Clarke 7 inch Metal Bandsaw

  1. Hopefuldave Intergalactic pot-mender

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    Location:
    The Shed of Danger, surrey, England
    https://en.wikipedia.org/wiki/Phosgene#Inadvertent_generation - chlorinated solvents including DCM... It's one of the hazards the lab' I work in stresses to the folks who work with UV lasers (big 'uns) and might be tempted to use chlorinated solvents. Dunno about the UK, but a few welders in the USA die every year or have "life changing" injuries from using the wrong (chlorinated) solvents to clean workpieces :(

    It's also one of the nasties used to make isocyanates and polyurethanes...

    Disposal... a nightmare, most seems to be "vented to the atmosphere"! Old Nitromors cans advised allowing the vapours to disperse then wrapping the waste in newspaper and binning it, not sure that's legal now we've all turned green to the core?

    Dave H. (the other one)
     
  2. Screwdriver

    Screwdriver Member

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    6,476
    UK London
    Yes I can see the words "Phosgene" and "chlorinated solvents including DCM" but they are not in the same sentence. You can't make Phosgene gas from DCM. Period.

    Bizarrely I am fully aware of the problems with, say, older brake fluids which contained Tetrachloroethylene. Heat them up and you get Phosgene, I even posted that on this very forum some time ago. But just because something has chlorine/chlorates/chlorinated/chloride doesn't mean they are dangerous. If they are you better stick to vinegar on your chips and nothing else. Unless of course acetic acid is also on the danger list...
     
  3. Hopefuldave Intergalactic pot-mender

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    1,692
    Location:
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  4. slim_boy_fat

    slim_boy_fat Forum Supporter

    I remember my Mother cleaning in the bathroom, must have been about 60 years ago. She was using the old staples of Vim and bleach. She must have mixed them during application and was overcome by fumes of some kind, barely making it out of the room.

    Could this mixing have produced DCM or related fumes? :dontknow:. I know she got a helluva fright.
     
  5. Screwdriver

    Screwdriver Member

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    6,476
    UK London
    Interesting. It certainly doesn't make that much of it, not like in the good old days welding next to tetrachloroethylene but I take your point. This more specific article https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3560185/ goes deeper into the possible production mechanism but I am no chemist. I just want to know if there is a known danger to DCM besides breathing the stuff in. I rather suspect if you have enough DCM present to form significant amounts of phosgene, you're already in trouble.

    I will however put it on my list of things not to weld after being stripped.
     
  6. Screwdriver

    Screwdriver Member

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    6,476
    UK London
    Probably chlorine. I am pretty sure you can make it by using washing up liquid mixed with washing powder. It don't half stink but cleans your hands brilliantly. I use it all the time.
     
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  7. slim_boy_fat

    slim_boy_fat Forum Supporter

    That's the stuff they clear patrons from swimming pools if there's a leak, yes?
     
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  8. Hopefuldave Intergalactic pot-mender

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    1,692
    Location:
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    And Tommies from trenches, but that was deliberate...

    Dave H. (the other one)
     
  9. Screwdriver

    Screwdriver Member

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    6,476
    UK London
    One of the culprits, a nasty old siezed guide bearing on a hardened forged eccentric stub. Not something you want to break.

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    Gave the parts a quick wash in paraffin.

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    Some of the bearings really didn't want to come out. Flypress persuaded them otherwise.

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    Nice thing about a flypress is you can use it like an arbor press and give it some torque rather than just hammer it. They came out with a satisfying bang nonetheless.

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    Bearings are 608zz which sounds like they should be super easy to find. In fact I'll go check my bike spares and I may even have some.

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    Pretty sure they're standard skateboard wheelbearings. Should be cheap as chips.
     
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  10. Windy Miller Semi-Professional Potterer!

    Messages:
    2,908
    Location:
    North Kent, UK
    There are some real nasty skateboard bearings out there, so beware!
    Especially on fleaBay..
     
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  11. Screwdriver

    Screwdriver Member

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    6,476
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    LOL. Yeah, I just noticed. You have to wonder why, if they are made in Switzerland, how did they end up in China...

    I may bite the bullet and buy genuine SKF/NSK etc.

    Am currently turning the house, garages, shed, workshop upside down looking for my big box of bearings!
     
