bonzoronnie

[quote name='cooperman435' date='Jan 12 2007, 03:30 AM' post='30431']
Has anyone ordered the powdered sulphur from garden direct?

Im just checking if anyone knows of its purity?


Another possible low cost sulpher powder can be obtained from your local agricultural merchant

Mine costs £6.50 for a 2.5kg Tub

Very finely milled

Its primary use if for dusting cattle hoofs and is of quite a high purity

All of the BP made with this sulpher has been of a good quality ( Hot & Fast )

And before anybody goes off on one.!! I did aquire a MSDS, Direct from the manufacturer before using this stuff

BTW anyone out there know enough about electronics to tell me how to work out the power requirements of the motor so I can search for a suitable power suply? 3 hours with a 1 hour down time is boring to have to keep remembering on and off times?

I also use a 12v dc motor for my mill

I use the 1.3L jar from inoxia with 1kg of media

The power requirement for this motor is just above 4.6v dc ( below this the motor will stall)

I have achieved this by using a fixed resistor of 1 Ohm. and a further Variable resistor of 1 Ohm Max

Running at 1.75 ohms resistance, the mill seems to turn the mill at a reasonably slow speed. I do not experience too much trouble with clumping.

I guess, If you can find a 6v dc power supply, Very little extra resistance would be needed

Motor cycle battery charger seems to spring to mind

Hi to all that have made posts on this topic.

I am pleased to find that I am not alone. As I too, have been making use of PVC tubes.

The power to weight ratio over paper tubes must be quite substantial.

I resolved the problem of the tube distorting when the nozel was rammed by making use of a 15mm id brass ferral. Namely a standard 15 mm compression fitting. The beveled olive edge was removed to leave it nice and flat.

For an extra bit of grip I found a coarse threaded tap, slightly larger than the id of the tube and cut a few mm of thread.

As I am making end burners, I can ram the nozel plug and the first two powder rammings before I remove the tube from the ferral. I then continue to fill without the ferral.

I think the PVC tube is incredibly stong in view of the relative thin wall thickness

Inoxia sell 1/2" ID tubes.

Indeed they do. Many thanks for that

I'll be sure to order some soon.

I must say I have to agree on the biodegradeable issue raised in the use of plastic tube.
I did give this due thought before taking this route.

First and foremost was the safety issue. I have been unable to source any 1/2" id paper tubes in the uk. Plenty of 3/4" available but this means more BP production and an even bigger bang if all turns pear shaped .

Perhaps other members know of a UK source of 1/2" tube.

As I said I am new to this hobby. I raised the subject to get other members views as to the safety issues of plastic tube.

I have no intention of adding a payload to any of my rocket motors until the full safety aspects are understood. I do not really want to move up to 3/4" tube just yet.