I recently got scammed on an order of a cheap melting point apparatus from India and started to think about making one myself.
I mean, it’s just a heated aluminium block with a thermostat and a magnifying glass after all. Which is a pretty exact description of a 3D printer
hotend.
It shouldn’t be too difficult to use an Arduino and some repurposed 3D printer code to fairly exactly control the temperature of a 3D printer
heating block, and drill slots for capillary tubes in it. Place a lens in front of it and ta-daa.
The solution feels so easy and obvious that I would expect someone to have done it already.
Is there?
[Edited on 20222222/7/25 by DocX]DocX - 25-7-2022 at 12:04
So basically, something like this:
[Kr310.99 52% OFF]Creality 3D® Full Assembled MK10 Extruder Hot End Kit med 2PCS https://ban.ggood.vip/12iDA
Using an arduino it wouldn’t be too difficult to make perfect programs for ramped heating and other nice features that otherwise would cost a lot.
[Edited on 20222222/7/25 by DocX]Sulaiman - 25-7-2022 at 17:49
I expect that the most time consuming and/or expensive part will be accurate temperature measurement / calibration,
So I'd start the design by iteratively deciding on desired accuracy vs. the cost of calibrated measuring device or self-calibration (eg reference m.p.
samples)DocX - 26-7-2022 at 02:54
Of course you're right. I'm thinking the alternative for anyone on a budget would be the old thermometer in oil bath taped to a test-tube. So if this
contraption can outperform and outsmart that, it is worth the effort.
Outsmarting wouldn't be too difficult. After all, we have the power of code to help us achieve all kinds of neat tricks.
Outperforming to a degree where adding the extra effort is justified requires a bit of ... extra effort. I guess a decent thermocoupler would work as
a calibration tool.
First off, one would need to calibrate the thermistor in the heating block. Not too difficult.
Secondly, one would have to calibrate the heting block itself. This should also be easily done by inserting the thermocoupler wire into the slots for
the capillary tubes. Any discrepancies to the thermistor measurements can then be corrected in the code.
And then finally, as you say, a bunch of reference samples. If one wants that extra edge of exactness.
arkoma - 26-7-2022 at 11:03
aga designed one eight years ago, using a soldering element instead of a 3D hot end, and he wrote arduino code for it. Here's the link:
Fantastic! That's exactly what I'm gunning for. I thought someone would've already been down this road, and of course they had.
I love the addition of a USB microscope for magnification of the sample.
The neat thing about using 3D printer parts is that there's already a lot of ready-made code floating around, so you'd have half the work already cut
out.
I guess this is another one I have to add to the long list of pet projects on my to-do list.
