This thread will serve as the official update thread for Titan batch #2.
I’m in for 1 sexy Titan box. It even comes with a magnet!
Now to play the waiting game…
I see goal was originally cost, and now it’s backers, is that correct?
Does 1 backer with 2 magnets count as 1 or 2 backers?
Honestly not sure… haha back 2 and we’ll find out! It’s really only that way because I think the display of money raised too vulgar… but I can change it back if it makes more sense.
Not gonna be me unfortunately, I’m only considering getting 1 more.
On that note, I wanted to ask about sterilisation. Is there a stretch goal or something for plasma sterilisation or will they always come sanitised? (more asking so I know which if any to reserve for a surgeon to install who might care more than my piercer).
Backed it first thing about an hour ago, can’t wait!
Hey Amal’s definitely still sleeping, but I can say for certain the magnets will be delivered sterilized (or clean or whatever medical definition). DT won’t be sending people any implants raw in a baggie that you have to sterilize yourself, period.
What form that will take I’m not sure, but it will likely be the same technique as was used on the first batch.
Really, that’s the bit I want clarified. If it’s same as last time, that would be sterilised with low temperature plasma, however it could also be sanitized with chlorhex like flex implants
They will ship in chlorhexidine vials. The plasma was a huge pain and super expensive.
I think once could probably autoclave it after the fact without significant loss of retention if they are feeling paranoid, no?
Please don’t do that, you’ll be disappointed. Autoclaves get hot enough to significantly diminish magnetic field strength (look up Curie temp). It happened to me on my first magnet cause we didn’t know what we were doing and it was basically a useless lump once it was in my finger.
TL;DR: @Satur9 is absolutely right, , unless you want it even weaker (about 66% of original pull strenght)
Long and boring exploration of max. operating temperature on neodymium magnets and the impact of overheating on pull strenght
Shit, you are right. I assumed that since the Curie temp. for neodymium-iron-boron is supposed to be about 310-320C, and no commercial piercers autoclave gets even near that (121-124C (some go as high as 135C) for 20 minutes at 2 bar), there shouldn’t really be a problem.
But I looked a bit into it, and apparently, irreversable demagnetisation (some %) starts to occur between the maximum operating temperature (dependant on the permenance coefficient - funnily enough, the shape matters) and the Curie temperature. And the max. operating temp. for N52 magnets is apparently surprisingly low (about 60-65C, dependent on shape, varies by source).
I calculated the permenance coefficient of a Titan (N52, 3x2 mm disc, 0.4 mm distance) to be 2.04 and plugged it into the K&J Magnetics Demagnetization curve calculator at 40C operating temperature (for a finger, more accurate is probably 2-4C below core temperature, but it is closer to 40C then 20C - doesn’t really matter since the operating point is on the linear part of the normal curve in both cases) in free space. The max. operating temperature is thus estimated to be between 80C and 100C (looking at the intersection of the load line and the nearest “knee” of a normal curve).
Fig. 1: BH curve for a N52 magnet, operating temperature 40C, permanence coefficient 2.04, from kjmagnetics.com/bhcurves.asp
Heating the magnet to 120C and cooling it down to 40C, the pull strenght (closely related to MGOe, eyeballed from B and H in the graph, using absolute values, 43 MGOe at 40C when pritstine to 29 MGOe after being heated to 120C and cooled - 14 MGOe difference) is reduced to about 66% of its original value.
Keep in mind that magnetism is dark magic to me and it is completely possible I screwed some calculation up completely
Of course all of this is for a “bare” magnet → the heat mass and conductivity of the titanium casing along with the time spent in the autoclave at 121C would impact what temperature the magnet actually reaches, thus skewing the the actual reduction a bit (but I suspect not much, depending again on the time).
Given how small the pull strenght is to begin with, I’m sure we want to keep as much of it as possible
I was just wondering, because I was reading a couple papers that explored the impact on autoclaving on magnetic dental assemblies, that stated there wasn’t a significant impact (1-14%) on retention force or attraction force - then I realized that it was not applicable, since they use magnets of a fancier composition, and different shape etc.
just backed mine
I assume more than 30 backers is possible, right? So 30 is the minimum, and the campaign runs until 14.4 anyways?
yep… it’ll keep going until April 14th 23:59:00
We’re already at 21, I imagine that if we aren’t by the end of the week, wait til Friday when everyone gets paid.
Damn, wish I’d gotten my number, are the order numbers sequential? Mine ends in 41 lol.