Fitting of Springs to Frame (Tandem)

Eye & Slipper as per diagram:

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Tandem Rocker Roller Springs as per diagram:

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Find correct position for center hanger.
The general rule of thumb is 1" every 2'
(25mm every 600mm) behind center of trailer frame (not including drawbar length).
Trailers with more weight to rear will require axle further to rear (e.g. boat trailers/horse floats).
When welding hangers to frame, weld along hanger with frame, not across.
(welding along frame is stronger)

1. Find correct center position for middle hanger

2. Measure from center of drawbar
(which should be already fitted)
to middle hanger on both sides.
Equal distance ensures hanger are square to drawbar.

3. Measure distance forward and
rear of center hangers to suit
Eye/Slipper or Eye/Eye configuration springs.
Set up according to diagrams and weld hangers into position.

4. Fit axle location pads to springs.

5. Remove front spring to fit braked axle,
refit springs and centralize axle.
(NOTE- lazy axle is approx. 12mm shorter than braked axle when centralizing)

6. Fit U-bolt and fish plates to braked and lazy axles.

7. Check square to drawbar on braked axle.
Tack weld location pads to axle.
Tighten U-bolts.
Measure distance from braked axle
(which is now square to frame)
to rear lazy axle.
When distances are the same lazy axle is now square.
Tack weld location pads to axle and tighten U bolts.
Springs and axles are now assembled to frame.

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