Roger Bisby grinds it out with the Retecflex from Flex.
In essence this Retecflex grinder and sander is an angle grinder with a fancy dust extractor attachment permanently attached to its side but it is no ordinary angle grinder. It is a 1400 watt German built angle grinder with electronic speed control, soft start and restart protection so it doesn’t start up after a power interruption. It also has high torque in low speed settings so you can really engage it in the job of grinding off concrete and other hard surfaces without fear of it stalling. There are a number of other features such as dust sealing on the switch which puts it in a different league to your bog standard angle grinder but the angle grinder is not really the story here. It is what this grinder does that makes it worth its un-angle grinder price tag. By that I mean it isn’t cheap but it is a tool that will earn its keep over and over if you are engaged in refurbishment and you can also hire it from selected hire outlets.
What does it do?
It removes concrete, granite, render, adhesives, paint, various residues and even, because of its stepless depth adjustment, it will tickle hard to remove wallpaper from a wall while hardly touching the plaster with speed and ease and most importantly with very little dust escaping from the dust guard. The fact is that this machine can do so much that it took me a fair while to get my head around the variety of attachments they sent along and I am still not completely sure what they all do but I got the general idea.
I have seen the guys who fit granite worktops using them to grind and polish the worktop to a mirror like finish. You can of course do that with a wet polisher but the reason this Flex machine has become the industry standard is because it is a dry machine with excellent dust extraction that allows you to work in an occupied building. This machine is also very popular with floor layers for removing adhesives and even taking the humps out of screeds. It turns, what could be a long and arduous job into something that can often be achieved in half an hour or so.
Less is more
The spindle is M14 so in theory you could use third party attachments on the grinder but even though the maximum disc size is 115mm the maximum milling head is 85 mm. That simply means that when you are removing a lot of stock you don’t want the whole of the head circumference employed. For one thing it would strain the motor but it would also run the risk of clogging up whereas the way it is designed means there is plenty of space under the hood for a good flow of air to take the dust away into the extractor.
The dust hood has one flat edge, rather like the Flex Giraffe sander that I tested last year and the idea is that you can grind right up to the internal corners of a wall or floor. If you don’t need the flat edge you can spin a section of guard around to complete the circle. Also, like the Giraffe sander, this machine uses the click hose system so you aren’t frigging around with adaptors or worrying about the hose falling off and the dust escaping into the room.
I can think of many jobs in the past such as tanking a cellar where this would have turned days of chipping off paint from brickwork with a needle gun into a few hours work. I can also recall attacking a recreation centre floor with scrapers and even a blow torch at one point trying to remove the old adhesive it took three of us four days to clean that subfloor and from my small test jobs I think a machine such as this would have done it in a day and it wouldn’t be a hard day at that.