Print quality question

[JeffB]

I tried DA a bunch of times and it just seems to work faster. That slimy resin turns bone dry quick. In fact I just saw Menard's has a gallon of DA for $15. That is now cheaper than 4 quarts of 91% from Walmart. But there is nothing wrong with 91%.

DA is definitely faster and seems to clean the prints better...  No doubt about it.  Cheaper too, by a lot. 

I'm considering doing the first cleaning (in my workshop) with IPA, then do a second rinse with DA up in the garage (where I blow my prints dry).  This has the effect of minimizing the fumes (in the workshop) but ensuring complete cleaning of the prints.  Plus using DA in the open air of the garage (doors open) is less of an issue for exposure (to the fumes at least).

Just have to get my modeling mojo back and put all this "considering" to use. 

JB

[timwatson]

Yes like @JeffB says it's much more important to wear gloves when cleaning with DA. It acts like a transport that carries anything in it into the skin. I wear 7mil gloves when cleaning with it. Also it goes without saying don't drink it despite it being alcohol. I had someone on FB try to tell me it would cause blindness without looking and seeing that it is only when ingested - that it does that.

I switched to DA a while back and noticed how much better it cleans resin right off the bat...  Great for cleaning resin and it was available when IPA got scarce at the start of the Pandemic.

Just keep in mind a few things...  First, DA is much more flammable than IPA.  If your basement workshop is in the same space as your furnace (as is mine), it's advisable that you clean your prints with DA somewhere else (especially if it's winter and the furnace cycles regularly).  Second, it's quite a bit more toxic than IPA.  Read up on it prior to using it and make the decision to switch (or not) once you've educated yourself on the health risks.

While it is markedly better at cleaning prints of excess resin, I switched back to IPA now that it's available again.  I'm not overly paranoid about using chemicals (I use Acetone pretty regularly), I wanted to limit exposure to DA based on what I'd read about it. 

JB

[GaryHinshaw]

I confess that I'm not sure what the issue is with Joe's print.  Is the light powder on the flat spalling off the printed part?

In any event, my cleaning regimen involves no scrubbing, as my parts tend to be small and intricate:

* 1 swish in old IPA - I just take the entire build plate and swish it around, by hand, in the vat for ~20-30 seconds.
* Repeat in a 2nd vat of clean(er) IPA.
* Release the parts from the build plate and swish each in acetone for 5-10 seconds, then blow with compressed air.

The parts are squeaky clean after that.  I do all of this in a spare room that also contains my airbrush hood, so I run that as a vent during the process.  Acetone is not friendly to all flavours of resin, but it works great, and very quickly, for the basic resins.  YMMV.

[peteski]

Just keep in mind a few things...  First, DA is much more flammable than IPA.  If your basement workshop is in the same space as your furnace (as is mine), it's advisable that you clean your prints with DA somewhere else (especially if it's winter and the furnace cycles regularly).  Second, it's quite a bit more toxic than IPA.  Read up on it prior to using it and make the decision to switch (or not) once you've educated yourself on the health risks.

As I see it, maybe when compared to 91% IPA, since DA is 99% (close enough to 100%) strength, but I would think that a 99% IPA (which I use in my hobbies) is likely as flammable as (99%) DA.   Actually it is not the liquid alcohol that burns -- it is the vapors.  I would suspect that 91% IPA produces slightly less vapors than 99% DA.  Is there some specific source you can point me to which confirms this?  Not that I'm calling your statement invalid -- I would just like to learn a bit more about this.

[JeffB]

As I see it, maybe when compared to 91% IPA, since DA is 99% (close enough to 100%) strength, but I would think that a 99% IPA (which I use in my hobbies) is likely as flammable as (99%) DA.   Actually it is not the liquid alcohol that burns -- it is the vapors.  I would suspect that 91% IPA produces slightly less vapors than 99% DA.  Is there some specific source you can point me to which confirms this?  Not that I'm calling your statement invalid -- I would just like to learn a bit more about this.

That's a good question Pete and the answer is never make assumptions!  Looked up the MSDS sheets for both DA and 99% IPA.  Exposure, risk, toxicity and flash point are about the same between the two.  DA has a slightly lower (1°F) flash point than IPA.  Not much of a difference.

