Static Tests
 
Performed on the electronic test stands

January through December 2006

< Go to 2005 Tests

Go to 2007 Tests >
Excel File
Thrust Curve
Description
Video
1-1-06A

18mm paper case motor, 4 inch length, burning 2.75 inch moonburner grain.  Primed by inserting a strand of black match in the grain core, extending its full length and overlapping the ends by 1/4 inch or so.  Grain is inhibited with one wrap of Nashua 322 Al-foil tape.  Ignited with new ignitor, Christmas-tree bulb which has it's tip ground off in a belt sander, filled with finely-ground meal powder, and sealed with a tad of fuse paper.  Held in motor nozzle with masking tape and fired with Estes 4-AA launch controller.  
Propellant weight:  13.2ag  Total thrust:  12.3Ns,  Burn time:  0.8 seconds,
ISP:  95 (a bit optimistic, as the the delay grain would have contributed a little, inflating the score.  More conservative:  Propellant weight is 14.9g, ISP is 84.)
Video
1 meg,
7 seconds

.wmv file

1-1-06B
Analysis
(Excel file) 
 
18mm paper case motor, 6 inch length, burning 4.2 inch moonburner grain.  Primed by inserting a strand of black match in the grain core.  Ignited with new ignitor, Christmas-tree bulb which has it's tip ground off in a belt sander, filled with finely-ground meal powder, and sealed with a tad of fuse paper.  Held in motor nozzle with masking tape and fired with Estes 4-AA launch controller.  
Propellant weight:  19.8g (not including delay grain)  Total thrust:  18.75Ns,
Burn time:
 0.58 seconds, ISP:  96  - probably not... some of the delay grain burned as propellant, inflating the score.  If one web thickness of propellant (1.7g) is assumed to have burned during the propellant phase, then the total propellant producing thrust would have been 21.5g and the ISP 89.
Video
1 meg,
9 seconds, .wmv file



1-8-06B
Analysis
(Excel file) 
 spreadsheet

38-360 Dr. Rocket motor casing firing single uninhibited grain of KN/SB/SU propellant made on 12/25/05.  Made in the electric skillet, proprotions are 66/17.5/17.5.  A small amount of corn syrup was added to improve its working texture.  

In an effort to facilitate quick ignition, the bare grain is wrapped in fuse paper made from coffee-filter paper, and a strand of this paper is run along the section of ignitor wire inside the core.  It seemed to work, as ignition lag was about .5 second, and the motor rose to pressure much more quickly than on the previous attempt.

Propellant weight:  130.1g  
Total thrust:
 148Ns  
Burn time:
 0.38 seconds,
Delivered ISP:  116

Thus KN/SB/SU appears to be a viable propellant.  Whether it offers significant advantages over KN/SB or KN/SU is yet to be determined.
Video
850k
.wmv file
4 seconds
1-14-06A
Analysis
(Excel file) 

38-240 casing, uninhibited grain using KNO3, sorbitol, sucrose, and dextrose in the percentages:  KN= 66  SB=22  SU= 8.8  DX=2.7 
The propellant was made in the electric skillet, and cooked quite a lot at 250 degrees over the course of several days.  It is rather hygroscopic, and a bit soft even the next day, but produced a good grain.

Propellant weight:  103.1g  
Total thrust:
 113Ns  
Burn time:
 0.70 seconds,
Delivered ISP:  112

Good burn, nice curve.  slower than would be expected for KN/SU, but Kn ratios were a bit low (188max, 155final) which could have reduced both burn rate and ISP.
Video
750k
.wmv file
4 seconds

1-15-06B
Analysis
(Excel file) 
38-240 casing, uninhibited grain using skillet rcandy made by a quicker method than usual.  Once the evaporating mixture reached the "crystal mush" stage, it was stirred every 2 to 3 minutes until a cooled sample became firm.  This only took about 10 minutes, whole process to make 300 gram batch took 35 minutes.  

