tkatc

tkatc

Well Known Member
Just did my first flares today. The first one I did turned out to be a bit too wide despite using the depth stop as a guide. I also noted I could really crank down on the cone making it expand further than desired. This technique proved to make a flare which was too wide for the AN-6 fitting.

The second attempt I puposely inserted the tubing just shy of the depth stop and made certain not to crank down the cone to excess. This made a very nice fare that I assume is usable/acceptable.

My question is, how do you make consistent flares? Is this just a feel/sight type of thing? If you get it wrong does this introduce leaks?
 
lubricate and feel...

Make sure to use a small amount of lubricant on the mandrel... do a couple of scrap pieces and you will notice a consistent increase in resistance when making the flare... for me, this is just about the perfect stoping point.
 
Dont forget to remove all cutting marks from the end of the tube before flaring.

Scotch brite wheel works well to polish out marks.

And ditto on the lube.
 
Yes.
A little craftsmanship is required but clearly you already figured that out. You are a builder.
 
Hey T,

I second what Stephen said - use some lubricant, and stop the moment you feel the resistance change (increase).

As for the depth stop, I'm using the Parker tool and mine seems to be accurate.
 
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And once you "do it" guess what?

You ain't done!

Just wait until you have to flare a tube for the fuel system and then have to bend it to fit in the fuselage :eek:

Here's my "builder tip" - BUY A LOT OF TUBING! :D
 
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IMG_6726a.jpg


Good vs Bad
 
Tom, I'm using the Parker tool as well. Let me try a few more flares. Maybe I just over-torqued the horn the first time.

I'm no expert yet but it IS fun flaring the tubing. :D
 
I've found the cutting tool is important, don't smash down as you twist, go slow for a clean cut. The cheap Home Depot/Kobalt variety work as long as you GRADUALLY tighten down. Sharper is better though.

Then debur the inside, use a file to take off the edges on the outside, and a quick spin on the scotch bright wheel.

When flaring, tools vary how deep or proud to put the line to get a good seat on the collar. Some practice a few times you'll find it. My particular tool is dead flush.

As was mentioned, a drop of oil on the mandrel. I use marvel mystery air tool oil. Tighten down until you meet resistance, don't torque it down. Back off and voila!
 
Ditto all the foregoing, emphasize all the advice not to overtighten (ask me how I know). I'd be willing to bet if you run the tube up to the depth stop next time, and stop when you feel the resistance, and see the tube wall lay against the outside of the recess, your outside diameter will not be too large, assuming you have a quality tool. I would be very leery of using flares where the tube was not set up against the depth stop.
 
After doing a few flares yesterday using the advice on this forum, I have acquired the "feel" for that pressure everyone has mention but I failed to recognize on my own. It really is pretty fun to create nice flares.

I still have one question.... I check my flares against the AN fitting and they all match up nicely with the nipple but I have seen some that cover the entire nipple and some just shy of covering. In my mind they are all acceptable but I just wanted to run it past some experts.
 
flair diameter

Tony,

There is a specification for flair diameter SAE J533 3/8 aluminum tube should be
.484 +.000 -.010 This can be checked with a dial caliper.
 
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