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Re: Hacking the HP45

Posted: Sat Jul 18, 2020 8:03 am
by notsure
@nicolasgr

The HP45 cartridges are only good for about 1-2L of fluid before they start dropping nozzles. You won't be able to print a very large sand mold or core using them unless you have lots of them.

Re: Hacking the HP45

Posted: Sun Jul 19, 2020 6:05 pm
by nicolasgr
notsure wrote: Sat Jul 18, 2020 8:03 am @nicolasgr

The HP45 cartridges are only good for about 1-2L of fluid before they start dropping nozzles. You won't be able to print a very large sand mold or core using them unless you have lots of them.
Hi @notsure, thanks for the input, do you have any other jetting head in mind? I know the Xaar 128 can be an option, but I'm not really sure if can handle the resin binder.

Re: Hacking the HP45

Posted: Mon Jul 20, 2020 9:20 am
by Kaiqing
dear dragonator,
thanks for all your job in this website.
I am so interested in xaar128,Have you made any progress in this research?

Re: Hacking the HP45

Posted: Wed Jul 22, 2020 11:36 am
by visitsajjad
dragonator wrote: Thu Jul 16, 2020 5:31 am Hello

It has been a bit silent indeed. I myself have been rather busy the last months, and haven't gotten around posting as much as I wanted.

Reading all of it must have been quite a read. The HP45 page has grown quite a bit over time.

I have sent the datasheet by mail. I myself still haven't had much time to work with the C8855M controller, but the datasheet is fairly complete.

Yvo
I have got datasheet, Thanks for it. But C8855M is not available in market.
I considered using L6452, its still available in China market, but you design I think is more easy to follow. its easy to modify as per every one need.
I want to know if you have updated it with four TLC59213 ICs?
Regards,

Re: Hacking the HP45

Posted: Wed Jul 22, 2020 4:01 pm
by dragonator
I haven't. I still have 2 TLC's. The TLC59213 does not seem to be the bottleneck. If you fire all 14 primitives on one address, it just becomes unstable. I now fire 5-5-4 on every address and it works fine, though a bit slower. I still do not have a clue as to why I cannot fire all 14 primitives at the same time.

Re: Hacking the HP45

Posted: Thu Jul 23, 2020 4:01 pm
by notsure
@nicolasgr

The Xaar 128's can print a binder for sand or other powders. It just can't be aqueous since it is a shared wall design the fluids can not be conductive.

Re: Hacking the HP45

Posted: Sat Aug 01, 2020 1:52 pm
by maxt
notsure wrote: Thu Jul 23, 2020 4:01 pm The Xaar 128's can print a binder for sand or other powders. It just can't be aqueous since it is a shared wall design the fluids can not be conductive.
Hi notsure, since I'm familiar only witrh aqueous inks, I'll ask you a bit of opinion on solvent based inks. The intent is to use them with the XAAR128 (though we are in the wrong thread).

How dangerous are they ?

Would it be possible to use Acetone as the transparent ink, for powder printing (using the right type of plastic powder) without risking to blow up the whole lab ? How should it be diluted for this ?

thank you in advance!

Re: Hacking the HP45

Posted: Mon Aug 03, 2020 1:46 am
by notsure
We used to put solvent through the HP45's and the Lexmark TIJ. Mostly ethanol/methanol. What are trying to do with acetone and powdered plastics? Solvent weld plastic powders? Acetone has a pretty high vapor pressure so it will dry in the heads if left uncapped. I can supply you with UV curable binders for the Xaar 128. UV curable binders for the HP45 is also possible but like I said you get maybe 1-2L through them before they drop nozzles.

Re: Hacking the HP45

Posted: Thu Aug 06, 2020 11:07 am
by maxt
notsure wrote: Mon Aug 03, 2020 1:46 am We used to put solvent through the HP45's and the Lexmark TIJ. Mostly ethanol/methanol. What are trying to do with acetone and powdered plastics? Solvent weld plastic powders? Acetone has a pretty high vapor pressure so it will dry in the heads if left uncapped. I can supply you with UV curable binders for the Xaar 128. UV curable binders for the HP45 is also possible but like I said you get maybe 1-2L through them before they drop nozzles.
I do print gypsum powder with a mix of water/IPA (or ethanol). But the alcool only has the function to change the viscosity / surface tension of the liquid, the solvent for gypsum is the water.

My intent is to use a mix of acetone to print (the proper) plastic powder by melting it, and use solvent based color inks to render the colors.

But the question is still valid also for alcools, unless they are well diluted in water they are dangerous, maybe less than acetone but still... and since the XAAR128 does not accept water my concerns are still valid.

One more: I have a XAAR128 brochure of 3 years ago that was stating compatibility also with acqueous inks. Then the brochure was revised to exclude it once people on this forum started contacting XAAR about it. (Same thing happened with UV inks. There was a vendor listed on XAAR site, but after I contacted that vendor for info, and they replied "we don't carry it", that vendor's ink disappeared from the inks list...)

But still I'm wondering why the acqueous inks were on the brochure intially, and if there's any way to treat the inks so that they can be made low conductivity enough for this head.

Re: Hacking the HP45

Posted: Mon Aug 10, 2020 11:09 pm
by notsure
For using aqueous look at the older Epson piezo heads.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC507883/
This paper has all the drive specs.