Propellant weight:  107.7g  
Total thrust:
 117Ns  
Burn time:
 0.56 seconds,
Delivered ISP:  116

Except for the propellant, this test is very similar to 1-14-06A, and was done primarily to compare the two propellants.  They are different.
Video
900k
.wmv file
4 seconds
1-16-06A
Analysis
(Excel file) 
38-240 casing, uninhibited grain using the same skillet rcandy as the previous test 1-15-05B.  Motor and test are the same except steel washer with .331 inch hole is used as nozzle throat.  This in an effort to develop a standard test motor, with a stable and reporducible nozzle throat size which will be necessary for comparing propellant variations.  Also ignitor is bridge wire with fuse paper, no BP.

Propellant weight:  109.4g  
Total thrust:
 129Ns  
Burn time:
 0.48 seconds,
Delivered ISP:  120

Very quick igniton, good burn.  Higher ISP could be attributed to higher Kn ratios.
Video
824k
.wmv file
4 seconds
1-21-06B
Analysis
(Excel file) 
38-240 casing, uninhibited grain composed of skillet rcandy made with KNO3 from SVRC (pvconly.com)  This KNO3 is a little different from the food grade stuff I've been using, and tends to make a dry propellant.  Water added at intervals to keep it's creamy texture. Mistake - smaller nozzle throat used than intended, generating higher pressure, higher thrust, and truncated thrust curve.  Ignitor is bridge wire with fuse paper, no BP.

Propellant weight:  104g  
Total thrust:
 122Ns  
Burn time:
 0.30 seconds,
Delivered ISP:  119

Very quick igniton. Fast burn attributed to higher Kn ratios.
Video
839k
.wmv file
4 seconds
1-21-06C
Analysis
(Excel file) 
38-240 casing, Same propellant load as 1-21-06B except gain on load cell amp set lower in order to capture full data.  

Propellant weight:  104.9g  
Total thrust:
 122Ns  
Burn time:
 0.35 seconds,
Delivered ISP:  119

Very quick igniton. Fast burn and higher ISP could be attributed to higher Kn ratios.
Video
832k
.wmv file
4 seconds
1-22-06C
Analysis
(Excel file) 
38-240 casing, Uninhibited grain made from oven-rcandy using KNO3 from SVRC (pvconly.com) burning at 5.4 seconds per inch at 1 atm.  Similar to tests on 1/21 except for oven-made propellant and the nozzle throat, this time 0.327 inch diameter.

Propellant weight:  109.8g  
Total thrust:
 133Ns  
Burn time:
 0.48 seconds,
Delivered ISP:  124

Quick ignition - In this and the last few tests, the grain is wrapped in fuse paper, with a little overlap at either end.  Ignitor is bridge wire wrapped with fuse paper to diameter of about 1/4 inch, and 2 strips of fuse paper packed into grain core behind the ignitor, sealing it in.  This flammable plug is thought to divert ignition gasses toward the head end and around the outside of the grain, where fuse paper helps spread the flame.
Video
839k
.wmv file
4 seconds
1-29-06A
Analysis
(Excel file) 
38-240 casing, Uninhibited grain made from skillet-rcandy using KNO3 from SVRC (pvconly.com) burning at 5.4 seconds per inch at 1 atm.  First test of new steel nozzle made by Jon Carter.

Propellant weight:  100.2g  
Total thrust:
 128Ns  
Kn ratios:  Initial, 273     Final, 219
Burn time:  0.38 seconds,
Delivered ISP:  130

New nozzle performed well, may have contributed to better-than-average ISP.  It is discolored a bit, but still smooth.
Video
902k
.wmv file
4 seconds
1-29-06C
Analysis
(Excel file) 
38-240 casing, Uninhibited grain made from open-pan rcandy using KNO3 from Skylighter burning 9 seconds per inch at 1 atm.  Second test of new steel nozzle made by Jon Carter.

