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View Full Version : Thermite wont ignite


Dodoman
August 27th, 2004, 01:40 PM
I've made thermite and it won't ignite. This is my first time making it. I used Fe2O3 and Al with ratio 80:27 respectivly according to the reaction Fe2O3 + 2Al ----> Al2O3 + Fe.
I mixed them in a morter. I used a magnesium strip it didn't ignite. I've tried placing some of the powder on the strip it ignited with a spark but didn't ignite the rest of the powder. I used KMnO4 and glycerol, the glycerol ignites vigrously but still won't ignite the thermite mixture :( . Can anyone please help me with this.......? Any reply would be appreciated.

Cemist
August 28th, 2004, 03:15 PM
I usually take a bit of the thermite and mix it 1:1 with Mg powder and this mixture is then ignited with BP/Mg and a simple visco fuse and ignites the rest of the Thermite.
Never had a failure with this method.

An other method would be to take commerial available thermite igniters which could also be homemade by mixing
53 % Ba-Nitrate
20 % Al-Powder
15 % Iron(III)-oxide
12 %Dextrine
with water to a sticky paste and proceed with it like you would for making sparklers.

Hang-Man
August 28th, 2004, 11:18 PM
Theres other threads on thermite, and this will most likley be deleted, but try adding some KNO3 to the mix and useing KNO3/Mg to light it.

croc
August 29th, 2004, 12:08 AM
I have had the exact same problems as you and tried to ignite it in the same order. The bad part is mine failed also. Your problem might be that the Al is not fine enough. Is it a powder or filings?

K9
August 30th, 2004, 02:19 PM
There's a good chance that the powder isn't fine enough which would prevent ignition of the mixture. If that's not the problem, then the only solution I can see is either sensitizing the thermite to ignition by addition of something like magensium powder, or just using a lot more of whatever the ignition material is.

chemoleo
August 30th, 2004, 02:35 PM
A sparkler, or two. I have yet to make a thermite that CAN'T be set off with sparklers.
Be careful though, some thermites are sensitive to sparkles coming off (i.e. CuO/Al), so you might get premature ignition. In that case, just tie them together lengthwise, to make sure early sparkles can't reach the mix. But in fact, CuO/Al can be ignited by burning paper anyway, if your grades are good enough.

JimmyJones
August 30th, 2004, 05:30 PM
I always use sparklers to set off thermite and it works 100% of the time. I would advise you give this a try and also check to see how fine your power is since this reaction requires the powder to be pretty fine.

NiteRider13
August 31st, 2004, 10:34 PM
odd,
Are you sure your Al is pure and not alloy, Could it possibly be coated. All the thermite I have made, usually had pretty course Al and I've had zero probs igniting it. Also the commercial welding thermite I've use also had fairly large mesh Al.

Nite

Dodoman
September 15th, 2004, 09:08 AM
My Al is very fine and the ingredients are dry. I've maneged to ignite it ayway thanks for the help. To ignite it i used KMnO4, glycerine and magnesium strips. I placed the strips on the thermite and the KMnO4 over it and dripped the glycerine. The heat was enought to burn the whole thing unlike when using one strip that heats only a small portion of the thermite.

nitroglycerin226
September 7th, 2005, 07:49 PM
I know that this is an older thread, but I am having problems lighting various thermite reactions. I am testing MnO4 thermite, CuO thermite, and Fe2O3 for the potential production of nanoparticles. I have lab grade oxides and aluminum. The aluminum is 100 mesh, and the oxides are fine powders. I have tried Magnesium ribbon and have gotten limited results. The same is true for a KCLO3/Sugar mix ignited with concentrated H2SO4. From each I got only one reaction after at least 20 attempts, and both were with CuO thermite. Is there a method of ignition that is extremely reliable? Or are there other chemicals that can be added to increase the sensitivity the reactions. any help would be greatly appreciated.