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Discussion Starter #21 (Edited)
Prior to powder coating there was quite a bit of repair work to do to the the frame. First the frame and other bits including tank were sent away fro sand blasting to remove the worst of the old paint. The sidestand support was broken off, so that required the old remnants to be removed using an oxy-acetylene torch to melt the old brazing. A replacement lug was procured and mig welded on. I hope I got the angle right, or I will be doing some more cutting!
The main stand support had been badly welded by someone else, so that was cut away and all the old welding ground out of the way, then re-mig welded in place. There were quite a few dents in some of the down tubes, there were brazed up and carefully ground and filed down, till the original contour was achieved. Every time I looked there was another dent to fill! Its not the sort of thing you want to discover after powder coat.
The center stand had road wear marks on it, so that was built up with brazing. The swing-arm had chain wear marks also brazed up. The chain-guard had had a horrible repair history, and the best i could do was cut away the offending section and fabricate it.
The tank mounting bracket had to be cut away and a new on fabricated.
The center stand holes were a bit elongated, so i brazed them up and re-drilled them for a snug fit.
The end result all in black is well worth it, especially when a friend Brett organised the powder coating for free!
 

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Discussion Starter #26 (Edited)
After the sand blasting, the petrol tank looked more like a sieve with dents in it! Very disappointing, as I really did not want to spring for a new one. So I decided to do major open heart surgery as I needed to remove as much rust as possible and mechanically seal the worst of the holes before sealing, not to mention getting the dents out so i did not need to use lots of body filler.. Using a grinding wheel in the small angle grinder..( OK first off I satisfied myself there were no remnants of petrol in the tank whatsoever, even trapped in the seams....If not you have to thoroughly rid the tank of petrol fumes and create an inert atmosphere, like drenching it in water, or filling with CO2 gas. This can be very dangerous if you don't know what you are doing) I ground the welding off all the seams, and with a little persuasion the tank parted in to its 3 component parts. Here are some picture detail of progress.. don't worry there is good news...
 

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Discussion Starter #27 (Edited)
I then sand blasted the insides to remove all the rust, then had to soak in hydrochloric acid for a bot to deal with the deep pits. Then started the job of soldering up all the pinholes. For this I used self fluxing silver solder rods. I fixed the oxyacetylene torch to the bench, then would hold the tank segment to the light looking for a hole, then bring the tank down on the flame, from the outside, whilst feeding in the silver solder from the opposite side. The pit holes were filled up one dab at a time, until I could see no more holes when held up to the light. The next step was to do a final vapor blast to remove all the flux residue, and prepare the interior of the tank for a later coating stage. Next step was to remove the many dents in the tank. this is an easy process when the tank is open. I first dragged a body file over the dent area to highlight where it was, then selected the lowest point, then from the underside, with the tank resting on a block of wood, I delivered varying intensity blows with a small ball peen hammer. Only 2-3 taps, then re-apply the body file, this process continues until the body file picks up no more dents. it is very satisfying to deal with dents in this way! There were a few larger holes that I had to cut out metal patches and silver solder these in place from the inside. Next all the seams were straightened out for a good fit. Next step was to MIG weld all the seams together. A low intensity setting and very short bead lengths worked. There were the inevitable blow through's which had to be carefully built up. At the end all the excess was ground off and touched up where appropriate. I did check fit the chrome strips form time to time and made the necessarily adjustment.
 

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Discussion Starter #28
The next tank process was to further seal the tank, I wanted a good mechanical seal, ahead of applying a layer of epoxy sealer. I installed the taps, and the filler cap, but first put a layer of plastic under the cap, and wrapped the cap in duct tape, so the new chrome did not get spoilt. Then I attached a small air regulator to the fuel tap, and connected to the shop air supply. Dialed in a bit of air, and then started to tackle the larger leaks just be feeling for the air stream. Here i used silver solder, as the MIG welding just tended to continue making leaks. Once the obvious leaks were identified, I placed the tank in a large drum of water to identify the remaining smaller leaks. Here I marked them up with a wax crayon, and would repair up to 3 at a time, retesting. it is a very frustrating exercise with seemingly no end in sight. Eventually the leaks were all closed. The outside of the tank was again acid etched to remove the surface rust, the inside in the mean time had been kept dry. I then procured some recommended epoxy tank sealer. it is stuff called Prostruct 632 manufactured by Stonecore Africa http://www.stoncor.co.za. It is originality intended for the industrial coating of concrete tanks, but has been widely used to seal up steel and glass fiber petrol tanks.
First the tank was flushed out with paint thinners and air blowed dry, then the tap holes were plugged with the same thread BSP end plugs. The epoxy was mixed to specification and poured in to the tank, then slowly rotated by hand for at least an hour to evenly coat the inside surface, the excess was then drained from the filler cap, which incedently had a piece of plastic sandwiched between the filler and the cap. Then the tank was stood on its nose, until the epoxy had set. The end result is a very durable coating.
 