Propellant weight:  106.6g  
Kn ratios:  Initial, 273     Final, 219
Total thrust:  138Ns  
Burn time:
 0.44 seconds,
Delivered ISP:  132

New nozzle performed well.  Again, ISP is better than I usually see in these motors.
Video
847k
.wmv file
4 seconds
1-29-06D
Analysis
(Excel file) 
38-240 casing, Uninhibited grain made from open-pan rcandy using KNO3 from Skylighter burning 9 seconds per inch at 1 atm.  Third test of new steel nozzle made by Jon Carter.  Grain adjusted to exactly 100g to provide close test to 1-29-06A, but this grain is shorter, indicating that the propellant made with SVRC KNO3 is a bit less dense.  
Propellant weight:  100.0g  
Kn ratios:  Initial, 256     Final, 203
Total thrust:  126Ns  
Burn time:
 0.46 seconds,
Delivered ISP:  128

New nozzle performed well.  ISP is a tad lower, perhaps because smaller grain offers lower Kn ratios.
Video
903k
.wmv file
4 seconds
1-29-06E
Analysis
(Excel file) 
38-240 casing, Uninhibited grain made from open-pan rcandy using KNO3 from Skylighter burning 9 seconds per inch at 1 atm.  Added 0.9g Fe2O3 to this propellant.  

Propellant weight:  103.9g  
Kn ratios:  Initial, 263     Final, 209
Total thrust:  137Ns  
Burn time:
 0.33 seconds,
Delivered ISP:  135

Fourth test of new steel nozzle made by Jon Carter.  After a rinse and a wipe, it still looks good.  No measurable erosion.  Faster burn is attributed to Fe2O3, probably higher ISP too because of higher pressure.
Video
903k
.wmv file
4 seconds
2-26-06A
1 through 4

Endburners - 3/4ths inch ID paper tubes used to make end-burning motors, in an effort to determine whether rcandy might serve as a propellant in Jetex-type motors.

Thrust was higher than expected, so these motors might see use as long-burning sustainers.

See the Endburner page for details and videos.

3-5-06A
(click for Excel spreadsheet analyzing this test)


54mm Loki 1600 casing, burning 4 BATES grains skillet rcandy.  This is my first test of this motor.  Nozzle is old-style, throat drilled to 0.5 inch diameter.  New nozzle has inset shoulder for support ring, allowing 0.3 inch more propellant column and requiring slightly longer case liner.

Propellant weight:
 723g  
Kn ratios:  Initial, 212     Max, 246    Final, 220
Total thrust:  829Ns  
Burn time:
 1.44 seconds,
Delivered ISP:  116

Ignition was with fuse paper alone in ignitor.  Fuse paper also placed between grains and wadded in core to speed ignition.  Ignition lag of 1.3 seconds is acceptable, but could be better.

Case is undamaged and cleaned up well.  Successful test!
Video
941k
.wmv file
6 seconds

3-25-06
Excel spreadsheet analyzing this test
18mm motor using Pixy Stix rcandy.  Substituted the contents of a dozen Pixy Stix for an equivalent amount of sugar, prepared by the electric skillet method.  Propellant catalyzed with 1% Fe2O3.

Propellant weight:  7.4g  
Kn ratios:  Initial and max, 130    Final, 108 in theory, actually more likely 60 due to nozzle erosion
Total thrust:  5.84Ns  
Burn time:
 0.27 second,
Delivered ISP:  81

Test demonstrates that this kind of candy can be used to make a viable propellant.  It does not seem much different from propellant made with pure sucrose.  
Video
1 meg .wmv file
8 seconds duration 
4-1-06B
Analysis
(Excel file) 
38-240 motor using Pixy Stix rcandy.  Substituted contents of two 4-ounce packages Pixy Stix for an equivalent amount of sugar, prepared by the electric skillet method.  Burn rate at 1atm is 18 seconds per linear inch

Propellant weight:  106.3g  
Kn ratios:  Initial and max, 284    Final, 228 
Total thrust:  133Ns  
Burn time:
 0.48 second,
Delivered ISP:  128

Comparison of this test with those performed on 1/29/06 shows that rcandy made with Pixy Stix performs much like that made with pure sucrose.  Seems like Pixy Stix is just a bad way to buy sugar.
Video
1.5 meg .wmv file
10 seconds duration 
4-6-06D Jon Carter's 54mm casing burning 3 BATES grains skillet rcandy.  This is the first test of this motor.  Nozzle is old-style Loki, throat is 0.435 inch diameter.  

