BURNOUT AND POURING

Note:

<ab>When reheating, you might as well use common lute, But when you want to cast, strip it from the mold and, using a brush, quickly apply a layer of plaster lute that has been used for molds, because it will be dry as soon as it settles, and cast. This lute should be mainly placed on the joints.</ab>

[This means for two piece molds, when the molds are warm before casting, paint around where the two halves join with pure plaster.]

BURNOUT

Carefully vacuum out kiln, using the soft brush attachment.

The molds are still pretty wet, so we'll take the temp up slowly. It seemed to work best to take the molds up slowly, by 50-75 C every hour to 400 C.

In the beginning, we held the molds at the top temp for many hours, but Jef seems to have gotten good results with only 2 hrs or less at the highest temp.

Replace the wax trays at about 130C

POUR PLAN

Cool (or reheat) kiln to 120 C, take the molds out, blow out the ashes, then pour as fast as possible.

Melting point of tin: 449.5°F 231.9°C

Melting point of lead: 621.5F 327.5C

Kiln notes:

Kiln

Circuit breaker on, then switch in kiln
When on, hang signs on both door
When on, must be present on floor
When on, 12 in from wall
When on, NO open doors or windows
Wind tunnel, messes with hood
Log book ‐ record keeping only, not scratchwork for firing times
Running:
- Only me and postdocs and PS ‐ not students
- “2.30” = 2 hours 30 min
- Don't open at certain temp ranges
Hood doesn't pull as much smoke as it should
If lots of smoke, shut down and call EHS (switches
Can open more with a switch on top of hood ‐ but not proper
Careful of cracking inside or damage to door
Kiln wash --> manual
Always keep record, talk to student about what they want
For first/second run, ask PS to supervise

BURNOUT PLAN

Combination of pg 6 and 8 in kiln log

People	Start time	End time	Program	Rate (°C/hr)	Target temp (°C)	Duration	Notes
NJR	10pm	11pm	R1	50/hr	80	1 hr	We pre-programmed the kiln around 3pm. A 10 hour delay (an overshoot) was added so that we could start the kiln whenever we were ready
	11pm	1am	H1	--	80	2 hr
	1am	2am	R2	70/hr	150	1 hr	Around 120 or 30 min, replace wax trays (because it will make terrible smoke) If wax is not melted, play it by ear until it does melt out
THU	2am	3am	H2	--	150	1 hr
	3am	5am	R3	75/hr	300	2 hr
	5am	6am	H3	--	300	1 hr
	6am	8am	R4	50/hr	400	2 hr	Between 375 and 400, wax has consistently started to smoke out the door
NJR	8am	9am	H4	--	400	1 hr
	9am	12pm	R5	95/hr	110	3 hr	RAMPDOWN
	12pm	3pm	H5	--	110	3 hr
			Pour metal	~3pm

NOTES/OBSERVATIONS

Wed 9/27/17

Naomi

Preparation of molds before they went into the kiln

At the end of each mold, a shorthand key for easy identification was scratched in with a pencil. Measurements were also taken, summarized in the following table:

Mold Key and Dimensions
Key (shorthand)	Mold	Largest diameter (cm)	Height (cm)
B	Butterfly	14 ± 1	7 ± 1
S	Small single flower	9 ± 1	11 ± 1
M	Rosemary	9.5 ± 1	8.5 ± 1
T	Beetle	7.5 ± 1	4 ± 1
A	Asparagus	7.5 ± 1	16 ± 1
R	Rose	12 ± 1	12 ± 1
F	Flower bouquet	14 ± 1	14 ± 1
L	Leaf	20 ± 1	24 ± 1

Kiln measurements: height = 68cm, width (across door) = 60cm
LUTING
- Some of the molds required additional repair and/or luting
  - Asparagus
  - Flower Bouquet
  - Small single flower
  - Leaf
- Around 3-4pm, Pamela and Naomi mixed a batch of the mold material, tripling the base recipe and omitting eggs and iron oxide
  - 600ml plaster of paris (half of this was the brand new plaster (25lb bag) purchased in Sep 2017)
  - 300ml powdered brick (with quite a few lumps - doesn't matter too much for outside of the molds and preparation speed was a factor)
  - 600ml water
ASPARAGUS MOLD
- The stem of the asparagus was still poking out of the mold, and to prepare it for burnout, it was trimmed using a boxcutter until it was almost flush with the mold end
- We also noticed that the asparagus tip was poking out of the bottom end - it must have shifted during the plaster pour. The area around where it was poking out had about a quarter coin-sized eroded area with missing mold. This was repaired with luting
LEAF MOLD
- The edges where the two pieces of the mold meet were luted
- We also applied a clamp: two cast iron metal plates (8in x 6in) on either side tied together with armature wire. The wire was much stretchier than expected and getting a tight clamp was difficult

KILN RUN

9:30 pm Naomi arrives. All molds loaded into the kiln (gate-side down) onto wire racks

over metal pans to catch the wax

10:15 pm Hannah arrives. Kiln program started

Thurs 9/28/17

12:00 am Tillmann arrives. Hannah leaves.

