Making NC lacquer from ping-pong balls

[Terry C.]

This is a spinoff from the "Slow match" thread.

Disclaimer: The purpose of this topic is the discussion of the making and use of NC lacquer in the context of loading and firing muzzleloading artillery. If this thread strays off into the subject of pyrotechnics and fireworks, it will be out of the scope of this forum and will run afoul of the mods.

For the purpose of black powder cannon/mortar shooting, nitrocellulose lacquer can be used as a combustible adhesive. Primarily, in the making or modifying of ignition devices. Priming Visco fuse with 4F powder to make it take fire from slowmatch faster and easier is a good example.

Homemade nitrocellulose lacquer can be made from single-based smokeless gunpowder. From what I've read, this method yields the best product.

There is, however, another formula for making nitrocellulose lacquer that appears on YouTube and the web, where ordinary ping-pong balls are dissolved in acetone. It appears easy enough, and although the end product is inferior to the gunpowder version, the result is a completely usable NC lacquer that many swear by.

According to my research, modern ping-pong balls are made from celluloid, which is 75% nitrocellulose and 25% camphor.

Since ping-pong (or table tennis as it's more properly called) is not one of my usual passtimes, I started by going out and buying ping-pong balls. I would also need a small jar, so I bought a jar of babyfood.

After eating the babyfood (diced apples in white grape juice, yumm!) and cleaning the jar, I cut three of the 'SPORTCRAFT' brand ping-pong balls into small pieces and put them in the jar. I then added the acetone, two tablespoons (or approx 30 ML) per ball. The various recipes call for differing amounts of acetone, so I went with the least in the logic that it would be easier to thin a mixture that's too thick than vice-versa.

The three chopped balls and six tablespoons of acetone filled my midsized babyfood jar about 2/3 full. It would've been too much for one of the smaller jars.

All that's left to do now is wait. According to the YouTube clip, you can "shake it for 30 minutes" but I don't think that 30 minutes would be long enough to completely dissolve all of the celluloid.

I prefer just to let it sit overnight.

Tomorrow, I'll know how well the recipe worked.

[cannonmn]

Forgive me for being dumb but what will you use the laquer for after you make it?

[Terry C.]

I'll use it primarily as a combustible adhesive.

First project, priming Vis-Quick fuse for easier ignition with a linstock.

The Vis-Quick is very fast-burning, but can be a pain to light. A little FFFFg glued to the end will help.

After that, I have an idea about how to roll some straws for quills.

Then I have some other ideas.

-------
I've edited my first post to include this clarification.

[Terry C.]

I used some of the lacquer and some FFFFg GOEX to prime some pieces of Visco fuse for testing.

For comparison, I replicated an earlier experiment using white glue and FFFFg. The results I got then were not good. At that time I deemed them a failure but I decided to give it one more try.

The NC/FFFFg fuses were made by dipping, coating the wet lacquer with FFFFg, then two dips in lacquer to seal and waterproof the priming. I let each fuse sit for about three minutes between dips.

The others were made using the same method, but using white glue and no third dip.

I drilled a piece of scrap spruce to hold the fuses for the test, then it was out into the sun for a couple of hours to cure. The white heads are the NC coating, the black ones are white glue.




The results for the white glued fuses were, if anything, worse than the first time. The glue/powder mix is, for all practical purposes, fireproof. Only after the slowmatch completely burns away the mixture and gets to the actual fuse will ignition occur.

The NC/FFFFg fuses, on the other hand, ignited instantly. If the match touched the priming at all, it would bust into flames. In fact I'm not so sure it has to actually touch, the heat from the burning match in close proximity to the priming may ignite it before actual contact is made.

I had one of the fuses ignite the one next to it in the board, and they're about 1˝" apart!

I'll have to do some experiments on just how much heat it takes to ignite the priming.

I have this all on video, but it hasn't been edited or uploaded yet (that's a whole 'nuther story...). I'll put up a couple of clips when I have them ready.


I would call this phase of the experiment a success. Usable NC lacquer can be made from ping-pong balls and acetone. It's not difficult or dangerous, and it does have at least one bona-fide use in black powder artillery shooting. I plan to find others.

[jeeper1]

Very interesting. I'll have to try that myself. With my limited ability to stand and walk, the faster the fuse is lit the less pain I will experience.