New  2.3 inch long smoke grain made with rcandy/RIO burning 7 seconds per inch.  

Propellant weight:
 536g  
Kn ratios:  Initial, 206     Max, 242    Final, 221
Total thrust:  676Ns  
Burn time:
 1.35 seconds,
Delivered ISP:  129

Ignition was with Jon's ignitor.  Bridge wire dipped in bp/nc laquer pyrogen and inserted inside a molded black powder grain about 3/8ths inch dia.  It can be seen exiting the motor during ignition phase.
Video
3 meg .wmv file
29 seconds duration 
4-7-06A


Jon Carter's 38mm casing burning 2 BATES grains KN/SB propellant with 5% iron made on 5/21/05. No apparent rust even after nearly a year in storage  

Delay grain 65%KNO3, 8%RIO, 27%Mr. Fiberglass epoxy.  Grain length is .75 inch, drilled with 5/16this bit to .548 inch depth.

Propellant weight:
 112g  
Kn ratios:  Initial, 139     Max, 175    Final, 166
Total thrust:  93Ns  
Burn time:
 1.12 seconds,
Delivered ISP:  95

Ignition was slow, but good buildup to pressure once things got going.  Ejection charge fired 6.7 seconds after onset of thrust.
Video
5 meg .mpg file
15 seconds duration 

4-16-06B

38-240 motor using KN/Dextrose rcandy.  Mixed 100g KNO3, 60g dextrose, and 100 ml water, prepared by the electric skillet method.  Burn rate at 1atm is 15 seconds per linear inch

Propellant weight:  103.3g  
Kn ratios:  Initial and max, 276    Final, 222
Total thrust:  128Ns  
Burn time:
 0.53 second,
Delivered ISP:  124

This test to demonstrate that KN/Dextrose can be made by the rcandy method.  Apparently so, as it produced a very good propellant in this trial.  No Karo was needed to achieve good working texture.
Video
5 meg .mpg file
15 seconds duration 

4-16-06E 38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) acidified with 2% boric acid.  Propellant turned a dark peanut butter color and would not support its own combustion at 1 atm.  But it burned well under pressure.  And it has a nice working texture.  

Propellant weight:  96.6g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  111Ns  
Burn time:
 0.55 second,
Delivered ISP:  118

Tall peak at beginning of burn thought due to large ignitor covered with lotsa masking tape.  Seems likely that it plugged the nozzle temporarily, creating higher pressure than expected.
Video
1 meg .wmv file
5 seconds duration 
4-17-06B 38-240 test of KNO3/Sorbitol skillet rcandy.  Batch 4/16/06C.  Tested strand on 4/16, burns very fast.  Tested again on 4/17, burns at 10 seconds per linear inch.

Propellant weight:  97.2g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  102Ns  
Burn time:
 0.78 second,
Delivered ISP:  107

Grain mashed a bit flat on one end, may be responsible for long taper-off in video.  Good burn.

Video
1 meg .wmv file
5 seconds duration 
4-17-06C 38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) acidified with 2% boric acid.  Peanut butter color, despite my stirring it every minute or so.  Non-continuous burn at 1 atm.  But it still has a very nice working texture.  

