Introduction: Gunge
Step 1- Gather materials
The main ingredient in gunge is a food thickner. There are a number of options open to you.
If you are in the UK Natrosol HR250 (often mis-spelt Natrasol) from The Basic Chemical Company (see address below) is a good material. This is the supplier the BBC have used (not sure if they still do, but I wouldn't be surprised)- You will need to buy a minimum of 1 kg of the natrosol, but this makes a good gunge.
The Basic Chemical Company (UK) Ltd
Hillbottom Road
Sands Industrial Estate
High Wycombe
Buckinghamshire
HP12 4HJ
01494 450701
http://www.basicchemicals.co.uk/
Ebay/ other websites
There are other suppliers that well sell you smaller quantities, either found on the web or through Ebay. Personally I don't believe these generally offer particularly good value, unless you only want to make one bucket full. It is likely (although I stand to be corrected) that these suppliers are selling on re-packaged Natrosol .
Xanthan Gum- this is sometimes available from the supermarkets (certainly Sainsburys) or health food shops as it is used as a gluten replacement.
Guar gum- another alternative that can sometimes be found in health food shops.
If you are in the US, you can use Methylcellulose (Methocel) from The Chemistry store- www.thechemistrystore.com or Ethylcellulose from Douglas and Sturgess- www.artstuf.com
Elsewhere you may need to find a local source for one of the thickeners.
The substances used to make gunge generally have long shelf lives (normally several years) and so can be bought in larger quantities and stored if desired. Moisture is their biggest enemy, so they will need to be packaged in a well sealed container.
Possible thickeners
You will also need
powder or poster paint
Suitable container to mix in- bucket for the quantity described
Scales
Wooden spoon, whisk, paint stirrer or similar
Step 1: Safety
Whilst I have been careful to only recommend materials that are not known to have any significant health risks associated with them, they cannot be classed as completely hazard free.
The largest single issue is the slipperiness of the gunge- it can be very easy to slip over on. It is therefore essential to consider this when planning any activities involving gunge, including clean up and washing off as the most significant effects will be found on a smooth surface such as a bath!
Most of the materials are supplied as relatively fine powders, and as such create nuisance dust. It is therefore worth wearing a dust mask when handling large quantities. Likewise if this dust gets into eyes it can cause irritation so goggles may be appropriate.
Most of the materials are sold as safe for skin contact and to date I have not had any problems with this. I would however be slightly wary of allowing prolonged skin contact with the colourants as it may stain!
All of these main materials are not hazardous when eaten, however many are used as laxative additives, so it would probably be unwise to consume large quantities !
In addition to the specific information above, general safe chemical handling practice will further reduce the risk of any issues, in particular;
Store materials in sealed, well marked, containers in an area out of reach of children and pets
Wash hands before and after handling these materials
Dispose of excess/ used materials/ empty packaging responsibly
Wear dust mask when handling powders
Clean up any spills quickly- Avoid using water to stop the area becoming slippery
Do not use utensils/ containers/ cleaning cloths that will be later used for food
Supervise children if they are making the gunge
Step 2: Step 2- Prepare the Ingredients
Measure out the following quantities of materials. I use plastic cups or a jug to do this, but a piece of folded paper will work as well. Quantities do not have to be precise, but it may help you make a batch the same in the future if you can be fairly accurate.
The water can go into the mixing container straight away.
Powder paint 160 grams (2%)
Thickener 96 grams (1.2%)
HOT water 8 litres
There will be variation in the properties of the gunge, most importantly the viscosity (thickness), dependent on the materials used. It is therefore worth experimenting with small quantities first before you make a large batch, until you have a goo you are happy with. The quantities given in these instructions will work well with natrosol, and will therefore serve as a good starting point.
You will want to mix up in an area where a spilt mess can be easily cleaned up, so probably not your living room!
Step 3: Step 3- Mix
Start by mixing in the colouring into the water- 2% will give a good level of colour and opacity for most uses, but dependent on what you want to use your gunge for you may need to vary between approx 1% and 5%. Liquid poster paint (tempera) can also be used, but I wouldn't recommend food colouring as it stains easily.
