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Dan2+2
11-28-2005, 12:00 AM
Any tips on forming the 3/8 channel other than cutting pie slices and then welding them shut? When I try to hand bend the curve at the bottom corners of the fuselage it spreads out and kinks. Seems like there has to be a better way.

kimballforrest
11-28-2005, 12:17 AM
Go to your local hardware store and buy a pair of crimping pliers that are made for sheet metal/ducting installations. They are used to put the "corrugations" on the end of stove pipe. They will put a series of small side by side crimps in the channel and you can form any curve you want. Some guys put different thickness spacers in between the jaws to adjust the width of the crimps.

Dan2+2
11-28-2005, 12:22 AM
Sounds like a trip to the hardware store tomorow.

Cub junkie
11-28-2005, 12:27 AM
Dan you can also weld some round stock(cut off bolts) to some old pliers. You can copy a set like Avery or Cleveland Tool sells for 40 bucks. Just look at the pictures on their web site and copy. Kevin

Bugs66
11-28-2005, 02:06 AM
I JB Weld the round stock to pliers. My homemade fluting pliers haven't failed yet.

For the 3/8 channel though, seems you would need something pretty narrow. Maybe the duct pliers are the best.

Cub junkie
11-28-2005, 02:26 AM
I JB Weld the round stock to pliers. My homemade fluting pliers haven't failed yet.

For the 3/8 channel though, seems you would need something pretty narrow. Maybe the duct pliers are the best.
1/4" long bolts with the head and threads cut off welded to the pliers fits into 3/8" channel just fine.

Dan2+2
11-28-2005, 01:44 PM
Thanks guys, so now I will go look at the pliers at the hardware store, if cheap I will buy. If not I will make them.

redrooster
11-28-2005, 02:13 PM
A friend of mine has a "stretcher" and a "shrinker" for radius'ing angles and channels. He's doing an engine upgrade on a Swift, and has used it for many small parts that he's had to fabricate. I think he borrowed it from an A&P friend.
I'm a sheet metal worker (building construction- HVAC, siding/roofing, etc) and have worked in commercial fabrication shops as well as on jobsites, but never saw a set of tools like this. But they seem to work waaay better than using a set of handheld crimpers for this application.
I can't remember just how the tools are configured, but as I recall they have a set of jaws that grasp the material & a handle to apply the elbow grease. You hold the tool in a vice. Check with your local aircraft restorers/fabricators.

Rooster

behindpropellers
11-28-2005, 02:29 PM
Great site for metal fabrication:

www.metalmeet.com

Tim

PT6114A
11-28-2005, 10:55 PM
Using a shrinker is an easy and fast way to form curved flanges/channels. One word of caution though....take your time and shrink the metal a little bit at a time. You will need to make several passes, but it will work and look great when you are done. If you shrink/stretch the metal too much with each application, it will crack. Also, after using the shrinker/stretcher, use a die grinder with a scotch-brite wheel and smoothe out the marks left by the jaws of the shrinker to remove stress risers. Practice on a bunch of scrap material to learn just how far you can push the material before it cracks.
Cheers,
Chris

Pat Bowers
11-29-2005, 08:30 PM
Unfortunately the shrinker stretcher won't work on the small channel, only on angle stock. At Legend we make a form and bend it around using a hammer to flatten the kinks. If you have to make a tight bend the crimpers are the only way I know of. Pat at Legend

flybynite
11-29-2005, 11:03 PM
Fill the channel with a mix of epoxy and lightweight filler, let it set up then bend away. I was able to get a 4"radius bend with no buckling. Then, use a propane torch to heat to channel & scrape out the softened epoxy. I used some old WEST system & colloidial silica filler & bent around a plywood form.

Wayne

Cub junkie
11-30-2005, 10:31 AM
[quote="Pat Bowers"]Unfortunately the shrinker stretcher won't work on the small channel, only on angle stock. At Legend we make a form and bend it around using a hammer to flatten the kinks. If you have to make a tight bend the crimpers are the only way I know of. Pat at Legend[/

This is the same way my friend does the Piper channel, he is a former contractor for Wag Aero. He also does the rear window "D" frame channels a real efficient way, he starts out with the straight channel and a steel pattern the shape of the D window and stretches them around the male die with a thick steel female shoe, this is done with a cheap Harbor Freight muffler cutter air gun.

Bugs66
11-30-2005, 01:38 PM
...This is the same way my friend does the Piper channel, he is a former contractor for Wag Aero. He also does the rear window "D" frame channels a real efficient way, he starts out with the straight channel and a steel pattern the shape of the D window and stretches them around the male die with a thick steel female shoe, this is done with a cheap Harbor Freight muffler cutter air gun.

Can your friend make me a set of D frames? How much?

Dan2+2
11-30-2005, 02:44 PM
Cubjunkie, do you have any pictures of the pattern and female shoe? The 2+2 plans show a square window but I like the look of the cub window best. How is your project going? I almost have the floorboards done on mine.

Cub junkie
11-30-2005, 04:40 PM
To Bugs, yes he will sell them reasonable, I will check for a price. I did notice they looked a little better made than the Univair set I saw. Dan 2+2 , this man lives within a short cub flight (or drive)from you Leitchfield,KY his name is Ralph Fentress. He has a lot of Piper related patterns and works reasonable. He used to do a lot of sub contracting for Wag Aero many years ago but they got to pinching him on price so they parted ways. I dont have any pics of any of Ralph's stuff. I dont have any pics. of my stuff except "old" 35mm pics. Im not in the digital age yet,maybe after Santa comes this year. Kevin

Dan2+2
11-30-2005, 05:11 PM
Cubjunkie, Litchfield is pretty close to me and I may want a pair of the window frames too when you check on prices. My cousin married a girl from Litchfield. Can I/we get a list of what parts he makes for cubs?

behindpropellers
11-30-2005, 05:16 PM
I would like to get a list too.

