Independance red

[dynomike1]

I just made 3 i lb batches of independence Red and the best i can get is orange and it doesn't want to burn either. Does Strontium Nitrate go bad? It's in its original bag stored in a bucket with a lid.

 

Strontium Nitrate 50

 

MGAL 15

 

Parlon 16

 

Dextrin 5

 

Red Gum 10

 

Ok i swapped the Strontium With Barium and still got the same thing

Edited January 19, 2018 by dynomike1

[stix]

I wouldn't think that Strontium Nitrate goes bad - I hope not because I've got some in storage.

 

This is the formula I've used (with great success) for Red Nitrate Rubber Stars:

 

Sr[NO3]2 53

MGAL 19

Parlon 17

Red Gum 11

 

The above formula doesn't use Dextrin.

 

From memory, when Dextrin is used, it's used as the binder and activated with water. Otherwise you drop the dextrin and use Acetone or (MEK). I'm no expert, so hopefully someone can expand on this.

 

This is what I wrote down as the results:

 

These stars work fantastic. Brilliant and strong Red.

 

Cheers.

Edited January 20, 2018 by stix

[dynomike1]

I have used this formula for 4 yrs. and never had a problem. It's not the Strontium i dont think, but now seems like something else is the problem. You just dont miss mix a formula 3 times.

[stix]

Weird.

 

Well, take it back to basics. if you've used your formula for 4yrs with success, then track it back. ie. what have you changed recently?

[MrB]

Since you swapped for Barium Nitrate, and it did the same thing, it seems unlikely, but they are both hygroscopic to some extent... Sure the stars are dry? Try drying a bit of nitrate, and excluding the dextrin, and do the "normal" rubber stars variant, with acetone, to see if that helps?

[dynomike1]

Stix nothing i can think of. I made some with the same chems last year.

Mr B i am working on it

[stix]

"Rubber" stars do not need to be "dried" - they are "set" through evaporation of the solvent, ie. Acetone or MEK - it's a reasonably simple composition.

 

Fair enough, I've likely extended the limits of my understanding of chemistry BUT my evaluation scenario holds true:

 

If it doesn't work, then go back to the drawing board, take simple steps one at a time, and you will find out soon enough where the issue is. Basic trial and error.

Edited January 20, 2018 by stix

[dynomike1]

I agree Stix but looks like Mb won the cigar. I dried my strontium mixed it and worked fine.

[stix]

No cigar? It was never a race. I'm glad you got it sorted.

[MrB]

"Rubber" stars do not need to be "dried" - they are "set" through evaporation of the solvent, ie. Acetone or MEK - it's a reasonably simple composition.

 

Fair enough, I've likely extended the limits of my understanding of chemistry BUT my evaluation scenario holds true:

 

If it doesn't work, then go back to the drawing board, take simple steps one at a time, and you will find out soon enough where the issue is. Basic trial and error.

 

My point was that with the 5% dextrin he has, he was likely binding them with that, and using water. Scrapping the dextrin idea, and drying out the nitrates, and then going straight for the acetone should work. But that also means, it "should" work, if he did bind the earlier ones with water, and simply dry them out well enough.

If you have moisture in both the dextrin, and the nitrate, and yet bound the stars as rubberstars, with the acetone parlon/pvc, then you pretty much cant dry the stars out at that point... It might be possible if you grind them down fine enough, but i'm not sure i want to mill a live star-mix. It might behave as slow flash, and not appreciate the milling action at that.

Anyway, as Stix said, just happy it got sorted.

[dynomike1]

I do burn test as soon as i finish the comp. If it doesn't burn then , it wont burn after pressing or how ever. It's just hard to believe my chems are damp.been stored the same as always. I am drying my strontium and re double bag and put a descent bag with it.

THANKS for all the help guys.

[fckiamdead]

I just made 3 i lb batches of independence Red and the best i can get is orange and it doesn't want to burn either. Does Strontium Nitrate go bad? It's in its original bag stored in a bucket with a lid.

 

Strontium Nitrate 50

 

MGAL 15

 

Parlon 16

 

Dextrin 5

 

Red Gum 10

 

Ok i swapped the Strontium With Barium and still got the same thing

I make alot of this formula.

Have you opened a new bag of red gum for this batch?

[dynomike1]

I think we have determined that my nitrate was damp some how. I am loading a video before i dried my nitrate and i think i might have one after.

Before

I dont have one after but it worked

Edited January 21, 2018 by dynomike1

[fckiamdead]

I think we have determined that my nitrate was damp some how. I am loading a video before i dried my nitrate and i think i might have one after.

Before

I dont have one after but it worked

Can you burn the stars on the ground whitout any "wood"?

