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Having trouble flaring fuel vent line

I'd wait for the Rolo tool, which is a knock off of the original Parker tool. It just works. Mine is an old one and I think has a finer thread pitch than the Rolo, but pretty sure with the care you are excercising in your method, you will be super happy.

All of those samples show witness marks down the side that to me don't look normal at all. I suspect over pinching of the tube and/or the tube being slightly compressed or triangulated enough to allow one side to bias....

The parker tool won't do that. I'd wait.

Steve.
 
stigaro said:
Hate to say it, but get the Rolo-Flair.
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Yep, I ordered it last night! Now I just have to wait a week for it to arrive. I'm still waiting for more tank sealant from Vans so I'm in a holding pattern on the fuel tanks anyway.
 
bertschb said:
Yep, I ordered it last night! Now I just have to wait a week for it to arrive. I'm still waiting for more tank sealant from Vans so I'm in a holding pattern on the fuel tanks anyway.
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while you are waiting... scotch brite on each rivet line inside the tank and on the mating surfaces of the rib, It seems counter intuitive that roughing up the surface helps, but it truly helps promote surface adhesion. I etch and conversion coat the inside of my tanks for even more surface adhesion...just gotta be super clean.

The tanks are the hardest part of the build, in my opinion. patience and cleanliness are everything. clean and prep like a fool. till not a spec of dust...(oil, like from your fingers is bad).
I literally wear white cotton gloves while doing my last wipe down with Isopropyl alcohol.

Popsicle sticks are super handy for spreading goo...I measure out my adhesive by weight...this is a bad place to estimate. A one gallon coffee can with a cup or two of MEK and a lid, is super handy to throw your gooey clecoes into...let them soak overnight and clean up the next day is a cinch.

You got this...final word of un-solicited advice...slow and exacting. The neater it all looks when you are done...the better.


Steve
 
Freemasm said:
On another note, having mismatched flare angles between male/female faying surfaces is an accident waiting to happen. May pass a leak test but what was a distributed load (2D) is now more of a point load. Without said distribution, future crack development potential has risen exponentially. Additionally, if the joint/torque is used to make the parts conform, you've just cold worked the material at it's point of highest stress. Successful time at condition isn't relevant unless it is tested beyond the expected life of the system (aircraft). It's good until it (suddenly) isn't.

Build safe. Fly safe.
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Winner winner chick'n dinner. The mismatch causes "induced stress" which in aircraft structural analysis = very low fatigue life. Leading to cracking.
 
steveandmaysrocket said:
while you are waiting... scotch brite on each rivet line inside the tank and on the mating surfaces of the rib,
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Thanks Steve. Yes, I scuffed the rivet lines and rib flanges. Rinsed all the rivets with MEK. Masked off everything I didn't want sealant on. Wiped down the surfaces with Acetone before applying sealant. Used a scale to weight the sealant. Went through a couple hundred gloves and probably twice as many lint free towels. Used popsicle sticks to spread sealant on the ribs and to form the beads around the ribs. Used syringes to apply sealant to the shop heads. I actually bought a Semco gun and a bunch of sealant tubes/tips but didn't use it. I found the syringes worked well. I may try the Semco gun on the rear baffles.

All I have left is the vent tube, aft inboard (half) rib and rear baffle. I'm building ER fuel tanks and have quad CiES senders.
 
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Bummer. I haven't seen anything like that with mine, so I think you got a defective unit. I'd check into returning it under warranty (factory defect). It's definitely not working as it should.
 
