Small engine dyno

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Jun 18, 2020
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Hi Byron,
Do not TIG Braze the copper. Just Silver solder. Just as effective on your models, ands a lower temperature melt of the silver solder. Worth paying for the right stuff.
actually if you have good foot pedal control you can adjust the heat easily with the TIG. You have a controllable heat with a real inert covering gas I also have a double regulator so I can purge and have inert gas on bothe sides of the joints I do have real silver solder material too welding these 1/4” copper fittings would be a challenge even if I could see perfectly so I’ll go with the silver solder braze . I make a couple set up parts to get tuned in . I got some #10 32 brass nuts today so I drilled out a couple to 2/4 40 TPI ME and tapped them . It worked great. The tube and nuts actually sit nice and square on the fittings I’m working on a plug but my new roll of solder disappeared . I soldered a piece of wire then bent it around 180 compressed it a little and stuffed it in a stub tube . I fill it with solder then just screw the nut on perfect plug . I even got a bag of fiber washers
My die is indeed a straight cut so does not want to start nor even cut much more thread easily I guess I’ll just have to get a taper cut pipe die then chase it with the straight die. Apparently PMResearch changed something in their description. They don’t give these dies away . But I haven’t found anyone else I trust that has them . My supposed to be nice drill press is turning out to not be so good the chuck wrench that came with it is so heavily powder coated that it won’t go in the hole then after scraping and sanding the paint off the powder cat is so YHINK the gearvteath won’t engage properly . Then the chuck itself seems frozen or rust. Of course I don’t have my channel lock or pipe wrench here so my son said he would bring some over . Then I tried to get the Jacob’s taper loose but it’s stuck too. I’ll get a new one . I YHINK I saw a colt version . Also saw wher a guy drilled a hole in the spindle shaft tapped it and put a flat on the adaptor so it can’t just fall off. I’m about 5 steps away from putting this thing in the recycle bin and just get some kind of small mini mill . There are several that I could squeeze into my limited work area . I got a few brass chips in the carpet snd it was all the vacuum cleaner could do to get them out so I need a better chip guard I managed to squirt tap magic all over my new sweat pants I hope it comes out in the wash tonight . Nice weather. Rain cloudy . It’s the winter dreary days until spring.

Bak to soldering the plugs .


Ken I

Project of the Month Winner!!!
Project of the Month Winner
Oct 31, 2010
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Cape Town, South Africa
We call it JK class - using sealed can rules - Hawk 7's - the dyno can test up to Group12 and Eurosport classes.

Originally built for DC RC motors - it is no longer available.

Regards, Ken