Tim

Longwinglover
11-30-2005, 06:14 PM
I have been to Ralphs shop and seen his work. The shop is adiquate (but more like a large home workshop) but the quality of Ralphs metal work is very high. Ralph is getting on in years and I don't know how much work he is still doing. The one thing I will warn you about is because he is a one man show, if he doesn't have on hand, he can be as slow as Christmas! :lol:

Good luck,

John Scott

raspraker
11-30-2005, 06:56 PM
...This is the same way my friend does the Piper channel, he is a former contractor for Wag Aero. He also does the rear window "D" frame channels a real efficient way, he starts out with the straight channel and a steel pattern the shape of the D window and stretches them around the male die with a thick steel female shoe, this is done with a cheap Harbor Freight muffler cutter air gun.

Can your friend make me a set of D frames? How much?

Bugs: Ralph gets $27.00 a pc. for the D Frames

cubframes.com

Cub junkie
11-30-2005, 08:12 PM
I have been to Ralphs shop and seen his work. The shop is adiquate (but more like a large home workshop) but the quality of Ralphs metal work is very high. Ralph is getting on in years and I don't know how much work he is still doing. The one thing I will warn you about is because he is a one man show, if he doesn't have on hand, he can be as slow as Christmas! :lol:

Good luck,

John Scott

I go to Ralph's shop once or twice a month. He may be getting on in years but years of experience has made for good parts. His shop is a one man show, but he shows up early in the morning when I cant drag my butt out of bed and he gets things done. He has a lot of tooling that works for many Piper related parts. Just how long ago were you at Ralph's?

Cub junkie
11-30-2005, 08:18 PM
Dan 2+2 Im going to Ralph's monday and I will find out some of his prices. He probably has never had a list but Im sure he can tell me all he has to build/offer and I will write it down and relay. He is unemcumbered by computers and telephones as he has none in his shop. I will PM you when I know something. Kevin

Dan2+2
11-30-2005, 08:18 PM
Cub junkie, If you wouldn't mind some company I woul like to met at Ralph's shop if on a friday or sat. sometime. Its always good to see how other guys do things.

Cub junkie
11-30-2005, 08:24 PM
Dan 2+2 would be glad to introduce you to Ralph and meet you myself. will PM you soon about doing this. Kevin

Dan2+2
02-01-2006, 11:06 AM
I put a picture of the fluting/crimping pliers I made in my album if you are interested.

Gordon Misch
02-02-2006, 01:29 AM
Dan, I couldn't find your pliars pic. Could you please post the link? Thanks,

Steve Pierce
02-02-2006, 07:43 AM
I have Clyde Smith's forming tool that I will post pictures of when I get to the shop. I took it to my buddy with the machine shop and am going to have the parts made to build a few of them.


http://sparky.supercub.org/photopost/data/500/medium/100_0137.jpg

behindpropellers
02-02-2006, 08:38 AM
Steve-

Can you post some pics of clydes tool when you get a chance. In the welding class I took they said that welding to zinc plating was not a good idea. Is bead blasting enough to remove the zinc plating on tools to weld to them?

Tim

Steve Pierce
02-02-2006, 09:06 AM
Looks like about $150 worth of parts to build these if anyone is interested. I figure the more I build the cheaper they will be. I have 5 people including myself wanting one. It has sealed ball bearings and works effortlessly to form the channel for the boot cowl and wing root.

http://sparky.supercub.org/photopost/data/500/medium/channel_tool_2.jpg

Clyde also modified a Malco C5 crimper by grinding the end a little to fit in the channel. I made some like Dan but the Malco has 5 crimps and makes a nice crimp. They are less than $20 on eBay or new.

http://sparky.supercub.org/photopost/showphoto.php?photo=8694&cat=500&ppuser=58

Dan2+2
02-02-2006, 10:26 AM
Those 20 dollar pliers look like the bees knees for this. It is not a good idea to weld zinc or galvanized or really probably any coating for health reasons. But heck it only took a few seconds. Is that a good enough excuse? Probably not. Steve the die bender looks really good but in my case I may never build another plane so can't justify needing one. I would like a exp. J3?pa11 though........so maybe?

Longwinglover
02-02-2006, 10:31 AM
Clyde sells pre-formed 3/8 channel for bird cage repair/construction.

www.cubdoctor.com

John Scott

Gordon Misch
02-02-2006, 11:03 AM
Thanks for the pics, Steve! Fluting pliers are in the Aircraft Spruce catalog, pg 529. Looks like the $39 model is exactly like the photo Steve posted. I'm gonna just make one out of an old pair of vice grips. I can see that vice grips would be better than pliars because they'd be repeatable.

Steve, did you angle the rods any, or are they parallel?

cubpilot2
02-02-2006, 12:46 PM
Guess there is more then one way to "skin a cat". The main thing is that you get it skinned.
I was surprised to not see anyone suggest heating the channel for bending. I clamp the end of the channel to a forming template / pattern. Then use a small torch tip and carefully heat the inside of the channel and work your way along the piece while applying a light bending pressure near the end. Apply only enough heat to allow the bending and keep the torch moving. You move slowly, allowing the formed area to cool as you move down the piece. I also use wide jaw vise grip clamps to hold the channel as it can get a bit hot, and helps prevents twisting.