So guys...  A. Never assume.  B. Neither solvent seems to be more toxic than the other.

Jeff

[timwatson]

Thats what is interesting about resin printing, the way you respond to resin smells, ipa smells/vapors is just as varied as the person smelling!

I think IPA smells more strongly to me personally which is opposite some others here. So truly your mileage may vary quite a bit. I almost wonder if these kinds of smells are like tasting cilantro is based on genetics.

Anycibic resin smells awful to me which is why I stopped using it. Elegoo not so much. Personal preference is king in the end.

[Chris333]

And after 3-5 minutes humans start to tune out any smell.

[turbowhiz]

I confess that I'm not sure what the issue is with Joe's print.  Is the light powder on the flat spalling off the printed part?

In any event, my cleaning regimen involves no scrubbing, as my parts tend to be small and intricate:

* 1 swish in old IPA - I just take the entire build plate and swish it around, by hand, in the vat for ~20-30 seconds.
* Repeat in a 2nd vat of clean(er) IPA.
* Release the parts from the build plate and swish each in acetone for 5-10 seconds, then blow with compressed air.

The parts are squeaky clean after that.  I do all of this in a spare room that also contains my airbrush hood, so I run that as a vent during the process.  Acetone is not friendly to all flavours of resin, but it works great, and very quickly, for the basic resins.  YMMV.

I'm new to the resin game, but I've been using DA (or as we call it in the Great White North, "Methyl Hydrate") with good success, with some of Gary's designs no less. No scrubbing for sure...

A minute in the wash and cure 2.0 with the build plate (dirtier DA) and then another quick swish in another clean DA vat I have seems to get things nice and clean. I was originally washing it (a lot) longer, but it turns out to be strong enough to cause some untoward effects on the resin, which oddly enough appear to correct themselves with enough drying time... Maybe because recommended washing times are more centered on IPA, I don't know, but with the DA I don't find you need long to get it clean.

I'm using "Solveable" brand Methyl Hydrate, and the stuff stinks less then IPA, at least to me. And it stinks way way less then the Anycubic basic resin itself. Cheap, available and effective has been my experience.

[Chris333]

Is Coleman camp fuel good for any of this? Just because sometimes it is cheaper.

[peteski]

Is Coleman camp fuel good for any of this? Just because sometimes it is cheaper.

I believe that it is Naphtha, which is similar to Heptane -- used for dissolving wax in Shapeways FUD/FXD prints.  Naphtha is a non-polar solvent, where alcohol is polar (it mixes well with water where Naphtha is more like gasoline, it does not mix with water).  It would be interesting to see how Naphtha works in this application.

[peteski]

That's a good question Pete and the answer is never make assumptions!  Looked up the MSDS sheets for both DA and 99% IPA.  Exposure, risk, toxicity and flash point are about the same between the two.  DA has a slightly lower (1°F) flash point than IPA.  Not much of a difference.

So guys...  A. Never assume.  B. Neither solvent seems to be more toxic than the other.

Jeff

Thank you Jeff. Helpful info.

[turbowhiz]

Is Coleman camp fuel good for any of this? Just because sometimes it is cheaper.

At least around here, a gallon of Methyl Hydrate is only 75% the price of a gallon of Coleman fuel (Naphtha).

[JoeD]

More testing...defiantly not in the cleaning....the "debris" field around the part seems consistent in parts that are cylindrical laying on their sides.  Standing upright, not so much.  I set up a printing test with as many variable as I could figure and will run them this week once things calm down here.  It kinda looks, under magnification as if the layers may not be adhering to one another as it makes the transition up and over the outside radius.   I also downloaded the new print test sampler which is supposed to help identify the correct print time.  I'm also trying laying things at an angle which will take care of much of this...but with a part like these rocket canisters, printing flat makes an easier part to deal with.  I found a good scrub with a scotchbrite after its been UV cured helps clean up the area.

Thanks for all the input, hopefully this week I can come up with a resolution and if not, I'll fire off an email to Uncle Jessie on YouTube   LOL ..

JOe