Operation
These machines use cams to operate the feed, clamp and grinding head. The "Grind Cam" raises and lowers the grinding head while the "Feed Cam" both indexes and clamps the cutters.
The T-REX model has three modes of operation.
"OFF" - Sharpens left and right hand cutters without detection
"AUTO" - Uses cutter sensor to detect and grind two cutters in a row.
"MAGNET" - Uses a magnet to detects and grind two cutters in a row.
The machine uses four sensors to operate automatically.
1. The cutter sensor "looks" at each cutter and determines what hand it is.
2. The proximity switch senses a magnet placed on a cutter to correct the grinding sequence for out of sequence cutters. It also serves as a counter to automatically shut off the machine.
3. Two other sensors are located inside the machine. One in the feed motor to count motor revolutions and another behind the idler gear which checks the bevel angle of the grinding head.
Adjustments
There are four main adjustments which need to be made when changing between different size chains. (see previous page)
1. Limiting the feed stroke.
2. Setting the feed pawl height.
3. Centring the grinding head.
4. Chain Clamp
Limitations
1. The T-Rex model is not recommended for use on ¾" harvester chain .
The Handi-Rex model is more suited because of its "hands on" nature.2. The T-Rex model cannot automatically sharpen chains with three or more cutters in a row on the same side of the chain. Two is the maximum.
3. Chains with three or more tie links in one section of the chain must be stopped at this point with the magnet, as the feed stroke will not cope with more than two tie links.
4. Chains with double tie links cannot be sharpened using "AUTO" mode as the sensor will not ‘see’ the cutter after the double link. Only use "MAGNET" or "OFF" mode on these chains.