Intro: Lead Pig for Radioactive Samples
how to build a lead pig
Step 1: Items Required
roll of roofing lead (code 4) scissors , duct tape, crisp tube, postal tube, glue pen, knife
Step 2: Rolling the Lead
Roll the lead around the crisp tube fairly tight, measure enough so that you have a slight overlap of 6 turns making sure if you choose say 6 turns that you have enough lead left to make 12 quantity discs to cover each end ( 6 discs each) to match the quantity of turns ,don't worry that the tube does not slide out afterwards due to the metal end pieces being a bigger diameter, they will be cut off afterwards, once you are happy with the rolled up lead you can tape it with electrical tape to hold it if required .
Step 3: Cutting the Crisp Tube
Cut the crisp tube while in the roll of lead, use a marker pen to mark one end then push the tube out a bit then use a knife to cut round the mark then do the same for the other end , save the bottom end piece for a cutting template for the end pieces.
Step 4: Cutting the End Discs
now cut 12 discs , 6 for each end , more if you want a thicker lead shield I made mine with 6 layers due to the size of lead I bought, using the rolled up lead place it end down on the remainder of lead using a marker pen to mark a disc template, do the same for the other discs.
Step 5: Cutting the Postal Tube
marking the length of the postal tube requires measuring the total length of the lead roll including the end cap discs you have cut, I found it best to cut a bit longer, it can be cut down later.
Step 6: Making the Discs Fit Into the Postal Tube
now check the discs will fit into the postal tube, does not matter if they are a bit tight, as long as the lead stays flat, now using the crisp tube end you saved you can mark some plastic tape to stick on the lead end that will be facing inside the tube.
Step 7: Glueing the End Discs in Place
now slide the the tube over the lead roll making sure you have the six end pieces in the bottom end facing down before inserting the first disc in the top , when you are happy that the tube is covering all the lead pieces including the roll, you can glue the first end disc in place , making sure you do not glue the end disc to the main roll of lead, only glue to the postal tube then glue the rest of the discs in place , if the tube over hangs the top disc cut some cardboard to pack to make it level, now slide the postage tube off the main roll of lead leaving the end discs that you have glued in place.
Step 8: Cutting the Tube in Half and Glueing the Remainder Discs in Place
now cut the tube in half about 60 % 40 % from the center , having the end with the discs in at the 60% end, now slide the tube over the roll of lead, now slide the other tube over the remainder of the lead.
Step 9: Glueing the Other Discs in Place
now with the open end tube facing up insert and glue the other discs as before making sure there is a gap between where the two tubes meet so that the lead end discs meet the lead roll before the postal tube halves meet, you will have some over hang of the postal tube from the last disc ( can be trimmed off at the end.
Step 10: Finishing the Tube
now glue the cardboard end piece to cover the last lead disc showing, making sure the 40% tube end can still be pulled up ( not been glued to the main roll of lean) and has a gap between the both halves of postal tube, when you are happy with the fitting you can now glue the roll of lead 60% tube end, now slide in the crisp tube.
Step 11: Tube Before Covering With Duct Tape
the tube should now look like this I did cover the end of the lead roll with electrical tape but decided to remove it , so that the lead roll makes better contact with the end discs.
Step 12: Covering With Duct Tape
now with the two halves pushed together , cover the side with duct tape , it is ok to go over the join of the two halves, this can be trimmed after, leave enough tape to fold over the end of the tube can be tidied up when you cover the ends with with duct tape. you can now cut through where the two halves join with a knife then trim once the two halves of the tube have been pulled apart.
Step 13: The Finished Lead Pig
now you can safely store your radioactive samples, I store pitchblende in mine , I have now reduced the level of the radioactivity from 50 microsieverts down to 1.5, the lead roll measures 210mm x 3m, code 4 (1.8mm thick)
it weighs 13 kg.