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turpija
04-09-2012, 07:50 AM
here is fairly small machine intended to be mounted on table
outer dimensions will be about 1x1x1m
and working area is somewhere around 700x700x200mm or slightly bigger than 2x2'

here is visualization from solidworks, missing spindle with mount and table (which hopefully will be a vacuum table sometime in future)
http://turpija.net/images/stories/iron-cnc/01_01.jpg

got some metal cut
http://i.imgur.com/pc2l6.jpg

bevel it a bit
http://i.imgur.com/AHNyz.jpg

and start cleaning
http://i.imgur.com/WADCe.jpg

nice and shiny ;)
http://i.imgur.com/FOKSx.jpg

parts cut with waterjet
http://i.imgur.com/X75vN.jpg

...also needs cleaning
http://i.imgur.com/fmgRW.jpg

a little bit of assembly
http://i.imgur.com/fPWgC.jpg

and alot of drilling
http://i.imgur.com/9VDQw.jpg

this is how lower part should look like, just needs some holes and tapering
http://i.imgur.com/WvL6f.jpg

next thing on menu will be welding ... so stay tuned

there is a bit more pictures on my website if you wish to take a look ...

HorridHenry
04-09-2012, 07:58 AM
I thought mine would be heavy when built but yous must weigh at least 50/60 kilo's?

louieatienza
04-09-2012, 11:33 AM
Nice work!

harryn
04-09-2012, 11:35 AM
Thanks for posting your build. I looked at your blog and saw the anti - corrosion liquid bath with antikor. There is a company in Belgrade in the anti-corrosion business, but not a lot of information on the liquid itself. Do you happen to know what it is ?

It looks like it both cleans and imparts a rust resisant surface to the steel ?

When I was younger, I used some stuff called "naval jelly" which contains H3PO4 / phosphoric acid. I wonder if this is similar ?

What size tubing are you using ?

Nice work,

Harry

brucer
04-09-2012, 02:29 PM
are you planning on tig welding it?

HorridHenry
04-09-2012, 02:31 PM
The better brand in the UK is....
Liquid Engineering UK - Corro Dip (http://liquideng.co.uk/component/page,shop.browse/category_id,12/option,com_virtuemart/Itemid,1/)

HorridHenry
04-09-2012, 02:42 PM
Phosphoric acid - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Phosphoric_acid)

turpija
04-10-2012, 01:12 AM
Only that bottom table weight around 30kg..

There is phosporic acid in antikor, but i don't know what else

As i have co2 mig welder, that's what i'll weld if with
Need to figure out a strategy how to avoid warpage

Phife
04-10-2012, 11:43 AM
Are those rails supported or unsupported? what do you plan on machining with this machine?

HorridHenry
04-10-2012, 11:55 AM
Need to figure out a strategy how to avoid warpage

Corner tack then weld the top pieces,by the time you have finished the top welds they will have cooled, turn it over and do the bottom welds, then side welds.

Keeping the welds cool in between welds helps and you have done the right thing by chamfering the edges,only a qualified welder can reduce warpage in their experience,there will be some warpage but only slight if methodically welded. :)

PaulRowntree
04-10-2012, 12:11 PM
Keeping the welds cool in between welds helps and you have done the right thing by chamfering the edges,only a qualified welder can reduce warpage in their experience,there will be some warpage but only slight if methodically welded. :)

HH : How does the chamfer reduce warping?

HorridHenry
04-10-2012, 01:01 PM
HH : How does the chamfer reduce warping?

Did I say it will help reduce warpage? the job he's tackling needs to be clamped down solid if he's not going to lift one of the pieces slightly at one end to account for the metal cooling and contracting back into a straight plane.

The thing about welding is keeping the weld cool where/whenever possible and thats why its best to increment weld.

PaulRowntree
04-10-2012, 01:08 PM
Did I say it will help reduce warpage? the job he's tackling needs to be clamped down solid if he's not going to lift one of the pieces slightly at one end to account for the metal cooling and contracting back into a straight plane.

