Christer Carlsson presented here: NRV removal tips? a very nice home-made NRV extracting tool. It is simple and elegant. The only problem is the necessity to have a pump-lid to make a larger hole in it. No problem in Sweden, where ruins of classic kerosene stoves can be found everywhere behind the summerhouses. In most countries classic brass stoves are sold for very unreasonable prices, even if they are incomplete, damaged and beyond repair. No good source for parts like a pump-lid. I had to repair a Primus No.1 with blocked and damaged NRV. The stove is more than 100 years old, no question that the pump-lid must be left unchanged. I found a new solution. Here it is. The tool consists of a very short NRV-key with a square ¼" drive for a 5.5 mm socket and a 5.5 mm Allen key. This is the tool in parts. The Allen key just passes the unmodified hole of the pump-lid and is strong enough to transfer the torque. The raw material: a bolt 10 mm diameter, a steel pipe 10 mm inner diameter, 5.5 mm socket, Allen key and some washers 15.7/6.6/0.8 mm. A quadratic bit of plywood, fixed on the bolt, helps to grind exact square flanks. The slot for the NRV leaves only 2.5 mm steel at the sides. The pipe is necessary for strengthening the sides. How to use: the key with socket is set onto the NRV. Some washers fill the gap between socket and inner end of the pump-lid when the lid is screwed on the pump. Most pumps have almost the same length. The number of washers varies from pump to pump. Screwing on the lid. Ready to turn the key. I was very surprised how easily even the most stubborn NRV got free. After the first ¼ turn of the key, the lid is screwed off at the same time with the NRV. The NRV of the 100 year old Primus No.1. No chance to get it out with a standard NRV key, but no problem with the home-made special key! Regards Radler
Nice I like the method of indexing your flats using the ply square I've been acquiring materials to make the 'Carlsson Tool' , but I guess you won't be needing one with that little beastie Good job
Nice design Radler. It overcomes the problem of the varying threads and pump tube diameters used by some manufactures.
Oh, you... The 'Carlsson tool'... OK! It sure has a ring to it. Radler, I think you have done an excellent version of the non-slip tool. Good idea, and nicely done to share an easy way for people to make a tool for themselves.
hi Radler thanks for sharing the tool you made, it helped me make one too. I used a 10mm stainless rod. To make the 5mm slot I first drilled it with 4mm drill to remove material and then filed it until the non return valve fit snug. I filed the 1/4'' square shank. To prevent the slot from expanding under use I didn't have a 10mm ID tube like you used so I used a 3/8'' nut, drilled it with 3/8'' drill and reamed to 10mm but the nut was too loose on the shaft so I used retaining compound to fix it. How did you make the 5mm slot?
