How To Make Your Own Sugru Substitute

 by mikey77
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Step 3: Mixing Oogoo

mixing1.jpg
tapeit.jpg
Mix By Volume
As stated before, Oogoo is simply a mixture of clear silicone caulk and corn starch. It can be mixed anywhere from 5 to 1 to 1 to 2 silicone to corn starch by volume. Up to a point, the more corn starch you add the faster it will set up. I like to mix it in small disposable cups using a Popsicle stick that is wrapped with Gorilla Tape to create a spatula. See pic4. Once it cures the Oogoo peels easily off the tape wrapped stick and the mixing/spreading stick can be reused.

Mix In Small Amounts
A good starting mixture to try out is 1 corn starch to 1 silicone by volume. It is easiest to mix it in small quantities so as to have plenty of time to work it. To see how it works, you could start with 1 tablespoon silicone caulk to 1 tablespoon of corn starch. You can reduce the amount to as little as 1/4 tablespoon corn starch to 1 tablespoon silicone if you want more time to cast it or sculpt it. I rarely mix up more than 3 tablespoons of silicone at a time.

The dry starch and sticky silicone do not want to easily mix. But if you are persistent and keep quickly stirring and mashing the mix, they will eventually merge into a thick paste. The resulting Oogoo is very sticky and will stick to anything that you spread it on. Most things it will stay well glued to. On a few things like some plastics and metals, it will easily peel off after it has cured.

The resulting Oogoo is a nice reflective white but I recommend coloring it so that you can easily see if you have an even mix. See the coloring step.

WARNING: While mixing, Oogoo will give off the strong smell of Acetic acid which can be irritating to the eyes and respiratory system. I strongly recommend that the mixing and forming be done outside or in a VERY WELL VENTILATED room. You should also wear nitrile gloves while mixing as the uncured silicone contains other solvents that might be absorbed by the skin.

One recurrent problem with silicone caulk is that once opened, it will tend to set up in the tube tip. To get a good seal I have had good luck using Gorilla tape wrapped over the tip. See pic4b. If you leave a quarter inch gap between the wrapped tape and the tip you can squeeze out just enough silicone to seal the tip well from air and moisture.


 
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willrandship says: Sep 30, 2012. 1:49 PM
So, does it have to be 100% silicone caulk? Also, does it have to be clear, or is that just your preference so you can dye it?
mikey77 (author) in reply to willrandshipSep 30, 2012. 9:36 PM
100% silicone works the best. Colored silicone can be used but the coloring additives make it less flexible and and less adhesive.
escapefromyonkers in reply to mikey77Mar 20, 2013. 5:33 PM
luckily i found this , without having to read through the 400 plus comments. i thought i bought clear,but bought white, i now have bought clear, however i realize tat the white is at its expiration date. It seems the silicone caulk has about a 1 year expiration date from time bought. Something to keep an eye out for. i bought it the first time about a year ago, but got sidetracked.
I also noticed that the brand of silicone caulk i bought has two types that are clear and give off the vinegar smell, they stick to different surfaces better, one for bathrooms, one for windows household, i will use them all and see what happens. My original question was concerning the colored caulk, and i caught the answer, It should still work for some uses, i noticed the artist paints in tubes are linseed oil based, and i have linseed oil to thin. hopefully we can get a cliff notes of what all the different mixtures , such as talc and chalk and bicarbonate soda have worked for something or not. I know the original baby powder from talc also had additives, when i was a scuba diver, we didn't use the baby powder on our dry-suit seals, only talc from the pharmacy, the perfumes and additives could cause the seals( latex) to breakdown.
Great information and thanks to all for sharing their trials and errors. I agree with the early response od do it and see what happens, as long as it is not a possible dangerous reaction. The added bonus of thinning the silicone for mold making and quick drying, i will also try. Thanks for the info.
pirobot668 says: Oct 27, 2012. 4:01 PM
Has anyone used Cabosil? Ultrafine silica powder, a gallon of the stuff weighs about 2-3 ounces. Enormous surface area/volume ratio, slightly hydroscopic. Should have enough moisture....
Since it is totally inorganic, and based on silicon, should be compatible and not rot.
dbliss3593 in reply to pirobot668Nov 19, 2012. 9:38 AM
Isn't silica carcinogenic?
shannonlove in reply to dbliss3593Jan 25, 2013. 11:22 AM
You realize that "silica" is just sand, right?
mattopensource in reply to dbliss3593Dec 7, 2012. 8:19 AM
When in really fine powder form (cabosil) and inhaled it can cause silicosis.
veeguy in reply to mattopensourceApr 7, 2013. 11:15 AM
I live in a city that has a large factory making sinks and bathtubs. The company has a large health clinic that I worked in during summers when I attended college.