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Discussion Starter #30
The next job was de-chroming - I needed to effect repairs to the mufflers and rims, and get the mudguards back to bare metal as they are supposed to be painted and not chromed. I took a stab at dong some of my own electro de-chroming with a large tank, some dilute hydrochloric acid and a current, but this just made matters worse, by trashing the headlamp shell. So I thought it bet to let the professionals do it. The lot was sent of to the electroplates and a few weeks later the stripped bare items were available. For the items like rims and muffler's, I set about brazing up all the dents, then grinding, filing and sanding till perfectly smooth. The one muffler had quite a bad dent in it, so I cut out a flap around the dent, bashed it in to shape, and welded it back in to position. I also had to replace the support brackets on the mufflers with new fabricated ones, complete with stamped in part number! The mufflers I have don't seem to come from this vintage of triumph, so will have to invest in the correct ones at some point in time. The header pipes were also subjected to the same treatment, where several dents had to be filled in. The items to be re-chromed were then sent back to the electroplaters. The carburetors were also chromed and this had started to pit. I had them de-plated, but the pitting damage was to great, and there were actually holes in the float bowls.I elected to finding a good used set on eBay.
 

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Discussion Starter #31 (Edited)
Question:
1) Does anybody have a good picture of the 71 Oil Dip Stick and or dimensions, as I cant find the original, and the more modern ones that are attached to the cap, wont fit in the hole due the the hanger bracket being in the way. I really don't want to chop that bracket out of there, and I need the oil dip stick to function in terms of reading levels etc.
2) What is the accepted practice for coating polished aluminium ? I tried a twin pack clear automotive pain, but just sitting on the bench within a month it had started to tarnish right through the clear coating! I assume the coating had microscopic crack's or was a bit acidic. I am talking about coating fork sliders and side covers etc. I have had to remove the old clear coat by soaking in thinners and brushing it all off, then re-polishing.
3) Does anyone know what the conical hubs and brake backing plates had as a finish in the 71 model year. I heard it might be grey/silver paint, 72 seems like it was polished. Right now i have just left the vapor blasting finish on them.
 

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Discussion Starter #32 (Edited)
Crankshaft / Connection Rods
After vapor blasting the crankshaft clean, and discovering it was work outside of specification, I ordered a set of undersized main bearing shells. The next step was to remove the crank filter plug. First the bolt that retains the internal filter was removed. Then the are where the plug had been secured with a center punch was drilled back a bit. I then tried in vein to loosen the plug with a 1/2" socked flat screwdriver. Next i drilled out the slot in the plug with a 3mm drill bit. Basically a series of holes going right through the plug, and hammered the screwdriver bit in to the new slot. With a lot of force and some heat (To break any old locktight) it came out, but the plug had to be sacrificed. I have now bought a HEX type for the re-install so at least there is a better chance for the next time. The strainer was full with a carbon like substance, it became very clear why changing oil regularly might be very beneficial, and it also explain why this engine was so worm out! O then prized out as much of the crud as possible with a long screwdriver, a realy messy process. The next step was to remove the strainer. To do this, i used an M16 Tap to tap a few threads in to the inside of the strainer, then inserted an M16 bolt and nut. The nut is run up the bolt, then the bolt is tightened in to the strainer, then the nut is wound down till it touches the side of the crank, then the strainer is literary jacked out using the nut and a spanner. make sure the retaining bolt is out of the way first. I thought I might battle but this method sure works well! The hole and strainer were cleaned well and the crank sent off for grinding with the con rods and bearing shells.
The con rods were rather nicked in places which is not good as each nick and scratch can form a stress raiser leading to later con rod failure, something which is VERY expensive. I first sanded the con rods with varying degrees of grit sand paper until all the nicks were out and the surface smooth. Then I did a round of vapor blast just to check the surface texture was even. The next step was to load up steel shot in to the sand blaster and shot peen the surface, under low air pressure. This has the effect of evening out the surface tension of the metal, then lastly the parts were again vapor blasted, leaving a nice satin finish. I had also ordered in a new set of connecting rod bolts and nuts as well as small end pushes. The old bushed were driven out using different size sockets in the vice with suitable jaw protector's and well as the application of heat to the small end, to expand the aluminium. The new bushes were drawn in using a threaded rod and some suitable spacers, then the oil holes were drilled to match those in the small end. The next step was to use an adjustable reamer, and slowly work the hole size up, until the gudgeon pin was a tight sliding fit.
My next steps are to assemble the oil strainer, and then check the static balance of the crankshaft.
I have resolved to fit a paper element oil filter to the bike to help stave off this sort of debris buildup in the crank in the future.
Cleaning out he oil strainer and oil gallery on the crank has got to be on of the most important tasks to be done when stripping an engine. I shudder to think of this crud coming loose after a rebuild or even hampering oil flow!!
the closeup shots of the connecting rod, show the surface finish after shot peening, and then again after vapor blasting, the first shot shows old vs sanded.
 

