asilentbob Posted August 16, 2009 Posted August 16, 2009 There were about 6 box type plunger boxes, about 6 twist type, 2 clackers, and 1 clacker style continuity checker at the PGI trade show this year. I ended up getting a small modern CD box. I think a cool project would be to build a small plunger type box into an army ammo can somehow.
Arthur Posted August 26, 2009 Author Posted August 26, 2009 OK I have a semi derilict plunger machine. Has anyone any real drawings of how it should be wired inside? There seem to be bits missing! Notably the brass bolts so I don't know what wires should go where! The generator spins and the contacts open as the rack hits the bottom, strangely only one side of the contact breaker has a wire attached!! In the UK it's the highlight of the bride's night if she can push the plunger! Better than chocolate or red wine!
Richtee Posted August 28, 2009 Posted August 28, 2009 OK I have a semi derilict plunger machine. Has anyone any real drawings of how it should be wired inside? There seem to be bits missing! Notably the brass bolts so I don't know what wires should go where! The generator spins and the contacts open as the rack hits the bottom, strangely only one side of the contact breaker has a wire attached!! In the UK it's the highlight of the bride's night if she can push the plunger! Better than chocolate or red wine!Soo install a microswitch inside, run the leads out to bolts you install and use it.
Arthur Posted August 28, 2009 Author Posted August 28, 2009 (edited) One of the interesting features of the old pattern "Blasting Machine" is their ability to function for years without attention. Which has to have a LOT in it's favour! Added; I've just been out and bought some brass bolts and wing nuts, and the machine fired a cap first time. It's 50+ years old and still works perfectly. Now to renovate the case. Edited August 29, 2009 by Arthur
Swede Posted August 29, 2009 Posted August 29, 2009 They don't make stuff like that anymore. Consumer products are getting so shoddy; everything is "disposable" now, you just buy a new one. I don't mind the availability of cheap crap, but I'd like to have the choice of paying extra for items built like a tank. Unfortunately, high quality stuff is so rare because they are not competitive anymore. Old man Grumble... http://4.bp.blogspot.com/_7Q-tD8eW2rE/Se9XyXctHyI/AAAAAAAACvY/_pCTgUJR2Io/s400/old-man-with-cane1.jpg
Richtee Posted August 30, 2009 Posted August 30, 2009 I've just been out and bought some brass bolts and wing nuts, and the machine fired a cap first time. It's 50+ years old and still works perfectly. Hey I'm 46+ years old...and while the case is a little dinged up..I still do OK too
Swede Posted August 31, 2009 Posted August 31, 2009 Ah, remember a double-dip Baskin Robbins ice cream cone for 30 cents? Or your Dad pulling into a service station, and three dudes run out to check oil, clean windows, and fill the tank, for 40 cents per gallon, while the old man hands cash through the window? I do. Old (middle-aged, whatever) people UNITE.
TheSidewinder Posted August 31, 2009 Posted August 31, 2009 Ah, remember a double-dip Baskin Robbins ice cream cone for 30 cents? Or your Dad pulling into a service station, and three dudes run out to check oil, clean windows, and fill the tank, for 40 cents per gallon, while the old man hands cash through the window? I do. Old (middle-aged, whatever) people UNITE. Errmm... I remember being old enough to hand the attendant the cash for 40-cent/gallon gasoline myself, let alone watching Dad do it. And although I don't remember the price for a double-dip Baskin Robbins, I do remember going there as a young boy. Dad made it a habit every Sunday after church. At the time, my favorite flavor was Mandarin Chocolate Sherbet. P.S. Sorry for hijacking your thread, Arthur.
Arthur Posted August 31, 2009 Author Posted August 31, 2009 If it wasn't for us oldies the kids wouldn't have a college to go to instead of working. In my youth I remember flying a Piper Twin Commanche into Heathrow at 0730. You cannot do it now because they charge soo much for the landing slots that only the big passenger planes go in for their 450 pax at a time.
TheSidewinder Posted September 1, 2009 Posted September 1, 2009 We're mind-wandering again, Arthur. Yeah, I remember when *any* GA (General Aviation) aircraft could land at KMSP. Even a Piper Cub. But no longer, regardless of anyone's willingness to pay high landing fees. And they ARE very high. GA aircraft these days fly into KSTP (Holman Field, St. Paul), KFCM (Flying Cloud, Eden Prairie), or KMIC (Minneapolis Crystal).
tentacles Posted September 2, 2009 Posted September 2, 2009 To bring things back on subject, my wife was privileged to use one at PGI on friday night; we were at the hanging salute range and they were getting ready to flatten the frames and call it a night. asilentbob was awesome enough to let her blow it up, and it was great.
Arthur Posted September 2, 2009 Author Posted September 2, 2009 Which is exactly whhy I want one for the Bride to start her wedding fireworks.
