Thread: New Aussie Build

Well, things are slow (mainly due to house stuff) and im still trying to find some cheap metal supplies but am thinking about changing the design mainly because it would be cheaper to use aluminum bar rather than aluminum plate as it seems the local shops will charge more for the plate...alot more. Still haven't organised how im going to machine it but i'll sort that out soon. Worst thing happens, if i need a temporary solution i will just machine some 10mm perspex, rid the idle pulley and try the design out by just buying new belts for the pulleys.

Good news is the last of the rack should be here tomorrow and im ordering the last pulleys tomorrow also. It also looks like i will have enough money this month to buy some drives for the electronics. Thinking about gecko 203v but am also thinking about the g540(or g251). Just not sure if nema 23 are going to be strong enough for this machine to make it do what i want. Eventually i would like to run the machine from a grex but that is definately a while off.

Daniel
P.S this is really just a ramble since im hoping it might get my *** into gear and do some more work on the machine. Also it might remind me to take photos. lol.

Yep, need some pictures Daniel.

Must admit you do get flat spots in the build where you loose enthuisiam or funds or time are tight.

Rod,

I definately agree with you there. One of those three or you end up spending too much time thinking about a new machine a new thing to make or at least something cnc related. lol.

Just to try and remind myself i have put new batteries in the camera and put it in the middle of the desk. So hopefully i will remember to take some photos of the extrusion and the rack and pinion that arrived last night and the pulleys. If i take photos it should get me more motivated.

Daniel

Hey Rod,

Got one for ya. Went home, my reminder on the mobile went off and i took some photos...guess what. In the haste of getting to work and remembering a few extras i needed today, i forgot to take the memory stick out. So there is a new reminder to take it in the morning.

So just one more day to wait for photos...hopefully i wont forget.

Daniel
P.S Man i miss broadband, it would have been up last night, but it is hard to post pics with dial up. lol

Quick Vacuum Question,

I can see on another thread on the zone that there are some vacuum posts flying around. Sorry to post outside with similar question but it seems busy there. Greg linked to an ebay refrigerator vacuum. Just curious how would that do on a large machine like mine(i would have a reserve tank). Alot of my stuff would still be clamped but i was curious how much one of them would hold. I do a bit of foam which it would come in handy for but also eventually want a proper vacuum for most things.

What does everyone use or does anyone have comments on the refridgerator vacuums one ebay? Would i be better of converting a compressor?

Daneil

Well its been a while coming but i have some photos of some of the parts. Good news today was that my t nuts have finally arrived and are being express posted out to me so i should have the gantry nearly complete by the weekend. Just need to sort out what i will do for the rack.

What do people recommend for the linear rails.... one on the front surface and one on the top or should i just run 2 rails on the front?

Anyway, i have a lot to look forward to this week really excited that this machine is nearing the end. The last pulley reduction set will be ordered this week and i will have to sort out what to do for the plates.

Daniel
P.S Sorry for the bad quality photos

Originally Posted by twistedfuse

What do people recommend for the linear rails.... one on the front surface and one on the top or should i just run 2 rails on the front?

Going from what Rod has told me and others is to protect them.

I was told to put 1 up top and 1 behind but I have round rails so 1 up top and 1 down bottom might be better suited for the square rails.


Is that 160x80 alu?


Apart from that, looking good.

I would still go 1 on top and 1 behind at the bottom of your 'beam'. I think Rod posted some recent photos showing how he did it. The top one would take the majority of the down loading and the one at the back just keeps everything steady. Am not sure where I posted it, but I am sure i put up a photo showing how I slipped in some plastic tongue stripping into the t slots that would be open to gather dust and swarf. I have been milling some bits on my widgitmaster and even though I am only using a 3mm end mill, the alum swarf goes everywhere!!

All the best with the rest of your build.

BTW what gearing ratio are you using?

Cheers,

Alan

Daniel

For what it is worth my opinion is that the rails would be fine on the front and/or top.