Water must be hot for the mixing to work correctly. If natrosol is dispersed into cold water, the thickener tends to drop out and form a jelly that won't then mix correctly. I tend to use hot water straight out of the hot tap.
Add the powder into the water slowly whilst stirring thoroughly and keep stirring until you notice the water starting to thicken up. This will usually take a couple of minutes. Sieving in the
Leave the gunge to stand before using it. It will need time to cool, and as the viscosity slows convection, this will take a lot longer than ordinary water. For natrosol the mix will take about an hour to thicken up to full viscosity- I often leave it to stand all night. Other thickeners may need a different length of time
Step 4: Step 4- Using Your Gunge
Use it on a slip and slide, fill water pistols with it,enjoy tipping it over your friends, fill a bath with it, re-create your favourite messy game show, use it in your next blockbuster alien home movie, pretend to be a Ghostbuster, fill a cauldron with it for an unusual lucky dip, challenge your friends to a messy wrestling event or find other uses for it the world is not a gooey enough place....
It is possible for the gunge to stain, so keep away from soft furnishings and make sure any clothes that get covered are washed thoroughly and preferably before the gunge dries.
The gunge can be disposed of down a normal drain, but it is well worth diluting it with water first so that it flows easily and doesn't block your drains. If left to stand for a few days after use it well genrally break down to a watery consitency, which will aid disposal.
If you want to know more about making gunge, or messy games, visit my website: http://www.superpants.net

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13 Comments
6 years ago
For anyone looking at this now, even though this is kind of an old 'ible, I've found that sidewalk chalk an be powdered up and used as powdered paint if powdered paint is inaccessible. It might even be less staining?
6 years ago
Has anyone figured out how to prevent colourant from staining skin ?
8 years ago on Introduction
Couldn't dyed instant vanilla pudding work for a sort of gunge/slime too? And there'd be no real health concerns as it would be completely edible due to being pudding and food dye and all.
9 years ago on Introduction
BLUE!!!!!
9 years ago on Step 4
Gunge fight! X3
11 years ago on Introduction
baught som Natrosol 250 H4R
cant get to gel at all. is H4R the wrong stuff? on container says typical usage 0.1 to 3%.
have mixed with hot and cold water... could there be a ph issue?
Any ideas welcome
Reply 11 years ago on Introduction
There are a few things to try that might solve the problem. The first thing to check would be that you have been sold what you think you have bought, and also if the batch is still in date.
The most common problem I have found with Natrasol is the tendency for it to ‘drop out’ and sit on the bottom of the container and form a jelly lump. This will happen if the water is not hot enough, but won’t be apparent when you initially mix it. Once this has happened, it is very difficult to recover from. When you mix- it will look like it is dispersing, but will slowly settle out as it sits. No amount of mixing after this has happened will get it to thicken properly.
The H4R grade shouldn’t have any significant effect as far as I can tell.
Hope this helps
11 years ago on Introduction
If you want to whip up a batch of "boomer bile" (from the Left4Dead game), McCormick has a neon green food color that works perfectly. We made our bile using Xanthan Gum powder 1% in water, which yields a nice, translucent, snotty looking glop (we ordinarily use Xanthan 1% as a oral suspension base in prescription compounding). If you use xanthan, allow it to hydrate overnight, then mix in a blender or with an electric mixer.
11 years ago on Introduction
Yes zjschafer corstarch and water works very well
11 years ago on Introduction
would cool aid work to give it color?
Reply 11 years ago on Introduction
It probably will work, but you won't have a particularly intense or opaque colour
11 years ago on Introduction
If available, the powder paint tends to stain less. With the poster paint it can depend on the brand and the colour. I would therefore recommend washing any clothes before the gunge dries and only using older clothes and darker colours.
There is a full explanation on this on my website http://www.superpants.net/gunge.html
11 years ago on Introduction
Be a little careful with the type of poster paint you use. Despite being water-based, some of them are surprisingly hard to wash away if you happen to let them dry. Though I'll categorically deny any personal experience!