NickJ

9 hours ago, BlownCorona said:

just a cheap parallel port card and the stepper drivers that it came with. the para port card is nothing but patching the specific output wires from the DB24 port to the stepper drivers and the limit switches, z probe and e stop but through opto isolators for safety and with the addition of a couple of controllable relays. it relays on the computer itself to generate steps which so far seems to work fine. a large table such as yours may not be so gravy 

Oh thats pretty simple! will get LCNC running really fast, all the little details in linux will make the machine really useable, excited for ya! I've just got my head around the PLC side of it, just mulling over how to re do the wiring then I can start looking at getting toolchange working, toolprobe etc etc. Wiring sucks cos once I move that its past the point of no return, up to now i've just been chipping away on another config file.

Yeah parallel breakout won't work with my machine cos closed loop servo drives, needs the Mesa board to do the realtime movement control, which kinda sucks cos I pulled a stack of breakout boards from the previous controller!

3 hours ago, rossnzwpi said:

On the topic of correct surface prep.... I have a 1960s engine with magnesium castings that I want to clean (blast?) and have an anti corrosion surface treatment applied. Originally this was a DOW chemicals dichromate passivation that is specific to magnesium castings. Does anyone know a way to do this or a company that does this in Auckland? Datlow - your comment about not dipping Ferrari magnesium wheels in acid wash comes to mind.

When I was doing aviation stuff with Mg, SafeAir/Airbus in Blenheim were the only people in NZ doing it, and somewhat difficult to get a job in, might be worth getting in touch with the warbird guys?

12 hours ago, BlownCorona said:

im about 90% done with setting up a full linuxcnc controller on a dedicated box. but just a cheap breakout board instead of fancy mesa cards like yours, my cutting speed and small table is forgiving enough to run happy within its limitations it seems. i just need to physically install limit switches so homing works and setup auto z probe and then actually learn how to operate the thing properly. 

 

How are you setting it up without the Mesa board? Keen to see another way of putting it together!

yep, there is still a waveform on the +12V side, but the lead that is to the points/trigger should have the largest wave the relay is looking for

Also those are very nifty relays that I really should have on a few cars....

Have you tried a different coil wire? Might not be getting the signal off the ground wire and expecting the opposite polarity?

What controller are you running? Hopefully a tool table in there so XYZ offsets are simple to implement?

Have dragknife blades on the way, plan to make a small holder that mounts in one of the 8mm subspindle chucks. If I get it right both the knife and pen will be just a tool change call away.

Wonder if I can find some 50mm or less markers on Ali.... 

22 minutes ago, BlownCorona said:

I want to do that but with an Er11 chuck. Maybe the inside of a gel pen?? 

Ideally I wouldn't have it in a tool holder but couldn't find any easy locations on my Z to mount it, bit lol for how big the machine is! Having 19mm collets kinda made the decision for me as a quick and easy to get running. 

Cos ER11 is tiny, could you mount it with P clips on the side of the spindle?

Good excuse to put some form of heat exchanger in the system? A car AC condensor will be rated to ~250psi which would be an easy addition.

Guess would be original was 1-1/4" tube?

A std polymer hose won't be up to the temps unless it has some form of reinforcement, depending on the application, service temp can really drop the rating too.
Almost any metallic tubing at that size range will be good for 100Bar and not care about temp. Metallic connection will also give at least some effort of dumping heat before the receiver, comes down to access to suitable bending gear and compression fittings can get spendy over 1"
If you go for steel, make sure the bends are in such a way so that thermal expansion doesn't try to pull them apart, a big elbow usually does the trick.

With what Azzurro says, if its old and someone else has messed with it, you're most likely on your own for troubleshooting unless the installer left detailed notes of how they altered the system (even then as built drawings are comically imperfect) go back to first principals and check fuses, earths, connections, switches and then poke around with a meter to confirm stuff is doing as it should at each junction, I usually note this on the white board as what is good, and what isn't good.

If something worked then there was a change and it doesn't work, thats the smoking gun 99.99% of the time.

Worth keeping in mind to locate test points is indicator relays often rely on a certain resistance to work, anything added to this circuit can play funny buggers confusing the situation.

I have a selection of clippy leads and dummy connectors that I use to isolate circuits for trouble shooting, it sucks and often needs a few brews before the issue is properly diagnosed and treated, isolating is the best way to minimise false positives that are so common in 12V systems.

He said it, Wednesday next week, spitfire square, print the flyers!

Sounds like only Italian cars can, well done!

yep, keen as, weekday evening i'm guessing?

Pity the access to cow stream hot pools is closed for winter, 4wd camping up there would be good fun and no one about to complain about noise

16 minutes ago, rusty360 said:

I have a real good guy in pukekohe that knows his shit, maybe you can send him a couple of pics if you have no luck down there.

Cheers! I'm gunna hit up Deviceco in the morning, looks like the kind of people I need to ask locally, will keep you posted.

2 minutes ago, waspman said:

Not surprised that you had issues with SIL, now owned by Motion and all the decent staff left, another one to try is Deviceco Pneumatics if they can't help they may be able to point you in the right direction.

Ahh, yeah was wondering that, the guys in the old building here were super knowledgeable and had got me out of trouble many times, the recommendations different staff gave today didn't seem to weigh up to the product knowledge I have been used to.

Thats got me closer on the internets!
Could even adapt a rod seal to suit....

Bit of help required with the cnc router, have an airleak that hopefully someone here can help with locating the seals?

The spindle has 3 coarse height positions set by air rams, to fed these instead of flexible hose they have hardline working in a sealed bush that has perished

This is the entire moving spindle assembly, red line is where the tool sits (no holder currently in place) with the offending air feed circled in blue.

The travel is about 50mm in total inline with the tool

This is the air feed removed, silver tube is hollow, black nut contains the seal I need

Original seal is ~10.6mm OD, shaft is 6.00mm x about 10mm long, has a brass outer and the rubber inner has perished and with 80psi behind it, shat out everywhere.

Anyone have a name for this type of seal? Went to Seal Innovations today and had them stumped, same with a pneumatics supplier.

My workshop docs for the machine don't list them with a part number to search either.

Also open to modifying the nut to take something more 'normal' or obtainable.

Unfortunately there is not enough room to just put an air fitting direct and let flexible hose do its job.

On 17/03/2024 at 21:09, yoeddynz said:

Peak Engineering textbook and probably one of the best books ever written

Shrink fit the axles is a brilliant idea, love it!

55 minutes ago, dmulally said:

I'm using mine as a trolley too. Does this work for you?

 

Hell yes!

Yours has the spot timers which mine doesn't but the article number has now given the right search term to finally get a wiring diagram, epic!

Thanks heaps!

3 minutes ago, dmulally said:

Ended up getting the floor model which has been superseded for a hefty discount. I gave it a quick whirl and the welds come out very smooth indeed. I have a bit of panel work to do on some thin stuff so I'll see how it likes that. Thanks for the hot tip, gents. 

Oooh, I have the same Cebora,  any chance the front panel writing is still visible, wouldn't be able to put up a picture if it is? Mine is all worn off.

Good enough machine but now just a heavy trolley for the tig

Spotted just outside Zurich, no doubt proud as punch of their life choices in a land where fuel is beyond $4/l 

Is the crank offset to the bores? Could imagine that might be niggly.

Thats pretty much what i'm looking at so that I don't occupy so much space, a hoist pretty much guarantees only space for one car over two bays.

Having to bolt it down to use is holding me back, something more like a pallet trolley would be better.