Propellant weight:  95.5g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  108Ns  
Burn time:
 0.58 second,
Delivered ISP:  115

Except for a few jitters, thought to be test stand artifacts, this one provides a classic uninhibited-grain profile.
Video
1 meg .wmv file
5 seconds duration
4-17-06D 38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) acidified with 2% boric acid.  Same batch as 4/17/06C

Propellant weight:  96.2g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  112Ns  
Burn time:
 0.64 second,
Delivered ISP:  119

Tall peak at beginning of burn thought due to tight wad of fuse paper stuffed in core of propellant grain to facilitate ignition.  Apparently, it worked.
Video
1 meg .wmv file
5 seconds duration
4-19-06B
(Click for Excel Spreadsheet)

38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) acidified with vinegar which added 1.6% acetic acid.  This propellant remained light in color during the entire cooking process, and burns at a high rate at 1 atmosphere - 6.5 seconds per linear inch.  Texture is very nice, easy to handle, easy to mold, and makes a sturdy grain.

Propellant weight:  97.6g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  120Ns  
Burn time:
 0.42 second,
Delivered ISP:  125

ISP higher than 4/17 tests, thought due to faster burning propellant.  Jitters on thrust curve may be test stand artifact, or maybe not, as some variation in the exhaust flame can be seen in the video.  
Video
1 meg .wmv file
5 seconds duration
4-19-06C 38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) acidified with vinegar which added 1.6% acetic acid.  Same propellant batch as used in 4-19-06B.

Propellant weight:  93.7g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  112Ns  
Burn time:
 0.39 second,
Delivered ISP:  122

Another good test.  This propellant burns well, if a bit fast.  Texture is outstanding, leading me to wonder if the acid and heat are inverting the sugar?
Video
1 meg .wmv file
5 seconds duration
4-23-06A 38-240 test of skillet rcandy using KNO3 from SVRC (pvconly.com) and Pixy Stix for sugar and acid.  Texture and burn rate are good.

Propellant weight:  94.2g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  105Ns  
Burn time:
 0.48 second,
Delivered ISP:  114

Sucrose & citric acid had worked well before.  This test is to determine if Pixy Stix has enough citric acid to neutralize this KNO3.  Apparently it does.
Tested on 500lbf test stand.
Video
1 meg .wmv file
5 seconds duration
4-23-06B 38-240 test of skillet rcandy using Champion Bulldog fertilizer-grade KNO3 and vinegar to acidify the mix.  Texture is excellent, burn rate of 19 seconds per linear inch is good in a motor.

Propellant weight:  97.2g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  105Ns  
Burn time:
 0.53 second,
Delivered ISP:  110

Test to determine if acidifying this blue fertilizer KNO3 will make it work better.  It's OK, but might have worked with the skillet method and no acid.  I'll try that one day.
Tested on 500lbf test stand.
Video
1 meg .wmv file
5 seconds duration
4-23-06D 38-240 test of skillet rcandy using Champion Bulldog fertilizer-grade KNO3 and vinegar to acidify the mix.  This batch is very dark, a milk-chocolate color.  Texture is very good, but it does not burn continuously at 1 atmosphere.  

Propellant weight:  92.2g  
Kn ratios:  Initial and max, 272    Final, 218
Total thrust:  92Ns  
Burn time:
 0.61 second,
Delivered ISP:  102

Tested on bath scale test stand.  I'm not sure it is reading accurately.  Low ISP could thus be a test stand artifact, the result of lower pressure, or something else.  
Video
1 meg .wmv file
5 seconds duration
4-28-06A 54mm Loki motor shortened from 3-grain length to 2 grains.  First test of this motor after its CATO at the February launch.  Jon Carter trimmed it off and cut a new groove, and also anodized it again.  Very pretty!  This test is primarily to prove the modified case, and it did quite well.


Video
5 meg .wmv file
15 seconds duration
5-6-06D Loki 2000 casing, 54mm 5-grain.  First test.  Burning propellant made with SVRC KNO3, Pixy Stix, Karo Syrup and vinegar.  4 BATES grains and full-sized smoke grain.  But smoke grain burned simultaneously with propellant, yielding high thrust but no after-smoke.