One of the main duties was to assist clients in using the respiratory therapy machines, of which there was a large room full. Each client would come in twice a week for an hour of "treatment" which consisted of breathing a solution to "cleanse" their lungs. I asked one of the regular clinic workers why there were so many machines and so many patients and she told me the story .

There were finishing lines where workmen would grind out and repair flaws in the ceramic coatings. Ceramic is silicon. This was before the health problems caused by breathing fine silicon dust was realized.

She then told me that in years past there were 3 large rooms filled with the machines, but as the clients died off from silicosis, they no longer needed so many machines. Silicosis is a particularly gruesome way to die, as your lung capacity is gradually reduced to nearly total suffocation. I myself have reduced lung capacity, and I can tell you that of all the things that are over rated, Breathing is not one of them.

If you do try the Cabosil, take *every* precaution against breathing any of it in. Wear an air supplied respirator if possible or at least a properly fitted N-95 rated "nuisance dust mask". (do a bit of research before using it to ensure the particle size is not too small for a N-95 mask to filter out first!)
superpants says: Feb 24, 2011. 12:41 AM
I have been experimenting with something similar myself- mainly as I wanted to custom colour silicone. I have found that talcuum powder works well as a substitute for the cornstarch- I tend to mix a small amount of water with it and the colouring to form a paste, and then mix with the paste with the silicone. The key advantage of the talc is that it is in-organic so there will be no issue in the future with it supporting fungal or bacterial growth. Hope this helps some people!
giulio.m in reply to superpantsNov 10, 2012. 7:14 AM
Hi All! I've been reading most comments with great interest. Did anyone ever try to use calcium oxide or even calcium hydroxide instead of cornstarch? Thanks a lot and keep with the good work!!
gweeter in reply to superpantsMay 17, 2011. 3:27 PM
Are you using actual talc powder or baby powder (which I believe is is actually cornstarch based)? What once was used as baby powder no longer contains actual mineral talc because talc turned out not to be that great to be exposed to in large quantities.
shannonlove in reply to gweeterJan 25, 2013. 11:34 AM
Natural talc is a mineral that also sometimes contains thin fiber structures that are classified as asbestos. When the great asbestos panic/lawyer-gold-rush started three decades ago, people got convinced that asbestos would kill you if you just looked at it so anything with asbestos.

Like all minerals, the carcinogenic properties of talc, asbestos, silica (sand) etc all come from mechanical abrasion causing irritation, inflammation, cell production etc which can eventually cause a cancer. However, to get any significant chance of actually getting cancer, you have to exposed to literally 10,000 times or more than you would in normal use.

Prior to the 1970s, asbetos was the ONLY flexible fire proof material and they put it in everything from gas hoses to all types of tiles, insulation etc. Basically, everything that might at some time face heat or fire had asbestos put in it.

Yet, the number of cancers caused by asbestos remain microscopic for the generation exposed.