[Victor3]

 You might try Devcon Duco household cement. It's an acetone base nitrocellulose glue.

http://www.tedpella.com/technote_html/14445%20TN.pdf

 A friend of mine who was into making fireworks turned me on to it years ago. I've used it to prime fuse and glue nitrated paper together for making paper cartriges.

[Terry C.]

Didn't know about Duco, I'll have to check into that.

One piece of advice I can give about the recipe above is: Don't use a babyfood jar.

The soft lining on the cap that takes the threads on the jar won't hold up. I'm going to have to transfer this mix to a better jar soon.

[Terry C.]

Video is up.

This first video is one of the white glue/FFFFg primed fuses.

I'd tried this before (one of my brilliant ideas) and it was an embarrassing failure. To be fair, and to remove the pressure of performing, and most of all to avoid the dangers involved in swapping fuses in a loaded barrel, I decided to give it another shot in a more controlled situation.

The results confirmed my previous experience, White glue and priming powder don't mix.

This was the fastest that any of these fuses ignited, and then only because there was less of the mixture on the head of this fuse for the match to have to melt out of the way. (Click the images to play the clips.)




On the other hand, the next video shows just how easy the NC/FFFFg primed fuses go off. I lit one fuse, and it lit the one next to it! And the fuses were at least 1˝" apart.




Pay particular attention to the smoldering white glue fuse on the right in the last clip. I'd tried, unsuccessfully, to light this fuse and finally gave up and moved to the next one. It smoldered for several minutes before suddenly igniting. If this had been a live-fire situation, it could have been ugly!

[Rickk]

The duco cement looks worth trying. However, I would water it down a bit first with acetone, as it is a bit thicker than you want when gluing 4F to a fuse end.

For what it's worth, if you don't enjoy the "giggling mad scientist  " aspect of mixing cool combusible materials together, you can simply buy NC lacquer from Skylighter already made in pint containers. It is a bit pricey at 25 bucks a pint though. You can make at least a quart of it yourself for about that same price. Plus, a pint is alot. If you already have some single based powder hanging around, making a few ounces at a time will set you back very little.

Terry, your experiments pretty much duplicate mine. I tried wood glue about a year ago and realized that wood glue is an excellent fireproofing, no good for fire passing.

[dan610324]

sorry if Im comming with an stupid question , but if you are using an slow match why then use an fuse ??
why not just priming with ffffg ??

[Terry C.]

1) Some of the vents are small, and difficult to get the priming powder into.
2) Loose priming powder in a vent is slower to burn than a quill of a piece of VisQuick.
3) Quills and VisQuick don't get loose powder all over the furniture.
4) I want to.

[Rickk]

stuffing a piece of fuse in the hole is just way easier and more predictable as well.

[Double D]

I don't quite agree with the idea fuse is easier and and more predictable.  We used fine grain smokeless powder to prime the vent when fring the cannons at SAMCC.  We would push the powder down the vent with the vent pick. The slow match had no problem ingniting the powder. and ignition was almost instantaneous.

http://www.fototime.com/6BC3E2816350F24/conv.wmv

[dan610324]

I prefer an early 1600 cannon with an vent you can put your thumb inside 
preferably both thumbs 
it reduces the recoil also 

[and7barton]

On a number of gun displays we used to prime the vent with loose powder and used a portfirewith a length of slowmatch gripped in its jaws. It's historically more correct for pre-friction fuse re-enactment, but rather more nerve-wracking as it's instantaneous !

[Terry C.]

Well, I must be doing something differently, because in my experience priming powder down the vent was not instantaneous.

More like a fuse burning down.

[GGaskill]

When I used 4F, the burn was fuse-like.  The coarser grades work better since the fire can get between the kernels faster.

[Cannoneer]

This may have been discussed here before, but I don't remember seeing it. I have only used fuse in my miniature cannons, for reasons that others have already given, namely convenience. What exactly is the physical reaction that is taking place inside the barrel when it actually fires? That's probably a little vague; so, I light my fuse, it burns down into the breech, you can tell when it has reached the black powder in the barrel and that powder is beginning to burn because it always builds pressure that then blows white smoke up out of the vent. Why is there always that pause from the time you sart to see the pressure blowing the white smoke up from the vent that's caused by the powder beginning to burn and the explosion that actually fires the gun? Does the burning powder have to reach a certain temperature before it conflagrates all of the powder?

[Double D]

Distance and resitance.  The puff of smoke out the vent has no resitance to it and has to travel a substantially less distance than the smoke coming out the muzzle.

