Re: Bryan’s mini pot still
Posted: Fri Jul 27, 2018 11:55 am
G'day Guy's,
Well got the burner finished and working nicely, now for safety incase of a blow back in the burner I made a cover for the top opening and it does make the flame more consistent.
Now this is the first time I've made a burner and it has been a bit of fun trying out different pipes and making small frustums to aid in the air/fuel mix. Looking the spec's of lpg they reckon around a 25:1 air lpg ratio for the ideal burn. In one of my tests I moved the injector back away from the frustum and got a good blue burn. On measuring I was around 30mm short so just cut a longer length of 3/4" and soldered that inplace. Now the frustum at the gas end is a 3/4" to 1-1/2" and I found after drilling holes wasn't enough air to cut the top and bottom off got a heap better but still not good enough.
So I drilled 3 off 1/4" holes on the underside of the pipe and found the flame was much better but still had the yellow flame. So I cut the 2 holes to make a slot and tried it again and found YAY :happy-partydance: found the right air/fuel ratio to get the most out of the lpg with a good clean burn.
Now to start making burner one has to start at the gas input end and make the injector nozzle. I grabbed a 1/8" to 1/4" bspt fitting and found the internal hole was a tad under 5mm. So wacked a taper 6mm tap thru for the injector thread. This meant I could just use a M6 sockethead cap screw and drill a 0.7mm hole. Why 0.7mm well thats the smallest carbide drill I have :laughing-rolling:.
To hold the bspt fitting I used some 3mm brass plate and drilled/tapped a 1/8" bspt thread. Also I was able to hard solder the brass plate to the copper frustum.
Now the burner ring is 3/8" copper tube and I used my small tube bender to get a 60mm ID bend. I drilled a heap of 0.8mm holes on a 5mm spacing angle slightly in so the flames would point in to concentrate the burn.
For the legs I just used some 7x5mm copper and hard soldered them on.
As soon as my tax return arrives I'm buying an oxy bottle as LPG/Oxy will be way better for heating than the small propane bottles.
Cheers Bryan
Well got the burner finished and working nicely, now for safety incase of a blow back in the burner I made a cover for the top opening and it does make the flame more consistent.
Now this is the first time I've made a burner and it has been a bit of fun trying out different pipes and making small frustums to aid in the air/fuel mix. Looking the spec's of lpg they reckon around a 25:1 air lpg ratio for the ideal burn. In one of my tests I moved the injector back away from the frustum and got a good blue burn. On measuring I was around 30mm short so just cut a longer length of 3/4" and soldered that inplace. Now the frustum at the gas end is a 3/4" to 1-1/2" and I found after drilling holes wasn't enough air to cut the top and bottom off got a heap better but still not good enough.
So I drilled 3 off 1/4" holes on the underside of the pipe and found the flame was much better but still had the yellow flame. So I cut the 2 holes to make a slot and tried it again and found YAY :happy-partydance: found the right air/fuel ratio to get the most out of the lpg with a good clean burn.
Now to start making burner one has to start at the gas input end and make the injector nozzle. I grabbed a 1/8" to 1/4" bspt fitting and found the internal hole was a tad under 5mm. So wacked a taper 6mm tap thru for the injector thread. This meant I could just use a M6 sockethead cap screw and drill a 0.7mm hole. Why 0.7mm well thats the smallest carbide drill I have :laughing-rolling:.
To hold the bspt fitting I used some 3mm brass plate and drilled/tapped a 1/8" bspt thread. Also I was able to hard solder the brass plate to the copper frustum.
Now the burner ring is 3/8" copper tube and I used my small tube bender to get a 60mm ID bend. I drilled a heap of 0.8mm holes on a 5mm spacing angle slightly in so the flames would point in to concentrate the burn.
For the legs I just used some 7x5mm copper and hard soldered them on.
As soon as my tax return arrives I'm buying an oxy bottle as LPG/Oxy will be way better for heating than the small propane bottles.
Cheers Bryan