Isopropyl alcohol 70%

Post #1 » Wed Oct 30, 2013 12:41 am

Hi, I saw that one is advised to use Isopropyl alcohol 70% to clean the prints.
I just tried to source a local supplier and they have 100% alcohol, is this ok for cleaning the prints?
And if not, is Isopropyl alcohol 70% just mixed with water? Does anyone know if I can just add to it 30% water?

Thanks

Post #2 » Wed Oct 30, 2013 2:44 am

70% is not ideal, 90% is better, as the water some times leaves "white crusties" behind (it seems).

Post #3 » Wed Oct 30, 2013 3:27 am

ok. And how about 100% alcohol - using this would be fine? if not is 90% just a mix with water?
I'm just preparing all the things I need before the printer arrives :)

Post #4 » Wed Oct 30, 2013 5:40 am

I've not tried 100%, it should be fine, but perhaps requires more handling precautions?

Post #5 » Wed Oct 30, 2013 7:36 am

I use 100% with no problems. I'm fairly sure you could just add distilled water to it to make 90%, but just use it full strength :)

Post #6 » Wed Oct 30, 2013 11:10 am

Whats the difference between Isopropyl alcohol, and just plain alcohol? does it matter for cleaing the resin off the prints? or cleaning the PDMS?

Post #7 » Wed Oct 30, 2013 1:22 pm

Isopropyl alcohol is the only type we suggest for cleaning.

Post #8 » Wed Oct 30, 2013 1:53 pm

I normally use Acetone to clean the print out and Soap solution to clean the pdms sheet. Aetone cleans the print out perfect. Does it cause ant damage to the print out I do not Know.

I noticed that Acetone smokes the Silicon sheets,
I have also noticed PDMS lasts longer when used with soap that with alcohol

Benoy

Post #9 » Sat Nov 02, 2013 11:18 am

curios why if it is used for cleaning why not use denatured alcohol? I have a lot of that on hand that I use at the bench to prevent heat scale.

Post #10 » Sat Nov 02, 2013 12:05 pm

Tim, Robert Howle here, I use a pyrex baking dish with a snap on lid and have been cleaning my build table and sweeper in it for over 3 months. U don't use as much isopropyl. Only use fresh alcohol to clean models from the squirt bottle. I always wash my models with soap and water after and dunk in the ultrasonic, final rinse with distilled water.

Post #11 » Sat Nov 02, 2013 2:06 pm

I keep reading how rinsing with water before curing in the UV lamp results in white residue and artifacts... Yesterday, I got myself a new UV lamp and rinsed a new printed part in tap water, then with alcohol before throwing it into the UV lamp right away.. When I got back after an hour, there were white residue all over the print. I thought it must've been water I washed with.

well.. today I printed a part again and decided to wash the part with alcohol only.. I started seeing bits of milky white droplets form all over the part before it dried and before I threw it into the UV lamp, so now I'm left wondering if its the water or the alcohol that causes it, or perhaps its just resin reacting with either the water or alcohol you use. I guess whatever you wash your part with, its best to make sure you give it a final was with clean water or alcohol.. Do not recycle the liquid.. and also let it air dry first before throwing it into a UV lamp.

Post #12 » Sat Nov 02, 2013 2:29 pm

It is the alcohol and water combo in my opinion . Use soap and water, then final rinse with distilled water and u won't see white crusties. U need the alcohol to remove the uncured resin. Isopropyl is oily, and leaves a residue on the model and this reacts somehow with the water. I believe this is the cause of white crusties. I haven't had any since I went to the soap and water and distilled water finish.

I did an test by rinsing a newly printed model in alcohol (drained it into a dish). Then rinsed with water (let that go into the same dish). The result was a white precipitate that formed in the dish. A result of the iso and water with uncured resin mixture. My conclusion is that any alcohol residue must be removed before final rinse. The soap and water gets rid of the alcohols oily component.

Some are using the ultrasonic after the alcohol wash. I have been doing that myself with no ill effects. Still do final rinse with distilled water.

Post #13 » Sun Nov 03, 2013 9:56 pm

I'm using 99,92% (I'm pretty sure that you can't really find ideal 100% isopropyl) and it is pretty fine. Moreover I'm using it in the Ultrasound (ultrasonic) cleaner. And last month or two proved it without any accidents. Yes, yes, yes I know that it is flammable, dangerous and so on. But hey, breathing all of that isopropyl vapours is not dangerous?

Post #14 » Sun Nov 24, 2013 1:22 pm

I personally found the trick with 70% (all i have used...) is spray the part off, rinse as much as you think necessary with the alcohol. Let part sit for a while to dry. THEN cure it, and you shouldn't see any white crap. I don't even rinse mine in soap. Not sure if that is important or not. They just smell like the resin when dry & cured.

Post #15 » Sun Nov 24, 2013 2:58 pm

whatever you wash it with (alcohol, water, water/alcohol mix etc), as long as you let it air dry before throwing it in the UV lamp, it should cure without any white residues :)

Post #16 » Sun Nov 24, 2013 4:38 pm

As others have suggested I have started putting models in the ultrasonic after alcohol and soap and water. You should see all the white cloud of gunk that comes off the model (from all the small crevices). Super clean, then rinse distilled water, dry, put under cure lights. Have not had a model damaged using this method so far.

Robert