Before the final welding we used a string line and tacked all components into line on a flat floor. The slats are aluminum to keep the weight down and are usually used around pool areas and such and available anywhere.
The gate has been operating fine for 5 years with a remote operated Aleko AC1400 Electric Sliding Gate Opener. Last summer the lower poly wheels started coming apart so I machined some new wheels out of a 6" stick of 7075 aluminum shown in step 3.
Step 1: Getting the Gate Squared Up and Assembly
Step 2: Hanging the Gate Onto the Mount.
Step 3: Replacement of the Damaged Poly Wheels After 5 Years Use
The improvement in load for the gate operator was dramatic. Now it seems to run faster and much easier with the hard wheels. The 7075 aluminum has a a strength comparable to many steels, good fatigue strength and average machinability, it also has less resistance to corrosion than many other Al alloys. The downside is cost but scrap ends in all sizes are available on E-Bay for much less than new.