I actually enjoyed building the tanks and found Proseal much nicer to work with than epoxy resin, silicone sealant or even driveway sealer (I did all 4 things in one week). Just plan things out ahead of time and don't rush.
 
stigaro said:
Just plan things out ahead of time and don't rush.
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I'm definitely not rushing. It took me an average of about 2.5 hours per rib. I probably spent 2 of those 2.5 hours wiping off my gloves and tools. REALLY glad to be done with the ribs and I'm going to throw a party when I'm done with these stinking fuel tanks - assuming they don't leak.
 
stigaro said:
I actually enjoyed building the tanks and found Proseal much nicer to work with than epoxy resin, silicone sealant or even driveway sealer (I did all 4 things in one week). Just plan things out ahead of time and don't rush.
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Thread drift - Same. I dreaded the tank build for no reason. After my less than stellar riveting results with wet proseal (just because I'm a rookie, I'm sure all of the seasoned folks will say it's easy), I went the dry riveting route for the ribs where you cleco/clamp the tank up tight and let the proseal set for a day or so before riveting. That made all the difference in the world and I'm positive gave me much better rivets, let alone being MUCH less messy. That process took my stress level down 100 notches for the tank build. Leak free, minus one small corner rear baffle spot that I didn't put enough proseal on.
 
Jjackh10 said:
Everyone is focused on their favorite tool. Ridgid makes good tools. 2 things might be causing this.

The OP mentioned the tubing had been bent then straightened. That changes the wall thickness a tiny bit around the circumference. So the flaring tool is trying to flare different thicknesses.

Second, that tool is made for copper so the "clutch" is probably too tight. Try stopping before the clutch slips.
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Van's ships the tubing formed in a circle for packaging purposes. So, everyone starts this way.... and needs to straighten.
 
bertschb said:
This makes me wonder if the same side of the cone hits the same side of the tube flare with each rotation. IOW, if the "wider" sweep of the cone always hits the same area of the flare towards the end of the flaring operation, it seems this might disproportionately squeeze that side of the flare to the point where it's taller (and thinner) than the opposite side of the flare.

I don't know if that makes any sense but the die itself doesn't look malformed to this untrained eye.
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I'm guessing the tooling cone does not rotate. I say this because in the parts drawing it depicts a thrust bearing between the cone and the shaft.


My theory is once the cone is in contact with the tubing the thrust bearing allows it to remain stationary (not spin) as the shaft is turned to form the flare. I would guess that there is misalignment between the centerline of the tooling cone and the clamping bar that holds the tubing.
 
And don't forget to lubricate the Rolo-Flair cone area that makes the flare. I just use my air tool oil because its handy and I don't want to pick grease out of the tubing.
 
Webb said:
It doesn’t stop rotating.
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That's what I figured - and that's what it feels like when rotating the handle. And come to think of it, the instructions say to continue turning the handle two more full rotations after the clutch releases "to ensure a uniform, smooth flare surface." So yeah, it's still rotating.
 
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PhatRV said:
No problem after 80 hours of test flying. The tubing is soft aluminum and it will conform to the AN surface.

If you have a flying airplane and you find leaks: use this type of AN seal so you don't have to redo the fitting,
www.aircraftspruce.com

Del Fitting Seals Aluminum | Aircraft Spruce ®

Del Fitting Seals Aluminum DEL fitting seals are designed to eliminate leakage due to scratches on the sealing surface, improper torquing, or poor finishes on tube ends, in high or low pressure applications. For use with ...
www.aircraftspruce.com www.aircraftspruce.com
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Aluminum?

The ones I purchased and used decades ago were copper. I always use them when connecting a steel line to a steel fitting. (Stainless steel governor line and steel AN fitting.) Seen too many leak or weep not to use the seal.
 
RV6_flyer said:
Aluminum?

The ones I purchased and used decades ago were copper. I always use them when connecting a steel line to a steel fitting. (Stainless steel governor line and steel AN fitting.) Seen too many leak or weep not to use the seal.
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I am novice at airplane. I have always used the flexible aluminum tubing, and haven’t used the copper tube yet
 
bertschb said:
How do you use these things? Just you just set them on the male AN fitting and connect the tube then tighten the nut down?
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Basically, yes. The slightly better way...is to stick them to the AN fitting with a slight bit of Fuel Lube on both sides...then rather than torque them up in one fell twist, to sorta settle them into the final torque, meaning if final torque is 75 lb. in....do an initial at 25, then 50 then 60, 70 and 75...

that's sorta my routine.

you won't get many sleepy fittings.


steve
 
steveandmaysrocket said:
Yep....that's good stuff for nearly every AN fitting on, in or near, your fuel system. Works for O rings, AN fittings, flares and beads...just gotta have it, kinda stuff.