In the case of talc, you could use natural talc once a day, everyday for decades and it would have the same statistical effect on life expectancy as crossing the street once or eating five bananas (from radiation from the potassium.)
crazycloud in reply to gweeterNov 15, 2011. 10:43 PM
Have not verified but, I heard that it may cause vaginal and or cervical and or uterine cancer. I wouldn't let it touch my skin.
pirobot668 in reply to crazycloudOct 27, 2012. 3:57 PM
Some grades of Talcum powders once contained -traces- of asbestos. Topical application has not been proven to cause prblems, but the airborne dust.....
With a better understanding of the risks, manufacturers are using higher grades of Talc which eliminates the asbestos problem.
There are 'industrial' grades that may have asbestos, but this is supposed to be clearly labelled as such.
Cosmetic/personal use grades have a GRAS status.
superpants in reply to gweeterMay 18, 2011. 1:02 AM
Interesting comment- In short, I don't know, I had made the assumption that talcuum powder still was talc. I'll have to investigate.
superpants in reply to superpantsMay 18, 2011. 1:52 PM
It is genuine talc- not cornstarch, so no issue!
DrPeper in reply to superpantsMay 10, 2011. 10:38 AM
AHHH!! I see someone else had the Talc idea! Good to see!
Segment in reply to superpantsMar 19, 2011. 2:27 AM
I've tried talcum powder too, for the reason I didn't want organic stuff in it. I don't know if it rots eventually, or gets eaten by bugs...

I thought it was ok, but then I tried gypsum powder (to make molds with). That worked much better. (no water, 1 part G 1 part S)

But I would like to know if there will be a (chemical) reaction between the silicone and the gypsum in the long term... Maybe someone can tell me, so that I don't have to wait for a year to see what happens :-)
tktaylor in reply to SegmentFeb 6, 2012. 11:33 PM
Quick question though, where did you get gypsum powder?
sirtom68 in reply to tktaylorApr 25, 2013. 3:32 PM
Drywall patching in powder form is Gypsum.
Segment in reply to tktaylorFeb 7, 2012. 2:25 AM
Maybe it is also called plaster of paris? I got mine in a ceramics supply store. I live in Holland. I suppose you can get it in diy stores too, but I think there will be some kind of glue mixed into it.
tinker234 says: May 21, 2011. 4:59 PM
hi inthebathroom recomend me here i just want to know the consictcy for s human like skin
mikey77 (author) in reply to tinker234May 22, 2011. 7:54 PM
A mix of 2 corn starch to 1 silicone caulk gives a smooth texture to the Oogoo that feels very close to human skin.

I have been trying to come up with an Oogoo foam that will also give it the resiliency of skin, but so far no luck.
roliop in reply to mikey77Mar 9, 2012. 3:23 PM
I had a quick go at making some foam which came out slightly better than just adding bicarbonate.

My hunch was that adding gelatine might help. And more vinegar, since the amount in the caulk isn't enough for many bubbles.

So my next batch is a Gummibear disolved in strong white vinegar and mixed with cornstarch. Hopefully I can mix the bicarbonate into the caulk and then get the starch gloop in fast enough for a half-way homogeneous mixture before it all takes off. :-)

Maybe you've done some more experimenting in the meantime.

rp
roliop in reply to roliopApr 30, 2012. 2:35 PM
Foam update.
I think I got the best foam by dissolving the bicarbonate first.

I suspect that mixing it into the caulk in powder form is the cause of it becoming brittle later.

rp


neodymium in reply to roliopOct 13, 2012. 11:18 AM
This may be a bit late but what did you disolve the bicarbonate into? and what ratios did you use for the bicarbonate, gelatine, white vinegar, and oogoo?
sdunn2 in reply to mikey77Jun 5, 2011. 7:39 PM
I've tried the following combinations tonight:

* I mixed Elmer's Carpenter's Wood Filler with GE Type 1 silicone (the same type here), 1:1 ratio, and I have cellulite/flesh-like flexible and foamy consistency. It's still very flexible after a couple hours, so I assume it will stay this way. It set up slightly slower than the corn starch, but still quickly.

* 1:1 ratio of corn starch and silicone, and it worked as advertised (woohoo!), setting up quickly.

* 1:1 ratio of baking soda and silicone. I expected some kind of 3rd grade science project reaction, but I got nothing. It's crumbly and useless.