Propellant weight:  859g  
Kn ratios:  Initial 273,  Max, 326    Final, 301
Total thrust:  1105Ns  
Burn time:
 0.93 second,
Delivered ISP:  131

High thrust is at penalty of extreme pressure (around 1800 psi) and short burn time.  Case liner is split from one end to the other.  No apparent damage to motor casing.

Video
2 meg .wmv file
7 seconds duration
Spreadsheets:


5-21-06D1
No aluminum


5-21-06D2
+ 5% aluminum
Aluminum Rcandy Tests  

Two static tests of similar grains fired in the 38-240 casing using same nozzle throat size.  One (D1) is plain rcandy with 0.5% citric acid and 0.5% red iron oxide added.  The second (D2) is the same batch of propellant, but with 5% fine aluminum dust added.  The aluminum is 2 micron Indian Blackhead aluminum, about a year old.  

The question has been posed as to whether aluminum is ignited by burning sugar propellant, and if so, what effect it might have on thrust, pressure, and other significant factors.  

I suspect the slow build-up to pressure of motor D2 is the primary cause of its relatively low ISP.  But since the grain was not weighed (duh!) it could have been slightly lower in mass.  Made in same mold as D1 grain, it should have had pretty much the same dimensions.

Alternatively, adding fuel without adding more KNO3 would have made for a fuel-rich propellant, also possibly altering potential ISP.

5/21/06D1

Propellant mass:  98.7g  
Kn ratios:  Initial and max, 270    Final, 219
Total thrust:  107Ns  
Burn time:
 0.42 second,
Delivered ISP:  111


5/21/06D2

Propellant mass:  XX.Xg  
Kn ratios:  Initial and max, 270    Final, 219
Total thrust:  98Ns  
Burn time:
 0.38 second,
Delivered ISP:  101


Photos taken at approximate peak thrust for each motor.

Residue from D2 firing dropped in vial containing sodium hydroxide solution.  There was a fair amount of bubbling, suggesting the presence of unburned aluminum.
D1 Video

D2 Video

Each video is 1 meg .wmv file, 5 seconds



Strand Burn Video

2 meg .wmv file, 10 seconds of exciting video!
5-22-06A Aluminum Rcandy test - replication of 5/21/06D2 but this time I remembered to weigh the grain!  Same batch of propellant used, re-heated and grain molded in same mold.

Propellant mass:  98.9g  
Kn ratios:  Initial and max, 270    Final, 219
Total thrust:  114Ns  
Burn time:
 0.41 second,
Delivered ISP:  117

ISP is in the ballpark with previous tests using this motor, suggesting that test 5/21/06D2 was a fluke, and Al-candy propellant can offer at least normal performance.  With corrected O/F ratio, it might even be an improvement.
Video
1  meg .wmv file, 5 seconds
7-1-06A 29mm Loki 2-grain motor, fired with one long grain.  Propellant is made from a mixture of hard candies and food-grade KNO3.  Ignitor is fuse paper with bridge wire.

Propellant mass:  45.5g  
Kn ratios:  Initial, 129    Final and max, 222
Grain:  Len 3.125,  OD 0.9, Core .3125
Nozzle throat:  0.203 inches
Total thrust:  56Ns  
Burn time:
 0.74 second,
Delivered ISP:  126

Quick ignition, good thrust.  Curve is expected to be progressive, and it is.  
I'll try it with BATES grains next time.


Video
1  meg .wmv file, 5 seconds
7-2-06D 29mm Loki 2-grain motor, fired with two BATES grains.  Propellant is made from a mixture of hard candies and food-grade KNO3, cooked until not continuous at 1 atm, added 1% yellow iron oxide makes it burn 8 seconds/inch.  Ignitor is fuse paper with bridge wire.

