Tutorial | How to make and use Sprue Goo |

Exclusive Preview for Newsletter Subscribers 19 October 2021
BJ talks about Sprue Goo. What is Sprue Goo?
Sprue Goo is polystyrene plastic that is chemically melted into liquid plastic by adding plastic cement. The liquid is then used to fill gaps, add strength or creating texture on surfaces.
Use your leftover sprue from your kits and create this very useful and versatile Sprue Goo.
As a filler, Sprue Goo has the advantage of bonding to both sides of the plastic part whereas regular fillers can pull away from the plastic being filled.
Add strength by adding fillets of Sprue Goo to add mechanical strength to parts.
Create rough textures by brushing Sprue Goo over the surface of your model.
Sprue Goo will bond to any surface and material.
On smooth materials such as glass, the dried Sprue Goo can be peeled off and used as a thin sheet for scratchbuilding.
Items used in this tutorial:
Liquid Cement
www.hearnshobb...
Polystyrene plastic
Use the leftover sprue/runner from your plastic model kits
****************************************************************************
Sign up and let us know what you would like to see in the next videos.
Newsletter: www.hearnshobb...
Instagram: bit.ly/35wCikH
Facebook: / hearnshobbies
Facebook The Hobbyman: / hobbymannarrewarren
Twitter @hearnshobbies
Twitch: twitch.tv/hearnshobbies

[@tippo5341]

Great content and much more thorough explanation of the goo’s use than many other tutorials, thanks guys 👍🏽

[@HearnsHobbiesMelbourne]

Glad you found it useful. Thank you for watching!

[@johnnoble01]

Don't understand why people wet their pants over sprue goo . There are better alternatives out ready to go without messing about with bits of plastic and cement. If you want a sg replacement try thinning normal filler with tube cement. You can get the consistency you need without having to mess about.

[@wRAAh]

0:51 If the bottle is low, you can lower the brush by pulling it out a bit with a pair of pliers. It's designed with that in mind!

[@HearnsHobbiesMelbourne]

Great spot! I have a video showing how to do that: kzbin.info/www/bejne/Z2SuoK2Ygt1qZqc

[@rosemaryr.long-morgan9704]

@@HearnsHobbiesMelbourne Thanks for getting back to me. Ok thanks, I will

[@marknorris5269]

u are using a plastic tub for this project. Does that not melt when you add the glue to the sprues?

[@HearnsHobbiesMelbourne]

The tub is polypropylene so not affected. However, the tub is used just for this demonstration to be easily viewed. As it does not seal well, the cement glass bottles work are recommended.

[@BennyCFD]

Or........you can use a bottle of Tamiya thick cement. Just leave the cap loose for a day or so and the solvent in it will evaporate a little or until you get the thickness you want.

[@HearnsHobbiesMelbourne]

I don't think evaporated cement can ever get as thick as making sprue goo.

[@kenjones3715]

Hey BJ what other solvents could be used ?

[@HearnsHobbiesMelbourne]

Hello Ken. Any brand of thin styrene cement can be used.

[@paulgertsch7105]

You never discussed the Mr Hobby cement that you had on the table. But I guess that you can also use it to make the spru goo ?

[@HearnsHobbiesMelbourne]

Yes, that is correct. Any thin welding cement is suitable to make sprue goo.

[@sabrekai8706]

I've made up 3 different batches. Tamiya extra thin, and sprue from the model I am working one. Thin or thick makes no difference. Fill the seam, let it cure for 24hrs and shave it down. I get hundred of tiny bubbles, .1 mm and smaller. So far apparently I'm the only person to have this happen. Any idea why?

[@HearnsHobbiesMelbourne]

Small bubbles are created by the solvent evaporating. You see these if the solvent does not mix well with the plastic you have selected. Try a different brand of plastic.

[@sabrekai8706]

@@HearnsHobbiesMelbourne Thank you. I'll try using store bought plastic, the sprues I used came from various different manufacturers.

[@geod1972]

Has been happening to me for ages too so you aren't the only one. Thanks to Hearns hobbies for the info re trying different styrene

[@raymondchapman5990]

What nippers are you using ? They orange handle pair ?

[@HearnsHobbiesMelbourne]

Thank you for watching. The nippers are the Ninesteps Premium single bladed. You can get them here: www.hearnshobbies.com/products/nine-steps-premium-side-cutter-nipper-super-slim-jaw

[@schirmoau]

Thanks Guys very handy hint for someone who's only just back in the game after being absent for 30 years!

[@HearnsHobbiesMelbourne]

Glad you found the tutorial useful!

