Am I doing this right?

[RigidRaider]

I am remodelling our downstairs cloakroom and adding a small Laufen urinal with a lid, as we have a 7 year old son with terrible aim. The urinal has a fly in the glaze as a target! This will also benefit me and my male friends.

I have sorted the plumbing and have added a low-cost push button for the flush. To hide all this I have studded the wall with timber about 30mm deep and have decided not to plasterboard and skim, but instead have bought a huge sheet of a French-made 19mm chipboard with a plastic layer laminated on both sides. I plan to fix this to the studding with screws, which I will hide with little plastic covers. The idea is to make access for any future maintenance easier.

I only have two concerns:

1 - My son isn't strong enough yet to work the button!

2 - The edges of the board will not cut finely and will look scruffy. I could silicon I suppose, as that's not too permanent. I wanted to use the same superb Mermaid shower board we used in our shower but.. the cost!

Any comments or suggestions?

 

[Scrit]

Take it down to the local kitchen fitter's and ask them to cut it for you on their panel saw? Sounds like it could benefit from being cut on a decent saw with a sliding table and a scoring blade. I find I can cut most things on my panel saw with a good edge finish. BTW what is this board called? (So I can look up what the material is)

Scrit

 

[RigidRaider]

Thanks. The board is Polyrey. French. 19mm with a thin laminate on each side. I have a circular saw with a fine blade but even that rips a bit. I might have to resort to hand-sawing.

 

[JohnD]

The urinal has a fly in the glaze as a target!

English urinals used to have a bee under the glaze as the target. This was a classical joke by the Victorian designer, the latin for a bee being "apis."

 

[splinter]

answers to you're questions:-

1) He soon will be.but if he is like my son he won't be arsed to push the button anyway.
2)Could you not clean the edges up with a router/planer

 

[RigidRaider]

Yes, I will probably have to do some planing anyway to get a good fit with the walls each side - I'm doing the entire end wall. I am also going to seal the exposed chipboard with clear varnish to prevent moisture entering and to keep it all crisp.

 

[Scrit]

Thanks. The board is Polyrey. French. 19mm with a thin laminate on each side. I have a circular saw with a fine blade but even that rips a bit. I might have to resort to hand-sawing.

The stuff you are talking about is MFC (melamine-faced chipboard) and you'll probably struggle to get a decent cut on it with a handsaw. I certainly wouldn't fancy trying to hand rip an 8 foot long sheet - life is too short! To cut it cleanly get yourself a decent fine-tooth sawblade for your circular saw as your saw probably has something like a 12 to 16 tooth rip blade on it (useless for any sheet material). What you need is an ATB (alternative top bevel) blade for it. Post the size of the blade and I might even be able to recommend a blade and the tooth count/pattern - although Freud make very good replacement blades for portable saws. If you are in Blackburn try Little Sheffield, or in Liverpool you try Taylors. You'll also need a straight edge, such as a good straight piece of Contiplas shelving to run the saw against and at least as long as your sheet as well as a couple of G-clamps or quick acting clamps. If you are struggling for a work surface, expanded polystyrene builders insulation sheets make excellent sacrificial cutting boards for breaking down big sheets

Make all your cuts from the same side, running the saw against the straight edge/batten which you have clamped onto the MFC sheet. The visible side may well look a bit raggy, but the other side should have a good clean cut providing the blade was sharp and you have run the saw against a straight edge. Do it freehand or using the Mickey Mouse flexible rip fence most small portable saws have and it'll be less than perfect in all probability. If you need to trim ot make cut-outs either do these with a jigsaw and fine upcut blade from the same side or use a down cut blade and work from the finish side - in both cases turn the orbital motion off. The jigger will be slow but you'll get a better cut. Use a fresh blade.

For use in a potentially humid environment I'd suggest masking off either side of the edge then applying a thin coating of clear or white silicone (the fungicidal variety),. This will work better than trying to varnish the edges. Chipboard is like blotting paper and varnish tends to craze with age and let water through - so not the best combination, methinks.

Scrit

 

[RigidRaider]

Thanks. I wouldn't have thought of setting up a straight edge to guide the saw. I'd have drawn a line then tried to follow it, which is difficult as you know. The (borrowed) saw had a terrible blunt ripping blade so my retired plumber neighbour shambled off to his shed and came back with a selection of blades in the right size, unused, in original 1970s packaging! They are non-metric sized but perfect! I fitted a fine-toothed blade and it cuts well though I will experiment to find which side it leaves best - the in-cutting or the out-cutting. I have already halved the sheet on blocks on the ground, just to enable me to handle the damned thing! Will also do cutouts etc with holesaw and jigsaw though these will be hidden behind the porcelain so don't need to be too perfect. Finally thanks for your advice on sealing the edge. It shouldn't get wet at all but chipboard is fragile and once it gets damaged or damp becomes even more prone to breaking up.

 

[Scrit]

In that case a few final, if obvious, tips. If you are cutting through from the finish face with your jigsaw protect the surface of the MFC with some 2in masking tape and lay out your cutting marks on that - much easier to mark than melamine and the tape will stop the base of the jigsaw marking the face of the melamine. Secondly drill a hole in the middle of any cut-out (or more than one) and start the jigsaw from there. I have mastered the knack of plunge cutting with a jigsaw, but it can be a bit dangerous for novices and if it goes wrong you'll mark the workpiece, or worse still injure yourself. If the cut-out is large tape over the joint with masking tape to support the scrap as you complete the cut. That way you won't risk having the scrap break away and take some of the good surface with it.

Maybe obvious, maybe not

Scrit

 

[RigidRaider]

Fantastic! Thanks for your help.