Propellant mass:  45.5g  
Kn ratios:  Initial 166, Max 197, Final 177
Grain:  Len 1.6in,  OD 0.9, Core .325
Nozzle throat:  0.203 inches
Total thrust:  45Ns  
Burn time:
 0.4 second,
Delivered ISP:  107

Quick ignition, good thrust.  Curve is a little peakier than I expected, possibly due to the YIO.
Video
1  meg .wmv file, 5 seconds
10-29-06B1
Spreadsheet
10-29-06B118mm Model rocket motor using 3 small BATES grains.  1/4th inch nozzle made with 1/2 tsp Bentonite, rammed in a single increment.  This proves strong enough.  
Kn ratios     Initial:  40
                   Max:   44
                   Final:   27

Hey!  I was wondering why the thurst curve was so regressive.  Now I know.  The grains are shorter than the ideal BATES length, and their Kn progression indicates a regressive burn.

Peak Thrust: 5.4979 Lbs-force 
Average Thrust: 3.7740 Lbs-force 
Burn time: 0.43 Seconds 
Total Thrust: 1.64 Lb-Seconds
Total Thrust: 7.27 N-Seconds
Propellant weight: 0.0089 Kg 
Propellant weight: 0.020 pounds
ISP, Delivered 83.31 Seconds
Video
1  meg .wmv file, 4 seconds
10-29-06B2
Spreadsheet
10-29-06B218mm Model Rocket motor burning a single long grain.  Otherwise just like 10-29-06B1.  
Kn ratios
Initial:  26
Final:   49


Peak Thrust: 5.0452 Lbs-force 
Average Thrust: 3.8771 Lbs-force (1)
Burn time: 0.41 Seconds (1)
Total Thrust: 1.62 Lb-Seconds
Total Thrust: 7.19 N-Seconds
Propellant weight: 0.0089 Kg 
Propellant weight: 0.020 pounds
ISP, Delivered 82.38 Seconds

Video
1  meg .wmv file, 5 seconds
10-29-06B3
Spreadsheet
10-29-06B318mm Model Rocket motor, Single uninhibited grain.  Otherwise just like B1 and B2 above.  This is a real test of the short nozzle stack, 1 tsp Bentonite clay rammed in a single increment.  
Kn ratios   Initial:  40
                 Max:   44
                 Final:   27


Peak Thrust: 12.5482 Lbs-force 
Average Thrust: 7.6729 Lbs-force (1)
Burn time: 0.23 Seconds (1)
Total Thrust: 1.79 Lb-Seconds
Total Thrust: 7.96 N-Seconds
Propellant weight: 0.0089 Kg 
Propellant weight: 0.020 pounds
ISP, Delivered 91.30 Seconds
Video
1  meg .wmv file, 5 seconds
12-2-06B38-240 casing burning propellant made with Lyle's Golden Syrup and no other sugar.  

Kn initial and max:  272                 Kn final:  188

Peak Thrust: 37.9882 Lbs-force 
Average Thrust: 31.2401 Lbs-force (1)
Burn time: 0.84 Seconds (1)
Total Thrust: 26.42 Lb-Seconds
Total Thrust: 117.53 N-Seconds
Propellant weight: 0.1050 Kg 
Propellant weight: 0.232 pounds
ISP, Delivered 114.22 Seconds

Burn is strong, ISP in the ballpark.  Flame flickers noticeably, but thrust curve follows the expected progression.  Burn time is double that of regular rcandy.  This may be due to extra moisture in propellant, more tests needed.  
Video
(1 meg .wmv file,
5 seconds of video
12-3-06B38-240 casing burning propellant made with Lyle's Golden Syrup and no other sugar.  Replication of 12/2/06B, primarily to see if slow burn rate would recur.  It did.