Steve.
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Realize that fuel lube is NOT a thread sealant. Don’t use it in NPT fittings.

Also, nothing is required to be used on AN fittings or flares. A properly executed flare is assembled dry and will not leak.
 
bertschb said:
I'm using a flaring tool for the first time on my fuel tank vent line and I don't like the results. After eight attempts with the same results I'm getting pretty frustrated. I'm using a new Ridgid Model 377 flaring tool. The instructions say "Once the clutch releases, turn the handle at least two more full rotations to ensure a uniform, smooth flare surface". I've tried that along with no additional turns and 4-5 additional turns. Same results. The flare surface looks fine to me. If you look at it from the end, it looks great. It's the uneven sides of the flare that aren't right.

The only thing I can think of is the piece of scrap tubing I'm using to practice these flares on was used to practice bending the tube as well. Some parts of it have been bent then straightened then bent again. Could that have caused the walls of the tubing to be uneven in some places leading to the uneven flares?

Before I flare, I cut the tube with a Ridgid tube cutter. When using the cutter I gently advance the knob after every couple of rotations to minimize deforming the wall of the tubing while cutting. I then use a very small round file to gently debur the inside of the tube. After that I use a small flat file to smooth the end of the tube. Finally, I use a purple Scotchbrite pad to debur.

Any ideas as to what I'm doing wrong?

View attachment 70227


View attachment 70228
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I have a RFT37 also and its great for flaring. The issue I see is the tube isnt square on the end, and after flaring it looks lopsided. You can do this--before flaring, put the tube in backwards in the flare bar so you have a flat surface to square the tube with. Use a fine file to square the tube. Another quick way is a belt sander, but it need to be exactly 90* and the belt need to be really fine, or you'll have minor imperfections on the end. 3rd and maybe the best--if you have a lathe, just remove a very smal potion of the tube in the lathe, basically making a squared end. That works. As far as the flaring operation, the flare bar has a pretty tight pivot joint to make sure the 2 halves are correct--but you might look and see if the flare cone housing where the thumb screw is--see if its cocked just alittle and not allow the housing to be square to the bar. There is alittle pay in there so you can move the bar---possibly that clearance is allowing the housing to be tighened off square.
 
TS Flightlines said:
The issue I see is the tube isnt square on the end, and after flaring it looks lopsided. You can do this--before flaring, put the tube in backwards in the flare bar so you have a flat surface to square the tube with. Use a fine file to square the tube.
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Thanks for the feedback Tom!

The end of the tubing on all 12 previous attempts looks square to me. I'm using this tool to cut the tubing:
IMG_0358.jpg

But, I did as you suggested and put the tubing into the tool backwards and extended it past the bar just a tad. I then filed it flat, polished it with a Scotchbrite pad and gently deburred the inside - as I've done on all previous attempts. As before, the end looks square.
IMG_0360.jpg
I then proceeded to flare the tubing per the instructions. The results are the same as the previous 12 attempts and the high side is on the same side of the tool as the previous 4 that I marked.
IMG_0362.jpg

Needless to say, I will not be using this tool and will instead test the Rolo-Flair when it arrives next week. Hopefully the results will be better!
 
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Going out on a limb but I would say the cone isn’t centered. There is a set screw on the side I suspect is causing this. You will get a perfect flare on your first attempt. Afterwards, sell the Rigid on eBay or deposit it in the nearest waste receptacle.
 
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Webb said:
Afterwards, sell the Rigid on eBay or deposit it in the nearest waste receptacle.
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I learned Ridgid has a "lifetime" warranty on this tool. Their website says to return to the place of purchase for a warranty claim. I'm going to take it back to Home Depot this afternoon and see what happens.
 
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It looks like a manufacturing defect. Either the cone is set at an angle (leaning towards the fat side) or it's off center from the hole. I have used the sister tool (the 45° one) and it works great.