[@leonardusgroenendyk6027]

The Tamiya brush is extendable so when you are running low it will reach the bottom....check it out.

[@HearnsHobbiesMelbourne]

Thanks for the tip Leonardus. It is extendable by about 1mm before it feels loose.

[@anshuldwivedi1919]

How many models does a typical 40ml bottle of the cement last?

[@HearnsHobbiesMelbourne]

This is too difficult to say as there are so many variables. Please purchase one and try it.

[@howardmoon2687]

I made a bottle of thin mix for thickening joints. Among other uses, but mostly for joints.

[@HearnsHobbiesMelbourne]

That is a great tip! You mean joints in Gundam and the like right?

[@howardmoon2687]

@HearnsHobbiesMelbourne Correct. Since it bonds to the plastic, it's very durable. And it is easy to control. Just apply thin coats until you have the desired thickness on the joint in question. If you go too far, a light sanding sorts that out. It just takes longer than the usual methods because you have to wait until the plastic is completely cured to avoid accidentally gluing a joint. But the end results are worth the wait, in my opinion.

[@sg8412]

Great video. What is the shelf life once you've made the sprue goo? Will it harden inside the bottle over time? Will the brush clog up? Thanks in advance, Cheers, Steve

[@HearnsHobbiesMelbourne]

Thank you for watching! The shelf life depends on how well your bottle seals up. When you notice the sprue goo becoming thicker, just add more cement to dilute it. With this maintenance, and refeeding with plastic pellets from time to time, your sprue goo will live forever! Your brush will stay free as long as it is submerged in the sprue goo. If the brush needs a clean, just let it soak in some plastic cement until it frees up.

[@sg8412]

​@@HearnsHobbiesMelbourne Brilliant! Thanks for the info. Most helpful.

[@montlejohnbojangles8937]

Cool! Thanks man, that's a neat trick. Never really considered this, but it'll make a good use for my old bottle of plastic glue! ✌️

[@HearnsHobbiesMelbourne]

Happy you liked it! Once you make a bottle and have it handy, you will be amazed at how handy it becomes.

[@Mackenzi]

Is there any danger of the liquid cement melting the plastic container that you’re putting it in? I have two brand new bottles and I would like to make this stuff but I don’t want to dump out half of one of them to do it, so I’m trying to find a container that’s safe to put the extra in.

[@HearnsHobbiesMelbourne]

Glass containers for solvents work the best. There are some plastics that will be ok with solvent cement but you will need to test before using.

[@Kaijushorts]

Great stuff guys, I've been trying to look into this for a while, I've got some old kits that really need a good solution like this

[@HearnsHobbiesMelbourne]

Thank you! This stuff is very handy. You can also make a few bottles with different consistencies. Clear sprue goo is good to make and use too.

[@rosemaryr.long-morgan9704]

Thanks for sharing. So, You recommend usong the extra thin over the reg. thin? If I'm converting a 4 door to 2 door, would You suggest a fairly thick solution to cover up original scribe lines? Thanks /Rosemary

[@HearnsHobbiesMelbourne]

Thank you for watching! Try sprue goo for filling in panel lines and joining reconstructed bodywork. Here is a tutorial: kzbin.info/www/bejne/l4WXY5KldreJask

[@djawda]

Hi what plastic did you usiedli becouae i put difrent plastic and it doesn’t melt :( 😢

[@HearnsHobbiesMelbourne]

The plastic must be polystyrene, such as the material in plastic model kits.

[@chrisclifford4529]

Hi when you cut the figures for remodeling, what is the best way to cut without losing too much material. Thanks, Chris....

[@HearnsHobbiesMelbourne]

Thank you for watching! The cleanest cuts are achieved with very thin and fine saws such as the Tamiya photo-etched ones www.hearnshobbies.com/products/tamiya-fine-craft-saw-iii-thick

[@chrisclifford4529]

Thank you so much. It's really appreciated. @@HearnsHobbiesMelbourne

[@gsr4535]

Thank you! I never knew!

[@HearnsHobbiesMelbourne]

You are so welcome!

[@countmacula530]

Really useful. Thank you.

[@HearnsHobbiesMelbourne]

Glad it was helpful! Thanks for watching!

[@hugosinnicks]

Can you use sprue goo with Blue stuff?

[@HearnsHobbiesMelbourne]

Yes, you can. Anything can be used as nothing will stick to the Blue Stuff, except more Blue Stuff or silicon. Be aware that sprue goo takes some time to set so be careful that the sprue goo isn't too thin as it may drip out of your mold during curing.