That is where mine are and I have never wished they were elsewhere.

The wipers on THK style linear bearings work very well and sawdust is not as much of an issue as it might be on round rail or other styles.

Just make sure you use the little plastic plugs they provide to clip into the bolt holes. Not much good without them.

Greg

Thanks for the replies guys, im getting excited since everything seems to be going well atm and finally coming together. New pulleys will be ordered in the next few hours (as long as i don't get sidetracked) and i found a local supplier of aluminum flat bar 100mm wide x 6 or 10mm thick. I Will most likely modify the design of the reduction plates to use the 100 wide stuff and not the 160mm since it will require less machining and i should be able to do it myself(or at least it wont take long on a proper machine). As for the rails, i agree since i spent some time thinking about it last night and realised i overlooked something. To make the build simpler for everything to connect together i realised that using the rail on the top would allow me to have the option to follow gregs design and connect the reduction gear assembly to the plate mounted to the bearings.

Chris, the extrusion is actually imperial as i would have had to wait for the 160 x 80 so instead i got a discount on this length of 3" x 6". It doesn't change the design too much and according to the deisgn calcs it has less deflection (not that there was much on the other beam anyway). It just means i need to use imperial dimensions to set my holes but it easily converted.

Zoot, its funny when i saw your posts about filling in the gaps in the extrusion i laughed because i was actually browsing the catalogue the night before and had saw the gap fillers and thought i would look into them but forgot until i saw your post. They seem cheap, so dont see why i shouldn't do it and it looks alot cleaner. The back will probably be covered in perspex and have the name of the cnc engraved on it (maybe some of that flouro perspexwould look good. Maybe i should add some fancy led lights to it too...lol) but the rest will be filled in with these tongues. As for the reduction puleys, it is a 4:1 recution. The large pulley is 48 tooth, the small one is 12 tooth all at5 non slip timing belts and pulleys. The pinion for the rack is 20 tooth. In regards to comments before about the shaft it will be 10/12mm since i can easily get enough meat to tap the grub screw into the pinion.

Greg, your opinion is worth every penny. I almost forgot about those plugs (sitting in the box on the cnc frame atm) since i haven't been out to do any work on it lately. Will have to make time this friday or this weekend. Its seems hard since its not close by...just means i have something else to look forward to when the house in complete.

Daniel

Just wondering,

I have sorted most things on the reduction pulley assembly but wanted to make sure. Would there be any issues with a 5mm or 6mm thick bearing or should i use a 10mm thick bearing. This will determine if i buy the 10mm plate or 6mm plate.

Daniel

Hey Guys,

Some more progress made last night. I finally got out and tapped the ends of the gantry for the M8 bolts, now all i need is the gantry sides. Let me just say the next purchase i will do for this machine will be a tapping head since it was a pain in the ***. Contemplating getting some laser cut steel for sides (aluminum doesn't work too good on the laser machines) or finding someone to cut the profile of the sides on their bandsaw.

I also got around to sanding back and painting the under-braces which i will attach next time i go out to the machine. That way i can organise the table top wood and start work on the vertical clamping system im looking at for dovetails and end drilling/tapping.

I'm holding back from assembling the gantry mainly so the rails won't rust up where i've touched it like the others did. I bought the aluminum strap to attach the rack to the back of the gantry and will work on that. I also bought some 100 x 10 aluminum flat bar for the reduction drives. Now i just need to figure out if i can get someone else to do the machining or wether i'll try with my machine. Either way i redesigned it to use standard 6001 bearings which will give me the 12mm shaft as recommended. Hopefully i can push on and get these complete over the next week.

Anyway, its a minor progress but its giving me more hope that this thing will be completed soon. Can't wait to see it in action.

Daniel

Daniel

Where are you at with the motor mounts? Want to send me a DXF?

Greg

Hey Greg,

Not getting anywhere fast so i have emailed you with the files.

Daniel