That said, the Parker Rolo-Flair is a better, more enjoyable tool for only a bit more money. It has a built in stop to set the tubing's position and it will do 1/8" tubing should you need that. The one-piece design is a lot easier to manage than the two piece of the Ridgid. And the cone has lobes instead of an offset and it's also a bit smaller.
 
steveandmaysrocket said:
I'd wait for the Rolo tool, which is a knock off of the original Parker tool. It just works. Mine is an old one and I think has a finer thread pitch than the Rolo, but pretty sure with the care you are excercising in your method, you will be super happy.

All of those samples show witness marks down the side that to me don't look normal at all. I suspect over pinching of the tube and/or the tube being slightly compressed or triangulated enough to allow one side to bias....

The parker tool won't do that. I'd wait.

Steve.
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Parker is the manufacturer of the Rolo-Flair. It’s not a knock off.

 
bertschb said:
I learned Ridgid has a "lifetime" warranty on this tool. Their website says to return to the place of purchase for a warranty claim. I'm going to take it back to Home Depot this afternoon and see what happens.
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And toss some of your samples in the box.....
 
gasman said:
And toss some of your samples in the box.....
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Hah! I actually brought a bag of my failed flare samples to Home Depot to show the gal at the return counter. Unsurprisingly, she didn't care. In fact, she never even looked in the box. I could have returned a box of rocks. But, she did give me a refund! Now I wait for the magical Rolo-Flair device that everybody raves about.
 
bertschb said:
Hah! I actually brought a bag of my failed flare samples to Home Depot to show the gal at the return counter. Unsurprisingly, she didn't care. In fact, she never even looked in the box. I could have returned a box of rocks. But, she did give me a refund! Now I wait for the magical Rolo-Flair device that everybody raves about.
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I use the same cutter that you pictured. And I use the Rolo-Flair with very good results. You are headed in the right direction.
Good luck.
 
bertschb said:
I'm using a flaring tool for the first time on my fuel tank vent line and I don't like the results. After eight attempts with the same results I'm getting pretty frustrated. I'm using a new Ridgid Model 377 flaring tool. The instructions say "Once the clutch releases, turn the handle at least two more full rotations to ensure a uniform, smooth flare surface". I've tried that along with no additional turns and 4-5 additional turns. Same results. The flare surface looks fine to me. If you look at it from the end, it looks great. It's the uneven sides of the flare that aren't right.

The only thing I can think of is the piece of scrap tubing I'm using to practice these flares on was used to practice bending the tube as well. Some parts of it have been bent then straightened then bent again. Could that have caused the walls of the tubing to be uneven in some places leading to the uneven flares?

Before I flare, I cut the tube with a Ridgid tube cutter. When using the cutter I gently advance the knob after every couple of rotations to minimize deforming the wall of the tubing while cutting. I then use a very small round file to gently debur the inside of the tube. After that I use a small flat file to smooth the end of the tube. Finally, I use a purple Scotchbrite pad to debur.

Any ideas as to what I'm doing wrong?

View attachment 70227


View attachment 70228
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Brian,
As posted before it looks like the die is out of square, or the tube is not cut square. Additionally, I always wipe the die clean before each flare and put a drop of light oil on the die before turning in. Debur the tube inside and out as well.
Good luck.

Bruce
 
Breezy said:
Brian,
As posted before it looks like the die is out of square, or the tube is not cut square. Additionally, I always wipe the die clean before each flare and put a drop of light oil on the die before turning in. Debur the tube inside and out as well.
Good luck.

Bruce
Click to expand...
Hi Bruce

The tool was defective. The tube was square in all 12 attempts and yes I debur the tubing inside and out prior to flaring. See post #75 above.
 
Webb said:
Results?
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Well...I ordered the Rolo-Flair on the 11th. It supposedly shipped on the 12th (CA to OR) but it still hasn't arrived. I contacted Aircraft Spruce three days ago to let them know it was likely lost in shipping because according to UPS they never received it. UPS has now started an investigation to track it down. I have no idea how long that takes nor how long it will be before Aircraft Spruce ships me another one. I'm guessing I won't see the new flaring tool for another three weeks - if I'm lucky. I ordered some tank sealant and extra tubing from Vans two weeks ago and that still hasn't shipped.