1:30 am Kiln at 150 C. Tillman and Naomi opened the kiln to remove trays and the melted

wax. We used palette knives to scrape as much as we could off. We could see red and yellow wax (probably mostly gates) as well as 1 metal pin probably from the bottom of the rosemary mold

1:40 am Kiln door opened again to return the trays

2:00 am Tianna arrives

2:15 am Kiln door opened to see if blue sprues were melting. Two or three drops visible

on tray, nothing substantial.

2:20 am Tillmann leaves

2:30 am Naomi leaves

(Tianna notes)

3:10 am Smell of wax in the lab. No smoke.

3:20 am Smell of wax stronger. Kiln at 240 C. Thin wafts of vapour rising out of top of kiln

door; drops of condensation at top right side (see photo)

3:35 am Smell of caramelizing / early burning. Kiln at 270 C. Temperature drops to 265

over next few minutes. A strange little ramping program…!

4:17 am Smell of light smoke, but no smoke visible. Kiln at 306 C.

5:32 am Just checking on the kiln, which is now 331 C. It says it's in R4, which (I thought)

wasn't slated to start until 6 am. Something seems off in the timing.

7:05 am Naomi arrives.

7:40 am Sophie arrives. Tianna leaves.

(Naomi notes)

9:01 am 319.79 C

9:30 am 290 C

10:00 am 265 C

10:10 am FTC error? Ramp rate is too high for kiln to cool. Don't see a way to change rate

(only the target temp). Re-entered the same target of 110 C and Enter. Seems to be happy again

11:22 am 213 C

11:38 am 204 C

12:11 pm 188 C

12:40 pm 175 C

1:10 pm 160 C

1:45 pm 148 C. Pamela arrives. She opens kiln door to check on molds.

~3:15 pm Kiln turned off

3:30 pm PHS opens kiln door. Temp at 114 C.

4:30 pm Now at 96 C. New program started on kiln: R1 50/hr to 112; H2 at 112 for 1 hr

METAL CASTING

2017/09/28 3:00 pm

Pamela (PHS), Naomi (NJR), Tianna (THU), Sophie (SJP), Tillmann (TT), Hannah (HE)

Based on PHS's previous experience of Ms Fr 640's recommended alloys for life-casting, we aimed for a tin-lead alloy of 8 parts tin to 1 part lead

BATCH 1: (~ 3:25 pm)

IDEAL (8:1) 199.1 g tin (measured from existing ingots in lab) : 24.89 g lead (required)

Lead prep. 25.5 g before just lead melt; = 25.3 g after melt

ACTUAL 199.1 g tin : 25.3 g lead

YIELD ~ 125 g

USE leaf mold (blown out and poured by HE)

BATCH 2: (~ 3:40 pm)

IDEAL (8:1) 245.1 g tin (measured from existing ingots in lab) : 30.64 g lead (required)

ACTUAL 245.1 g tin : 30.4 g lead

YIELD ~ 275 g

USE ~ 2/3 into beetle mold (blown out by SJP and poured by TT) = 183.2 g (beetle)

REMAINDER ~ 1/3 ~ 91.7 g

BATCH 3: (~ 4:00 pm)

IDEAL (8:1) 131.5 g tin (measured from existing ingots in lab) : 16.43 g lead (required)

ACTUAL 131.5 g tin : 16 g lead

YIELD ~ 147 g

ADD 1/3 left over from BATCH 2 ~ 91.7 g

FULL YIELD ~ 240 g

USE rose mold (blown out by PHS/NJR and poured by SJP). Not enough!

BATCH 4: (~ 4:20 pm)

IDEAL (8:1) 462 g tin (measured from existing ingots in lab) : 57.75 g lead (required)

ACTUAL 462 g tin : 54.7 g lead

YIELD ~ 517 g

USE rose mold (second pour by SJP)
small flower (blown out by PHS/NJR and poured by NJR)

REMAINDER 125.6 g

**Note 4:35 pm — Rose mold extremely hot; still too hot to touch

BATCH 5: (~ 4:50 pm)

IDEAL (8:1) start with 125.6 g from BATCH 4

ADD 75.4 g (nipped cast excess from beetle)

YIELD 201.0 g

ADD 5.5 g (more nipped cast excess from beetle)

YIELD 206.5 g

ADD 31.1 g (nipped cast excess from small flower)

YIELD 237.6 g

ADD 41.3 g (nipped cast excess small flower)

FULL YIELD 278.9 g

USE rosemary mold (blown out and poured by NJR).

