@Doug L In THIS post relating to an Optimus 9 cracked tank repair I wrote, Doug told me he had already worked on the Borde, drilling out the tip of regulating spindle that had jammed and broken off in the jet orifice. Here's how the tip of the component should look (photos courtesy of Hazet from his Stove Reference Gallery example). Here's the component on the Borde requiring repair. The absence of that tip isn't what prevents the stove from working properly. It's the fact that the jet hole is now oversized and whereas this should happen (patent drawing) ... ... there was no positive shut-off, the regulator spindle entirely disappearing into the jet orifice and not stopped at the tip of the jet. I first explored the use of short lengths of hypodermic needles to repair overly large lipstick burner jets HERE - an idea suggested by Doug appropriately enough. Consulting THIS chart of hypodermic needle gauges I saw that a 16-gauge needle has an outer diameter of 1.651mm and a bore of 1.194mm. That's just the right outer diameter to line the jet hole but smaller than the diameter of the regulator spindle. Here it is silbrazed in place. Excess needle trimmed off, jet seat squared off, regulator component in place. Fuelled up and fired up. Controllable and it can now be shut down! Mmm ... Should I? John
Hi John, Master of the Hypodermic, Tamer of the Borde, etc. Masterful resurrection of a desk paper-weight back to a fully-functioning blowlamp/stove. What a great post, and with a happy ending. I hope we can see some more flame shots once it gets dark. Best Regards, George.
Sorry I'm late on this post.Glad to see you were able to get it up and running John and with the hypodermic fix.I should have guessed.
Update I decided to return the regulator/burner plate to specification by restoring the broken-off tip. I took a short length of stainless steel wire (1.5mm diameter) and silbrazed it to the tip then machined it to a (roughly) triangular section with a hand-held Dremel and a diamond abrasive wheel. Makes no difference to the function - probably would if burning pump petrol and it had to ream the jet as mentioned in the patent to remove combustion coke - but it completes the restoration.
I was re-reading this great thread and was about to ask that question. Now answered. A great job, John. Ken in NC
@snwcmpr I've been using the Borde rather a lot - great stove, I can understand why it has an entusiastic following - and have been giving more thought to that 'reamer' tip. Going back to the patent I reproduced the illustration from that reamer function is clearly stated, to scrape away any coke deposits left by burnt fuel. Depending on the quality of the fuel (I'll be using Aspen exclusively) that reaming function could make the difference between the stove working or not. Without the reamer tip the jet outlet could block altogether preventing the release of a priming charge of fuel from the tank.
This does seem like such a simply well made, no frills, stove. Uncomplicated solutions. The reamer, not just a pricker, but a cleaner. Wow. I cannot fathom that someone doesn't pick up the baton and start making them again. @presscall that IS along the lines of the question I didn't ask.