I bought this grinder over a year ago for stainless steel grinding, blending, and polishing for the production of food processing equipment. Sure, the shop supplies grinders and variable speed grinders, but it’s nice to have my own that won’t walk off mid-job. I read other reviews prior to purchasing, and the main complaint I saw was the tool getting too hot. I expected that, as all the variable speed grinders I’ve used - Makita and Bosch - have all gotten quite hot with the heavy use typical of a full day of polishing off hundreds of feet of welds. However, this grinder is essentially their brushless 5-inch grinder (DWE43214, which I also own) without trigger lock and added a lanyard attachment point and a variable speed controller. No consideration was taken for the decreased airflow when the tool is operating at a lower speed while putting out enough torque to make the tool useful (granted, this grinder doesn’t bog down like the brushed motors in competitors’ products). The decreased airflow leads to less heat removal from the tool, and heats up more than the constant speed grinder. There’s some wire mesh used to “filter” the air flowing through the tool, but it’s not as fine as a drier lint trap. This ineffective filter, coupled with the fine abrasives used with polishing, the cloth backing on some of the abrasives, and the inefficiency of the fan at lower speeds, leads to build up of dust inside the tool where the air should be flowing and the airflow is not enough to make sure dust blows straight through the tool, further blocking airflow, and reducing the ability of the fan to keep the tool cool. Several times since I bought the tool, I’ve taken the covers off to blow dust out of the tool. About once every other month to once a week, depending on usage. I just got done really opening up the tool, pulling the head off and pulling out the rotor, to get every spec of dust out of the tool, only because the conductive nature of grinding dust has lead to the head to become energized - 50v with the tool just plugged in, spiking to over 220v when pulling the trigger. Yes, I’ve had a few nasty shocks recently. Now, there’s just 5v to ground from the exposed metal to ground. Going forward, I hope someone at Dewalt reads this review. I’d like to see an additional small motor just to power the fan for a variable speed grinder, and make use of Dewalt’s centrifugal dust elimination so dust doesn’t build up in the tool (the fan could also run when hot and not in use). I’d also like it if the next one had soft start - the motor puts out a lot of torque instantly, and before I got used to it, it caused additional work for me as my attachment would impact the workpiece and leave a deep gouge that would have to get blended and polished out. On the positive, after completely tearing apart this grinder (quite literally), it doesn’t heat up as fast as other variable speed grinders even with completely blocked off airflow. The protection systems built in to the tool are effective at protecting both the user and the tool - stops rapidly when releasing the trigger, stops instantly if the attachment gets bound up (I’ve been attacked before by bound up cutting wheels, though I don’t use cutting wheels in this particular grinder), and shuts the tool off if it overheats before damage can be done to the tool. It also maintains a near constant speed even under an increased load. And despite its shortcomings, I still prefer this grinder over the Makita and Bosch grinders my employer has available to me in the shop. As long as I can keep it from shocking me.