These incessant delays (supplies from Vans, this tool, Beringer brakes, Finish kit, engine, etc) are killing my build and my mojo.
 
bertschb said:
Well...I ordered the Rolo-Flair on the 11th. It supposedly shipped on the 12th (CA to OR) but it still hasn't arrived. I contacted Aircraft Spruce three days ago to let them know it was likely lost in shipping because according to UPS they never received it. UPS has now started an investigation to track it down. I have no idea how long that takes nor how long it will be before Aircraft Spruce ships me another one. I'm guessing I won't see the new flaring tool for another three weeks - if I'm lucky. I ordered some tank sealant and extra tubing from Vans two weeks ago and that still hasn't shipped.

These incessant delays (supplies from Vans, this tool, Beringer brakes, Finish kit, engine, etc) are killing my build and my mojo.
Click to expand...
The only issue I have with the RoloFlare is the length of the dies. In some of our tubes, have a long die would interfere at the bend. So the idea we came up with was the best compomise between all the tools, and the fact that we were planning on repetative production. We we have this---I DONT recommend a builder have one---unless you have thousands of tubes to do. WE had the manufacturer custom make the dies with a large relief in the aft side so a previously bent tube and be inserted an flared close to the bend.
On your Rigid tool---something is off---is there an alignment pin on the open side?
 

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Update (finally):
I finally received my Parker Rolo-Flair today. My first attempt creating a flare was better than the previous 14 attempts with the Rigid 377. I'm going to experiment more with it tomorrow but I'm happy with my first try. The only thing I'm not happy about is this means I need to resume working on the fuel tanks.

IMG_0530.jpg
 
bertschb said:
Update (finally):
I finally received my Parker Rolo-Flair today. My first attempt creating a flare was better than the previous 14 attempts with the Rigid 377. I'm going to experiment more with it tomorrow but I'm happy with my first try. The only thing I'm not happy about is this means I need to resume working on the fuel tanks.

View attachment 71160
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I'm not sure if the picture is grainy, or might be my computer...but it looks to me, like you are over flaring that flare. I lightly scotch brite the OD when I do mine...then I grease the end I'm flaring up nicely with lube of choice...then flare, then cleanup. The OD shouldn't show any indentations or physical damage of any kind, if it does, you are either clamping with too much pressure, or flaring with too much pressure...the back and forth thing for 6 to 8 gentle, slow oscillations, till you have a fully formed flare. The Parker tool, really works best with only fingertip pressure....way less than many people think is necessary. Any cracking on the end of the flared tube should be filed off.. and I use a 3m buffing wheel on one side of my pedestal grinder to LIGHTLY...clean things up, if there's any indication of smears or tears...the formed radius at the intersection of the flare doesn't need to be a hard intersection point...if you test your flares on a fitting...I use an Enerpac with hydraulic fluid, you will find that a flare that is ever so slightly under-flared, will provide better sealing than an over-flared one. I guess what I'd say is I torque my Parker up, by holding the handle with my thumb and first and second fingers, right adjacent to the center shaft. I doubt I am putting more than 15 lb./in final torque on it..as soon as you feel it begin to snug in the slightest....stop and test that flare. Pretty sure it will be perfect.

That sample looks an order of magnitude better than the previous ones...nice job. Think Gentle.


Steve.
 
Yeah, it was my first attempt. I'm not done experimenting!

There are a couple things that seemed a little goofy. One is the "depth gauge". You are supposed to insert the tube until it touches the depth gauge. Mine touched the cone before the depth gauge. No matter how much I fiddled around with the cone, the tube touched it before the depth gauge. Maybe it works as advertised for larger diameter tubing? Probably operator error. The second thing is the instructions say something like turn the cone until resistance is felt then stop. That is super vague. It would be waaaaay under flared if I stopped flaring when I felt resistance. Since there is no clutch like the Rigid 377, I will need to experiment to see how much flaring is needed to get the right diameter.