  12. KemppiFrog Member

    Messages:
    3,317
    Location:
    Aquitaine
    Some of the nasty bits became apparent when TCT was used as a cleaning agent. The girls who worked with the vats oftened smoked. Drawing CTC fumes through a cig produced phosgene, not very good for ones life expectancy.. Coff Coff..
    I remember 'Dab-it-off, a drycleaning stain remover. CTC, smelt quite nice.. We also used to use it for cleaning the brushes on the genset at the airfield in Norfolk, but were well aware of it's nasty side effects back in the early 70s.

    BTW, sterling work on the rebuild, looks a solid bit of kit, worth the effort. I might try and follow your example:ashamed:
    KF
     
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  13. slim_boy_fat

    slim_boy_fat Forum Supporter

    Now there's a brand name from the past. :thumbup:

    I remember asking someone to collect a big bottle of CTC I wanted to clean a clutch plate which had become soaked in oil due to a leaking crankshaft bearing. Apparently the chemist told him it was very dangerous stuff. Frightened him so much he drove for 15 miles at 20mph to get back with it in the boot.
     
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  14. KemppiFrog Member

    Messages:
    3,317
    Location:
    Aquitaine
    That takes me back:laughing: When I worked (briefly) for a crop dusting outfit, we used to get two 50gal drums of Avgas in the back of a Minivan and drive off into the wilds of Scotland...Not only exceeded the load, but 'slightly' explosive. Also drove with three up front, bit tight, so the middle guy had the gears and the clutch pedal, while the right guy steered and had the brakes. Suprisingly how quickly one could get the co-ordination right. Ah! Those were the days, you young lads don't...... (fill in this space:D)

    Bit later, local bloke had a drum of acetone in the back of a Minivan, missed the sudden corner after a humpback bridge. Wasn't much to scrape up.
     
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  15. Ashley Burton

    Ashley Burton Member

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    4,471
    Location:
    Northamptonhire
    Looking forward to seeing this finished
     
  16. Screwdriver

    Screwdriver Member

    Messages:
    6,476
    UK London
    LOL, yeah, you and me both!

    Lots of fiddly stuff. Cleaned, wire wheel, washed in acetone.

    [​IMG]

    I considered masking off some of the machined surfaces but I think they were painted on the original so I just covered them in satin black.

    [​IMG]

    ...and leave them hanging up to dry.

    [​IMG]

    Got my cheapo bearings on order and knowing I can't finish this off before they turn up (mid week?) has really dampened my enthusiasm for the job. Where's my instant gratification?

    Oh well, at least the paint will get a chance to dry and I won't keep constantly dropping spanners onto it.
     
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  17. Screwdriver

    Screwdriver Member

    Messages:
    6,476
    UK London
    I went all out bling!

    [​IMG]

    They were super cheap so they will be rubbish but:

    1. They're going into an area of maximum hazard with cutting oil and swarf to contend with
    2. They were the quickest promised delivery
    3. I can easily replace them with better quality items if required

    I just need to get this machine finished so I can make up my welding table and sort out the workshop.
     
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  18. Screwdriver

    Screwdriver Member

    Messages:
    6,476
    UK London
    Parts are ready.

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    Installed.

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    Damper is installed but not refurbished, just cleaned and a new bolt fitted.

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    Blade guides are in but I am waiting for the bearings.

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    Plenty more to do yet before I can fire it up. All the electrics for a start. Sounds trivially easy but I might fit things in a different spot. Might even build a new enclosure for the switchgear.

    Cleaned the clamp thread on the lathe, there was still a fair bit of crud deep inside the thread. Also chased out the nut with a home made scraper, it now operates perfectly.

    Meantime I need to make up some 1/4 20 finger bolts for the blade cover. There weren't any fitted, it's an odd size and I want to be able to open the cover without resorting to spanners. I also need to build a brake mechanism for the wheels. When you pullthe arm down from vertical, you end up scooting the whole trolley along!. I have a cunning plan...
     
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  19. Chillitt Member

    Messages:
    1,120
    Location:
    Cirencester
    Paddock stand! :D I have one for my Rapidor. Its a silly thing that works and cheers me up every time I use it.
     
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  20. Screwdriver

    Screwdriver Member

    Messages:
    6,476
    UK London
    Similar sort of thing but permanently attached and not that big! I just skipped a pair of paddock stands just for the space they take up. Awkward damned things to keep hanging about when you have three sets.
     
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