End grain tongue and groove for floorboards

[andrewm]

My project for next weekend is to lay a new tongue and groove hardwood floor in the hall. To allow for a recessed mat one section will not go right to the door and what is more the end will be angled. I want to put an additional strip across this end and since the rest of the boards are tongue and groove was going to put a tongue on the angled end to attach a narrow board to.

This means that I am going to have to cut and angled tongue on the end grain and probably put a corresponding groove in a narrow board. Because of the length of the boards I don’t think this is possible on the ‘Rat.

Now, the boards are 20mm thick so too thick for a standard tongue and groove router set and besides the groove is 6mm which seems to be a non-standard size. As I see it I can cut the tongue using a bearing guided rebate cutter and the groove using a bearing guided slot cutter although I may need to change the beating to get the right depth. If I butt a piece of scrap against the board I can avoid breakout.

As far as I can see this should work but is there anything that I have forgotten? Or, am I trying to make things to complicated and should I forget matching the tongue and grove and just use biscuits.

Any advice appreciated.

Andrew

 

[Andy Pullen]

Cut a groove in both and use a loose tongue made of ply or suchlike. The only issue i would have is the cross grain movement and i would maybe stick it into the endgrain of the boards with clear silicon rather than glue because it will be more likely to give a bit with the movement of the boards shrinking and expanding with the seasons. Let the timber lay in its room to acclimatise for a few weeks aswell to minimise this.

 

[andrewm]

Cut a groove in both and use a loose tongue made of ply or suchlike. The only issue i would have is the cross grain movement and i would maybe stick it into the endgrain of the boards with clear silicon rather than glue because it will be more likely to give a bit with the movement of the boards shrinking and expanding with the seasons. Let the timber lay in its room to acclimatise for a few weeks aswell to minimise this.

That's a good idea. I hadn't thought about loose tongues. Each board will be secret nailed to the joist through its tongue so I am not expecting movement to be a major problem although if I am going the loose tongue route then no reason I shouldn't use silicon.

Oh, and the boards has been acclimatising for rather more than a week or two on account of having to get around to all the other things that need to be done before the new floor goes down.

Andrew

 

[Andy Pullen]

If they are nailed to joists there is probably no need to stick them at all, just push up tight and nail and they shouldn't go anywhere. I had visions of you laying boards over a concrete ground floor when i first replied. Cheers andy.

 

[OJ]

I'd be tempted to try and trim the heads in situ to get a tight joint all along the trimmer. You could use a circular saw and straight edge to make a half lap, one full depth cut and another at half depth. Finish the cuts at the ends by hand. The trimmer ends up as an upside down L shape. The timber will not shrink along its length, so glue the whole lot up. O

 

[RogerS]

When I had a similar problem, I used my biscuit jointer and biscuits...worked fine.

 

[andrewm]

Well I'm going with Andy's suggestion of using a loose tongue for this. I've just ordered a suitable bearing guided slot cutter router bit from Wealden since they seem to be well recommended on these forums.

Since I've never used one of these 'assemble them yourself' type cutters is there any technique to stop the actual cutter rotating on the shaft or is it just down to tightening the nut fully and relying on the direction of cut to keep the nut tight.

Andrew

 

[Colin C]

Since I've never used one of these 'assemble them yourself' type cutters is there any technique to stop the actual cutter rotating on the shaft or is it just down to tightening the nut fully and relying on the direction of cut to keep the nut tight.

Andrew

Hi Andrew

Just tightening it down and you should be ok but let me add one small thing, that is to make sure you put the cutter in the right way as it is easy to put in the wrong way ( I know having done it myself :roll: ).

Not trying to teach you to suck eggs