Post by chris vine on Feb 25, 2008 8:35:26 GMT
I don't know if there will be any interest in the lamp saga? But here are some pictures and also the notes which were in another (wrong) thread.
these are of the lamps fitted to Bongo. The bodies were lost wax casting from Mr J Tipton. The burners, bulls eyes and all internal baffles and modifictations were made after much experimentation.
Gauge Glass lamp. This one is rather smaller than the main lamps, it is a shame I did not put a scale next to it in the photograph.
The notes from the other thread:
I managed to get the lamps on Bongo (admittedly 7.25" gauge) to work with tiny flames.
It is very difficult to get to work and several things are critical. Mainly the fuel you use. I tried for a long time with cellulose thinners (dont tell h and s) because it can produce a really tiny white flame. (parrafin gives a blue flame when very small).
You need a tiny flame because the real difficulty is getting the air in there.
In the end I found that the heavier oils were best because they burn with a white flame when small and also heat the wick up much more. This is a great advantage because the flame does not blow out so easily if the wick is really hot.
I found that steam oil worked well for a bit but there is too much crud in it and it polutes the wick soon. Interestingly this was also the trouble with the cellulose thinner. After a while the flame would start to sputter. I think there must be some component which is non flammable which builds up in the tiny wick.
For a wick you can use a single strand out of a greenhouse parrafin heater, available as spares in B and Q.
In the end the best fuel I found was White Oil. This is a heavier than normal lamp oil and it is usually used in those citronella midge candles when the other chemicals have been added.
Getting the airflow right is tricky. too much and they blow out in a draught. Too little and the don't work!
All in all this was a real mugs' game but fun all the same.
The lenses to go in the little lost wax cast lamps were no good because they were made of perspex and melted with the heat. In the end I "found" some old fashioned road cats eyes. The glass bulls eye can be machined with a tungsten tipped tool to fit the lamp. The white ones are easy. The red ones for the back are more difficult because these cats eyes are only found on motorway slip roads.........
I will try to load up a photograph or two of them in action in the next day or so.
I would really love to see someone perfect this. Mine do work and will often burn for an hour or two if you put new wicks in. However they are far from hurricane proof. In particular up or down drafts near them will put them out in a moment. The trouble is that there is almost no store of air in the lamp and they are so short that there is very little chimney effect to drive the air through.
Clearly you cannot scale nature, but maybe someone will get a design which works well. I know that Cherry Hill has made some of the lamps on here (much smaller) traction engines work. However she told me that she had to keep the doors open to let enough air in. (her padlocks work too!)
Chris.
these are of the lamps fitted to Bongo. The bodies were lost wax casting from Mr J Tipton. The burners, bulls eyes and all internal baffles and modifictations were made after much experimentation.
Gauge Glass lamp. This one is rather smaller than the main lamps, it is a shame I did not put a scale next to it in the photograph.
The notes from the other thread:
I managed to get the lamps on Bongo (admittedly 7.25" gauge) to work with tiny flames.
It is very difficult to get to work and several things are critical. Mainly the fuel you use. I tried for a long time with cellulose thinners (dont tell h and s) because it can produce a really tiny white flame. (parrafin gives a blue flame when very small).
You need a tiny flame because the real difficulty is getting the air in there.
In the end I found that the heavier oils were best because they burn with a white flame when small and also heat the wick up much more. This is a great advantage because the flame does not blow out so easily if the wick is really hot.
I found that steam oil worked well for a bit but there is too much crud in it and it polutes the wick soon. Interestingly this was also the trouble with the cellulose thinner. After a while the flame would start to sputter. I think there must be some component which is non flammable which builds up in the tiny wick.
For a wick you can use a single strand out of a greenhouse parrafin heater, available as spares in B and Q.
In the end the best fuel I found was White Oil. This is a heavier than normal lamp oil and it is usually used in those citronella midge candles when the other chemicals have been added.
Getting the airflow right is tricky. too much and they blow out in a draught. Too little and the don't work!
All in all this was a real mugs' game but fun all the same.
The lenses to go in the little lost wax cast lamps were no good because they were made of perspex and melted with the heat. In the end I "found" some old fashioned road cats eyes. The glass bulls eye can be machined with a tungsten tipped tool to fit the lamp. The white ones are easy. The red ones for the back are more difficult because these cats eyes are only found on motorway slip roads.........
I will try to load up a photograph or two of them in action in the next day or so.
I would really love to see someone perfect this. Mine do work and will often burn for an hour or two if you put new wicks in. However they are far from hurricane proof. In particular up or down drafts near them will put them out in a moment. The trouble is that there is almost no store of air in the lamp and they are so short that there is very little chimney effect to drive the air through.
Clearly you cannot scale nature, but maybe someone will get a design which works well. I know that Cherry Hill has made some of the lamps on here (much smaller) traction engines work. However she told me that she had to keep the doors open to let enough air in. (her padlocks work too!)
Chris.
