a number of suppliers on Greece that have rails and other parts but prices may be a bit high. With that in mind be prepared to spend 2000 euro plus if you want anything worth having.
Is your aim to have a working machine or to learn how to make one? I would imagine that you may be able to find good used machines around if you just want to get cutting.

Cutting wood and maybe aluminium is very different to cutting steel so wood machines may not be efficient at cutting steel, while steel machines will be too slow for wood and alu.


Before buying anything design it. Get familiar with CAD you will need it later. There are powerful free packages like onshape or fusion360 that will allow you to theoretically build your machine. Most of the standard parts are available in CAD format so it is pretty quick to model things.

Let us know how you get on and show us your progress

Γιώργος

arg123
13-12-2015, 02:46 PM
Thank you George,

I usually buy electronics from ebay and if I need aluminum from Misumi Europe.
My aim is definitely to learn how to make one. I set up a budget around 3500 - 4000 euros.
I was using sketchup before but now I am going to get a grip with fusion 360 for my 3d printing parts.

I will try to design the base looking at others build threads hoping that I will find the answer to my question about the cutting area(width) somewhere in the forum. Then maybe I will get some helpful comments.

Clive S
13-12-2015, 02:49 PM
Thank you George,

I usually buy electronics from ebay and if I need aluminum from Misumi Europe.
My aim is definitely to learn how to make one. I set up a budget around 3500 - 4000 euros.
I was using sketchup before but now I am going to get a grip with fusion 360 for my 3d printing parts.

I will try to design the base looking at others build threads hoping that I will find the answer to my question about the cutting area(width) somewhere in the forum. Then maybe I will get some helpful comments.If you add about 300mm to the length and about200mm to the width you won't be far wrong. When you draw it in cad you can check as it depends on what spacing's you use for your bearing blocks. Good luck with the build.

Then maybe I will get some helpful comments And you haven't had some already:rolleyes:

JAZZCNC
14-12-2015, 09:59 PM
Meanwhile I spoke to Vagelis(ba99297) member of your forum and he is already being a great help.

Vagelis is a very nice man he also makes Great wine please say hello to him for me.!!

With regards to your plans then my words of wisdom are Choose a sensible design don't go crazy regards build strength if all your mainly going to do is cut woods. Like has been said forget Steels and if you want best machine then I'll go further and say forget designing for Aluminium has well.?

Machine built to cut all materials is always a compromise, woods, plastics and softer materials mostly come under the same design class regards strength and cutting but Aluminium starts taking you away from what is optimum for this class. Which means pushing you into stronger heavier designs which start having negative affects on the machines main usage along with other negatives like.? Expense, complexity, performance with very little if any gain.

You don't need massive tube sizes and thick armoured plated tank like structures to cut woods etc. Aluminium needs it's own ideal design parameters and while it's possible to cut aluminium with a wood router it's very different to cutting aluminium correctly.
The design considerations for Aluminium which are mostly strength and cooling related both have negative affect on soft materials cutting with huge affect on your wallet to do correctly to suit both materials.

So design for wood is my advise and make it the best it can be for the intended purpose and leave the hard stuff for another build.!

Also don't need to design in Cad to the last tiny detail because things in the real world have a habbit of not fitting like they do in Cad.!! So just layout the basics to confirm lenghts etc and the design works also major components don't clash with each other. This does mean that you need to design with accurate component models or ideal models of the actual parts your going to use. Often I see people design using generic models only to find reality bite them when they don't fit in the real world like they did in the Virtual world of Cad.!! . . . . It also wastes a lot of valuable time that will be better spent building and learning than drooling at computer screen.!!

Good luck.!! . . . . . Oh and has the Lady's often find out Size really isn't everything it's how the tool is used which determines the pleasure.!. .:hysterical::hysterical: :hysterical::hysterical:

komatias
15-12-2015, 09:45 AM
When capital controls are in place and sending money abroad requires a bloody committee to approve, you try to make it right first time. Hence I see CAD being imperative in Argyris' case

The comment of "Beware of freely available CAD models" is spot on. Not all Nema 23 motors are the same, not all extrusions are the same. Luckily Misumi allows you to download their CAD files.
Best work to the drawings that tell you the expected tolerance.

JAZZCNC
15-12-2015, 01:44 PM
When capital controls are in place and sending money abroad requires a bloody committee to approve, you try to make it right first time. Hence I see CAD being imperative in Argyris' case

George Read what I wrote again and you'll see I Didn't say DONT use Cad I said don't get bogged down in trying to design to last detail. It's not required at this level and often IME helping others it actually slows down the process of building. Many times it leads to errors because too much reliance is placed on the Models and Cad without much thought for real world influences and differences.!

komatias
15-12-2015, 01:58 PM
No argument with you Jazz and yes real world influences play a major role. I was just strongly reinforcing the need to plan and that tools are available for this.

JAZZCNC
15-12-2015, 03:14 PM
No argument with you Jazz and yes real world influences play a major role. I was just strongly reinforcing the need to plan and that tools are available for this.

