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Made my first own vulcanized rubber, basically from latex milk, sulphur, zinc oxide and a few drops of Fairy dishwasher soap (non ionic tenside).

The soap helps with the mixing, the zinc accelerates the process. But it is the sulphur that does the magic: It builds bridges between the long polymer molecules.

Just 30 minutes in a normal cheapo kitchen oven (bought for 50 Euros on the web), and tt does work! Rubber as we know it. It stretches, it is dry, and it snaps back just fine.

The only issue I ran into: I stirred the ingredients to hard, which causes some foaming up (likely due to the soap drops). Next batch, more careful stirring - fewer bubbles.

The results are VERY ENCOURAGING - a stable product, it stretches to the familiar factor of 6:1 before it tears. Very snappy, too!



More experiments ahead.
 

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Very interesting, can you notice a difference to TBG?
 

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Discussion Starter #4
TBG is still the MUCH better product... so flawless and even. I will consider myself lucky if I can make rubber that allows me to make functional bands from the stuff. But that won't be easy. Lots of work ahead.
 

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Keep at it Joerg! You figure it out and we will all be ready after the Zombies land!;)
 

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Basic process is quite easy, but managing a good vulcanization is a very hard stuff.
Thera band won't become useless tomorrow and replaced by homemade rubber for our slingshots...

By the way, DIY vulcanization can be really cool to make some things such as a custom handle, etc

[edit] if you want to try further tests concerning vulcanization,
> you should get a PHmeter if you don't have one ( little bands on PH-paper do it quite well and are really cheap ), and try several tensides ( anionic/cationic, basic/acid )
> try to find a reliable recipe to make your tests and modify it. a good vulcanization can use up to 30 differents ingredients, such as peroxyde, calcium or carbon powder, oils, etc )

Good luck and have fun :)

[edit2] talking of custom handle, if there are some mad experimenters here, you can make your own plastic with
> milk : milk + vinegar to have caseine, pass the hot milk throw a towel, grab the caseine which remains in the towel then add some caustic soda. Put in mold. It is quite long to dry and harden, but the result is really good and long-lasting.
> potatoes or maize : starch potatoes or maize, glycerine ( you can buy it in your local pharmacy/drugstore ) and white vinegar. Mix white vinegar and glycerine in equal quantity, water ( 3 or 4 times the amount of vinegar ) and some starck. This is used for "bio-desintegrable plastic", plastic bags for example, which means it is not really durable.

I'm pretty sure you can find some videos on youtube or other which explains these experiments much clearier than I did :)

That's all for the off-topic, let's go back to rubber :D
 

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When I'm thinking you are reaching the limits..... You come with this.
I usually show your vídeos to friends and people on my jobs. They say - "this german guy is crazy"!. But everybody likes it. Specially your laughs. Demonstrates that you are really loving what you are doing. Thats the real point of everything!
You know, Jörg, you are my modern world hero (not Neymar, like everyone on my country-by the way, I hate soccer). No super powers. Just brains! And you found yourself the perfect vilains. Zombies, that want to eat your brains!

Keep on going!

Ps- I'm getting married next year. Not a fancy party, very small stuff. But I had this Crazy dream where you where throwing the wedding rings with a slingshot on the cerimony.....can you believe that?
 

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"The results are VERY ENCOURAGING… More experiments ahead."


Cool. Encouraging indeed! Looking forward to it. It would be beyond spectacular if you could come up with decent homemade rubber for functional bands.
 

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Discussion Starter #11
I found out that I need to let the rubber/sulphur/... mix sitting for about three hours. Then the bubbles have disappeared.

It will take a lot of experiments to get useable rubber for slingshots - but I am determined.
 

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I found out that I need to let the rubber/sulphur/... mix sitting for about three hours. Then the bubbles have disappeared. .
Joerg, have you thought about using a vacuum pump to lower the pressure. This will allow the bubble to dissipate more quickly. Even one of those food vacuum systems would work.

Brian
 

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I was reading about how all the plantations for rubber in Indonesia use offspring descended from 15 trees. Do you have several sources of raw milk?

Given all the known and unknown variables in natural materials, is some latex just better than others?

Could selective breeding for elastic properties be the future of slingshot rubber?

Excuse my inquisitiveness, but this is potentially the biggest mark a person could leave on the sport--at its basic level. Exciting stuff.
 

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Discussion Starter #14
Joerg, have you thought about using a vacuum pump to lower the pressure. This will allow the bubble to dissipate more quickly. Even one of those food vacuum systems would work.
Brian, that is an excellent idea! I will have to try it. I believe that a bubble free film is the key to useable rubber.

Slagskimmer Mike, I am sure that selective breeding can make a difference. Longer chain molecules = better performance. But I have no access to a rubber plant farm :(
 

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aiming the less
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Wasserstrahlpumpen gibt es ab 20 Euro, hatte ich vor 10 Jahren für Tintenpatronen-Refill gekauft. Weiß nicht mehr wo.

http://www.kurts-werkstatt.de/vakuumpumpen.htm

Wasserstrahlpumpen gehen vom Normaldruck 1000mbar bis ca. 20mbar Restddruck herunter. Käseglocken schaffen nur einige mbar herunter.

Warnung: 1kg/cm² Druck auf der Oberfläche des Vakuum-Behälters, kann zersplittern oder zerknüllen.
 
D

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Wasserstrahlpumpen gibt es ab 20 Euro, hatte ich vor 10 Jahren für Tintenpatronen-Refill gekauft. Weiß nicht mehr wo.

http://www.kurts-werkstatt.de/vakuumpumpen.htm

Wasserstrahlpumpen gehen vom Normaldruck 1000mbar bis ca. 20mbar Restddruck herunter. Käseglocken schaffen nur einige mbar herunter.

Warnung: 1kg/cm² Druck auf der Oberfläche des Vakuum-Behälters, kann zersplittern oder zerknüllen.

G_Y you should not seat on the vakuum box! :D


G_Y Du sollst Dich auch nicht auf den Vakuumbehälter setzen! :D

Joe
 

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Discussion Starter #18
Es geht mir ja nicht um ein Wahnsinnsvakuum. Ich möchte nur die Standzeit für die Milch reduzieren. Dazu genügt eine gewisse Reduzierung des Luftdrucks hoffentlich.

Eine Pumpe allein hilft mir nicht, ich brauche auch eine geeignete Unterdruckkammer - möglichst transparent, fürs Video.
 

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Hey Jörg!
Ne weile nüscht passiert hier...
An den 1000 Filmteams, Reisen und Terminen kanns ja wohl nicht liegen, oder? :p;)
Als Vakuumpumpe benutze einen: STAUBSAUGER!!! Als Vakuumbehälter geht eine mit einem Gummiring aufgelegte Glasschüssel oder ein Glaskochtopf.
Das eine hast du sicher, das andere kostet nicht sooo viel.
http://www.ebay.de/itm/Glaskochgesc...s_Garten_Kochen_Geniessen&hash=item41760bc072
Auch wenn du wohl ne andere Grösse brauchst.
Das Loch für den Staubsauger kommt in die Platte auf der die Schüssel liegt.
Grüssle, Kai
 
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