Wednesday 11 July 2018
The finished boiler cover, primed with thinned down undercoat and finished with two coats of gloss
This low-level boiler is an eyesore, and making it more pleasant to look at is long overdue
A table saw will make light work of the cutting, but one could also use a hand-held circular saw
Use a large compass to pencil in the required curved section on one of the pieces, and mark the pivot point clearly
Use a jigsaw to cut out the shape, but leave 2 or 3 mm on the waste side of the line
Fit a large trammel bar to the router and using the pivot point previously marked, swing the router round to trim the waste neatly back to the line and blend in with the straight section
Use this first piece as a template to mark out the other two pieces, and again saw round the curve just clear of the line
You could trim the other two to shape in exactly the same way, but I find it easier to use the first one as a template for the router, so stick it very carefully onto the next piece using double sided tape
Then use a bearing guided trimmer to follow around the template and trim the other piece back to be a perfect match
I cut out three pieces, but realise now that I would have been better with four or five to minimise the amount of distortion during gluing. The mould was formed by screwing these three to some scrap panels of chipboard fixed at right angles
The MDF panels bend quite easily, and is not necessary to damp them in any way. To get two good sides to the cupboard wall it is obviously necessary to laminate two sheets together with the cut sides facing inwards
Start the lamination process by pinning the first sheet to the top of the mould, and bend it carefully around the curve, giving it time to take up the shape rather than forcing it down
Cover the exposed face with a film of PVA glue using a brush or a roller, but be aware this does use up serious quantities of glue, as a lot of it disappears into the grooves, but it will build strength when it dries later on
Coat the face of another sheet and then stick the two faces together, holding them tight on the mould using a variety of clamps and straps. Be careful here of distorting the shape between the supports by overenthusiastic tightening! I was not and had to redesign the door as a result, as you will see later
Leave the job overnight for the glue to thoroughly cure, and you should end up with two perfectly curved but rigid panels when you return
Dismantle the mould and use one of the curved MDF pieces as a base for the cupboard, cutting it to fit round any pipe work if necessary. Cut a couple of softwood uprights tall enough to clear the flue, I used 40 x 40 material
Cut the bottom strip off one of the curved panels with a jigsaw and then plane the cut edge perfectly square
Glue and screw this in place around the baseboard, working from the middle outwards to make sure any gaps are pressed out
Take care with the screws, as I discovered that the inner laminations are prone to breaking out if you drill too close to the edge. Donnâ?t worry about using plenty of screws as they will be covered by the trim which is fixed later
Now, you can fix the uprights in place, screwing through the baseboard and through the ends of the curved section. Make careful to make sure that these uprights are square to the edge of the strip and the baseboard itself
Cut the other panel down, leaving it short to form an opening for the door, and then glue and screw this in place adding a couple more uprights to provide some extra strength
Whilst it dries, screw another of the curved MDF pieces from the mould onto the end of the uprights to form the top, again making sure everything continues to remain square
Finally fit the top curved section using sash cramps to pull everything tightly together to effectively and minimize the joint lines
I planned to inset the door flush with the rest of the curve, so left the necessary rebate on the uprights. I changed my mind later as the laminated piece left for the door was not particularly flat. A quick redesign was called for, and I decided to use a separate solid piece, fitting it over the opening, so now had to use strips of 12 mm MDF to fill in the rebate
The top is a piece of maple veneered MDF cut out in exactly the same way as the base boards using the router with the trammel, but remember to make it bigger to accommodate the trims that are added later
The top and bottom trims are made from homemade bendy 12 mm MDF! I had to kerf this myself using the multiple grooving jig featured on page, so that they could be bent to the required shape
My narrowest long cutter was 3 mm diameter, and I used this to form the grooves so that it required a 3 mm strip in the base of the repeat cutting jig
Cut the grooves across a piece of MDF wide enough to form both top and bottom trims. I spaced the grooves at 8mm, cutting them 9 mm deep. If you use a smaller diameter cutter, youuâ?ll need a long thin cutter that is strong enough
The glue covered trims can be bent gently around shape and then held in place with clamps and pins
The top is edged with a thin strip of maple planed down to 2 mm thick: proper edging cramps make it much easier to hold curved lippings like this in place
All the joints and remaining screw holes, along with the grooves in the trims are filled with Polyfilla and then sanded thoroughly
To fit the door I used a piece of 12 mm stock. Put a radius around the edge of the door to match that on the trims and top. A knob and magnetic catch finish the job
Although they are getting smaller and neater, central heating boilers could never be described as elegant, and then all the associated electrical and pipe work makes them look even worse. I was recently asked to box in a particularly unattractive one which was mounted at floor level, leaving the top fully exposed. The brief was to produce a design to cover up the boiler, but at the same time minimize the amount of space taken up in the already cramped room.
From a plumber's point of view it is important that the boiler can be serviced easily, and a close fitting cupboard makes this job a nightmare. The recommendation is to leave at least 6″ clearance all round the boiler, but the room was just not big enough for a cupboard of this size, so I settled on a much tighter design that was freestanding and could be easily removed. I did incorporate a small door so that the controls and filling loop could be accessed without moving the whole cupboard.
The answer came in the form of bendy MDF, which is available in 6 mm thick sheets. One face is cut with a series of regularly spaced fine grooves, resulting in a very flexible panel. This can be bent to quite a tight radius and seemed ideal for this purpose, although I must confess that I had never used it before, so the whole job was going to be a literal learning curve!
These bendy MDF panels are relatively cheap and easily available in 610mm widths from most of the big DIY stores. It is produced in much bigger sheets, but I was not able to source one in time, so had to use smaller sheets. In retrospect the job would have been much better if I could have formed the whole shape in one larger piece.
To form the curved panels, make a mould with pieces of 12 mm MDF, cutting out three equal rectangles to match the size of the cupboard footprint; cut them carefully as they will be used subsequently as top and bottom boards in the actual cupboard.
“I settled on a much tighter design that was freestanding and could be easily removed”
On a safety note, it is important to check that the boiler you intend covering is in fact suitable, as many of the older types require free air circulation in order to operate safely and it is extremely dangerous to restrict this air flow by enclosing them in a cupboard. Most modern boilers are fitted with a double flue, which draws in all the air it needs and exhausts the fumes through the same pipe. These boilers are classed as 'room sealed' and can be safely boxed in. Get qualified advice if you have any doubts.