white tornado 1 Posted July 24, 2012 Share Posted July 24, 2012 Any tips on how to get the machine screws out of Harken Aluminium Cam cleats. I have a number of cleats where the corrosion reaction between Aluminium body & stainless steel machine screw has created a bond that so far has prevented removal, even using various solvents and serious hammers. Link to post Share on other sites
w44vi 17 Posted July 24, 2012 Share Posted July 24, 2012 I would use an impact driver, you can get them from super cheap, mitre 10 etc for about $10-$15 if that doesn't work you will have to drill it out Link to post Share on other sites
Guest Posted July 24, 2012 Share Posted July 24, 2012 Butane Pencil torch and an impact driver with the correct (perfect fit) bit. Sometimes it works better to heat it, cool it and then heat it again before whacking it with the impact driver. Google pencil torch - very handy bit of kit and good directional heat. EE Link to post Share on other sites
wheels 543 Posted July 24, 2012 Share Posted July 24, 2012 Honestly, buy new cleats. The anodising is stuffed and you will only have it all happen again, but much quicker. Link to post Share on other sites
Grinna 2 Posted July 24, 2012 Share Posted July 24, 2012 Would the use of something like TefGel to isolate the fasteners from the cleat prevent re-ocurrence of the problem Wheels? Link to post Share on other sites
TimW 1 Posted July 24, 2012 Share Posted July 24, 2012 Not using Aluminium is the obvious answer ! To remove the old screws you need heat but you are quite likely to damage the plastic on the cleat and so most likely will need new ones. Consider the Carbo versions of the same cleats (if they are up to the loads) as they won't corrode. Link to post Share on other sites
wheels 543 Posted July 25, 2012 Share Posted July 25, 2012 Yes, you should always use something life tefgel, even lanocote works well. Or you can also use a plastic spacer in some situations, like as used on sail track. I assumed "cleat", we are talking a horn cleat ????? Link to post Share on other sites
Murky 1 Posted July 25, 2012 Share Posted July 25, 2012 Slight tangent, given the original issue, but FWIW there is a Harken kit and accompanying Youtube video on how to give them a birthday once you get them apart. TimW 's carbo suggestion above might still be the better solution however. Link to post Share on other sites
ballystick 73 Posted July 25, 2012 Share Posted July 25, 2012 white T is a carbon creation enthusiast to the extreme, just look at his boats confirms this and he will be deleting all of those alloy bits for sure. What I have been given in the past was hydrofluoric acid for cleaning alloy wheel oxidation on cars - it made them like new - could that release the cleats. Surely there is a chemist in the crew.org group who could advise on such things.... Link to post Share on other sites
wheels 543 Posted July 25, 2012 Share Posted July 25, 2012 Hydroflouric Acid is something to be very very careful with. It is a very toxic chemical. No it won't touch the corrosion. You can try some sodium hydroxide. But the problem is that anything that is strong enough to desolve the Aluminium Oxide is also going to harm the good aluminium. Try heat with some breakfluid. Brakefluid does not run away from heat like oil does. Link to post Share on other sites
Guest Posted July 25, 2012 Share Posted July 25, 2012 Chuck the lot in some simmering water. Takes around 10min and all should become unstuck. May do some plastic distortion though so get ready to hold them in the right shape while they cool. Link to post Share on other sites
Guest Posted July 26, 2012 Share Posted July 26, 2012 White tornado, how about a bigger picture, are they on or off the boat ? whats the construction where they are bolted through on the boat ( wood/glass/metal????). If they are off the boat honestly throw them out and go plastic or carbo. buy the time you clean and prep them properly to use again. Wheels I'm guna bring over some tef gel and a few other things for an experiment with electric current transfer next time I'm working next door. What we have experinced with the super yachts you will find very interesting, and what will fizz through what. Link to post Share on other sites
idlerboat 116 Posted July 26, 2012 Share Posted July 26, 2012 well sort of all of the above. The bond between ally and stainless has become a modern boat problem. Beware you modern production boat owners ,,,,,, If you cant get an angle grinder to a bolt...or nut..beware ! If it siezes , how are you going to cut it off ? your mast step may well be held in place with a tapped ally plate bonded into the coach roof . All connected with stainless bolts or worse screws. Not to single out but some Bavarias for one have bonded mast step attachement plates. The force / heat / frustration to remove conneting fastners can be mind snapping. And once you strip the screw slot (X head)...or thread or fastener....it gets a whole lot worse. and you cant chuck a boat in simmering water. There is no easy anwser. It is an anwser in part to that question....."glass boats are bomb proof...arnt they ?" Duralac, lanocote,...and other electrical barrier coats may help. As a metal boat owner ....I am a little smug. Yep we deal with rust and ally: and ss still are a huge problem on our boats....BUT we spend our lives freaking out about it : ) ...and it makes us a little less nerdy when the metals of the world unite on plastic boats... Link to post Share on other sites
wheels 543 Posted July 26, 2012 Share Posted July 26, 2012 It always depends. So it takes a little thought as to how to protect what from where in what use. A coating like lanocote or whatever, is not about the coating protecting from corrosion, but the coating filling the void between threads and hole and thus water that could get in basically has nowhere to get in to. On my mast step, I made plastic bushes to keep the SST bolts off the ally step and seal the bolt head so water could not go anywhere. On the mast, any large SST component has a plastic gasket under it to maintain isolation. Link to post Share on other sites
idlerboat 116 Posted July 27, 2012 Share Posted July 27, 2012 As the saying goes " I am in furious agrement with you " wheels. What I was trying to point out is that a bucket load of older production boats (and others) whilst enjoying the obvious benifits of epoxy hulls, have never the less got some quite serious problems with dissimilar metals. These situations are very hard to undo in some cases. I am now a realest and belive that even though prevention is a wonderful thing......being able to replace easily is even better !! Regardless of what material...bonded in threads are going to be someones nightmare. I now think that it is a designers laziness to do that for boats that are meant to have a "life span"... Sure on your short term racing rig go for it (whydontyoubond everything)... I will give again an example. A fully bonded in alluminium ...tapped deck plate below a mast that bolts (with SS bolts) the mast step to the plate. BAD BAD BAD... Alternative ?... same everything but the ally plate is boxed but not buried...and it is not tapped but drilled. With nuts on the underside. Both will lock up. First no hope...second you have half a chance becuase you can get to both ends of the fasteners.. ....BUT more importanly...YOU CAN CUT THE F##KER OFF !! and then carmly start again with dignity and a generaly sunny disposition ..smiling to the peo0ple who pass by ..reminding all of the joy that is yoting... Link to post Share on other sites
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