The thing about welding is keeping the weld cool where/whenever possible and thats why its best to increment weld.
OK, let me rephrase. What are the benefits of chamfering ?

turpija
04-10-2012, 03:40 PM
rails will be supported, but might deviate from original idea (which was to use some triangular spacers for achieve same distance over whole length of rail)
which might prove bad way to go if tubes are not flat enough

original design
http://i.imgur.com/tG4E3.jpg


and use bolts with few nuts to get correct height of both rails at what ever point needed ... will see how this goes ...

something like this
http://i.imgur.com/xr7TL.jpg

main purpose of machine is for plastics and possibly aluminum, but testing will prove actual capabilities ...

chamfer should enable weld to penetrate deeper if you have lower powered welder (like myself), and also help not to get too much of "bump" above line of tube ... so less grinding required if you wish to keep flat surface ...

yes, idea is to get everything as square and level as possible than carefully tack weld each tube at 3 or more spots, and if nothing is out of shape, start welding small beads as far as possible from each other, to keep it cool as possible

btw all tubes are 50x50x3 mm and metal sheets are 4mm thick, except few bigger ones that goes on Z axis which are 6mm

PaulRowntree
04-10-2012, 04:11 PM
chamfer should enable weld to penetrate deeper if you have lower powered welder (like myself), and also help not to get too much of "bump" above line of tube ... so less grinding required if you wish to keep flat surface ...


Thanks for the welding tip turpija!

TechGuy5002
04-11-2012, 06:47 PM
Better off going with commercial machined rails and using shimes underneath to control height. I think you end up wasting hours and hours trying to adjust your rails and still have issues causing flexing and inaccuracies.

With your new design you will need two nuts. If you apply a nut at the top of the square tube, there will be slack between bolt head and the nut permitting movement (up). In your original design the bolt head was applying force to the rail. You also introduce horizontal flex movement without the triangle wedges that would divert horizontal forces into tube frame.

louieatienza
04-11-2012, 10:32 PM
Another idea would be to use metal saddle washers, then you could just shim the washers.

However, I do have to agree that it might be easier to buy the supported rail, and more accurate as well...

turpija
04-12-2012, 09:32 AM
I am planing to use one nut underneath the square tube (actual bolt will be longer and head will serve only to tighten screw into rail), but i have same concern avout horizontal flex... Do you have any better idea hoe to keep adjustable height and add additional support ? I'm pretty much out of inspiration ... And yes, commercial supported rails are a better solution, and are also out of my budget ;)

http://i.imgur.com/t2YDa.jpg

turpija
04-15-2012, 05:47 AM
let's the welding begins !
or tacking actually ...

first, main frame
http://i.imgur.com/KZdj0.jpg

then, everything between
http://i.imgur.com/s7RnM.jpg
http://i.imgur.com/Lu8wV.jpg

and done
http://i.imgur.com/fz5dy.jpg

same technique used on those
http://i.imgur.com/6j1PB.jpg
http://i.imgur.com/OmUdO.jpg
http://i.imgur.com/Hj2l9.jpg

pile of metal starting to look like something
http://i.imgur.com/3EYfS.jpg

next on menu is a deep breath and fully welding all the pieces ...

RTP_Burnsville
04-21-2012, 04:56 PM
It looks like you are well on your way to having a nice machine....

Robert

rocketflier
04-22-2012, 05:35 PM
I am planing to use one nut underneath the square tube (actual bolt will be longer and head will serve only to tighten screw into rail), but i have same concern avout horizontal flex... Do you have any better idea hoe to keep adjustable height and add additional support ? I'm pretty much out of inspiration ... And yes, commercial supported rails are a better solution, and are also out of my budget ;)

http://i.imgur.com/t2YDa.jpgAre you filling these tubes? Otherwise how are you preventing the tubes from deforming from the forces applied when you tighten the nuts?

arizonavideo
04-23-2012, 02:14 AM
You don't have to fill them but if you offset them to one side you will have less flex.

