1. Pellet Dies: User Instructions Read these instructions carefully before beginning work. Read the risk assessment. If you have not used the die and hydraulic press before, consult a trained user before using the system alone.

2. Pellet Dies: Preparation Clean and inspect all the die components for damage before use. Check the hydraulic press and tidy the area around the press before starting work. Ensure that you have the correct PPE (e.g., safety glasses, gloves, lab. coat).

3. Pellet Dies: Preparation Before pressing your own sample follow the instructions given in this booklet and press a stearic acid pellet. Note, the user instructions for the 5 mm die differ slightly from the instructions for the 13 and 32 mm dies. Make sure that you read and understand the correct set of instructions. If you are unsure at any time STOP and ASK a trained user.

4. Sample Loading Assemble the die components as shown. Fit the base (A) onto the die body (B). Insert a die pellet (1) into the die bore with its shiny face up. Place your powder sample (2) into the bore of the die. Brush away any excess powder. Add enough material to make a pressed pellet of no more than 5 - 10 mm in height although a pellet can be much thinner if required. Insert the second metal die pellet (3) with shiny face down towards the sample as shown. (A) (B) (1) (2) (3) Instructions for 13 and 32 mm dies

5. Sample Pressing Insert the plunger (C) with the tapered end at the top. Place a rubber O-ring (D) over the plunger. You are now ready to press your sample! (A) (B) (1) (2) (3) (C) (D)

6. Sample Pressing Insert the assembly into the hydraulic press. Put on your safety glasses and close the hydraulic press door. SLOWLY force the plunger into body of die using ram. Do not exceed 10 tons on the plunger for 13 mm and 45 tons for 32 mm dies. In practice, this means just 2 tons of load on the ram for a 13 mm die. For the 32 mm die you can apply up to 40 tons on the ram but there is no need to go past 20 tons in most cases. Apply the load slowly to ensure that you do not exceed the maximum allowed force on the die. (A) (B) (1) (2) (3) (C) (D)

7. Load on die versus load on the ram The load on the die scales with the area of the die. The force on the ram is given by the outer scale on the hydraulic press. The middle scale gives the force on a 1¼ inch (32 mm) die. The inner scale gives the load on a ½ inch (13 mm) die. For the 5 mm die the outer scale should be divided by a factor of ~40 so a 2 ton load on the die is only ~0.05 ton load on the ram. Load on ram Load on 1¼ inch (32 mm) die Load on ½ inch (13 mm) die

8. Sample Removal Once your pellet is pressed, release the pressure on the ram. Remove the die base. Invert the assembly and place the set up between the rams of the hydraulic press. Position the perspex extraction ring (E) as shown. Check your safety glasses and close the press door. (B) (1) (2) (3) (C) (E)

9. Sample Removal SLOWLY force the plunger further into the body of die. The die pellet (1), then the pressed sample (2), and finally the second die pellet (3) should emerge from the body of the die. This extraction should require LITTLE or NO force on the ram. If at any time you notice that the load on the ram is non-zero STOP and seek help. (B) (1) (2) (3) (C)

10. Tidying up! Carefully remove your pressed pellet (2) and the lower die pellet (3). You should be able to pull the plunger back out of the die body with your fingers. Clean everything and then press another stearic acid pellet. Clean everything again, tidy up the area around the hydraulic press and replace all the parts of the die into the storage box. (B) (2) (3) (C)

11. Sample Loading Invert the empty die body (A) and insert the plunger (B) with the die body resting on the tufnol ring (C). Insert a die pellet (1) with the shiny face up as shown. Place your powder sample (2) into the bore of the die. Add enough material to make pellet of no more than 3 mm in height although a pellet can be much thinner if required. Insert a second metal die pellet (3) with its shiny face down towards the sample as shown. (2) (1) (3) (B) (A) (C) Instructions for 5 mm die

12. Sample Loading Fix the die base (D) over the body of the die as shown. With your finger on the plunger to ensure everything stays in place, invert the whole assembly. (D)

13. Sample Loading Remove the tufnol ring. Place a rubber O-ring (E) over the plunger. You are now ready to press your pellet! (E)

14. Sample Pressing Insert the assembly into the hydraulic press. Put on your safety glasses and close the press door. SLOWLY force the plunger into body of die using ram. Do not exceed 2 tons on the 5 mm plunger. Note, this means a little less than 0.05 ton load on the ram. Apply the load slowly to ensure that you do not exceed the maximum allowed force on the die.

15. Sample Extraction Once you have pressed your sample release the pressure on the ram. Remove the die base. Invert the assembly of the die, making sure the plunger does not fall out. Position the perspex extraction ring (F) as shown. (F)

16. Sample Extraction Place the whole assembly inside the press and slowly move the ram down until it touches the perspex ring, holding the entire assembly in place. Close the press door.

17. Sample Extraction Slowly lower the ram as shown The die pellet, then the pressed sample, and finally the second die pellet should emerge from the body of the die BEFORE the plunger reaches the tapered section of the die body. This extraction should require LITTLE or NO force on the ram. If at any time you notice that the load on the ram is non-zero STOP and seek help.

18. Plunger Extraction Once the pellet has been extracted try to pull the plunger back out of the die body. If it is stuck you can get it moving using the vice on the mezzanine in Room P122. Place the tufnol ring over the end of the die with the wider bore, so that the plunger is free to move through the hole. Insert a short piece of soft material (G) that will not damage either the plunger or the die body, e.g. a short section of a wooden paintbrush handle into the narrow end of the die bore. Clamp the assembly in the vice as shown and slowly close the vice jaws (H) to ease the plunger back out of the die. Once the plunger has moved even a few mm, you should be able to pull it out by hand. (H) (G)

19. Tidying up! Clean everything and then press another stearic acid pellet. Clean everything again, tidy up the area around the hydraulic press and replace all the parts of the die into the storage box.