IR6500 Rework Station Modification - Ineffective bottom heater due to overly thick glass

First of all: get the original manual for the controller HERE. The description in the IR6500 manual is an unreadable desaster.

It did not take me long to realize that the thick glass of this rework station is absorbing most of the energy from the bottom heater. The 800W of the heating element were basically ineffective.

Also, the station has trouble with the peak temperature of 230°C in the reflow program. I need to adjust the top heater very close to the chip if I like to reach it. Closer than I feel comfortable with. The manual says >2 centimeters. That's actually the maximum distance. Further away and the peak temp will never be reached. If a window is open or a fume extractor running, it is even worse. I think that a good heating support from the bottom will stabilize the temperature.

I got inspired by this YouTube video.

Screw the warranty, I want this thing to work! Let's remove the top:

Oh dear, I have used the station only a dozen times and the temperature sensor shield was already burned and coming off. The sensor had no contact with the heater anymore. This thing gets too hot for any glue. A stupid design.

This is garbage. I am not interested in the temperature of the heater, anyway. I want to know the lower temperature of the board, if anything.

The sensor has a rugged, metal sleeve. So let's pull it outside through one of the slits:

The downside of the top cover:

Unscrew the frame that holds the glass and remove the glass. This thing is really thick!

I got a metal grill from a hardware store. I cut it to the right size and screwed it to the cover:

The difference in heat radiation is remarkable. The glass takes everything away!

Sweet, now let's do a preheater test without running a program and measure a few things:

With the bottom temperature set to 100C, the board heated up nicely to the specified temp in a few minutes. Note that with the glass on, the board would go up to about 40C max after ages with the heater set to 250! 

The heating element has around 300C, which should be well inside its spec.

Well, it is no surprise that a relatively cheap chinese rework station is not quite finished and has a sloppy build quality. On the other hand, those things are simple and easily tweaked.