CarveOne
04-23-2012, 06:55 AM
You can add no-cost supports inside the tubing by cutting and grinding scrap metal tubing to a length that just slips inside the square tubing. Put the bolt back through it and tighten as needed. Small diameter water pipe or electrical conduit works fine for this. Even hardwood dowel or squares of scrap wood with holes drilled through it will work.

HorridHenry
04-23-2012, 08:03 AM
One doesn't have to use any filling of the tube and a better securing can be had by using allen type bolts,you just drill a hole slightly oversize so that the stub of the bolt will go straight through the underneath of the metal and secured in the top section of the rail....like so...

HorridHenry
04-23-2012, 08:08 AM
The type of bolt I'm on about.

Phife
04-23-2012, 12:25 PM
You can add no-cost supports inside the tubing by cutting and grinding scrap metal tubing to a length that just slips inside the square tubing. Put the bolt back through it and tighten as needed. Small diameter water pipe or electrical conduit works fine for this. Even hardwood dowel or squares of scrap wood with holes drilled through it will work.

I tried this method on my machine that has through bolts on square steel tube, it didnt work, as the insides of the square tube are not consistent I had to keep grinding each collar until it fit. It was a huge pain, and if you had one in the center of the tube it was impossible to get it in there and aligned correctly. Also there is usually a thick weld on the inside of the tube that will also mess up that idea.

CarveOne
04-23-2012, 07:23 PM
I tried this method on my machine that has through bolts on square steel tube, it didnt work, as the insides of the square tube are not consistent I had to keep grinding each collar until it fit. It was a huge pain, and if you had one in the center of the tube it was impossible to get it in there and aligned correctly. Also there is usually a thick weld on the inside of the tube that will also mess up that idea.

It has worked well enough for me, and it wasn't so difficult. For the case where I had a weld bead in the way I cut a notch in the piece of water pipe to clear the bead. I don't fit the spacers so tight that they won't slide inside the square tubing. Any gap is minimal though. I can push the spacers to the center of my 12' tubing using a 6' piece of 3/4" square scrap wood until the spacer is seen in the pre-drilled holes. Start in the center and work outward as the spacers are inserted.

p00ky
04-23-2012, 07:36 PM
Couldn't you use a round piece of metal tube as a spacer inside the box section around the bolt (like a sheath). Or even just 50mmx50mm square washers top & bottem instead of small round ones.

rocketflier
04-23-2012, 07:59 PM
Yeah, anything inside to prevent it squishing down. Epoxy fill, hardwood blocking, spacers,...

Thick, wide washers are another method to transfer the force to the sides.

You can also buy (or make) steel spacers which fit through a larger hole in the bottom of the tube to push against the inside of the top of the tube. That way you don't have to try and slide each one into the tube and exactly line up the hole(s).

In looking at the photo below, the idea of a coupler nut might work as well. Drill the hole large enough for the coupler to rotate and simply tighten it. This of course assumes couplers are available longer than the tube thickness.

http://metalturnedparts.de/zimages/brass_spacers.jpg

turpija
05-08-2012, 05:19 PM
current progress ...

still heavily welding

http://i.imgur.com/lIU5V.jpg

a bit of grinding

http://i.imgur.com/fJOme.jpg

some paint

http://i.imgur.com/upfSW.jpg

and welding some more

http://i.imgur.com/luFwD.jpg

i think you got the pattern ;)

turpija
06-09-2012, 06:46 PM
so, here we go ...

all parts were smoothed a bit and painted

this will be a final color

http://i.imgur.com/e8iji.jpg

after some thought i've sprayed a poliureathane foam in all parts ... should work better than without, for vibration dampening, at least that's the theory

http://i.imgur.com/cFtzK.jpg

here is completed 4th driver ... what a masterpiece of soldering :D

http://i.imgur.com/Iv55j.jpg

and machined thread screws that should get the job done, at least until i get ballscrews sometime in far far future

http://i.imgur.com/msAY1.jpg

of course, a good machine needs a decent feets

http://i.imgur.com/RvMwN.jpg

still some welding and painting to do, but hopefully assembly is not so far from this point

nainino
06-09-2012, 09:05 PM
All I can say is WOW !