Peak Thrust: 45.5256 Lbs-force 
Average Thrust: 37.2838 Lbs-force (1)
Burn time: 0.74 Seconds (1)
Total Thrust: 27.65 Lb-Seconds
Total Thrust: 123.00 N-Seconds
Propellant weight: 0.1017 Kg 
Propellant weight: 0.224 pounds
ISP, Delivered 123.41 Seconds

Burn is a little quicker than in yesterday's test, but still far slower than with my usual KN/SU propellant.
Video
(1 meg .wmv file,
5 seconds of video
12-3-06C38-240 casing burning propellant made with Lyle's Golden Syrup and no other sugar.  Replication of 12/2/06B

Peak Thrust: 39.0970 Lbs-force 
Average Thrust: 28.9952 Lbs-force (1)
Burn time: 0.85 Seconds (1)
Total Thrust: 24.77 Lb-Seconds
Total Thrust: 110.16 N-Seconds
Propellant weight: 0.1008 Kg 
Propellant weight: 0.222 pounds
ISP, Delivered 111.52 Seconds

Very similar to 12-2-06B
Video
(1 meg .wmv file,
5 seconds of video
12-3-06D38-240 casing burning propellant made with Lyle's Golden Syrup and no other sugar.  Replication of 12/2/06B, 12/3/06B&C, but grain is molded a little larger in outside diameter, resulting in greater grain mass, and slightly higher Kn max.  

Peak Thrust: 48.7387 Lbs-force 
Average Thrust: 36.8039 Lbs-force (1)
Burn time: 0.83 Seconds (1)
Total Thrust: 30.82 Lb-Seconds
Total Thrust: 137.10 N-Seconds
Propellant weight: 0.1155 Kg 
Propellant weight: 0.255 pounds
ISP, Delivered 121.13 Seconds

Average of the four Golden Syrup propellant burn rates is 0.2535 inches per second.
Average of 4 equivalent tests with "normal" rcandy is 0.456 in/sec.
(tests # 1/29/06C, 1/29/06D & 4/1/06B)
Rate for 1 test burning KN/DX rcandy (4/16/06B) is 0.389
Rate for 1 test burning KN/SB rcandy (4/17/06B) is 0.261

So this "sucrose" based propellant is burning at approximately the rate of KN/sorbitol? That's weird.  More tests!

Video
(1 meg .wmv file,
5 seconds of video
12-10-06B18mm Model Rocket motor, 4 BATES grains catalyzed rcandy.  

Peak Thrust: 9.7590 Lbs-force 
Average Thrust: 5.5515 Lbs-force (1)
Burn time: 0.52 Seconds (1)
Total Thrust: 2.89 Lb-Seconds
Total Thrust: 12.86 N-Seconds
Propellant weight: 0.0149 Kg 
Propellant weight: 0.033 pounds
ISP, Delivered 88.08 Seconds

Fired in new bath scale II test stand, using INA125 amp C.  Jaggies in thrust curve are due to low resolution at this low thrust level. Deep dip near peak thrust is thought to be electromechanical artifact.  Good burn, good motor.
Video
(1 meg .wmv file,
6 seconds of video
12-17-06B38-240 casing burning propellant made with Lyle's Golden Syrup and no other sugar.  Replication of 12/2/06B, 12/3/06B, C, and D except that the grain ends are inhibited.  This creates a truly neutral burn profile, at least in the simulation.  

Peak Thrust: 62.3558 Lbs-force 
Average Thrust: 45.0877 Lbs-force (1)
Burn time: 0.61 Seconds (1)
Total Thrust: 27.62 Lb-Seconds
Total Thrust: 122.84 N-Seconds
Propellant weight: 0.1115 Kg 
Propellant weight: 0.246 pounds
ISP, Delivered 112.42 Seconds

In practice, we get a "saddleback" curve, reminiscent of those generated by a star grain.  I averages out more neutral than the fully uninhibited grains generated in previous tests.  The initial bump over 60lbf could have been due to the fuse paper pyrogen accelerating the burn briefly.  The later sharp peak might have been from the waning grain breaking up, or perhaps a piece of end-inhibitor passing through the nozzle. The promise of truly-neutral burn profile is intriguing.   It is an interesting challenge to get the "curve" to be truly flat.  I might take that one up.  
Video
(1 meg .wmv file,
6 seconds of video

Recrystallized Rocketry
Jimmy Yawn
jyawn@sfcc.net
rev 12/17/06