|Clive Hartland||17/09/2018 09:51:11|
2515 forum posts
The anodising is graded as AA10, AA15, and AA25 denoting the depth and toughness, durability. ASA 25 for things like shop front surrounds. All done in the caustic bath and then anodised. A quick flash anosdising is not much use as it will wear away quite quickly. I have seen skirting boards 4 meters long being anodised for a building in London. some were rejeccted due to fading/change in colour over the lengths. Easily re-done, the colour, a bronze colour which was quite hard to keep the same through a batch.
|Swarf, Mostly!||17/09/2018 11:33:01|
|516 forum posts|
Re HARD anodising:
Many years ago I had visibility of a project that employed many aluminium alloy parts that were hard anodised. So, the following from memory:
It was found that hard anodised parts 'grow' by an amount that will prevent close fitting of parts but is not always easy to predict. It was also found that the hard anodising film is vulnerable at sharp corners and sharp edges. So sharp corners and edges had to be rounded.
|Neil Wyatt||17/09/2018 16:34:54|
17326 forum posts
I was boring an eyepiece adaptor out to take 1.25" eyepieces. When I got to just over 31.75mm a piece of 1 1/4" tube would just fit, but my collimator with a body made of the same tube, anodised, wouldn't. I was taking sub 0.01mm cuts to creep up on when it would just fit without force.
Of course now I've anodised the adaptor the collimator may not fit - but not important as it seem EPs are generally a few thou undersize while the 'sockets' are generally dead to size. Odd as usually shafts are to size and the hole adjusted to give the required fit.
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