Multitools do not have backstops. What exactly are you doing so we can make suggestions for the correct tool.

Thanks Daisy. Bit involved. I need to make cuts in some large chipboard floorboards without cutting things that lie beneath, so the cut depth needs to be precise.

If it is pipes you want to avoid you can buy a pipe detector.

Yeah, I have one, and know where the pipes are anyway. I still have to cut directly over a pipe and there's no way round that but that's not really the issue (I have a piece of steel shim which will slide between the pipe, if I lift the board a fraction, and wouldn't do the blade any good but would stop the pipe being cut).

It's not a conventional floor. It's a bizarre DIY job (previous owner, home-made garage conversion, basically a big wooden box inside a double garage which we use as a utility room) but it was surveyed and the answer was "bit peculiar, wouldn't have done it like that, but actually fine in structural terms". It got building approval when it was built.

He's used thick 8X4 chipboards over 1.5cm high timber battens (and not enough of them to take the weight we need to put on it - two freezers, a dryer, washing machine and other stuff). They just warp the floor because the battens are random distances apart but often 2ft or so. Also, some of the joints are hanging.

Until now I've had the appliances on a weight spreader (a couple of heavy marine ply sheets with a rough-and-ready torsion box internal construction, spreads the weight across several battens). They been there for 5 yrs no problem but it looks odd and we're trying to improve the room (finally got the utility after 5 yrs!)

I investigated pulling the floor up and putting down deeper battens (also to improve the insulation) but that means replacing two doors, one of them external, because they only just fit over the current floor height (looking at doing that with mat trays).

But we downsized five years ago and have possessions to fill a bigger house, so the utility room is packed (can't even get at some stuff). Pulling the floor up means putting stuff in storage, and we're 10 miles from the nearest facility, that would take for ever and I'm nearly 70(!)

The compromise was for me to take up the floor boards under the current load spreader, put additional weight bearing battens down under just that bit, and relay the boards. But (I told you this was complicated) we had a leak last year and when it was repaired the whole room was decorated. Like, beautifully.

The boards fit under the skirting and I'm trying to be Mr Precision and do it without pulling the skirting off and redecorating it. Hence cutting the boards. There is mystery wiring which needs investigating round the room edge, under the boards, just visible in parts under the skirting. Obviously the electricity would be off at the consumer board but I don't want to cut that until I know what it is.

What I wanted to do is cut the boards so that a) they are smaller and a near 70 yr old with a slightly arthritic hand won't do self-inflicted damage lifting them and b) only remove the boards where I need to improve the weight bearing capacity.

Suggestion: get an electric saw that you can set at the depth required, but you would have to leave a margin away from the skirting board but this would still enable you to lift the floorboards up. We currently use a Makita battery saw which is very light and convenient. This is hubby’s recommendation and he is 71 with arthritis too so could be the way forward.

Thankyou Daisy I will look into that!!!