The finished parts look so good !

Can't wait to see your machine running.

turpija
08-02-2012, 09:55 AM
here is a bit of update

final welding and grinding of small parts
http://i.imgur.com/GQrue.jpg

preparing for paint
http://i.imgur.com/R64iX.jpg

the paint
http://i.imgur.com/OPJKp.jpg

turned out kinda sorta cool
http://i.imgur.com/vyRne.jpg


http://i.imgur.com/h5FcW.jpg
http://i.imgur.com/CeXVc.jpg

toneV8
08-02-2012, 01:22 PM
Koju boju si koristio, možeš li uslikati kanticu boje i u kojoj prodamnici si kupio.

Lijep pozdrav.

Falcon69
08-02-2012, 11:33 PM
hmm, i like that paint. I might do the same with mine. How many coats of clear coat did you put on?

But why paint the inside of the threads? Might make assembly just a little difficult. Next time, shove some tissue or something in the holes :P

Hmmm, I wonder if I can get the same texture type paint, but in powder coating.

turpija
08-03-2012, 08:17 AM
the paint is hammerite with effect (obvious ;)
supposedly should go directly on metal, even light rust ...

and there is no clear coat, just gray primer and hammerite

turpija
03-25-2014, 10:49 AM
it's been awhile since my last update, so let's fast forward to current state, shall we ?

start of assembly ...
http://i.imgur.com/VZjVbIF.jpg
http://i.imgur.com/S8me1Co.jpg
http://i.imgur.com/zYbHdpE.jpg
http://i.imgur.com/sOfSprM.jpg

and cnc made some actual first moves, but as it turnet out, screws were not too straight so whole machine started shaking and moving speed had to be very low ...
so, next logical step was to upgrade to ACME screws (as you call it i presume)
http://i.imgur.com/nt7B9We.jpg

redo all the work and hope for the best ...

http://i.imgur.com/6bGVKwx.jpg

some cutting of aluminum ... as it turns out, not such a great quality for machining, and with not such a great tool ... but hey, i call it progress ...

http://youtu.be/ZyhvQpGDMOU

and as it turns out, new screws were also not good enough, i suspect turning the ends were not accurate enough ... so, scrape em and start all over again ... but as i'm run out of hope for screws, and out of money to go for real solution - ball screws ... decision is to go another route ... belt drive !
currently there are some parts finished and looks promising but meanwhile you can enjoy this video ...
cutting aluminum of some greater quality (2000 series), and with much better endmill (single flute), and offcourse a decent motor to run it (not mine :(

turpija
03-25-2014, 10:51 AM
here is the video ...


http://www.youtube.com/watch?v=ZbvKO4pPxUk

wizard
03-27-2014, 06:00 AM
it's been awhile since my last update, so let's fast forward to current state, shall we ?

and cnc made some actual first moves, but as it turnet out, screws were not too straight so whole machine started shaking and moving speed had to be very low ...
so, next logical step was to upgrade to ACME screws (as you call it i presume)

ACME is the right term.




redo all the work and hope for the best ...

some cutting of aluminum ... as it turns out, not such a great quality for machining, and with not such a great tool ... but hey, i call it progress ...

You could work on speeds and feeds to improve quality and make use of a lube/coolant. For such a light machine it really doesn't look that bad.


and as it turns out, new screws were also not good enough, i suspect turning the ends were not accurate enough ... so, scrape em and start all over again ...

What was or is wrong with them? I'd try to get the ACME screws working properly before disposing of them.


but as i'm run out of hope for screws, and out of money to go for real solution - ball screws ... decision is to go another route ... belt drive !

