Eelco's Darmah

I was initial excited when a guy at the local metal-sprayers told me that they were molybdenum-spraying a load of selectors for a customer. The boss, however, didn't want to help, as he thought it would be too fiddly to slip mine in at the end. Some people have no romance in their soul! I should hang about on a Friday in the local pub and bribe someone to do a guvvy job for me. So long as i don't wear a tracksuit and smoke a cigar I should be ok.
 
Derek said:
Interesting stuff Lindsay, but how long will it last immersed in hot oil?
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From our 'Principal Technologist' no less!

"It should be OK but if you can get it hot before putting in the oil it would be better. Use a heat gun after it has dried"

Or maybe a wee bake in the oven?
 
I can see some useful applications for a baked-on coatingof it, but it is very thin and so won't make up for the existing wear. I'd imagine that it would help improve the quality of the shift and many other sliding parts in a motor. Thanks
Martin
 
Pronounced with a silent 'sh'

I checked out the coating stuff on ebay and bought an aerosol can of it for £6 (it's slightly out of date, but....) Otherwise its about £80 a litre.
I'm going to ask MMT to vapour blast the forks to get a key and bake it on as recommended. It can't harm (famous last words)
 
Finally got to show MMT the forks today. He said that the 'wear' that concerned me was original machining marks but that there was some 'real' wear but no blueing, as Deputydawg noted. He's going to blast them in ten days or so when I return from working away. I want to coat them as soon as I can after blasting to prevent rust and then crack on with closing the cases. I'll have a look at the tech info to see how much to bake the paint and for how long before firing up the oven again (when the Contented Older Woman is out shopping)
 
I checked out the whole range as I was looking for instructions and found this:
Molykote® 7409
l Description – Heat-curing dry lubricant.
l Applications – Sliding contacts of metal/metal combinations with slow to moderate fast
movements and moderate to high loads; Suitable for oscillating movements or intermittent
operations. For improving the running-in process, for permanent lubrication at high temperatures
and also where oils and greases cannot be used; Used successfully for piston rings and tappets of
combustion engines, magnetic armatures of vehicle starter motors, parts of vehicle brakes, locks,
hinges and pumps, Corrosion protector for hydraulic and pneumatic parts.
l Features – Outstanding lubrication, coupled with good corrosion protection properties;
Resistant to oil, grease, solvents and many other chemicals; Avoidance of fretting corrosion.
l Composition – Solid lubricants; Organic binder; Solvents.
l Temperature Range – From -70 to +380°C
l Packages – Can: 500g; Pails: 5kg, 25kg

Sounds fab but I'll bet it's a lot for half a kilo!
 
Dear pict, Since I can't find any relevant information and am working away again next week, could you please ask your principal technologist for some application advice/ Since it is in an aerosol I guess that I'll warm that up and shake it a lot, first, but should I warm the (vapour-blasted) forks up in the oven before application or just bake them after? What sort of times and temperatures are we talking (I have to arrange for the resident domestic goddess to be out) I do have a heat gun but feel that that may not be so even or controllable.
 
if you are still going ahead with your oil filtration mod i recently came across this (its in german) but maybe of some assistance.

http://home.arcor.de/berndz2001/ducati/oelumbau.pdf

regarding your "crack" are you sure it is a crack and not a casting mould witness, if it is a crack i've got exactly the same, does it extend across the bearing opening to the cylinder mouth ?
 
Hi Martin - Sorry, I missed above. I'll see what I can find out. We just use the aerosol cold so there might not be a definitive answer as to times and temps. We do also use a 'baked on moly' process but I think that uses a completely different potion. I'll find out, but I think the implication was that air drying of the aerosol would do the job and heat gun was belt and braces. And he would have said heat gun as he doesn't realise what we get up to when our wives are out and that the oven was an option! Let you know tomorrow.
 
OK here goes... He stressed that once the component has been sprayed it needs to 'flash off' (tech speak for 'dry' I think) at room temp before going near the oven. Then preheat the oven to 200C. The component temperature need to be 200C for 15 mins so once I explained what it is and there would not (relatively) be a lot of thermal mass then he reckoned total cooking time of 30 mins will be fine (15mins to get to 200C, 15mins at 200C) though a little less might be OK. Did say to put it in at temperature i.e. don't ramp it up or anything. Get the oven to 200C then go. Good luck!
 
MartinW said:
7 of the studs came out easily with my new stud-extractor, although it chewed-up the surface a bit, so some filing-back and polishing is in order. the other, however, needed large applications of heat and freezer-spray (not at the same time) to break the seal and eventually came loose.
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Are these studs the barrel/head ones? Anyway what extractor were you using?
 
Haven't started yet, just sorted the carbs out. All the screws etc were stuck as a stuck thing could get stuck on a bad day for stickinesssssss
 
It was the barrel/head studs and I used an old fashioned teeth over-roller device and a big breaker-bar. i'll post you the device if you want to try it.
 
MMT brought the vapour-blasted selectors round very lovely they looked indeed. He had wrapped them in paper and then inserted them in a plastic bag without ever having touched them. I bent up a frame from a piece of wire to suspend the bits and then sat them on top of my wood-burner for five minutes, during which I shook the can - vigorously, as they always say. A light coat of Moly was followed by five minutes on the stove and then a second, heavier and more even coat. Whilst my Ham joint for tomorrow's tea was finishing, I sat the frame back on top of the stove. Once the joint was out and breathing hamminess all over the kitchen, I stuck the frame in the oven at just below 200. After 15 minutes i switched the oven off and am letting it cool down slowly.
Fingers crossed!
 
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