Thread: Painting Corbells

I'd just do the lot in MDF. Rather than laminating two 16mm pieces for the corbels, why not use 32mm MDF and save running the risk of a hair line crack down the face of the corbels?
You will need to prime the "end grain" well, as its like a sponge. Comes up well with two pack or auto paint.

Originally Posted by rustynail

I'd just do the lot in MDF. Rather than laminating two 16mm pieces for the corbels, why not use 32mm MDF and save running the risk of a hair line crack down the face of the corbels?
You will need to prime the "end grain" well, as its like a sponge. Comes up well with two pack or auto paint.

Not sure what you mean about laminating two 16 mm MDF boards. The corbels are about 128 mm wide, so it would mean laminating eight 16 mm or four 32 mm borads. I wonder about how much the mass would expand over time and produce the hairline cracks that you mention.

I agree with rustynail, 32mm will stop the hairline crack that you will get with laminating two pieces together. I would also mitre the joins, if you simply butt join the mdf, hairline cracks will appear there to. You can also get hm (heat and moisture) mdf that would be better in this situation. Have you got yourself a ready made rangehood that the shroud its fitting over?

I agree re mitres. Standard practice in cabinetmaking/shopfitting/joinery (or if not pos you laminate over with white liner and sand ready for paint). Always conceal end grain for two-pack...more importantly glue lines. Glues with any degree of flexibility will cause cracking. I'd go solid pine or similar for the corbels and blade fill any end grain with a quality filler.

I hope your a professional finisher if you plan to spray two-pack yourself. Anything but easy to get a flawless finish.

Craig.

If the corbels are going to be that wide, I would be going to solid timber and looking for something a bit more stable than pine ie cedar .

Originally Posted by zelk

I am making a kitchen range hood canopy as shown in the picture. The canopy in the picture is roughly to scale cardboard copy. I plan to make the structure using MDF and paint it in white two pack poly. I would like to know what is the best way to make the corbels, shown under the canopy, shaping 1. a lamination of sheets of 16 mm MDF or 2. lamination of finger jointed pine? As the curved end grain would be seen face on, what material would give the best painted finish? Are there other things I should consider in this project?

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Hi Zelk

are the "hot plates" gas or electric?

do you know what the required minimum vertical and horizontal clearance is between your chosen stove top and a range hood or other flamable materials like curtains?

I'm not sure that I would be using MDF or even wood, there's usually too much steam above a stove

To answer all questions.

The shroud is in MR MDF and I have butt jointed the pieces. The end grain projects sideways and I have sealed them with PVA glue. The shroud will be sealed and painted with acrylic wall paint.

The skirt is also in MR MDF, however, I have used melamine coated MDF on the underside. The trimmings are in finger jointed pine. Again the pieces are butt jointed with a small section of end grain facing to the side.

All butt jointing, with the skirt, involved the use of the the Festool Domino.

The skirt is overall 1500mm wide and sits 750 mm over a gas hob. The gas hob is 800 mm wide, so I think the heat will have minimal affect on the corbels.

The skirt and corbels will be painted in two pack poly and this will be outsourced to a professional painter.

Oh, by the way, the rangehood has been fitted and ducted to the outside. The shroud and the skirt are merely covers fitted to the structure supporting the rangehood.
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