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Open HV Probe 40kV

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tggzzz:

--- Quote from: beanflying on April 22, 2019, 07:06:21 am ---
--- Quote from: tautech on April 22, 2019, 05:39:51 am ---
--- Quote from: beanflying on April 22, 2019, 04:24:02 am --- Also checked and based on your videos there is plenty of diameter for a secondary thin wall PLA/Kapton Taped inner tube for the Resistors and any above ground terminations to sit in the tip barrel (14mm bore but fitted with a 13.5x12.7 wrapped tube).

--- End quote ---
This is key IMHO ^^^
The handle should just be a vessel to enclose the construction of safe innards.

If, and only if the printed materials can be proven to be safe against leakage or flash-over may they be used in any insulation capacity.
We can never be sure someone with the printer files and a printer won't use an unsuitable filament.  :scared:

--- End quote ---

All things are possible you and can now get fairly easily get Conductive PLA https://www.proto-pasta.com/pages/conductive-pla laced with Carbon. Anyone making an electrical safety probe with it would truly deserve their Darwin Award :palm: There is other options out there but Styrene (ABS, HIPS etc) or PLA are clearly the better and easier to use options.

--- End quote ---

PLA and many thermoplastics are hygroscopic to some extent. Unless proven otherwise I would assume that would change the electric properties over time, e.g. it becomes more conductive.

I have not seen (because I haven't looked for) any measurements indicating whether or not that would be sigificant in this application.

beanflying:
H2O (pure) has a far greater dielectric strength than air for example and any amount of moisture absorbed will be more or less pure due to its origin. Discussion of moisture in filament is generally due to the issue of what there is creates steam when used to print something. There is no figures I am aware of re changed electric or physical data over time but is is massively hard to get even very high voltage to pass through pure water due to a lack of ions. Mine for example once a month maybe is the use case my HV scope probe will get over 1kV and I have meters already up to that point so maybe a silica pack and vac bag it.

If anyone is still concerned then styrene options are always there but they then come with some common solvent based issues (acetone in particular). That will include the Vintage ones vk6zgo mentioned a few posts back.

With accelerating/composting PLA for example both high heat (70+C) and high moisture with limited oxygen is needed. UV can effect some pigments. Refound some practical outdoor testing of PLA prints from Angus @ makersmuse in the Australian weather. Bear in mind a lot of these pots are SINGLE LAYER (0.4mm wall) I am printing @ 6 layers with 40% infill where needed.

https://youtu.be/qqNfa_zExRU

mnementh:
That picture makes me cringe; no less than that video we were just discussing. 

I'm not hand-wringing. I'm pointing out clear and obvious hazards in publishing the stls for this.  ::)

The intended manufacturing process and material simply and clearly are NOT fit for the intended purpose. Add to that the proclivity of dumbasses to just snurch and not read instructions, and the bottom line is that publishing these STLs is ethically the same as leaving a loaded gun lying around on the intardnet. :palm:

I'm not the only one here who can clearly see the clear and present danger this project represents; you discount those dangers at your own peril.

I've said my piece; I'm done here.

mnem
"Good luck! And may your god go with you."

tggzzz:
Yes and yes.

And I too remember Dave Allen fondly

beanflying:
For those who actually take the time to watch Angus's video in my last post will know the SINGLE LAYER vase mode prints suffered mechanical damage and are not the result of open air environmental, water or UV exposure. PLA needs very specific environmental conditions to breakdown without those conditions it is far from bio-degradable as numerous scientific studies have shown. Google it and do some reading of the scientific papers.

If your doubts are still with PLA then use ABS or HIPS like the commercial probes use and put up with its shortcomings like all materials have. Without having seen one in the flesh Pintek appears to still be using ABS based on it's cleaning warning against solvents http://www.pintek.com.tw/files/pintek/HVP-40.pdf PLA on the other hand is not effected by most solvents.

Part of the idea of this being open was to work on ideas and to improve the safety of the design and in a small way try and redress some of the youtube bs 'designs' that have little to none.

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