Making the Stays
Tom Porter's Recumbent Bike Plans 2005/2006
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New Plans 2005 Frame Build 2005/2006    
Dual 700C Z-Frame Build 2005/2006 -       Tubes    Frame    Dropouts    Stays    Final
Making the Stays
These are .875 x .035 tubes, which I wouldn’t recommend for the heavier rider; but had laying around so what the …

I bent these in an EMT bender chucked into my bench vise using a long length of thick wall 4130 for extra leverage, as this stuff is difficult to bend. It is IMPERATIVE to work slowly and with great care to get a decent looking bend, this takes some practice so don’t hurry it. If you are not careful you will wrinkle or collapse the thin wall.
 

The stays now have been ovalized using the wooden blocks to fit over the .875 x .065 tube in the main frame. If you look closely the one on the left has some wrinkles in it; I haven’t done this in a while and had to rediscover the “touch”. The stay on the right looks good though. 
Here I have applied layout dye for marking the dropout cutouts in the stays. If you look closely you will see a small piece of metal taped to the square. When both are laid out properly on a surface I marked for the ˝ point on the tube. 
The ˝ mark was used to layout a template that I made and then taped to the tube and finished scribing dropout cutout. 
Now the tube is secured vertically in a bench vise and two start notches are made in the tube. 
Next the first cut is made with the hacksaw through both wall of the tube for the perpendicular fit of the dropout.
After the first cut material is removed the parallel lines are made with two cuts with the hacksaw angled to the rear of the stays. 
Remove material between lines and finish with files to match the profile of the dropout. I agree this is too much work, so I have some better ideas about this on the next frame build.
The dropout is now tack brazed to stay, this shows the reasoning with using this method; all that is done is a spring clamp holds the dropout in place while it’s tacked.  
Next is to complete all joins of dropout to rear stay. 
The rear stays/dropouts are finished with a gusset plate to seal the end and reinforce the joint and a .875 hole saw in the miter jig for the tubes to slide over the frame tube. 
Now the frame is mounted in wooden jig to proper ride height so that the rear stays can be fitted. The rear stays are fitted to the cross tube and the rear wheel clamped into the dropouts. The tape measure is used to make sure both sides of the axles are equidistant from the bottom bracket shell, and the level is placed against the rim to make sure every reference between the bottom bracket and dropouts are perpendicular to the surface. Take some time and check carefully more than once. If anything is off make necessary adjustments before proceeding. 
Now that we’ve taken our time to get everything aligned its time to tack the stays in place. 
The frame is removed from table jig and partially assembled to check for chain clearance. Everything looks good to go here. 
The frame is placed in workstand to finish brazing. The threaded rod is set at 135mm, this IS necessary, as the stays will draw together when either the ends are brazed or a bridge is mounted. If this is not done it will close in about 5 mm, that is why the rod is set at 135mm to get 130mm over locknut spacing. 
The basic frame has been assembled with the necessary components and a new pulley with a double channel has been fabricated. The chair just shows roughly what the ride height of the completed bike will be. 
Next - Adding derailleur tube and braze-ons  

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