I am probably tightening up the clamp too tight. I'll experiment with less clamping force tomorrow. I do clean up the OD with a Scotchbrite pad before flaring. I also used a drop of oil on the cone. The MAIN thing I was trying to achieve today was just a uniform shape around the circumference. Now that I have a tool that will do that, I can fine tune my technique to get a good flare. I plan to fiddle around with it more tomorrow. Less clamping force, lots of slow rotations back and forth....
 
Over the years, I have developed an affinity for Sulflo Plastilube Moly #3 grease. It is a high sulphur grease, that works REALLY well on aluminum when forming. I Q tip a blob onto the cone and a pretty good slather on the OD and even a little booger of it, in the ID.
I first found this product when we were deep-drawing aluminum cans for for emergency lighting bases and it works wonders on just about any aluminum forming process, from spin forming, to hydro forming, deep drawing or even bulge forming, we use it daily on virtually any method of advanced manipulative forming on aluminum.

S.
 
bertschb said:
Yeah, it was my first attempt. I'm not done experimenting!

There are a couple things that seemed a little goofy. One is the "depth gauge". You are supposed to insert the tube until it touches the depth gauge. Mine touched the cone before the depth gauge. No matter how much I fiddled around with the cone, the tube touched it before the depth gauge. Maybe it works as advertised for larger diameter tubing? Probably operator error. The second thing is the instructions say something like turn the cone until resistance is felt then stop. That is super vague. It would be waaaaay under flared if I stopped flaring when I felt resistance. Since there is no clutch like the Rigid 377, I will need to experiment to see how much flaring is needed to get the right diameter.

I am probably tightening up the clamp too tight. I'll experiment with less clamping force tomorrow. I do clean up the OD with a Scotchbrite pad before flaring. I also used a drop of oil on the cone. The MAIN thing I was trying to achieve today was just a uniform shape around the circumference. Now that I have a tool that will do that, I can fine tune my technique to get a good flare. I plan to fiddle around with it more tomorrow. Less clamping force, lots of slow rotations back and forth....
Click to expand...
when you slide the tube into the tool, you rock the wing nut on the clamp, OPEN, which rotates the stop into position to contact your tube end. Then holding the clamp halves together with your fingers, holds the tube in location, as you rotate the stop out of the way, and lightly clamp the unit onto your tube. I find that pulling the tube back off the stop maybe .005" (just enough to see a light gap) works best on my unit.

Then do the flare.

S.
 
I removed the stop. I found it did not produce proper flares and a real PITA. It also has the potential to mar the end of the tube. Put a mark 3/4” from end of tube and align that with the bottom on the clamping die. That will get you real close to proper flares regardless of tube size. Adjust as required. As others have mentioned, lots of lube. I use Vaseline. Use a fitting and the attached chart to get the flares the proper od.
20240913_161951.jpeg
Watch that the tool doesn’t leave marks like my new one did. I had to file my clamping dies on a brand new tool.
20230123_140126.jpeg
 
Here is another picture of the first flare I made last night compared to the sleeve. My understanding is the diameter of the two should be about the same, correct?
EDIT- Just looked at the chart that Todd B posted above (thanks Todd!) and the first flare (below) was 9.2mm so it's a little too large. Max is 9.14mm. The sleeve is 9.7mm.

IMG_0536.jpg

I made a second flare this morning following the instructions to "drive cone into tubing until slight resistance is felt - NO FURTHER!" As I suspected, this flare was smaller in diameter at 8.3mm - below the 8.64mm minimum spec for 1/4" tubing.

As for the "stop" (depth gauge), I used a magnifying glass this morning and if I carefully moved the cone into juuuuust the right position, the tubing did indeed just barely contact the stop so I was wrong about that. But, you definitely can't just push the tubing in and expect it to hit the stop on the first attempt (unless you're lucky). You have to wiggle the cone so the tubing doesn't touch it before the stop.
 
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I am so glad I went with the double flare tool…

Reading these comments, a huge amount of variability to the quality of each flare is possible. There has been many, many threads about risk mitigation on these boards, yet people are more than willing to risk a faulty flare, used in a pressurized fuel system, within the cockpit.

An interesting observation.
 
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