A belt drive good enough to machine aluminum won't be cheap. You will need heavy timing belts with all the supporting hardware.


currently there are some parts finished and looks promising but meanwhile you can enjoy this video ...
cutting aluminum of some greater quality (2000 series), and with much better endmill (single flute), and offcourse a decent motor to run it (not mine :(

turpija
04-19-2014, 07:49 AM
did some work on belt drive ...

http://i.imgur.com/faD3JWz.jpg
http://i.imgur.com/sySSu9V.jpg
http://i.imgur.com/ekJYA7x.jpg
http://i.imgur.com/Buis31j.jpg

how it works at the moment


http://youtu.be/uhiDnIZB25g

10kg is whole Zaxis assembly, and apparently motor can't hold it while powered out ...

tahustvedt
04-19-2014, 08:39 AM
Nice work on the pulleys. You rmachine looks really strong.

I used a pneumatic cylinder and an 1,5L soda bottle expansion tank as a linear spring system on my Z. I can adjust the force by varying the pressure so that the stepper doesn't have to hold the weight. Mal Series 16mm Bore 200mm Stroke Pneumatic Cylinder | eBay (http://www.ebay.com/itm/MAL-Series-16mm-Bore-200mm-Stroke-Pneumatic-Cylinder-/190764024813?pt=AU_Business_Industrial_Industrial_Supply_MRO&hash=item2c6a6c03ed)

turpija
11-13-2014, 01:18 PM
here is some aluminum cutting with belt system

to be honest, i like the screw type more, but this will have to do for some time, because i don't want to pour more money in it ;)

and i have new cnc in construction phase, epoxy-granite is keyword, so it's not boring ;)


https://www.youtube.com/watch?v=QR7nuw1LVzw

klaas123
11-13-2014, 02:45 PM
Great job so far turpija, thanks for sharing!

shedbob
11-20-2014, 04:36 AM
Congratulations,nice machine.I enjoyed the pictures of progress.It looks to be strong,

Can you tell me the rail diameter you used.I could not find it anywhere in the thread,but may have missed it.

Do not let us just try to imagine your new cnc of epoxy-granite.Please start a new thread about it.

Faustoavel
01-27-2015, 02:51 AM
Hello. Compliments beautiful realization. Has been a while that I try to picture cnc iron on the internet, your cnc is the most beautiful.

turpija
01-27-2015, 04:57 AM
Congratulations,nice machine.I enjoyed the pictures of progress.It looks to be strong,

Can you tell me the rail diameter you used.I could not find it anywhere in the thread,but may have missed it.

Do not let us just try to imagine your new cnc of epoxy-granite.Please start a new thread about it.

rails are 20mm, but with diy supports, should go for real deal that support it whole length, that reversed "T" shape ... might upgrade in future

Faustoavel
03-07-2015, 10:00 PM
Hello. In a phopo you see the drawings for the realization of the cnc. You can share the instruction to build and asseble the cnc?
Thanks Fausto

turpija
02-26-2016, 07:15 AM
i've just recently play with high speed toolpaths and achieved great results

here is a video of milling steel with not so capable or rigid cnc

what i'm wondering is there an effective way to cut profile shapes (like the one here)

this particular one is made in rhinocam, and this machining operation is not originaly meant to work like this, so i have to draw 5mm wide rectangle (endmill is 4mm) and hope that it will start on right side, when i tryed to draw complex shape it started from middle, and if it's closed shape (just offset outside) it won't work at all ...

anyway, if you have experience with it, i would appreciate any help




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

turpija
02-26-2016, 07:16 AM
and just for comparasion, second video is with conventional milling (0.2mm DOC with multiple passes)
what's really interesting is temperature, with HSM i barely cooled the part (with air), and it works great ... i'm aware that actual coolant would help with tool life, but i'ts too messy, and for testing like this i can live with it


https://www.youtube.com/watch?v=RKjjjWG6LiI

Zekyx
03-01-2016, 06:09 AM
Which spindle are you using here? How come you don't employ your EG micro for this job?
Thanks, I'm enjoying your latest youtube videos, keep them coming ;)

turpija
03-02-2016, 04:35 AM
spindle is chinese 1.5kw aircooled

originally part was too big for small cnc, so i gave a shot on this one, and boy was i impressed ;)