[stix]

I think we have determined that my nitrate was damp some how . . .

 

Yeah, let's not go down that path again

 

Dyno, I noticed in the above test that there is quite a lot of black smoke. How long do you dry these stars? Also I noticed at the end of the test all we got was a Hmmmmm. I would have expected a "Well, well, well - isn't that a lot better!". [EDIT] Oh, that test was before drying the strontium - pls disregard above.

 

@ MrB. "My point was that with the 5% dextrin he has, he was likely binding them with that, and using water." That's a good point, if Dyno is using dextrin & water to bind the comp, then what difference would it make if the strontium was damp? because the comp is then whetted with water and the stars or pressed comets have to be dried out properly in the end anyhow!!

 

So Dyno, how are you binding these stars? Water or Acetone/MEK etc.

 

I'm confused - I hope Dyno has a whole box of them there cigars

 

[EDIT] My aplologies - for too many edits.

Edited January 22, 2018 by stix

[dynomike1]

Some i use Dextrin or Phenolic. At that point it didnt matter because the first batch was Phenolic,and that's where it started. So i changed to Dextrin because i am low on Phenolic, well Dextrin did the same thing. So i thought i did something wrong so i watched the third batch closely and the third batch the same. I then dried the Nitrate and now it works. I wish i had a video of the ones that worked on the board, but i didnt expect to work, but its pouring down rain now. Ok when I mix comp the first thing i do is burn some dry, if dont work then i cant see it working later. The video was as per NJ's request wetted and pressed nothing changed from the dry. That was a test to see if they would change after weted.I agree if they were weted and dried what difference would it make if the nitrate was damp. I am not anywhere close to a chemist. I forgot they were forced dried all day. Maybe this will help, if not just ask.

[stix]

I'm certainly no chemist either, but one thing I have learned is you have to take the time to let them dry. Perhaps even a week depending on the weather (humidity). I was surprised that you had a test comp up and running after just one day - especially if it was bound using dextrin and water.

 

Maybe it's not the so called damp strontium, but perhaps you are being too impatient and not giving it enough time to dry? We all have done that before.

 

Also you mentioned using Phenolic. So then you are using different things, ie. changing things. It's very hard to evaluate or drill down to where the issue is, if you are changing the components, even if it is just one.

 

I've learned this from basic problem solving. Change one, test, re-test, if it doesn't solve it, then change something else - not two at once. It makes it too hard to work out where the issue is.

Edited January 22, 2018 by stix

[MrB]

@ MrB. "My point was that with the 5% dextrin he has, he was likely binding them with that, and using water." That's a good point, if Dyno is using dextrin & water to bind the comp, then what difference would it make if the strontium was damp? because the comp is then whetted with water and the stars or pressed comets have to be dried out properly in the end anyhow!!

 

Which is why i suggested he excluded the dextrin, and dried the nitrate for a test batch. If it indeed is "not dry" that causes it, then just drying the batch he made with dextrin would make them work. If it is "wet" nitrate that is his issue, having it baked inside plastic wont let it dry out, so that isn't a viable solution, if he used solvents.

[stix]

Yep, you are correct MrB. Damp strontium nitrate or damp anything would be trapped if you make "rubber" stars - or use Phenolic as Dyno has said he has used. I was trying to point out that if you chop and change a recipe then it makes it harder to work out what to do if things go wrong. Consistency is its own reward.

 

So, as a matter of interest, why keep the dextrin in the composition if you are not binding with water? Does it also act as a fuel?

Edited January 23, 2018 by stix

[dynomike1]

 

After drying nitrate and dextrin as binder.

Edited January 25, 2018 by dynomike1

[stix]

Dry the Nitrate if you have to, drop the dextrin and use Acetone or MEK as the solvent to bind them. Much easier.

Edited January 27, 2018 by stix

[bengalPyro2000]

Which is used insted of Redgum

[stix]

Sorry, dunno what substitute can be used, but I'm sure there is one. I'm not sure how crucial Redgum is, although it's around 10% of the total composition, so it must have some significance.

 

Acting more as fuel than a binder in this composition I would think.

[OldMarine]

Phenolic resin can be substituted for red gum both as a fuel and as a binder. I use 83% phenolic to replace the gum in any comp that calls for it and use it to bind the comp as well since I can have rock hard ready to use stars in a few hours.

[SKC]

Hi Dynomike, May I substitute parlon with PVC & Red Gum with Shellac ? Because PVC & Red Gum is not available here.

If yes what could be the ratio?

Hi Dynomike, May I substitute parlon with PVC & Red Gum with Shellac ? Because PVC & Red Gum is not available here.

If yes what could be the ratio?