This craft project is mainly about cutting paper and making inserts for a picture frame.
It will not provide significant protection from nuclear weapons, although it _technically_ does provide effective shielding for one square inch of your body against one subset of radiation.
It might also tell you something about gadolinium which is an interesting metal.
With international tensions rising, thought should be given to protection from a nuclear attack.
The effects of a nuclear detonation break down into four categories; blast, thermal radiation, ionizing radiation and residual radiation.
This project is concerned with the third of those, ionizing radiation, and specifically with the subset of that called neutron radiation.
Hiding behind a three ton block of lead might help, but that would be awkward to keep and handle. This instructable provides all the neutron absorbing benefits of three tons of lead in a convenient package, complete with clear instructions for use in an emergency.
Gadolinium is a rare-earth metal which has an extremely high neutron absorbency, some 300,000 times that of lead. This means that 10grams (1/2 oz) is the equivalent of three tonnes (6,500 pounds) of lead.
Should you not have any gadolinium in your workshop, then it can be obtained from a number of sources. I bought mine via aliExpress. A US-based supplier is RWMM. If you are going to buy some, I recommend getting it in a sealed glass vial with a protective atmosphere as the metal does tarnish in air (quickly in moist air).
For actual protection against nuclear attack, I recommend a deep hole a long way away.
FOR THE AVOIDANCE OF DOUBT:-
As stated in the original intro above, the effects of blast, flash, residual radiation, X-ray and gamma will _not_ be ameliorated by the use of this project. If you are near enough to a detonation to receive a significant neutron dose then you probably want to look at measures to protect against the other effects too.
Radiation (as implied by its name) radiates. Therefore only objects in the shadow of the shield will receive any protection. The gadolinium sample in this project is about 3/4" by 2" (2cmx5cm). Pick your favourite organ and hide that.
Acrylic sheet does not break easily when scored. Therefore removing the tube will take longer than you expect. Please allow for this delay in planning your response.
Step 1: Preparation and Draft Layout
I pulled the back out of the frame and then cut a sheet of scrap paper to fit.
I downloaded the "Ionizing Radiation" log from wikipedia and printed it out.
Various trial layouts were made, and when I was happy i typed up a couple of boxes of text and printed them out.
The URL in the attached file points to an FDA page which lists requirements for warning labels. All of the approved fonts were sans serif, so I wrote my text in Arial, which looks clean and official.
Step 2: Cut Out Prohibition Shape
Having splashed out on a compass cutter, there were two problems:- the internal circle is interrupted by the cross bar, and the centre of the circles is visible, so we can't have a pinhole in it.
I used a strip cut from a post-it note to act as a template for the cross bar, and put an ink dot on it to mark the centre spot.
The compass cutter came with a little pad which protected the workpiece from the pin of the compass, and the ink dot allowed that to be placed correctly.
Just being careful and stopping turning the cutter when the blade reached the yellow template was good enough to make the arc cuts, and a straightedge and knife made the cuts along the side of the centre bar and tidied up the messy bits.
Step 3: Cut Out Radiation Shape
This is an awkward little so-and-so. Having practiced the "circular cut with interruptions" on the prohibition layer, I cut the three arcs of the outside edge of the fan, then the three very short inside arcs.
A knife and straightedge joined the truncated slices fine.
The central disc was too small for the compass cutter, but I had a single hole punch which was perfect. I had to remove the chad catcher to fit the tool into the space available, but it worked well.
Inspired by that, I put rounded corners on the outside of the triangle and again used a knife and straightedge to join them up. Since the yellow is an intermediate layer, I peeled the pattern off the back of the sheet to avoid adding thickness.
Step 4: Mount Shapes
The pieces were laid up and fastened with double-sided tape.
It took a bit of thought to get the "prohibition" circle in place, so please experiment until you are happy before applying the tape.
Step 5: Final Layout and Cut Inserts
I laid the various pieces on the frame and tried different arrangements until I was happy with the look.
Then I marked around all the items to show where the recesses should be.
I cut pieces of scrap ply and chipboard to the right size to fit the frame, and then transferred the markings for placement onto the thin ply.As you can see, these two pieces stacked up were high enough to allow the gadolinium tube to fit.
Once the recesses were marked on the thin ply, the holes for all (except the deep recess for the gadolinium) were cut out. I used a 10mm (3/8") drill to put a starter hole and then used a jigsaw to cut round.
Once the three recesses were cut, the ply was glued and clamped to the chipboard and the glue was left to cure.
When the glue was cured, the deep recess was cut using the same method and then a thin piece of scrap ply was glued and clamped across the back.
Finally, a piece of acrylic was cut to fit the frame.
Step 6: Mounting Paper Items
I laid the paper items onto different colours of sticky-backed felt to choose which one looked better. I went with the black.
Cut a sheet of felt which is slightly larger than the front of the piece, remove the backing and apply.
Force the felt down into the shallow recesses with fingers. You can use clamps and male formers if its proving recalcitrant.
Once that's stuck, trim the excess from the edges (and keep the cut offs).
To upholster the deep recess which will hold the gadolinium tube, make an H-shaped cut with a knife in the felt above the deep recess. Fold the flaps down, and then use scraps of felt to cover the base and sides of the deep recess.
When all the recesses are carpeted with felt, clean all the dust and bits off the felt by wrapping some sellotape (other brands are available) around your fingers (sticky side out) and dabbing.
To give some strength to the paper material, I cut some scraps of acrylic to fit and used double-sided tape to hold the paper to them. I also trimmed tiny triangles off the corners just because it looked better.
Step 7: Scoring Break Lines
The "glass" in the front of the frame is to be scored so that it looks as if it is ready to break. To keep a smooth front, we made these score lines on the back of the acrylic.
Lay the acrylic over the piece and then mark the location of the gadolinium tube with some masking tape.
Turn the acrylic over, placing it on something soft which will not mark it.
Using a metal rule, drag a chisel point or knife point to mark a rectangle around the required area, and then make two diagonal scores across the rectangle.
Step 8: Mounting Hardware
The original frame back was held in place by angled nails. This back is too thick for that, so i had to use brackets. I found some Meccano (Erector) pieces which were perfect.
The chipboard of the thick piece at the back, and the customwood of the frame are both very soft, so a bradawl was enough to create the pilot holes. Then the brackets were secured with 3/4" screws (into the chipboard) and 1/2" screws (into the thinner frame).
Two screw eyes were put into the backing, and then a loop of wire was run through them and twisted shut.
Step 9: Completion and Lessons
The end result looked good. The use of coloured paper rather a printout gives a real intensity to the colours. Most importantly, I no longer have a tube of gadolinium on my desk waiting to be broken by accident.
Problems encountered were mainly caused by pushing on without complete planning.
The printed text was quite grey and no neighbour was able to provide darker print. Eventually I went to a copy shop where the file was printed out on 250gsm paper in a very dark black for fifty cents.
The method for fixing the completed object into the frame was unknown until the very end. Alternative ways might have been simpler in execution and not required pillaging my toybox.
The use of acrylic blocks behind the paper elements was unplanned, but worked well and will provide long-term support and prevent sagging.