1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Slow Monster Rebuild

Discussion in 'Builds & Projects' started by expired road racer, Nov 24, 2016.

  1. I realised that the fact of boring the 30 mm holes at the front made for good fore and aft and lateral location so I decided I needed to infill the tank base at the rear and use the same technique to get the same degree of lateral and fore and aft location. This obviously required two 9mm thick pieces of ply to be cut, glued in place and filled and sanded.
    Unfortunately, when I came to the hole boring at the back, when I marked out the positions for the two locations I must have moved the tank laterally so I bored the holes 6mm off centre so the tank mould sat skewed on the frame rails. Bollox!!
    So I had to fill the bore holes in again, re-sand and re bore the holes. Its an old rule "measure twice - cut once" which I still have trouble assimilating.
     
  2. The tank mould now sits nicely in place with good for and aft location and enough resilience in the mounting to prevent it being damaged by transmission of shock from the frame rails and it is not possible to move the mould on its current mounts far enough to hit any metal part of the frame. I do need a mechanical fixing to attach it to the frame and I think I have sufficient space at the front to use the standard Ducati over centre catch to latch it at the front. The rear mounting is still a bit of a puzzle, an over centre catch would be nice at the back as well but it will involve a cut out in the seat and a projection at the back of the tank just where it would not be comfortable to have one. I had thought of an aircraft type locking pin (a shouldered pin with a key ring attached to a retractable ball bearing in the shaft similar to the principle of a captive socket on a ratchet spanner) but this would require accuracy of manufacture and compression of the vibration mounts to the extent that alignment of the pin would negate the benefit of rubber mounting. A Hoover rubber drive band is looking the most likely candidate at the moment but this will still require a projection at the back of the tank.

    [​IMG]
     
  3. Having finished neither of the jobs I started, tank mounting and seat mounting, I naturally started on another just because it was in the same area, namely an under seat tray. At first I thought it would be nice to show a glistening sheet of polished alloy to all those following lamely in my wake. I had some pristine 2mm aluminium sheet and thought I would attach it to the underside of the frame rails by means of the staggered lugs behind the suspension rocker and the two mounting points for the seat lock. The gap was measured at 160mm between frame rails, a cardboard pattern cut as they taper slightly aft of the rear frame brace and the aluminium jig sawed and filed to shape. It was only then that I realised that the mounting points at front and back are displaced vertically by about 5mm either side of the centre line of the frame rail tube. Measuring the gap between the rails was not good enough the plate would have to be wasted to fit nicely. This did not show up on the cardboard template because it flexed slightly but the aluminium was more unforgiving. My plate fitted exactly for about 2mm in the middle along its 290mm length and only there.
    Having invested about an hour in cutting and filing the plate I was reluctant to bin it and I thought supposing I edged the sheet with rubber moulding I could make it seal against the frame rail. I couldn't find any suitable moulding so thought what about rubber insulation from 2 core flex. I tried stripping it by pulling the inner insulated wires but it just tore along the weakest point resulting in a semi spiral line. I then tried stretching the cable between two g clamps and Stanley knifing the insulation against a straight edge. This worked better but the 2 cores are not consistently in the same relative position within the flex and so the end product was lumpy in appearance when I tried attaching it to the aluminium plate.
     
  4. The solution to the under seat tray is another carbon fibre mould which I made yesterday. Looking at my S4 the under seat tray has an indent about 15mm deep to allow the hugger clearance on full bottoming of the suspension, the M900 has a different suspension arrangement with the hoop and also I have ride height adjusters fitted which would give about 20mm more clearance, I therefore concluded that a flat bottom would be OK.
    Underseat tray mould.JPG
     
  5. You will note I cocked up once again cutting out the mounting locations then realising that I needed them so I had to make infill bits and glue them in.
    I also machine up some aluminium parts to fit the tray and made a bracket to hold the rear most part of the tray
    Under seat tray bracket and machined parts.JPG
     