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Have you tried a Google Search for any of these answers? I have found by typing in different work strings often times you can come up with 99% of the answers you are looking for and try Google Images for pictures too.

Question:
1) Does anybody have a good picture of the 71 Oil Dip Stick and or dimensions, as I cant find the original, and the more modern ones that are attached to the cap, wont fit in the hole due the the hanger bracket being in the way. I really don't want to chop that bracket out of there, and I need the oil dip stick to function in terms of reading levels etc.
2) What is the accepted practice for coating polished aluminium ? I tried a twin pack clear automotive pain, but just sitting on the bench within a month it had started to tarnish right through the clear coating! I assume the coating had microscopic crack's or was a bit acidic. I am talking about coating fork sliders and side covers etc. I have had to remove the old clear coat by soaking in thinners and brushing it all off, then re-polishing.
3) Does anyone know what the conical hubs and brake backing plates had as a finish in the 71 model year. I heard it might be grey/silver paint, 72 seems like it was polished. Right now i have just left the vapor blasting finish on them.
 

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Question:
1) Does anybody have a good picture of the 71 Oil Dip Stick and or dimensions, as I cant find the original, and the more modern ones that are attached to the cap, wont fit in the hole due the the hanger bracket being in the way. I really don't want to chop that bracket out of there, and I need the oil dip stick to function in terms of reading levels etc.
2) What is the accepted practice for coating polished aluminium ? I tried a twin pack clear automotive pain, but just sitting on the bench within a month it had started to tarnish right through the clear coating! I assume the coating had microscopic crack's or was a bit acidic. I am talking about coating fork sliders and side covers etc. I have had to remove the old clear coat by soaking in thinners and brushing it all off, then re-polishing.
3) Does anyone know what the conical hubs and brake backing plates had as a finish in the 71 model year. I heard it might be grey/silver paint, 72 seems like it was polished. Right now i have just left the vapor blasting finish on them.

let me go through a couple boxes... I have a couple dipsticks (and I am not even talking about the one working in my shop, but you are welcome to that one...LOL)

Polished alum is a pain. You just have to keep up on the polishing, if you want that shine

YES..hubs were painted silver in 71 (at least they were on the TR6 models). My front backing plate was polished, and my rear has been chromed. I think my rear one was changed
 

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Discussion Starter #35
Thanks Lee and Chuck

Here is a more detailed pick of my current hub finish level, which I am inclined to leave it at. You can also clearly see the blemishes that have appeared in the polished aluminium.
 

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Anytime Roger. I have found search engines to be my best friend at times. You might have to do some long drawn out searching but in doing so you gain a ton of other knowledge along the line. :)
 

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Discussion Starter #39
Thanks Dave,
1) Does anyone have the overall dimensions of the dip stick ?
2) Am I correct in assuming it has no markings ?
 

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72 tool kit

This is my original 72 tool kit. I didn't find the double-ended screwdriver which is a real piece of crap and a sure way to strip cheese head screws (Posi-driv in the US) or even the handlebar switch screws. I use the double box-end (ring spanner) to adjust my valves and tighten cylinder base nuts. Bob
 
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