Injection moulder

[neftaly]

I recently acquired a broken BOY 15 Injection Moulding machine. It's about 40 years old and needs some TLC. Hoses etc are mostly kaput and the electronics are toast. Motors, solenoids and hydraulics are all fine. Giving myself 6-12 months on this one





Loaded it on a digger trailer with a forklift. Unloaded it by hand with some muscle and a few bits of steel pipe



Have been cleaning out gobs of hydraulic oil sludge, baked-on plastic and other accumulated crud



Stripped out all the antique electronics, will be replacing them with some nice new modern technology.



I plan on using one of these things, it's a bit like a combo PLC/HMI (running on a Cortex M3). Has Ethernet, a touch screen, plenty of IO etc.

[desertT1]

I don't envy the project, but it'll be worth it in the end.

[Simon]

Now that looks like a very difficult, but interesting project! Do you have experience with these kinds of machines? or are you learning as you go?

[Unfated33]

If it helps any, I think these are the software references and support for the HMI: https://www.hmisource.com/otasuke/

[neftaly]

Learning as I go (have a few books and stuff to help), think I have the machine mostly figured out though.
Thanks Unfated but it's an embedded system and not a HMI, so I'll program it with ARMs "Keil" SDK.

[FLounder]

Years ago my old company dabbled in injection molding for making keypads for cell phones. I wish I had learned more about the equipment when it was there. Sadly it has all been sold off and the facility closed down. It did seem like a really neat process.

[neftaly]

I've pretty much finished cleaning the outside and have sorted out the housing for the new control electronics. There is still a bit of baked-on plastic around the nozzle area, I'll have a go at it with solvents then heat then a chisel.

Charted out all the electronic controls (solenoids, switches, heaters and sensors) which was the biggest perceived hurdle. Turned out to be super easy, the whole project is a whole lot less complicated than I originally thought.

I took out a wall to extend my shed and put double doors in so that I could fit it inside, will move it tomorrow. On monday I'll put feet on it and take it off the pallet.

Over this month I'll finish cleaning out the oil tank. I have to buy a barrel of 68 hydraulic oil (cheaper to buy 200l than 100l), the linear encoder, a couple of 3-phase relays, new wire, pressure transducers (optional), water coolant mainfold, power supplies, and some raw plastic + supplies for the mould tool. I'll replace the hydraulic hoses soonish. Might also replace the heaters and thermocouples while I'm at it.

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Most of the limit switches will be replaced with a single linear encoder (or maybe 2). I'll have one switch on the safety cover, possibly two on the screw and possibly one to detect when to switch injection pressures.

Heaters and thermocouples are really simple, it's obvious which are which just by looking at the screw assy. I think I'll wire them to 2-3 thermostats initially and integrate into the controller later.

There are a couple of pressure gauges which I'd like to replace with 40mpa pressure transducers. That isn't urgent though.

Pressure adjustment on regs is with knobs. No reason not to leave them as-is.

Solenoids:

S1 - Close mould [high pressure clamp adjust]
S2 - Lock mould [high pressure clamp adjust]

S3 - Open injection nozzle
S4 - Injection unit (screw?) forward
S5 - Injection unit (screw?) backward

S6 - Mould open [high or low pressure clamp adjust]

S15 - Ejector
S16 - Decompression (hydraulic screw retraction... this was in German, I think it's referring to the ejector - will have to see)

S17 - Mould close [low pressure clamp adjust]

S18 - Injection pressure adjust (toggles between main and secondary injection pressure)

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S1 closes the clamp with more speed/force than S17. Whichever you use depends on the amount of clamp pressure you want.

[Simon]

That's exciting. Sounds like a lot of work but you are getting close. Felt the same way when I went through and got my VF2 all set up and running, but yours is a far bigger project

[neftaly]

Moved it inside, attached some feet and got it off the pallet with a crowbar and a couple of jacks.

TI just released another Launchpad, the Hurcules RM42, which I'll be using instead.

I think I can just use a limit switch on the die side, so hopefully will only need a single scale. Can now also use a digital quad encoder instead of an analog scale which is great.

[neftaly]

Worked out the operation cycle, did a flowchart. Took off the heater jackets, am organizing some new ones. Almost have the nozzle heater off, there's a lot of baked-on plastic around it that I've been slowly chipping away at. The 8 hex bolts around the nozzle had almost completely seized up (combination of plastic and corrosion), but I eventually got them off OK. Took apart one of the solenoids (and the regulator it was attached to), cleaned it thoroughly, replaced the cable, replaced the O-rings, put a new seal around the manifold and lubed it. Only 9 left to go... this'll take a while :B