[Cannoneer]

Distance and resitance.  The puff of smoke out the vent has no resitance to it and has to travel a substantially less distance than the smoke coming out the muzzle.

DD,

 Yes, the pressure of the gasses being formed by the burning powder is going to move in the direction of least resitance, which would be up and out the vent (at least in the first stages of the powder beginning to ignite in the breech of the bore). As the powder is transformed into gasses by its burning, the charge burning from the rear towards the front, the gasses created would form a pressure that was to great to escape only from the vent and the pressure would then find escape forward out the larger bore diam. of the barrel, driving whatever occupied the space in front of the charge out of the tube.

What I'm asking is why is there a delay in the dicharge of the gun when a fuse is used as the igniter? This is from Civil War Artillery, the Amunition page - Friction Primers: " When the lanyard is pulled, the serrated end of the priming wire ignites the friction composition, which in turn sets off the musket powder in the body of the primer, which flashes down the vent to set off the main charge. The effect is almost instantaneous." When I've seen cannons and mortars fired at reenactors events in person and on video, when the gunner snaps the lanyard it sure seems like the cannon discharges without hesitation. It can't have anything to do with the amount of oxygen thats available because it would seem to me that the friction primer would allow less oxygen to reach the bore than a fuse would. The only answer that seems feasible to me is that the FFFFg that's in the tube of a friction primer is burning at a far greater temperature than the lit fuse, and therefore the ignition of the powder charge is a lot quicker. The lit fuse must just set the powder smoldering before it reaches a high enough temperture to ignite the whole charge, thus causing that pregnant pause before the barrel actually discharges. 

[GGaskill]

The fuse has to burn the thickness of the barrel at the point it goes through before it can ignite the main charge.

[Rickk]

I agree with GG.... it takes time for the fuse to burn down thru the barrel wall.

I have used fast burning "4F coated scotch tape" quills and there is no delay. It just goes BANG the instant the quill lights.

[Cannoneer]

The fuse has to burn the thickness of the barrel at the point it goes through before it can ignite the main charge.

I agree with GG.... it takes time for the fuse to burn down thru the barrel wall.

I have used fast burning "4F coated scotch tape" quills and there is no delay. It just goes BANG the instant the quill lights.

I'm not saying that I think the cannon should fire when the fuse burns down to the level of the metal, of course the fuse has to burn down through the inside of the vent until the sparks reach the powder charge in the bore where the end of the fuse should be seated, and of course it's going to take a period of time for the fuse to burn that distance; the thicker the walls of the barrel around the breech the longer the fuse and the longer the time of it's burning.
Rick, as you say, "It just goes bang the instant the quill lights". From the few vids I've seen where quill was used to fire the gun, it seems the same as friction primers, it appears the gun fires almost instantaneously.
The vid below is terrible, both in quality and content, these kids are either extremely lucky or fortunately blessed because they managed to skirt disaster (this time anyway) playing with this pipe bomb posing as a barrel. The only reason I'm posting it is because it contains a slo-mo sequence that shows exactly what I've been trying to describe about the delay between the powder first igniting and the discharge of the gun when fuse is used as the igniter.

http://www.youtube.com/watch?v=yAZOmWrqKH4&feature=related

[Double D]

As I said.  Distance and resistance.  The puff of smoke/fire out the vent has no resistance to it and has to travel a substantially less distance than the smoke/fire coming out the muzzle.  The fire comes out the vent first because the expanding gases can escape the vent before the ball has cleared the muzzle.  As soon as the expanding gases clear the muzzle the vent gases disappear.


 That is pretty clear in the pipe bomb video.

[GGaskill]

I think what you're seeing in the slo-mo-shun is the difference between a very low mass object (the burnt fuse being blown out of the vent) going a short distance before exiting and a higher mass object (the shot) going a much longer distance before exiting, the exits being the point where you see lots of fire and smoke.  Through the vent, the powder gasses have little resistance while the shot has to be accelerated from zero velocity to the end of the bore for the bore to be cleared.

At least the children had enough sense not to stand next to the piece of pipe while it went boom.

[and7barton]

Well, I must be doing something differently, because in my experience priming powder down the vent was not instantaneous.

More like a fuse burning down.

Well, perhaps not instantaneous........ I recall it usually took just under a second. Barely time to move the portfire away from the vent. Maybe the diameter of the vent affected the speed.