Why no South African posts?

[david.fick]

Hi my name is David, I am from Cradock in the East Cape.
I build my own cnc mill and i am totally hooked.
I like your chairs, great idea!

[drieslaas]

Update,

There always seem to be a pesky know it all radio control modeller type person around when you need them least . In an attempt to answer a question to one of these exalted beings, I embarked on the next little adventure:

I tried cutting 3mm balsa using a HSS 2mm slotdrill at 30000rpm. The cutter did not even realise the balsa was there. Very chuffed.
Also interesting was the route to reach the toolpaths. I hand-sketched the shapes, scanned to bmp, converted from raster to vector, did a very precursory clean-up of the dxf in draftsight, and imported into alibre for the cam work. Sounds complicated but took a few minutes because all the steps worked.

Have a look at draftsight by the way. It is from dassault systemes, a completely free update of the old dwg editor, and works magically for 2d stuff, which is something without which any cnc router operator cannot get along.

By the way, I also cut just into the surface of a 6082-t6 alum plate with the same cutter to see what it would do, and the results warrant further investigation. Nice diversion.

[rockhopper300]

Hello Jancu.
To answer your question. Yes, the next meeting should be on the sixth of October. I am sure all would like to know more about your laser cnc. If all goes well we should have the sceleton of a four axis cnc lathe at the meeting, and if time permits Prof Rudy would go through the setup of the stepper drives, calibration etc. Hope to see you there.
@Crixnix, I really like your idea of the sillouettes.
@Dries and Loffie. Hope to see you at the next meeting.

[fransfourie]

Hello guys

Im from pretoria-N and been Bitten by the CnC bug also ...hehe Ive been looking into building my own desktop cnc mill for a while now. Ive already ordered most of my parts and just waiting with baited breath for it to arrive. Any1 know how much it costs to laser cnc 25mm steel plate ? ^__^ Wana make it a very rigid & heavy machine as i wana mill alu. primarly & use it 2 build my larger cnc in time. ( 3 axis with a 4/5 axis attachment on table.) *Gulps*

Well also, 10 thumbs up for starting this S.A thread. Now i dont feel so alone anymore. Ill probably start a building thread asap when i got all my things. Btw...if you need ballscrew type shafts...try finding old elec. garage door rails. Got my self a 16mm 2.3m lenth in one and a 20mm in another ...lol alot cheaper to buy them new. got mine for free. Also ....build yourself some furnaces and melt down your own alu to cast & build your own machine. alot of fUn. Well im rambling here.....Its great to meet all of you and hope this thread will stay alive for years 2 come.

Have a Good day guys
Frans

[fransfourie]

Hello guys

Got most of my materials today So ill be starting my build on my 1.5m x 2m build 2morow.

Cant believe how expensive alu. is these days, my gantry, Z-axis & side supports is gona be made out of 20mm 6082 alu. & 76mm steel square tubing for the frame. Just wish they cutted my alu. abit more square .

Got 425 oz steppers, Gecko g540 for electronics & 20mm linears for all axis's.
Will order my 2.2kw spindle in 3 weeks or so....any1 maybe know where i can look for a Vfd 2.2kw ? One that doesnt cost the earth. lol

Just hope it will be rigid enough to handel milling of alu.

Btw...Any1 else here build there own CnC yet ?

[Quentinb]

@fransfourie

Welcome!

I've build one and am now starting a rebuild. The first machine was build using MDF and works pretty well. The alu I used for the rails with V-Groove bearings are wearing alot more than I would like and is causing some play on the gantry and Z-axis.

I am getting my new parts from Greg @ CNC Direct in JHB.

You must send some pics of your build!

Cheers
Q

[fransfourie]

@Quentinb

Thank you very much. Ill post some pictures soon. Just did a test fit "stacking it loose." the gantry + z-axis. I found out i need 2 get my alu. squared out more somehow >.< So ill first take all the parts 2 some 1 who could square it out to a Fine degree, before i continue. wana do it once. hehe As the saying goes....Measure twice, cut once.

Mind uploading pics of your builds ? ^__^. Might give me some extra inspirations.

BTW....why not import some 20mm linear round shaft blocks into the country?
Cost me aroun R1400 delivered for 8 x 20mm linear sliding blocks. Bought some high grade 20mm round shaft (R370 for 6m) and it floats like a butter-fly..Stings like a bee. lol

If you dont mind me asking, you maybe know where i can get a 2.2kw Vfd locally? Or what makes are supported in south africa. Would be much appriciated.

Well...Nice meeting you

Cheerz

[Quentinb]

Where did you get the round bar/shaft from?

I have thought about using it, but worry that with a big machine it would deflect to much over the length. I want to build a 2.5m x 1.5 machine and wanted to use the round shaft. I also thought about the C style bearings with the mounted round shaft but the whole unit makes it very "high" in terms of the shaft and mounting + the bearing added to it.

my current machine....p

[fransfourie]

Heya m8

a Nice machine you got there

I got the round bar at alert steel. It is sitting abit high...2 sec..measering fast...+\- 60mm from top of the block to the bottom of the support bar for the shaft.

The linear block dimensions are H:37.6mm L:50mm W: 49mm (C - style )

Ill be taking a 20mm flat bar(+\-50mm wide) and mill 2 sides on top down by 5mm(10mm wide centre will be kept at 20mm then take a 20mm ballnose endmill to put a radias on the extruded piece for the rail to lay in. dont know yet if ill get it co2'ed or screw it to the plate. this should keep it nice and strait. Well once i do it, ill let you know if it works. Cant see why it wont.
But first im trying to find some1 in pretoria that can square out my alu. with a waterjet cnc.
Ive added a drawing to show what i mean.

Guess you can also make small shaft supports by drilling into say a block of alu with a 20mm dia drill bit & then sawing it in half then space it through the whole length of the shaft for support. example you have a 1m length of shaft. make support blocks for every 200 mm. Draw a line on your gantry with a vinear, drill & tap? them for you support blocks. Should work also.

Btw...What controllor you using ? stepper sizes etc. ?

Well speak to you soon again

[MickJack]

Hi Quentinb
Where did you get the V-groove bearings from?
What size are they and how much did they cost.
I cannot find a supplier anywhere in Durban for them!
Cheers
Mike

[fransfourie]

Heya jack

What size table you building ?

Got my alu. squared out ) engineering square, strait edge + wood router on a table does wonders ...hehe

If i get time ill drill and tap my z-axis 2morow & upload a pic of it

Quentinb.....Because of you i changed my table also to a 1.5 x 2.5 table xD
Need to go buy 76x76 square tubing this week and guess ill start building the framework the weekend.
Any1 know of a place in pretoria that sells rack & pinions ? very fine teeth??

[Quentinb]

@MickJack

I imported the bearings from the US. I tried all the bearing places locally and nobody could help! Have a look on buildyourcnc.com for some parts and ideas. If you like, I can assist you as I have a contact there - depends how many you need, I have some spare though...

@fransfourie

"What controllor you using ? stepper sizes etc. ?"
I am using the motor and drivers from the above site. I bought a "Combo" that has all the required goodies to make it work. then I am using Mach3 for the control side of things along with Cut2D for the toolpathing.