OT question on metal forming

[monte55]

I have an old chaise lounge piece of outside patio furniture. It is made of round formed aluminum tubing and has plastic strap webbing attatched for the body to rest against. My question: The aluminum is 7/8" OD and .070" wall, .740" ID. OK...
The 90 degree bends seem to be mandrel bent from the reduced diameter at the bend but to my surprise........inside the aluminum tube(not all) is a steel 1/2 " x
.050" tube inside which is a very sloppy fit. What is this about? Would it be to help the aluminum to not collapse but like I said it's looks mandrel bent. I am tearing it apart because I need the tube for my heli project. We don't use it and it's been in my junk pile for years. No.........I don't use present deck furniture for my projects.

[fjk]

To keep the corners from unbending and wracking?

Just a guess. I have no real knowledge....

Frank

[etonline]

Is there a joint there?

I see this in boat bimini tops where the alum. sections join. I always assumed it was for the purchase of the screws holding the sections together.

[redintn]

I was asked to fix some of the chairs, not yours. LOL
Had the steel in it as well, only thing I could figure was for strength.

[FusionKing]

If the diameter was reduced then it would look as if it was NOT mandrel bent.
Mandrel bending is used to keep the diameter consistent.
The steel was more than likely used as a cheap way to keep the material from kinking while bending on their bender.
I would think twice about using unknown imported used material on even the most unimportant projects... unless it was to repair/beef-up other lawn chairs which are nortoriously known for being junk.

[FATFAB]

FK is correct the reduced section diameter is indication of non mandrel forming.

If the material is in good condition free from corrosion use it.

[monte55]

The reduced diameter is only on the inside of the bend. There are no wrinkles
on the inside of the 90 degree bend. The outside of the bend is smooth with the tube. I would think the tube would have ovaled if not in a mandrel. It's not. The wierd thing is, as many 90 degree bends as it has, the steel round metal was only in one piece. It fits so sloppy I can't see how it would help much. Another wierd thing is that some of the aluminum tubing has what looks like a welded seam inside like some steel but then again, some is totally smooth inside. The wall of the aluminum is .065 and I wouldn't think it would
kink if bent properly. ....maybe the foreman was walking by and saw the steel tube on the floor and told the worker to clean up his area so he shoved it inside the aluminum tube.

[Bert]

I have an old chaise lounge piece of Wally World cr@p outside patio furniture that we bought 20 years ago. It is made of round formed aluminum tubing that is oxidized 1/2 way through and has plastic strap webbing attatched for the body to rest against (although the webbing is pretty much desinegrated through the years....)

You're using THAT on your helicopter project??!!!!

Well Monte, it's been AWSOME knowing you... I'll think of something to put on your headstone....

[monte55]

What!!............you've never heard of a chaise lounge on a heli? Hey...I'm laying back and gettin down with my bad self. You have a problem widdat?
Uh huh..oh yeah..ain't it funky now.

[monte55]

Hey Bert...........I just got my $900 upgrade 3D program(don't know how'll I pay for it).....send me a pic or whatever of your metalworks Logo and I'll see what I can come up with.......Nick