No worries George just read like you thought I'd said DONT need Cad which wasn't the case. Like you I believe it's very much needed but only to a point.!

arg123
15-12-2015, 05:00 PM
Thank you all

Clive, I meant to say helpful comments in regards to the dimensions. I will draw the base and I will add according to your suggestion and see how it goes.
Jazz, Vagelis is really nice, if he makes Great wine he is even nicer!!!

With wood and soft materials in mind I will try to design the base and post the drawings hopefully in a few days time. No previous experience with CAD(I can draw simple things) but I will try my best.
Plan is to start welding in January.

kingcreaky
16-12-2015, 10:03 AM
If it helps, the following is a Sketchup file, for the 8x4 router I built earlier this year

http://www.mycncuk.com/threads/8242-8x4-Wall-Mounted-Upright-ply-cutter?highlight=upright

sketchup file here ( http://buzz.pensys.co.uk/pensys/garage/chris_cnc_mycnc.skp )

Dont be under the illusion this design is perfect, or suited to your needs. But if nothing else it gives the dimensions necessary to facilitate an 8x4 sheet with a Z carriage of 160mm

ba99297
16-12-2015, 05:18 PM
VAGELIS IS BACK!!!!

Vagelis is a very nice man he also makes Great wine please say hello to him for me.!!

Dean and Argiris thank you for your good words.
Argiris is the one who make me restart my project sooner as I expected
I explained him about the community of mycncuk.com and how the people here help help help, and the most important selflessly
Personally i feel thankfull ...


Good luck.!! . . . . . Oh and has the Lady's often find out Size really isn't everything it's how the tool is used which determines the pleasure.!. .:hysterical::hysterical: :hysterical::hysterical:
Dean the ladies often tell these words to the "small tool" owners in order to console them.

And a little story about "tools" that shows the superiority of the Greeks (here we laugh!!!) who think that we are the center of the world.... (here we laugh again)

An African and a Greek stand on a bridge and pee. Underneath runs a river. They stand on the bridje back to back ( the one cant see but only listen the other).
The African in order to vex the Greek says
"I feel the river is Cold today"
and Greek replies
"And deep"
Argiris good luck give us some plans.

JAZZCNC
16-12-2015, 05:44 PM
Dean the ladies often tell these words to the "small tool" owners in order to console them.

Oh yes Vagelis this small "Tool" has been consoled many times and the pleasure was all mine. . . :yahoo:

Nice to see you back and would be even better to see more progress.!

komatias
16-12-2015, 07:20 PM
Oh dear, I am not the only Greek on here any more. Vaggo, looking forward to seeing your cutting machine too.

arg123
21-12-2015, 09:46 AM
Kingcreaky thank you for the files.

Looks really nice. Is it 3100mm in the long axis? Are you bolting the plates to the vertical frame first and then weld the cross members in place or have them made before with the 2 plates attached and then bolt them to the vertical frames? Can I pre-drill plates and side members using a jig in a bench drill then tap then start building the frames or I will be way too off?

Being new to CAD I spend the last 3 days trying o design a preliminary plan of the base. My main concern was to be able to design it parametrically so I can change most of it on the fly without having to redesign it again. So far it works well even though the design structure is like spaghetti code.

The base steel tubing is 60x 60 x 5 and the lower grid is 60 x 40 x 3.
The top right and left tubing would be bolted to the base for adjustment purposes if that is an extra benefit.Then epoxy leveling .
Any suggestions where to source the Hiwin rails? CAD files for them?

1687716878

Thank you all

Rufe0
21-12-2015, 10:29 AM
Any particular reason your using so many cross members? Just out of interest how far are they separated? Its certainly not a bad thing, the more the merrier I would think, however I think it would be significantly stronger in terms of deflection to have fewer cross members that where triangulated to the bottom rails rather than more with no triangulation. Having more would be beneficial though because it would support the sheet more evenly along its length.

arg123
21-12-2015, 10:48 AM
They are 311mm apart when the base is 2800 x 1650.I was thinking of having the lower grid of the base free for storing ply .

komatias
21-12-2015, 11:00 AM
Argyri,

Looking good!

The best place to get the Hiwin CAD models is http://www.hiwin.de/en/CAD_Configurator.html

Most cost effective way to get the rails and carriages is to go east. I would suggest that you get carriages with preload so they do not have any slop, it adds a bit to the friction but worth the extra effort.

In order to account for distortion etc I would suggest you build, level and then drill. A hand drill with good bits and a drilling jig like you describe is good as long as you make provision to straighten the rails afterwards. Have a look at installation instructions from HIWIN (http://www.hiwin.com/pdf/linear_guideways.pdf)which is similar to this NSK one (http://www.nskamericas.com/cps/rde/xbcr/na_es/E9008_Installation_Linear_Guides_Machine_Tool.pdf) for ideas on mechanisms to align and adjust for straightness and squareness, if you haven't already done so.

