Roger Bisby Grinds it Out With Flex

Roger Bisby Grinds it Out With Flex

Roger Bisby is grinding out a result with the Retecflex

In essence, this Retecflex grinder and sander is an angle grinder with a fancy dust extractor permanently attached to its side – but it is no ordinary angle grinder.

It is a 1,400 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 features, such as dust sealing on the switch, which put it in a different league to your bog standard angle grinders – but the angle grinder is not really the story here. It is what this grinder does that makes it worth its non-angle grinder-like price tag.

By that I mean it isn’t cheap, but, if you are engaged in refurbishment, it is a tool that will earn its keep over and over. You can also hire it from selected hire outlets.

What does it do?

It removes concrete, granite, render, adhesives, paint, various residues and, due to its stepless depth adjustment, it will even tackle hard-to-remove wallpaper from a wall while hardly touching the plaster.

What’s more, it does this 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 85mm.

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.

Features at a glance

Max. disc diameter: 115mm
Max. milling head Ø: 80mm
No load speed: 1,800-5,200rpm
Power input: 1,400 watt
Power output: 880 watt
Tool fixture: M 14
Size (WxLxH): 390x198x150mm
Weight: 3.1 kg

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