  6. I only managed one set of the machined parts because the belt broke in the belt drive of my lathe (probably because of the abuse it took finishing the stainless steel peg for the exhaust hanger).
    I was quite pleased with the finish obtained. The washers are quite hard to machine because you have to move the tool in two planes simultaneously to achieve the taper. The compressed cotton reel thingy is designed to fit inside the tray and to have 4mm bungee wound round diagonally opposite reels. This will hopefully stop any tools jumping out of the tray over bumps. The top hat piece is designed to accommodate the captive nut on the underside of the rear frame brace (originally for the seat latch bolted from above). I did not want to tighten the screw from the underside effectively against the strength of the weld so I inserted 6mm x 30mm stainless bolt and wound down a nut onto the top of the frame brace and welded from above. Removing the captive nut below was not really an option as it appears to be projection welded and I could not get an angle grinder into the space where it sits in any case.
     
  7. ictures here are of the seat under tray bracket attached, unfortunately the side view shows the return on the bracket and it looks very obtrusive. I considered turning it around so the returns on the bracket faced upwards but it will not fit that way round as the bolt holes aligning with the seat lock are displaced about 10mm to the left side of the bike. The side of the seat hump will probably hide it from plain view but I know it is there so I think I will have to make a mark 2 bracket.

    View attachment 86812 Under seat tray bracket side view.JPG
     
  8. I also started to think about my parallelogram rear brake hanger. As can be seen from the picture the caliper holder has a crank on it of 10mm.
    I plan to make a floating caliper with 10mm plate and 75mm aluminium bar. I do not think I can bend 10mm plate accurately (twice) so I plan to make the caliper mounting plate flat. I will spacer the disc out by 10mm, probably cutting it from one piece of plate rather than 6 x 10 mm spacers. The caliper itself will be mounted above the wheel spindle and the triangular mounting plate will extend below the wheel spindle where it will be attached to a 8mm spherical bearing and a reaction rod and another 8mm rear caliper mount.JPG spherical bearing to the back of the engine. The 75mm bar starting from the inboard end will be 55mm for 10 mm then 75mm for 10 mm (to provide a mounting face for the 10mm flat plate which will be attached by 5 or 6 countersunk 6mm allen screws) then 55 mm for the remainder of its length. The bar will be bored to take the wheel spindle and machined either side to take 2 x standard rear wheel bearings inserted from either side (interference fit) and seated on a bore hole that provides for 0.5mm projection of the inner race on each side. I think that will work - all I need now is the drive belt to be delivered for my lathe.
     
  9. Spent yesterday thinking about the rear light/indicators/number plate light, attach them to the seat or to the frame?
    For to the seat attachment: ease of mounting, can be kept within the profile of the hump so possibly aesthetically better;
    Against attachment to the seat: I will have to cut a window in the base of the rear hump which will not be easy to make look good, the weight of the lights/fittings will be on unsupported carbon fibre which could lead to cracking/crazing and earthing issues and whenever the seat is taken off the wiring connectors have to be parted. On balance attachment to the frame won.
    I cannot mount the seat until it is made so I had to devise a means of working out exactly where the seat will sit so I can fabricate brackets for the parts.
    The picture what I took will not upload so basically I strapped a 0.5metre length of 10mm tube to the frame rail with duct tape to give the line for the seat base.
     
  10. Where would we be without duct tape?
    I intend to use LED rear lights, indicators and number plate lights and, in order to do away with mirrors altogether, I will mount a rear facing camera with a 4" TV screen in the dash underneath the speedo /rev counter. All the kit came to £21 from Banggood in China, cheaper than a single mirror and almost certainly lighter. Probably it will not be very good at spotting the feds should they decide to follow but that is no change from virtually any Ducati designed mirror anyway.
     
