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Tenma Mini SMD Preheater
SMD preheating plate
Equipment Information
Status Unknown
Manufacturer Tenma
Hackspace Information
Induction Required Yes
Induction Information Here
Card RFID Enabled No
Owner Tom (On Loan)

The Basics

This preheating unit allows you to keep a board at a set temperature while reworking parts on the opposite side. It is helpful to minimise board warping during rework, which can damage delicate BGA parts. This device is also very useful for repair of boards, as you can heat the bottom of the board whilst reflowing components on the top side (think Xbox 360 and PlayStation 3 motherboards, or smartphone CPUs.)

Do not attempt to use this unit for anything other than its intended function. It is not a hot air gun and it cannot be used to desolder parts, by itself. This is a fairly infrequently used item. You are likely to know when you need to use this.

In a typical application a board would be preheated to 225C whilst a hot air gun set to approximately 300-350C is used to rework components on the top side.

It uses a 600W heater and contains a fan, plus a small control circuit. Control is very basic using a simple "bang-bang" thermostatic control relying on the thermal mass of the heating element to keep the temperature steady. The temperature can be adjusted using the control knob. The temperature IS regulated, so you needn't worry about overheating your board if it is set to the correct temperature.

There are a pair of magnetic board holders stuck to the unit which allow you to mount a board over the outlet.


You must read the safety documentation in this link before using this equipment.

The outlet can get VERY hot (over 300 degrees Celsius!) Do not touch the outlet or the case of the unit while it is hot.

When heating a board be careful of connectors made of plastic. They can melt and produce fumes, which for some types of plastic can be carcinogenic. Also be careful of tantalum capacitors and lithium batteries, both of which can burn or even explode if overheated.


After use, please set the temperature dial to 100 C or lower and let the unit cool down (with its fan running) for at least two minutes.

This will minimise wear and tear on the non-replaceable heating element.