Swede Posted September 7, 2009 Posted September 7, 2009 (edited) When I was looking for them on eBay, any of the functional old units was fetching $300 minimum, and the nice ones were $400+. An alternative - there are old telephone crank generators that have guts very similar to these blasting machines. Here's one, but on examination, it might be missing the guts on the rotating part. I don't know enough about them. But there are many others. Each of them has a large gear turning a smaller gear, which generates the voltage. Removing the large gear and attaching a plunger rack to the small gear would generate 60 to 100 volts with ease.http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...em=260470592764 Something like this might be adaptable at 1/10th the price. Oh yes, my bicycle generator idea was ludicrous. Not nearly heavy enough. Edited September 7, 2009 by Swede
Arthur Posted September 7, 2009 Author Posted September 7, 2009 OK some DC rotating machine theory for you. I've studied the works of one of these blasting machines. The important aspect is that they only fire as the rack hits the bottom stop. They are a particular type of generator, they start with the rack up as a shunt unit simply the armature spins, creates current which flows through the field windings increasing the magnetic flux, increasing the current. As the rack hits the bottom stop it opens a switch, this forces the circulating current to pass theough the igniters. The significance of this is that the igs get a good full current not a half size pulse.
Swede Posted September 10, 2009 Posted September 10, 2009 That's interesting... I never would have expected it to work that way. I would have thought the current would begin to flow immediately and simply peak at the maximum velocity of the armature. It makes me think of the use of a capacitor might be a way to make a modern, mechanical blasting machine. A spark coil for an engine might work in a similar way. A spark coil has a primary wind which is energized, and when the point (switch) opens, and the primary coil dumps its energy into the secondary, which can be thousands and thousands of winds of very fine Cu. The voltage is boosted to 10,000V or so. Cool stuff.
Arthur Posted September 10, 2009 Author Posted September 10, 2009 There is a critical characteristic of commercial fuseheads be they for pyro or blasting, They hava a no-fire current say typically 20mA you can pass that for hours without a fire. They have an all-fire current usually in the order of 500mA (though check the data for the type you are using) This means that at 500mA all of a group of like igs will fire. The big problem is the in between bit At 20 mA none fire but at 50mA or 200mA some igniters could fire leaving others unfired. Unfired igs mean unfired fireworks meaning that in the dark after a show you have to go up to a failed firework and clear it which is dangerous -it also means a failed cue in the show. If the current supplied ramps up over say 30 mlliseconds then some igs will fire and some NOT. IF the current is supplied as one huge pulse then all the igs will fire together. I tried a GB telephone generator from a hand cranked bell system, though the meter said 200VAC once you load it with an igniter then nothing happens the generator is not powerful enough If anyone has a small universal electric motor then possibly this would work BUT I give no promises.
mike_au Posted September 11, 2009 Posted September 11, 2009 I tried a GB telephone generator from a hand cranked bell system, though the meter said 200VAC once you load it with an igniter then nothing happens the generator is not powerful enough I think someone nailed this on the last page, stick a cap (and rectifier) across it and only connect the cue as the plunger hits the bottom.
asilentbob Posted July 14, 2010 Posted July 14, 2010 To bring things back on subject, my wife was privileged to use one at PGI on friday night; we were at the hanging salute range and they were getting ready to flatten the frames and call it a night. asilentbob was awesome enough to let her blow it up, and it was great. Not my plunger, one of the ground salute range guys. But yeah it was a good time!
Arthur Posted July 15, 2010 Author Posted July 15, 2010 Yes a real one came my way with assistance (much appreciated -Thank You), and was used on this show, highlight of the bride's firework display was pushing the plunger! The first cue was two retail 3" mines a Pro 3" Ti salute and a strobe, all wired to one igniter, all fired by the bride in one push down! (all legal in the UK your laws may vary)!
xtr55 Posted December 14, 2011 Posted December 14, 2011 gunbroker has the old twist kind of blasters: http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264621858 http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264622032 http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264948772 http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264498185
xtr55 Posted December 14, 2011 Posted December 14, 2011 they carry old TNT boxes too if you wanted to use one to make your own http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264352570 http://www.gunbroker.com/Auction/ViewItem.aspx?Item=264296547
warthog Posted December 15, 2011 Posted December 15, 2011 (edited) I have one of those old twist ones here somewhere. Guess I should dig it out. Edited December 15, 2011 by warthog
Peret Posted December 15, 2011 Posted December 15, 2011 I've got a nicer dynamite box than the one on sale above. I found a pile of them in an abandoned mine in good condition, along with picks and drill steel. I didn't find any plunger blasting machines, though. I saw one in a junk shop once but didn't buy it at the time, went back a few days later and it was gone.
warthog Posted December 15, 2011 Posted December 15, 2011 (edited) The first cue was two retail 3" mines a Pro 3" Ti salute and a strobe, all wired to one igniter, all fired by the bride in one push down! (all legal in the UK your laws may vary)! Nice display and I bet the plunger went over well too. The one you wound up with looked pretty nice to boot. ======================================================================================While these are not the best pix of it, this is the twist type unit I have. This was one of my uncle's who work in Arizona in a copper mine as one of the guy who blasted sections of the pit's wall out. I have never used it but it was operational when he brought it home after his retirement in the early 70's (may have been earlier than that as I was a little shaver at the time and don't really remember clearly). I don't even know how to hook it up properly. It would be a cool way to set off a finale though. Edited December 15, 2011 by warthog
Arthur Posted December 15, 2011 Author Posted December 15, 2011 For the show I did with that plunger box, firing the show herself probably doubled the brides perceived value of the show. It is however lawful for the bride to do this in the UK, please check with your statutes before you try it.
Recommended Posts