mpguy80/08 Posted May 24, 2012 Share #1 Posted May 24, 2012 Hi Gang... I recently picked up a tin off Ebay that to be honest, I never thought I'd have won but as luck would have it, I pulled out the score. I have a rather extensice Demolitions display and thought the tin would go really well with the display. The tin is a carrying case for the Switch No. 10 Time delay detonator. To give you a bit of historic reference, we all know that Von Stauffenberg tried to kill Hitler with a briefcase bomb, right? Well, the explosives were reportedly british in origin and the detonator used was the Switch No. 10 Time delay detonator. The Switch No. 10 Detonator was also called a "time pencil" detonator. The tube was a two part tube, with one end a fairly sturdy Brass or aluminum with the other end a crushable thin copper tube. Inside of the Copper end of the tube was a vial of Cupric Cholride. That end of the tube was sealed with a plug and slot head screw which held a lead wire. the lead wide was routed past the glass vial of cupric chloride to a spring loaded striker device. At the aluminum end of the tube was a percussion cap, and threads for a fitting for a number of devices such as a blasting cap, det cord, time fuze etc. Crushing the copper end would crush the cupric chloride ampuole, starting the reaction between the cupric chloride and the lead wire. The time delay is dependent on the percentage of the solution of cupric chloride. The stronger the solution, the quicker the liquid qould eat through the lead wire, causing the wire to snap and the striker to activate. Time pencils came in various time delays from one hour to 24 hours. The safety strip is color coded to identify the delay time of the pencil. BLACK: 10 Min., RED: 30 Min., WHITE: 2 Hrs., GREEN: 5½ Hrs., YELLOW: 12 Hrs., BLUE: 24 Hrs. Five time pencils can be carried in the carrying case tin and are usually all of the same time delay. To use, determine how long of a delay you need before you want your explosives to explode. Select the proper time pencil. A blasting cap may be inserted into the adapter on the firing end of the pencil. You may also use time fuse inserved into the adapter on the time pencil with a blasting cap crimped to the end of the time fuse to give an added safety measure. There are two holes in the firing end of the pencil. The one closest to the firing end contains the safety tab. The other is an inspection hole. If you look into the inspection hole and can not se straight through, the lead wire has either broken or the cupric Cholride ampuole has broken and eaten away the wire. If so, the time pencil can not be used. If the safety tab were withdrawn, it would instantly fire. Once you've chosen your time pencil, insert the desired length of time fuse into a non electric cap and crimp the cap to the time fuse. This will give you a safety margin in case the time pencil fires as soon as you pull the safety tab. Insert the loose end of the time fuse into the adapter of the time pencil. Once your charge is prepped, arm the time pencil by crushing the copper end of the pencil, crushing the cupric chloride ampuole. The cupric chloride reaction begins, slowly eating away at the lead wire holding the striker under spring tension. Observe the safety tab and inspection holes. If the striker can not be seen in the inspection hole, insert the cap and or detonator into the explosive charge and remove the safety tab. The charge is now primed to explode after when the time pencil activates the percussion cap. I had the tin... now I had to figure out how I was going to come up with a suitable facsimilie of a Time pencil. A trip to the local Lowes provided everything I needed in the plumbing, electrical and hardware departments. I got some 3/8ths inch copper tubing from the plumbing section. Five feet was about eight dollars. a small bag of slot headed screws from the hardware aisle and a small container of different sized crimp connectors from the electrical dept to mimic the adapter on the end and I was ready. I straightened the copper tubing and cut it into sections approximately 5-1/8ths inch long using a tubing cutter. The time pencil can be no more than 5-7/8ths inch total length when it is complete or it wont fit into the carrying tin. I used a flat board to roll straighten the sections to get them as straight as I could then I superglued the screws into one end of the tube. moving to the other end of the tube, I carefully drilled the safety and inspection holes, with the closest hole no closer than 3/8ths of an inch to the end of the tube... Using a pair of heavy duty wire cutters, I clipped the aluminum forks off the end of the connectors as the forks would interfere with the inspection