Titivating a Wire EDM Machine

Gallery, Projects and General > Project Logs

<< < (33/35) > >>

awemawson:
So this little mini projectette is almost done.

There is a tapered sleeve that the wire actually winds on that I need to make. It has a parallel bore but a steeply tapered outer diameter so that it can be pushed out of the wound wire easily to recover it for re-use. It is what sets the width of the spool, the screwy bits clamping it against the cheeks. The original has been broken into four pieces and bound together with tape! Two of them to make.

And also the spool is driven by a sliding peg that sits in a slot in the hub - there are four slots on each side of the spools, but only one is actually used. So that's another little task for when the glue has hardened - the makers claim 24 hours.

awemawson:
So this morning I made the two tapered rings. These go on the hubs of the spools, the idea being, when you want to remove the scrap brass wire, the ring comes off with the wire and as it is tapered will then push out of the wire easily. Remains to be seen if this theory works - the original was always a pain to remove, but it had been covered in masking tape to hold it together. I increased the taper to 8 degrees from the original 5 degrees to help removal, and also made the rings a couple of mm thicker so hopefully they wont suffer the same cracking fate as the original.

I only just had enough of the 180 mm x 70 mm polycarbonate rod left to make them - the chucking bit was really rather short :bugeye: But it worked :ddb:

awemawson:
This afternoon I've milled the drive slots and assembled the spools and installed one on the machine - seems to work which is just as well after all this faffing about :ddb:

So I think, barring accidents that just about wraps up the mechanical side of things.

awemawson:
Next job is to upgrade the memory. As previously stated this (and other Fanuc 6 controlled machines) uses 'Bubble Memory'. When I got the machine is came equpped with a 16K byte memory which (rather charmingly) they refer to in the manual as 40 metres of paper tape equivalent.

I got my sticky fingers on a 128K memory board shortly after I got the machine and installed it. The process is a bit complicated for two reasons. Firstly the bubble memory contains all the machine parameters including those needed to drive the RS232 interface, and it's that interface through which you need to re-load all the parameters. A bit of a chicken and egg situation! This is circumvented by manually inputting just the bare comms port settings and then re-loading. But before you do this you have to manually load all the 'Defect Loops'. When these memories were made not all the internals were perfect, and any defects are noted on a table on the card.

But now another bubble memory drifted into sight recently (ebay in the USA) - this time a whopping 512K byte or 1280 meters of paper tape :lol: This is the maximum memory size for this machine. It arrived yesterday so I must revise the procedure, take numerous back up copies of parameters, cutting data, and ball screw error corrections, and go through the process again. At least this time all the data is retained in the memory that I remove, as bubble memory is 'non volatile' rather like core store used to be. So in a worst case senario I can re-install the original and start again.

awemawson:
Well to cut a long story short - no, the replacement Bubble Memory didn't work. I'm sure that the seller sold it in good faith but it fails to clear when told to. Currently in transit back to Knoxville, Tennessee curtisy of the ebay returns system, foc to me, and paypal are arranging a refund.

However I sourced a second one here in the UK, and that worked first time and is in and running :thumbup:

Navigation

 Message Index

Go to full version