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1.3 Cake Inserts


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Hey guys.

Ive posted a similar topic in the past, and ive been playing with custom cakes on and off. When I have the time I don't have the motivation, when I have the motivatin I don't have the time.

Let me start by what I want.


About 75 shots

All big breaks and salutes



Mostly brocade (I have a nice formula that's similar)


Well I guess I want a basic 12 shot 500gram consumer cake, with salutes, but larger.

I just took apart a 500 gram cake, as mentioned above, to look at their inserts.


Its about three inches tall, 2mm wall.


But what im not sure about on my behalf, is ramming both ends with clay. As they have done. This worries me, because mine will be broken with slow flash (50 p. Nitrate 25 German Dark 25 sulfur)

Maybe some hot flash, maybe some breaks with an antinomy powder flash if anyone knows of a good crack sounding formula.


If I make a slow flash break....is it safe to ram a closing end of the insert? Or press?


I noticed they used red clay also. I have bentonite, and im not confident in it. Their red clay is course like kitty litter, which seems to fit nicely ...any sources for a pound or 2?


My cannons are from Yazoo mills, and have passed a safety test launching 1 instert with 10 grams of hot b.p. However they are on the slender side with wall thickness.


If anyone has a good tutorial for the actual inserts, id be greatfull, or even some good advice. Thanks a lot guys.


BTW....I think this red course clay with help with a lot of my problems and confidence. I cannot drill the bentonite for a fuse with out it crumbling.


Thanks a lot guys.


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I definitely wouldn't ram them if they contain any type of flash. Perhaps you could use a bit of NC lacquer to waterproof the flash then use Durhams rock hard water putty. Someone else is likely to have a better suggestion, but this is the first thing that came to my mind.


Edit: I don't know if this helps, but I just came across this post by Leedrill. Maybe it'll offer some insight.


ok so my post is in hope to inspire a good thread compiled of the best cake insert methods you have all seen or used


i will say ive never pulled a commercial one apart but have seen some made {it appears in vids } timed by slurry inserted with a pastry piping bag


now along with people posting the methods they have seen id like to ask is there a strobe comp that can be used as a slurry {safley} in the method i suggested


so my ideas so far for what id like to make is a 1" to 2" inserts cake


tube plugged one end with bentonite then insert the {what seems to be the widely used method of stars with prime and rolled in slow kno3 flash to conserve space } bulk filled with granulated bp


then to plug with end caps with a piece of visco in the centre with a hollow rammer only as a pass-fire and a cap


then to paste over this to the intended size and for more confinement


then fill the space in the end over the visco with bp slurry {preferably with nc lacquer for obvious reasons }


the mix will need to be perfected due to shrinkage but nc should solve most of this


this slurry will act as a spoolette timing for the insert


and the right thickness of endcap used with the visco and the right thickness of bentonite and pasting will determine even breaks { well as even as a good quality commercial insert anyway }


now my thought is to use a pressed strobe comet placed in the cavity so pipette some slurry in to just cover the visco passfire section and then place in a pressed strobe comet or a matrix comet with DE in them and then fill the rest with the pipette of slurry


and dust with granulated bp to prime then put lift underneath and time the cake


what is everyones thought on those method i cant really find much good info out there for quick production of them id find this method really easy


please let me know your thoughts


Edited by BurritoBandito
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I have always been happy using good quality card end disks, and two layers of well pasted paper to seal the gaps for either the top end (if the other plug is rammed clay) or even for both ends.


I can't deny I've used hot glue too, though 1" is getting on the larger size for this to be cheap. In both systems the priority is really for it to be sealed from lift, which is why I want to emphasize getting the paper well soaked in paste and making sure it is soft and lays down well. It can't hurt to paste a layer of paper over a hot glue plug.


If your bentonite is not filing you with confidence, and you describe the Chinese clay as both what you want and like cheap cat litter... what about cheap cat litter? Or if you have a good supply of spent cakes, you could harvest the genuine article through some TLC with a sledge hammer.


While ultimately if it works for you, that is all it needs to do, and there is definitely no need to make the fastest BP, ten grams for launching a 1" insert is definitely quite a lot, and if you can get away with less that will definitely stress your inserts less. Or do you mean you used 10g to check that it can handle excess?

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You can get the red clay as modelling clay (most times it wet and need drying) from a pottery supply store.

This clay breaks appart easy, just ram one side , drill a hole, fuse it and fill with stars. Use ffg and about 0.5-.7g of kno3 flash as break and top up with a disk. Now you glue in either clay plug, which gets meda like a pumped star, plug with hotglue, glue in about 2-3 end disks or just close with and paper end plug and done.

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The red clay you see in Chinese product is just their soil outside the factory. I could not tell you exactly what type of clay it is.


For inserts, many cakes just use small ball shells. Obviously they use some small cylinder shells as well. The Excalibur type cylinder shells have thick clay plugs and are pressed with burst and stars in the middle. Do not ram anything boosted with flash or whistle. I would use paper and paper discs rather than worry about copying the method with clay plugs.

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I Seal one side of the bombette with clay( that's the side where you'll insert the fuse) using a homemade tool ( it has a rammer and a spindle) then add the stars ( I use 3/16" stars and fill up the tube about 3/4 full) and flash ( I use between 1.5 and 2 grams of slow nitrate flash with nice results kno3 50, Al (-325) 30, S 20, I use eckart 10890) once I got everything inside I just place a small piece of tissue paper on top of everything and then I just seal the other end with hot glue









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