and safety holes. I inserted the tapered ends of the connectors into the end of the tube and twisted a little to get them to seat, then super glued them into place as well. I painted the adapter ends black, and painted the firing end of the tube aluminum 2-7/8ths of an inch up from the firing end of the copper tube. I left the remainder of the tube in it's natural color and took a thin strip of electrucal tape and wrapped the junction of the aluminum paint and the copper color of the tube. the adapter end piece isnt long enough to cut the proper cut outs so I settled for one of the two openings on the actual item. The safety tabs were cut and folded from an aluminum soda can, painted and inserted into the safety hole. I will probably go back and refabricate these out of styrene tubing at a later date, but the results aren't too bad as you can see. The hardest part of the whole adventure is drilling the safety and inspection holes in the copper tubing without tearing the tubes up. Go slow and make sure you are using a metal cutting bit in your drill. Don't push too hard either or you'll deform the tubing. Let me know what you think! Wayne Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 24, 2012 Author Share #2 Posted May 24, 2012 The finished time pencils.... Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 24, 2012 Author Share #3 Posted May 24, 2012 Actual photo of a sectioned time pencil showing the component parts... Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 24, 2012 Author Share #4 Posted May 24, 2012 Maybe I should have dropped this into the "Show some Imagination" Thread, eh? Link to comment Share on other sites More sharing options...
Johan Willaert Posted May 24, 2012 Share #5 Posted May 24, 2012 I was just about to post a picture of an original one, but realized that then I would have to send you some and since I don't have any spares, I can not do that.... Just kidding, Wayne, Great Job! Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 24, 2012 Author Share #6 Posted May 24, 2012 I was just about to post a picture of an original one, but realized that then I would have to send you some and since I don't have any spares, I can not do that.... Just kidding, Wayne, Great Job! LOL!!!! I figured right off the bat that finding one of these would be like finding the holy grail... so I made my own. Improvise and overcome!!!! I found somewhat of another holy grail today too... Watch the finds and aquisitions later for pictures... Wayne Link to comment Share on other sites More sharing options...
Johan Willaert Posted May 25, 2012 Share #7 Posted May 25, 2012 For reference this is an original US M1 Type Delay Type Device, similar to the N°10 For safety reasons, the firing pin wire and cap have been removed... Box originally held various colors, but was changed to BLUE only... Link to comment Share on other sites More sharing options...
capajo02 Posted May 25, 2012 Share #8 Posted May 25, 2012 Wayne, These look great for homemade items. I skimmed through the thread to look at the photos - like an impatient kid - and initially thought you have purchased an original tin filled with original time pencils. I sent you a PM with a couple questions. Thanks, John Link to comment Share on other sites More sharing options...
plick27 Posted May 25, 2012 Share #9 Posted May 25, 2012 Wasn't sure how those Sta-kons were gonna fit in till I looked at the next picture. Would have never pictured them looking as good as they do. Awesome job of using some varied materials to end up with a damn good representation! :bravo: Link to comment Share on other sites More sharing options...
paul_bish Posted May 25, 2012 Share #10 Posted May 25, 2012 very nice. I think I will make some of these for my demo kit used on our display. Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 26, 2012 Author Share #11 Posted May 26, 2012 Thanks guys.... I've been busy all week preparing for the Patriot Freedom Festival at the Dayton Ohio VA on saturday. Ingenuity is the mother of all invention... =) The time pencils will go on display for the first time this weekend along with my home made det cord reel... We'll see how it goes. Wayne Link to comment Share on other sites More sharing options...
mpguy80/08 Posted May 26, 2012 Author Share #12 Posted May 26, 2012 For reference this is an original US M1 Type Delay Type Device, similar to the N°10For safety reasons, the firing pin wire and cap have been removed... Box originally held various colors, but was changed to BLUE only... I guess I could call them M1 Delay firing devices, couldn't I? heh... imagine that. Link to comment Share on other sites More sharing options...
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