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  #1  
Old 08-22-2017, 03:32 PM
findane findane is offline
 
Join Date: Oct 2014
Location: Naples, FL
Posts: 30
Default Canopy Side bars

I've been struggling with the canopy frame for several days. I have the forward and aft bars within tolerance. My problem is the square side bars are 5/16" away from the longeron profile. I need to spread the side bars at least 1/4". So far brute strength from two old guys hasn't worked. Anyone have a method that works?
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  #2  
Old 08-22-2017, 05:23 PM
John Tierney John Tierney is offline
 
Join Date: Jan 2006
Location: Salem, WI
Posts: 220
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I assume you are talking about a slider canopy. If you are happy with the width of the front hoop, I suggest getting some wood dowels and coring either a 2x4 or a table top to exactly fit the front hoop width prior to torqueing on the square tubes and plugging the dowels into the 2x4 and front hoops to lock down that dimension. I used the base of the finish kit crate as my table and was able to persuade the square side tubes into shape with a well padded conduit bender, using small, incremental force at multiple locations.

Be aware that changes made to the side bars will affect the rear hoops...do what you can to lock down dimensions.
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  #3  
Old 08-22-2017, 07:08 PM
terrye terrye is offline
 
Join Date: Feb 2010
Location: Vancouver, BC, Canada
Posts: 642
Default Canopy side bars (square tubes)

Luckily my canopy frame side square tubes follow the longeron shape very well, but I spent weeks trying to get the front round tube hoop to match the roll bar shape. After trying: bend by hand , bend using ratchet straps, bend using big C-clamp and wood blocks clamped to a workbench , hydraulic pipe bender , I finally built a good hydraulic tool. Used a remote hand pump/reservoir and a small porta-power hydraulic cylinder. Built a rather elaborate T shaped frame from aluminum channel and bolted a block at one end for the porta-power. Made some wood bending shoes for the end of the porta-power and the T cross.

But using some tips from another builder, I traced the shape of the roll bar onto the workbench, then I had a good reference for the shape of the front hoop.

My advice would be:
1. If you're happy with the shape of the front and rear hoops, as another poster advised, lock these shapes in place with a fixture (2x4 or whatever).
2. Transfer the shape of the longerons to a workbench.
3. Mount the canopy frame on the workbench so you can use a hydraulic press of some sort to bend the square tube. These are pretty strong and take a lot of force to bend them.
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  #4  
Old 08-22-2017, 08:26 PM
findane findane is offline
 
Join Date: Oct 2014
Location: Naples, FL
Posts: 30
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I was thinking of trying to use a hydraulic bottle jack to spread the bars. Good advice to transfer the shape of the longerons. I plan to make a wood shoe the same shape of the longeron to bolt to the end of the jack
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  #5  
Old 08-22-2017, 08:43 PM
Kyle Boatright Kyle Boatright is offline
 
Join Date: Aug 2005
Location: Atlanta, GA
Posts: 2,896
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The simplest and most effective technique I found was the easiest I tried. Bending blocks. Look at the bottom right picture on this page for an example.

http://www.blackhillsairsports.com/J...l-jigging.html

All you do is create a fixture to hold one end of the frame tube, then add a fulcrum with a radiused edge to pull against and bend the tube. A little effort goes a long way, and (like fluting ribs) it is best to make a lot of little bends, rather than one big one.

Before I found that solution, I tried pry bars, straps, a come-along, a jack, and every foul word I knew at the time.
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  #6  
Old 08-22-2017, 10:10 PM
terrye terrye is offline
 
Join Date: Feb 2010
Location: Vancouver, BC, Canada
Posts: 642
Default canopy side bars

I used a hydraulic bottle jack to bend my longerons, clamped them back to back and used a wood shoe to gradually bend the shape to my template. The bottle jack works well but only if it is mounted vertically. If this works for you to bend the square side tubes, great. But this is why I ended up building my bending frame using a porta-power. The hydraulic cylinder works in any orientation and the combination reservoir, hand pump and valve is placed remotely. Also keep in mind the tube will spring back considerably so you can't make the wood shoe the same curvature as the longeron.
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  #7  
Old 08-23-2017, 06:52 AM
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bret bret is offline
 
Join Date: Feb 2010
Location: Gardnerville Nv.
Posts: 2,651
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Quote:
Originally Posted by findane View Post
I've been struggling with the canopy frame for several days. I have the forward and aft bars within tolerance. My problem is the square side bars are 5/16" away from the longeron profile. I need to spread the side bars at least 1/4". So far brute strength from two old guys hasn't worked. Anyone have a method that works?
Is this with the canopy and skirt in place? don't forget about the canopy load flexing outward when the plexi is installed.
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  #8  
Old 08-23-2017, 09:23 AM
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airguy airguy is offline
 
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Location: Garden City, Tx
Posts: 3,852
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Quote:
Originally Posted by bret View Post
Is this with the canopy and skirt in place? don't forget about the canopy load flexing outward when the plexi is installed.
With the plexi attached to the frame, you'll get 1/4" to 3/8" spread on the frame due to the plexi pulling it wider.
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  #9  
Old 08-23-2017, 10:25 AM
findane findane is offline
 
Join Date: Oct 2014
Location: Naples, FL
Posts: 30
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Thanks to all for the great suggestions. I think I'll first try a manual hydraulic ram jack with profiled wood shoes. Northern tool has one for $80. If that doesn't do it then I'll have to figure out the bending table.
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  #10  
Old 08-23-2017, 05:45 PM
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bret bret is offline
 
Join Date: Feb 2010
Location: Gardnerville Nv.
Posts: 2,651
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Are you saying the bottom rail does not follow the shape of the fuse? or it is overall too narrow? Mine was good to go out of the box, but I have read here from others, to be carful bending the frame, one bend here and you will need to chase 2 or 3 there......on and on and on....so I've heard
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