Design Guide Lines, Basic Rules
- To get maximum strength, use full lengths of tubing rather than piecing tubes together with joints.
- Use the QC-11 fittings to sister tubes together for higher rigidity.
- Use two of the QC-7 fittings with a short length of tube to diagonally brace a 90° (see drawing) tube and fitting combination.
- For structural integrity Make sure that the tubes are fully inserted in the fittings and are properly torqued to 8.85 ft lbs (12 nm).
- When using QJ 12 steel tube do not exceed 48” (1219mm) outside dimension without additional vertical support. However, higher loads may require additional vertical support.
- When towing carts or for extra strength use a self tapping, hex head washer screw – QSHS, through the prepunched hole on the fitting body to fasten the fitting to the tube.
- Preassemble QC-2s with a couple of threads then insert vertical tubes, then two horizontal tubes.
- Use spring clamps to position fittings and tubes prior to tightening.
Tube and Roller Track Cutting Formulas
To calculate the cut length for outer and inner tube dimensions follow these guidelines.
| Conversions | |
| 1 meter | 39.37” |
| 3 meters | 118.11” |
| 1 foot | .305 meters |
| 1 inch | 25.4 mm |
Cutting Formulas
Tubing – Inside Dimension subtract 1.75” (44mm)
Outside Dimension Subtract 3.875” (98mm) from OAL. For a diagonal tube brace using QC-7’s subtract 6.5” (165mm) from outside overall length 4.5” 114mm) inside length.
Roller Track Cut Length – 2.25” OAL of track
5” Caster – subtract 6.25” (158.75mm) from overall height of rack
3” Stem Caster – subtract 4.25” (108mm) from overall height of rack
Tools for Fabrication and Assembly
Fabrication
- Safety glasses
- Commercial grade tube cutter for fast cut
- Hack saw with metal blade
- Horizontal band saw for larger projects.
- Tap measure.
- Pencil or marker
- Flat file to debur any cuts on roller track channel
- Rat tail file
Assembly
- 5mm ball point hex driver
- 5 mm ball point hex driver bit, to use with cordless drill
- Industrial grade cordless drill with variable clutch
- 12” torpedo level with built in magnet
- Carpenters apron for holding socket head cap screws and hex nuts
- 6” spring clamp, these function as third hands to hold fittings together before fastening
- Lengths of aluminum angle. Can be cut and used as gauges for fitting of placement, eliminating these multiple measurements.