Much left over

BATCH 6: (~ 5:10 pm)

We have no additional 8:1—tin:lead alloy
We have no additional pure tin, though we do have additional pure lead
We have some prepared 3:1—tin:lead alloy
We have yet to pour the butterfly and the asparagus, and we are concerned that we might not have enough left over from BATCH 5 to cover both
Decision: add chunks of 3:1—tin:lead alloy to our leftover 8:1—tin:lead alloy
We will need to measure the weight of the rosemary pour when it is un-molded and then deduce how much is leftover to be used for the butterfly
See “calculations section” below

In red are additions from calculations section

IDEAL start with leftovers from BATCH 5 = 234.2 g (8:1)

ADD (3:1) 138.0 g

ADD (3:1) 55.7 g

ADD (3:1) 24.6 g

ADD (3:1) 6.5 g

TOTAL (3:1) 224.8 g

YIELD (~4:1) 459.0 g

USE butterfly mold (blown out and poured by THU)

asparagus mold (blown out by THU and poured by TT) some left over

REMAINDER = (Full yield) - (butterfly) - (asparagus)

= 459.0 - 69.0 - 134.8 g

= 255.2 g (~4:1)

BATCH 7: (~ 5:40 pm)

IDEAL start with leftovers from BATCH 6 = 255.2 g (~4:1)

ADD (3:1) 181.9 g

YIELD (~4:1) 255.2 + 181.9 = 437.1 g

USE bouquet (blown out by THU and poured by PHS)

REMAINDER (~4:1) 437.1 g - WEIGHT OF BOUQUET

NEED TO MEASURE WEIGHTS OF

Rosemary (44.7 g — measured 2017/09/29)
Butterfly (69.0 g — measured 2017/09/29)
Asparagus: 134.8 g (including some small rocks from the coarse sand into which the metal leaked

CALCULATIONS FOR COMPOSITION OF METAL AFTER BATCH 5

BATCH 5 at 8:1 = 278.9 g
--> poured rosemary = 44.7 g
BATCH 5 REMAINDER = 278.9 - 44.7 g
- = 234.2 g (8:1)
BATCH 6
- Composed of
  - BATCH 5 REMAINDER (8:1) 234.2 g
    - To calculate how much tin and how much lead

Composition consists of 9 parts

1 part = 234.2/9 g = 26.022 g

Tin (8 parts) = 208.178 g
Lead (1 part) = 26.022 g

ADD (3:1) 224.8 g
- To calculate how much tin and how much lead

Composition consists of 4 parts

1 part = 224.8/4 = 56.2 g

Tin (3 parts) = 168.6 g
Lead (1 part) = 56.2 g

Final composition
- Tin = 208.178 + 168.6 g = 376.778 g
- Lead = 26.022 + 56.2 g = 82.222 g
- YIELD = 459.0 g
  - Composition
    - Tin = 82.09%
    - Lead = 17.91%
This is approximately 80:20 = (4:1)

BATCH 7
- Composed of
  - BATCH 6 REMAINDER (~4:1) 255.2 g
    - To calculate how much tin and how much lead (using approximation of 4:1)

Composition consists of 5 parts

1 part = 255.2/5 = 51.04 g

Tin (4 parts) = 204.16 g
Lead (1 part) = 51.04 g

ADD (3:1) 181.9 g
- To calculate how much tin and how much lead

Composition consists of 4 parts

1 part = 181.9/4 = 45.475 g

Tin (3 parts) = 136.425 g
Lead (1 part) = 45.475 g

Final composition
- Tin = 204.16 + 136.425 g = 340.585 g
- Lead = 51.04 + 45.475 g = 96.515 g
- YIELD = 437.1 g
  - Composition
    - Tin = 77.92%
    - Lead = 22.08%
This approximately 80:20 = (4:1)

SUMMARY OF COMPOSITION OF EACH ITEM

Composition of each item
Item	(Tin:Lead)
Butterfly	(~4:1)
Small single flower	(8:1)
Rosemary	(8:1)
Beetle	(8:1)
Asparagus	(~4:1)
Rose	(8:1)
Flower bouquet	(~4:1)
Leaf	(8:1)

NOTES/OBSERVATIONS ON CASTING/UNMOLDING

Can melt chunk of tin-lead alloy into already melted metal just by dipping in
Really good mold material that held up to heat yet was friable
- Leaf = good friability (unmolded PHS 1.5 hrs after pour)
- Beetle = good friability (unmolded PHS/SJP? 1.5 hrs after pour)
- Small flower = less good friability (ummolded PHS/NJR? 1.5 hrs after pour) (thick, quick-setting wet plaster)
- Butterfly = not very friable, taking firm pressure and multiple blows to break (unmolded THU 24 hrs later) (thick, quick-setting wet plaster)
- Bouquet = good friability (unmolded TT 24 hrs later)
- Rosemary = extremely friable, easy to take apart, falling apart in hands (unmolded NJR 24 hrs later)

PHS NOTES 10/28/17 for next time: