Is it a balanced flue heater? Just had a look, and it would appear that it is not a balanced flue device. A balanced flue would have made for a much cooler flue/air inlet pipe.
If it's the secondary that is the faulty winding, and the wire is solid core, you might get away with using solder, if the two wires are filed to one-sided points (i.e. wedge shaped), with the filed surfaces brought in contact together, and the join made by flowing solder between them as thinly...
Set the bolt to be tightened so that the bolt is vertical, and fitting a standard socket and wrench to the bolt doesn't apply any turning moment. Determine a suitable point on the wrench handle to apply force horizontally at right angles to the wrench handle, using a spring balance, mark it...
The EOS 700D does have live view.
If the live view on a camera allows electronic zoom, especially up to x10, then it's possible to use it to get the best focus possible on the subject of interest.
As well as the suggestions above, check the circuit board for dry joints.
The power lead connection to the circuit board looks like a push fit terminal. Make sure it's OK.
Lead acid batteries don't really like being overcharged, which is what it might be going on here. The gas production tends to disrupt the coatings on the plates over time, drastically lowering their capacity. The charger may complete the cycle because it is sensing that there is an overcharge...
In modern digital telecommunication methods, a sinewave signal, at a single frequency, is passed through a simple phase shift network to shift it's phase by 90 degrees. The result is two signals. One that is "in phase" (the "I" signal) and the other that is "out of phase" by 90 degrees (the "Q"...
Not sure why mains voltage solar thermal pumps need programming. The controller's default values work pretty well. Mains pump controllers, like the Worcester TDS10, are OK powered on all the time, and only turn the solar thermal pump on when the solar panel heat exchange fluid temperature is...
Wax isn't a good choice since, being an insulator, contact with the table is not really going to be reliable. Oil, too, can cause issues, if a piece being welded is then turned over to do the other side, the oil is likely to contaminate the weld.
Starret split collet. The link below is for a larger size (9.5mm).
https://www.ebay.com/itm/126236684500
This one's 8.0mm:
https://www.grainger.com/product/STARRETT-Collet-25SC-30C128
The heater only comes on only once every ~45 mins, so there must be quite a substantial thermal mass in there. The temperature swing is nearly 2 degrees, which can make quite a difference if the incubator is being used for doing something biological. Think Q10. A 2 degree swing could result...