Redneck cement mixer fix!

[RMS]

Yesterday Patrick & I decided to fill a shallow hole in the barn floor (used to store my Land Rover projects, hence the LR content    ).

I dragged my 40 year old cement mixer out of the bushes behind the garage at our old house, un-siezed the wheels so it would roll, and plugged it in at the new barn.

No problem - a bit noisy at first but some grease lathered on to the pinion and ring gear, and squirted into the nipples for the pinion drive, and it quietened down nicely   

Just about to start the first mix and it wouldn't switch on!
I remembered that it always had a slightly dodgy on-off rocker switch on the side of the motor, so took the cover off and using a testing screwdriver found that the neutral wasn't switching.
So I sorted that and started the first mix.

Just about to pour the first mix and the motor started struggling and slowing down   
Managed to tip the first load then looked at the motor - I assumed it might be bearings as it had been out in the elements for the last 20 years.
However, taking the belt off I found it spun freely, but was definitely running slow when plugged in, even without any load.

So what do you do when you've already started a pour, still have 450kg to go and no spare motor handy?

Easy - pull the pulley off the motor, fit an M12 bolt and nut through the pulley, fit it to a very old electric drill, and bungy said drill to the motor frame!



Ok, it turned the wrong way (1950s technology hadn't even thought about reversible drills!) and was slow (500rpm), but we managed the next 20 or so mixes with no problem.
The drill, full cast alloy case, didn't even get warm!

Checking the motor today, I suspected either a winding shorting out or the run capacitor failed.
Using my optical tacho, I found the motor was running at around 740rpm, about half of its rated speed.
I happened to have a spare capacitor from the industrial fan units which were in the ventilation roof turrets in the barn, so hooked that up in place of the original and it ran at 1475rpm.
It wasn't anywhere near the 10uF original, but seemed to do the trick for testing.
So now I've ordered a new capacitor and hopefully will have my faithful mixer mixing again next weekend 

Cheers,
Robin.

[romanyrose]

G'day Robin, i love it , throwing nothing away just in case you might need it one day , a man after my own heart so to speak. Good thinking as always. Brad .

[gossamer]

Brilliant!

I keep having to put bigger wedges in mine to keep the belt tension up.
I may fill it with kiln dried sand and old nuts and bolts in the summer to polish the drum and rescue some original fasteners just incase I get series one that may be inspected by the club's bifocated fastener accountants.

[RMS]

Matt,

If yours is a similar design to mine, to adjust the belt tension the whole motor housing/cover moves up and down on the frame by loosening two bolts, one of which you get to through the hole in the large pulley.

I replaced the capacitor (£2.32) and refitted the motor this week, and Patrick & I have just mixed another 1/2 ton of concrete this afternoon

Still going strong after 40 years of neglect, and the old drill can go back in the bottom of the bench for another day.

Cheers,
Robin.

[gossamer]

Not as heroic as yours Robin but a long suffering piece of kit.

A pain in the stores when not in use but when one needs concrete a plenty one forgets the number of times one has tripped over it and cursed.

When I built my inventing shed I moved several tons of really good topsoil. The soil was full of pebbles (boulder flint sort of thing).

It seemed a good adea to keep the soil coz the ground around here is mostly clay, so I used the mixer to break up the clods of shovelled soil and the pebbles rolled to the top. They were creamed off and the six yard skip I ordered went away full of clean pebbles. I wish I'd spent the money on gabions, I could have built another bomb proof shed!

Biggest problem with owning a mixer is that folks ask to borrow it and it usually comes back knackered.

[Viamphie]

Nice to know there are plenty of mixers out there when I get to laying the base down for my super workshop.

[gossamer]

Give us plenty of notice!