You could have the top sections on bolts but what would be the benefit if you epoxy level and drill afterwards? From our conversation it seemed that you were not thinking of moving the machine around so stripping it down is not needed. I would have thought that, should you crash the machine, you would need to readjust everything including the rails. In a rigid system, you will potentially only need to readjust the rails.

Regards

George

Rufe0
21-12-2015, 11:03 AM
Yeah that seems reasonable.

JAZZCNC
21-12-2015, 05:15 PM
I see a few things I would change but rather than put into words it's easier to show you. Most Should be obvious but ask if not sure.

The reason for top rail being longer at each is to recover some wasted bed space plus makes machine shorter. Also allows gantry to ride past the end so can use end of machine for standing boards upright or fitting 4th axis across end if required. Long overhang would be rear short would be front.

168801688116882168831688416885

arg123
22-12-2015, 10:46 AM
Dean,
Thank you very much for your help I really appreciated.
Smart way to increase the cutting area and add future use(4th axis)

Few questions and I think I am good to go.

Steel tubing for the whole base 60 x 60 x 5 ? Do you agree on that?

Length of the bed 2600 + 100 short overhang + 300 long overhang = 3000 total would that be o.k? Do the overhangs need to be braced?

What are the spacing of the cross members and the top rail supports in your drawings? No dimensions so I can't calculate.

Has anyone joined hiwin rails lengthwise let's say 1500 + 1500 to achieve 3000mm length. Is it doable for the home builder? ordering from BST automation 3000mm rails will make shipping cost way up.

Hopefully I will be start building in the beginning of January.

JAZZCNC
22-12-2015, 12:35 PM
Few questions and I think I am good to go.

Steel tubing for the whole base 60 x 60 x 5 ? Do you agree on that?

Well kind of but only has a minimum. I'd be more inclined to go with 80x80x5 on such large machine but 60x60 will work fine.


Length of the bed 2600 + 100 short overhang + 300 long overhang = 3000 total would that be o.k? Do the overhangs need to be braced?

What are the spacing of the cross members and the top rail supports in your drawings? No dimensions so I can't calculate.

Dimensions will depend on your needs and gantry etc. I only drew this frame to show you and save explaining via text.
That said the dimensions I used where based on previous machines I've designed and are very close to those you mention.
From memory the short overhang was 150mm and the large overhang is the same length has the gantry width. Bracing on large overhang depends on gantry width but if more than 300mm then yes brace it.

Here's a 4x4 machine built using similair frame design but with adjustable height bed. Frame is 60x60x5 box.


Has anyone joined hiwin rails lengthwise let's say 1500 + 1500 to achieve 3000mm length. Is it doable for the home builder? ordering from BST automation 3000mm rails will make shipping cost way up.

Yes it's commonly done on really long machines but does need careful fitting. Thou If possible I'd avoid doing it.

16890

mekanik
23-12-2015, 10:43 AM
Well kind of but only has a minimum. I'd be more inclined to go with 80x80x5 on such large machine but 60x60 will work fine.



Dimensions will depend on your needs and gantry etc. I only drew this frame to show you and save explaining via text.
That said the dimensions I used where based on previous machines I've designed and are very close to those you mention.
From memory the short overhang was 150mm and the large overhang is the same length has the gantry width. Bracing on large overhang depends on gantry width but if more than 300mm then yes brace it.

Here's a 4x4 machine built using similair frame design but with adjustable height bed. Frame is 60x60x5 box.



Yes it's commonly done on really long machines but does need careful fitting. Thou If possible I'd avoid doing it.

16890

Just a note, if joining rails the lengths have to be a different size, Hiwin Installation Manual says you should not have joints directly opposite each other,( I might have to join rails as i have already purchased some but need longer length)
Regards
Mike

arg123
06-01-2016, 12:40 PM
Following Dean's drawings I finalized the base design, so any comments and corrections before I start cutting would be appreciated.
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Blue steel (top rails) is 80 x 80 x 5.
Red steel is 60 x 60 x 5.
Green steel is 60 x 60 x 3. (trying to save on weight).

Top rails would be bolted to the supports for alignment purposes and use epoxy putty(later I would need some more details on that) and then epoxy leveling. Final length of the top rails (overhang) to be decided along the process.

What height from ground to top rails is recommended?

I ordered a straight edge 2000mm DIN 874/2 from same place Boyan did, thank you Boyan for posting the link,
and I also have a precision level 0.02mm/m so I hope I will have a quite true reference plane to start.

Thank you

JAZZCNC
06-01-2016, 06:35 PM
Following Dean's drawings I finalized the base design

Now don't go blaming me I had nothing to do with it. . .:hysterical:


What height from ground to top rails is recommended?

No fixed height really but the machine I showed is 950mm. Work out the height you want the bed and how much clearence you need and you'll get to the figure you need.

komatias
07-01-2016, 12:13 PM
The height of the bed will come down to ergonomics. The higher it is the more difficult it will be to load heavy material onto. As the same time, too low will make changing the cutters a bit difficult.

My preference would be to make the bed around desk height. The Americans say a typical desk height is 29" so 1metre would be just about right.