* 1:1 ratio of Johnson&Johnson baby talc powder and silcone, and there was no setup at all. It's basically drying like normal caulk. Fail.
eamc317 in reply to sdunn2Jun 17, 2011. 5:57 PM
Thanks for sharing your results! Will defidently help in the future.
tinker234 in reply to mikey77May 23, 2011. 6:15 AM
thanks look at scifi materials on here there is rubber that felt like skin it is creepy but cool
dinhoconrad says: Sep 28, 2012. 12:59 PM
Can I use this to make a custom earbud? Or is not ok to let this in contact with my skin?
pixelbandito says: Sep 8, 2012. 6:37 AM
For sealing caulk tubes, I find sticking a large nail in the end of the tube works really well. Cheap, and reuseable, as long as you haven't cut the opening too large.
tws1818 in reply to pixelbanditoSep 13, 2012. 9:07 PM
Hello,
For those that would like a pourable version ...use 1-1-1 parts of
100% silicon caulk (white or clear)
Corn starch
Naptha or paint thinner....Naptha will set faster but costs is a little more.

I use this ratio to create molds to pour my fishing lures...like soft rubber worms..etc....it will stand heat up to 500 degrees.

Mix very well....NO LUMPS.....this ratio will start to set in 40 min...and be fully cured in 4-5 hrs....I let mine set for 24 hrs before i put them in full use.
siamonsez says: Apr 1, 2012. 4:07 PM
I was thinking about using this as a substitute got gel coat in my hot tub since I patched some problem areas recently and wasn't able to get the marine-tex stuff I used to go on smoothly in some of the funny shaped areas.
Does anyone have any idea about what would happen to it when underwater and exposed to the chlorine/bromine that will be in the watter?
Also, any suggestions on a mix that dries a bit harder and is easy to work with? I.e. spreading and shaping it?
lrdforster says: Mar 14, 2012. 9:04 AM
I was wondering if food dye wood work as a colourant. im not sure it would mix with the silicone before adding the corn starch but I am sure you can dye the corn starch before mixing but not sure the starch will dry the silicone as quick.

Any Comments? Has any one tried?
rionmv in reply to lrdforsterMar 15, 2012. 10:33 AM
I mixed up a batch of this for my kids (and me) to play around with. I used food coloring to color it and it turned out fine. I mixed small amounts of oogoo and added a few drops of food coloring during the mixing process. There might be some advantages to using some of the other dyes or paints - darker colors being one - but everything turned out great with the food coloring. I can post pic if you'd like to see.
lrdforster in reply to rionmvMar 15, 2012. 12:05 PM
yes I decided to try myself last night I had the same result
janetsellers08 says: Feb 6, 2011. 12:29 PM
Okay, so I made a little sculpture with this BUT: I got it all over my hands and my comment is to help people remove this great goo from their skin. I used an orange oil cleaner as well as Dawn dish soap (original only - the one they use to clean up wildlife from the oil spills). It worked well, but I had to wipe off my gooey hands several times with paper towels (not so hot) and sacrifice a couple of microfiber towels.

I was, stupidly, thinking that the oogoo would just mold like a clay without fully mixing in the cornstarch.
the_sphynx_82 in reply to janetsellers08Oct 21, 2011. 10:39 PM
The first time I made Oogoo I almost had a heart attack because I got it all over my hands and kitchen counter and couldn't get it off right away. Since then I've learned that
1) If you wait the 5 or so minutes it takes for the stuff to harden, you can peel it off of just about anything with a smooth-ish surface that it can't ooze into (cloth is the biggest thing to avoid in my experience)
2) If you mix the Oogoo thoroughly enough that it starts crumbling away from itself (usually at about 60 seconds of mixing for a small batch) you can begin to handle it more like a putty than a glob of goop, especially with a bit of extra corn starch on your hands to keep it from sticking.

Hope this helps! :)
crazycloud in reply to the_sphynx_82Nov 15, 2011. 10:32 PM
This would probably be a good way to remove cactus needles. I have a cactus garden and usually use white glue, but it doesn't get the ones that are really in there. I will have to try this next time. LOL
killbox in reply to janetsellers08Oct 6, 2011. 10:02 AM
you can handle it directly either by cornstarching your hands. or by dipping your hand's in some water. Water will accelerate its hardening, but i find the technique valuable for sculpting/smoothing/packing molds,

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