Victory mc footboard-round 8-rough finish, fit sleeves

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(in posting this project sequence, I omitted Round 8---which, everybody noticed!.......my bad!)Victory mc footboard-round 8-rough finish, fit sleevesSeptember 2, 2007ROUGH FINISH1-Below are rough-finished mounts. The gnarly top weld overlays and bead fairing, was purposely made higher than the parent surfaces they were on to allow flush finishing without having to go back repeatedly and fill up low points. The more touch up welding done in the vicinity of the casting, the more risk there is, for the castings’ sub-surface porosity to create lettle pin holes.I’ve only got one 1/4” dia. ‘low point’ to fill and re-fair with weld.    There are some porosity holes, in the work at this point. Tomorrow, I’m going to try and deal with them.If one sands into the casting surface much at all, they can expose porosity, as well.    Tuesday, I’ll order some more fine grit flap 2” wheels and cartridge rolls for final finishing. Finishing on parts like these is something, you creep up on.http://www.weldingweb.com/attachment...1&d=1199176756    -4.5” angle grinder-very high points of welds were knocked down with Pearl 60g flex disc-next was light flushing with both 3M coarse, fibre-tex abrasive pad and a Norton Charger, 120g blue, zirconia aluminum, flap disc    -air die grinder used various 2 and 2.5” 60 to 80g flap wheels, small rubber drum sander, sizes of tapered and straight cartridge rolls for the contours and tight radii blending. Using almost no pressure, with fairly high rpm, closely viewing the sanding as it occurs, having lots of patience, really helps.Tip Time: On critical finishing, only use new abrasives. Change the abrasive tool, before it gets loaded with much aluminum—to avoid the embedded aluminum from making big gouges or scratches. Start off on non-show areas or sample pieces, to get an idea of what’s going to happen in the finishing.    If one gets in a hurry, they will suddenly create a huge amount of rework.http://www.weldingweb.com/attachment...1&d=1199176891http://www.weldingweb.com/attachment...1&d=1199176942Above are gusset inside views. These details are non-show, so they remain as-welded. All of the inside and outside joint connections were beveled, for full or close to full penetration welding, then fillet welds overlaid repeatedly.    The strength of these mounts, is still limited by the inherent strength of the casting—which has been increased by the ‘strong back’ gusset plates, added as the first step in fabrication. The 2 socket head cap screws used, fasten into machined, tapped, steel welded bosses in the steel bike frame. There’s a limit to how much ‘gaffe’, the tapped holes in the frame can withstand, as well.    A mount of this nature, really should have 3 mounting holes, not 2-due to the leverage, force and angularity of forces transmitted into the screw mounting.......but that is not possible, without re-design of the bike’s frame. I’ve never liked 2 hole mounts, for a deal like this.     Due to all of the above, this job was undertaken as a ‘Best Effort Repair’.Fit bolt mounts with .375 o.d. SS spacers    Both Rivco and Victory, clearance the lower mtg. hole in their mounts, to .375 i.d.--apparently to allow for misalignment, mis-fiting of parts into the welded, tapped steel barrels in the frame. That’s fine-for stock mounts---a little excessive, maybe—putting all the clearance into one hole and not both of them. 'Normal' practice by experienced engineers, place the same misalignment tolerance in both holes-not one--for some highly practical reasons.[I’m not impressed by Rivco’s engineering expertise—as we went thru the debacle of replacing the footboard clevis pins---since somebody (and an arrogant, ignorant—somebody) at Rivco, decided to take a standard SAE ‘inch’ design clevis pin.... have metric snap ring grooves machined into the pin---creating an almost, not visible groove for the snap ring to seat into----sort of. When my customer queried Rivco eng. about this, they blew him off--’the pins are to specification’......well, they don’t have squat for a safe ring retention, and they’re a mix of metric and inch specifications---which simply isn’t done for a whole bunch of good reasons. Another example of ‘New-Age Engineering’.                          They need to take 2 remedial courses: The first--in handling pertinent, technically-competent, customer inquiries, in a mature, non-provincial manner. The second -a combined study of ‘Geometric Positioning and Tolerancing’, Drawing Interpretation & Design for Form, Fit, and Function....I used to teach that-to machinists, toolmakers, inspectors, engineers and managers.]This extra ‘slop’, in fit of the .375 i.d. Hole to the 8mm (.314) o.d. Mtg. screws, will put additional stress on this lower hole with these extended length mounts. This slop can also cause relative motion, in use.     To alleviate the above, 2 spacers were machined from 304 SS, seamless tubing, .375 o.d. X .312 i.d. X .290-.310 long. (I think and design in ‘inch’, not metric---Old school.) The red circles show the spacers and the lower mounting hole they are to go in, for assembly into bike frame.Note to customer:When the screws with new, hardened, sized washers are installed-or removed into the bike frame it will be important to make sure these sleeves are in place and don’t get lost. The sleeve height (or length) is less than the casting boss thickness, so the screw is not tightening on the sleeve. I’m including a length of this special, SS tubing, with your spare parts, if you ever need more sleeves made up. The sleeves are a sliding fit, into the casting bosses. After powdercoating, they may be snugger.http://www.weldingweb.com/attachment...1&d=1199177174continued in Round 9 Attached ImagesBlackbird