I didn't realize raw materials for 3D printing required "dehydration" to improve results, but it does make sense!
Just like dry mounting a print, both the print and substrate should be dried (in the press) before mounting, else bubbles (from moisture) may occur after mounting.
Hopefully you allowed the print head to cool before using it? I would only have printed nozzle checks (if the HP has that feature) before challenging the print head with solid bars...
Can't argue with success, though!
...MALWARE!
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LA Awesome contains "some" Sodium Hydroxide, otherwise known as lye.
Very hash stuff! NEVER let that get near a print head.
I always final flush with distilled water, as the residual contaminants in de-ionized (softened) water are really unknown.
Water is strange stuff. It is REALLY...
Some use dishwashing soap (Fairy?) instead of Original Windex, since ammonia is under restrictions in some countries.
Distilled water is recommended as a final rinse (or two) to remove ANY hardness minerals from the cart.
"LA Awesome" is a very strong cleaner! It works well on outdoor cooking grills and similar really greasy deposits. On the bottle, it notes it is not recommended for glass. The recommended cleaner for Canon carts is Original Windex. I would NEVER let LA AWESOME (diluted or not) enter a print...
Be aware that that type of cart will still have a foreshortened life, since that type of print head has marginal cooling. NEVER let that style of cart run empty of ink, or will be certain to overheat the print head.
The ink itself is a major source providing cooling of the head.
I've replaced waste ink pads on my I960 and my MP730. It's like, one step beyond accessing the waste pump discharge tubing. Quite possible, but very tricky. Lot's of room for error...
I the timing encoder is clean, I have no solid answer. It certainly appears to occur during bi-directional printing due to the regular stepwise offsets. Perhaps the print head is "confused" about what nozzles to fire??
The alignment print "should" exhibit evidence of bi-directional offset...
IMO, the offsets are being generated during bi-directional printing, and not from paper feed issues. Higher quality paper selections typically force uni-directional printing.
That points right back to the timing strip. Just one drop of ink in the wrong place will be counted (or obscure) as an...