  11. The angle of the seat base at the back permits the mounting of a rear light and number plate LED across the frame just aft of the truncated frame rails from which I will hang the rear number plate bracket. The camera (already in a plastic housing about 25mm deep) will be mounted centrally aft of the number plate/ rear light box on an arrangement that permits a measure of up and down view adjustment. The LED strips for the indicators incorporating a second rear light and brake light will be mounted in an arc that follows the trailing edge of the seat hump (less about 20mm). so first job was to make the rear brake light/number plate enclosure. Using 2mm aluminium plate from my scrapped under seat tray I folded this up.
    rear light enclosure easyweld.JPG
     
  12. The enclosure is 120mm wide x 18mm deep x 30mm high. I intend to cut a window in the lower width to allow the single strip white LED to light the number plate with a similar window in the lid (not shown) for the red LEDs (2 strips) for the rear light.
    I bought the Easy weld rods to weld (solder) the corners using a propane paint stripping torch. They are not as easy to use as shown in the advertising DVD. A propane torch barely has enough heat to get the work piece up to temperature to melt the rod and even when it does when you add more rod it cools the molten pool down so the weld material freezes solid without bonding to the work piece. The first rod disappeared into sold blobs of aluminium without success. I did manage to "weld" one corner and subsequently finish it. I was working with the enclosure held in a vice with the corner uppermost and I think the vice was acting as a massive heat sink. When I try to weld the other three corners I think I will make a wooden frame to hold it and hope that enables the rods to flow better. The weld material, whatever it is made of is much harder than the base aluminium, so I wonder about its ability to survive vibration.
    [​IMG] [​IMG] [​IMG]
     
  13. My first thought about the lid for the enclosure was to cut a piece of 2mm aluminium about 8mm larger then the enclosure and panel beat the 4mm surplus on each edge to fold around the box. I cut a piece of 18mm plywood the size of the box + 4mm on the length and breadth and then tried it. FAIL.
    Possible reasons for fail, lack of skill with a hammer (surely not my mates say it is the only tool I have any real skill with), wooden former too soft and changing shape with each blow, wooden former moving in the vice. Whatever when I took it out of the vice it did not fit so I tried to recover it by stretching the aluminium which resulted in no dimensional change and a lot of dents on the surface.
    rear light enclosure lid fail.JPG
     
  14. Plan B is to cut the aluminium lid as a flat piece exactly the same size as the top surface of the box in 1mm aluminium, cut the window for the rear lights and then cut a piece of 3mm Perspex to just fit inside the box and araldite the two together. The perspex will provide a register for the lid to fit and I will cut a rubber gasket to go round the perspex between the vertical sides of the box and the lid. 2 aluminium spacers drilled and tapped 5mm will be soldered on either side with stainless studs projecting through the number plate bracket and with ss button socket cap screws to hold the lid on. I may need an internal segregation piece of 1mm aluminium to prevent bleeding of red light to the number plate.
     
  15. Not much time in garage this week as SWMBO was off work and half term for sprogs.
    Finished, apart from painting, the rear light / number plate light enclosure, then when I wired it up to check it one of the red LED strips was defective so another £1.98 but annoyingly a two week wait for it to come from China
    number plate rear light enclosure.JPG
     
  16. Thought about the protection for the oil cooler now to be mounted in front of the front cylinder exhaust header and bought some 1mm steel mesh (powder coated black) and spent about half a day making some edging strip from 24swg galvanised steel. I brazed the mitred corners and set fire to the powder coating but not a real problem as I intend to paint it anyway. The difficult bit is how to mount it about 3mm in front of the oil radiator in a way that is vibration resistant and durable enough to protect against ballast coming at it from the front tyre.

    Oil cooler mesh guard surround.JPG Oil cooler mesh guard.JPG
     
  17. Incidentally, a completely revised opinion of the Durafix easyweld aluminium solder. In completing the light box I had two threaded bushes 5mm about 15 mm deep to secure the lid and provide a mounting for the rear fixing studs and I also had a divider piece between the red LEDS and the white LED for the number plate light. When held in between wooden battens in the vice the "welding" was very easy with just a butane blow lamp. In fact it was so easy that all the previously made joints at the corners all re-melted and ran away so had to be done again. I am hoping that I will get proficient with this stuff because the (in my head) putative design for the rear light / brake light /indicators will involve quite a lot of detailed work with this material.
    [​IMG]
     
Do Not Sell My Personal Information