Closeup of the top plug assembled.

The floats are just a hollowed out piece of rod and a cap. It's a frosty texture because I turned it down slightly on the lathe so that it's a very loose fit inside the reservoir tube. Ink and air bubbles have to be able to get around it.

Assembled float. it has to be hollow because plexiglas is denser than the ink.

The reservoir tube body, bottom cap, threaded barb fitting, and gasket. The gasket is a soft silicone (Shore 10A; this might be too soft in practice) with an acrylic adhesive backing rated for submersion.

Fully assembled ink reservoir, pending testing! (Well, OK, in this pic it's also pending final bonding)

OK, enough for one night again. Next up, a nice stand to put it all in.

Getting back to the Bondit B45 epoxy after 48 hours of cure:

1) It cures into a very flexible state. It is surprisingly soft... the docs say the final cure is shore 80A and that even seems a little harder than it is (I was guessing shore 50A).

2) Peel test off of a perfectly smooth, clean PP surface was disappointing. Although it clearly adhered, it peeled off rather easily-- about as easily as scotch tape. This is obviously not structural.

3) Peel test off of an abraded surface (which is more realistic) was more encouraging. Here the bond was more structural.

4) The test barbs did not leak and destructive testing showed the bond in the threads difficult to break.

So in the end... still not a miracle glue, but probably good enough and long-lasting enough. I at least think I trust it in the context of this system. Any unfortunate failures will be catalogued and reported ;-)

It occurs to me that although cyanoacrylate glues are unsuitable because they're water soluable, many expoxies weaken or dissolve in some alcohols (depends which), and all these inks do have an alcohol component. I'll have to test that too...

Hmm... from a practicality point of view that's an interesting design although the long tube means it'll be difficult to locate and incredibly easy to knock over... That said, presumably a good way to stop air getting into an HP system which is the whole point.

Unfortunate about the glue and on reflection sounds a lot like an epoxy I already have access to here, so I think I'll eskew the purchase for now until you've had a chance to really test it long term...


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Printers: (Canon) MP500/830, MX700, iP4000/4200/4300/4500/5200, iX4000(A3) (Epson) C84/86, D88, CX6600, R285/800/1900 (HP) K550, K850, K5400, L7680

Martin wrote:

Hmm... from a practicality point of view that's an interesting design although the long tube means it'll be difficult to locate and incredibly easy to knock over... That said, presumably a good way to stop air getting into an HP system which is the whole point.

It could just as easily be shorter/fatter tubes. I purposely went for long/skinny and plan to make a mount/stand that slots them onto the back of the printers in a way that's well attached, and the printers are all backed right against walls, so there's nowhere for the whole shebang to get knocked to (the printers themselves are a good 35+ lbs). Maybe a good idea, maybe not, but certainly a design specific to this setup and location. I was sort of thinking 'control rods' when I specced it out :-)

But you're right that it's probably not what anyone else wants (and I may decide it was a bad idea later too).

Martin wrote:

Unfortunate about the glue and on reflection sounds a lot like an epoxy I already have access to here, so I think I'll eskew the purchase for now until you've had a chance to really test it long term...

Yeah, I feel the same way: disappointed. I'm not sure what it offers over a standard flexible marine epoxy at $8 per 50ml. I'm going to do a more controlled test directly comparing to marine epoxy, two-part silicone, and the PP superglue someone else mentioned. But I'm pretty sure at this point it was just a waste of money. Not bad, just not better than the cheaper stuff. We'll see in few days.

Monty

xiphmont wrote:

It could just as easily be shorter/fatter tubes. I purposely went for long/skinny and plan to make a mount/stand that slots them onto the back of the printers in a way that's well attached, and the printers are all backed right against walls, so there's nowhere for the whole shebang to get knocked to (the printers themselves are a good 35+ lbs). Maybe a good idea, maybe not, but certainly a design specific to this setup and location. I was sort of thinking 'control rods' when I specced it out

If it's any consolation I have to stop myself assuming that everyone has shelves on rails with a space at the back so that tubing and other things can be dropped down behind. I have this great waste ink kit design which would suit perfectly but it just wouldn't suit more than about 1 in 100 people probably...

I see your point re: the layout you have there though... and heck if it's stupid and works it ain't stupid

Quote:

I'm going to do a more controlled test directly comparing to marine epoxy, two-part silicone, and the PP superglue someone else mentioned. But I'm pretty sure at this point it was just a waste of money. Not bad, just not better than the cheaper stuff. We'll see in few days.

I'll be interested to see how that works out too... I'm thinking that a little roughing up of the plastic is in order on any bonds, especially with epoxy but I'm a bit like you... I prefer clean


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Printers: (Canon) MP500/830, MX700, iP4000/4200/4300/4500/5200, iX4000(A3) (Epson) C84/86, D88, CX6600, R285/800/1900 (HP) K550, K850, K5400, L7680

Sorry, had to put down the project for a few days, but I'm back.

I'd mentioned making a stand that couldn't be knocked over-- here's the pieces cut out before assembly and finishing. I'm using MDF, nothing fancy.