I do, it's especially useful where you have bearings that are a loose fit in the chassis. I would still suggest making up the coupling rods first though to get into the habit and if the bearings are sloppy you may need some packing height wise although you could always shim the footplate to sort out ride height.
Not sure ...... I think you would need to install the long posts so you can pass through both bearings. The way I did it (without a jig), was to bend the chassis, check both side are perpendicular to the chassis top with an Engineers square. Insert the bearings then the wheel axles, the should spin freely if the chassis is square. Remove the axle and bearings insert the frame spacers which will hold the assembly square. Paul
Toto You can use the chassis jig as you described. I too have an Avonside jig, purchased second hand via the well known website. It too has the same marks as yours. I believe these marks are created as the sheet metal components are made from prefinished steel sheet, and the marks are created in the cutting and bending process on cnc machinery. I have built a Class 04 chassis on mine. The axle holes were etched too small for the bushes, and too close to the chassis edge to open up the holes to suit. I solved the problem by replacing the bushes with Premier items that fit in a smaller hole than Slaters. The bushes now had approx 0.5 mm clearance, I soldered the frame up set it up in the jig and soldered all 8 bushes in place. The chassis came out with all 4 axles in the correct plane. The jig is not cheap but I am delighted with mine. John
