Thread: reconditioning a windmill (long long story here)

Latest job to come up has been the reconditiong of a Comet 12ft windmill.... Originally installed sometime in the mid-late 1960's, been in continuous use ever since.. Only repair since that time besides general oiling has been a repair to the crank shaft where the bottom hole had worn egg shaped..

We generally do all our own windmill repairs ourselves, we have not been very impressed with the quality of work provided in the times we have used contractors to do major repairs.... The last incident where we had a major rebuild done on a 12ft Z pattern Southern Cross, resulted in a $1700 repair bill 3 years after the job was done due to substandard workmanship, a shaft was knurled to increase it's diameter to make it better fit a hole, subsequently it worked loose a key fell out and the wheel was free wheeling on the shaft....... $1500 of the $1700 bill was just in crane hire by external contractors... In any case this is not an isolated incident of substandard repairs we and our neighbours have had with the expert contractors...

Anyways back to this 12ft Comet... Due to age I suspected some preventative maintenance should be done, as in very dry times it is the only water source in the paddock.. At the moment water is in abundance..

A year and a bit back I came across a palfinger crane on ebay... In melbourne, at a not too expensive price considering it was only 11 years old and upon calling the seller was told he had been using it on his truck but had since removed it has someone backed into his truck writing it off... It also came with a wireless remote control.. I purchased it and when I got it home discovered the old "let the buyer beware" saying ringing true.... If the seller of the crane is reading this, you are a lowlife scum sucking ########... Yes it was indeed only 11 years old, but had come off a boat of all places, had suffered from rust pretty badly in the base..... Did not have original outriggers, but came with a couple of semi trailer legs and the radio remote had been flogged off a different crane and had never been used on this one...

I propped it up against a post and after contacting Palfinger, nearly had my head torn off after I asked how would I go about welding a new base on it... Lets just say nicely the OHS rules and my idea of repairs did not see eye to eye...

The crane sat for a year.. reminding me of the ######## seller... With the saying fortune favours the bold I said fuk it and I will not achieve anything if I do not try..... OHS rules do not apply to owners who are free to do whatever dangerous practices they want provided they and they themselves along with only their property are the only ones put at risk.. I ordered steel low hydrogen welding rods and fabricated a new base.. For the record it is a 9.5metre tonne model..

Fate soon saw me get given an old old Toyota D6000 truck when I was chatting about my intentions for the crane... I was told it ran... I laughed... He assured me put batteries in it and it will go but it has a blown head gasket... I was just going to use it as a pull along trailer and use a tractor as a hydraulic power source for the crane...

I had it sitting at home for a couple of months and curiosity got the better of me, so I jump started it..... Bloody thing ran after sitting for several years... Head gasket was indeed blown.... Lucky the person who gave it to me had a new head gasket for it.... I removed the rear head (it has two heads) and devconned up the pit marks in the block (reason why it blew in the first place) and seem to have cured the problem..

The crane was soon fitted to the truck and tested out using a tractor as the power source for the hydraulics... A load of 500kg was placed at full extension..... Seemed to hold it OK....In for a penny, in for a pound, lets double the load to 1100kg the cranes rated maximum load at full extension... Of course it would never be able to lift that by itself as the max hydraulic pressuse the crane can handle is 4250psi while the tractor does around 2300.... I lifted the load onto the crane and gradually let it take the load, half expecting something to go snap.... IT HELD!!!! woo hoo, I was wrapped... Time to get serious about this now....

The plans soon changed from tractor hydraulics to self contained unit.. Ebay provided a new old stock Italian hydraulic pump.... Only small @ 16l/min flow but does 3500psi..... Ebay also provided a 9hp chinese engine... I fabricated up some proper outriggers using the provided trailer legs... They are rated at 30 tonnes wit a 14 tonne side load, so should be adequate ..

Using the workshop I fabricated a connector to connect the pump and motor together directly.. I cursed European standards and the strange things they do... The pump had a 1:8 taper on the drive shaft along with a tapered key.. The auto drive top slide on the lathe came quite in handy for doing the taper, and my slotter, the head rotates so I could do the tapered key... Somehow the finished part fitted...

The pump also has some rare German flange ports on it so parts had to made for it as well as an adapter to a more common connector...

The hydraulic tank came from a previously failed project and hoses were purchased to connect it all together (christ hydraulic hoses are expensive)

All fitted together, all has worked quite well...

An extension was fabricated to fit int he crane so it can lift to a height allowing windmill heads to be removed... The extension was tested.... Firstly lifting 200kg up to full height of 44ft..... That was doubled to 400kg.... Finally 550kg (a 44 of concrete) was lifted to full height and moved around to test for stability... Would not want to lift anything heavier but it seemed OK....

Which leads us back to the Comet windmill reconditioning.....

After contacting Comet Windmills Australia and they telling me the complete head weighs in at 360kg I waited for a still day and headed off to start the job.... For those not in the know, windmills are very dirty things after they have 40 years of semi solidified oil and grease over them... After tying the tail into the on position (so it does not swing around and unbalance everything) and tying down the ball race so the ball bearings the turn table run on do not go everywhere I disconnected the connecting rod and removing the two bolts that hold the head on, it was time to do the lift.... I had an endless chain connected to it with the intention of lifting it free of the tower first then slewing the crane and lowering it to the ground...

I tool the weight with the endless chain... However I did not have the balls to lift it free of the tower with me being up there with it.. To be honest we had not done this before and I had no idea how balanced it would be when it came free of the tower.. So I went down to the crane controls and hoisted it up with it... When it came free of the tower, it just hung there nearly perfectly balanced... Slewed around the lowered it to the ground ready for dismantling...

Got it dismantled and back home..... 3hrs after we left... Doing it the old way of using a gin pole and dismantling it in pieces while still on the tower would take a lot lot lot longer and be much harder..

Have got the parts home.... Got a large plastic vat and filled it with water and 30l of the Repco degreasing solution which is a concentrated caustic solution and placed them in that for a day, then pressure cleaned them, then put them back in for another day.. It cleaned everything up very well, stripping most of the paint as well..

Have procured paint, new bolts for the rusted ones, discovered the old tank bolts that bolts the sails on were a very obscure 9/32 x 20 tpi size... They are being replaced by 8mm gal hex head...

The ball bearings that the head swivels on are worn down by nearly 1mm (originally 5/8 size)

So at the moment have every thing dismantled mostly clean and some painting done... Shoudl hopefully get it finished later this week time permitting...