Refurbishing reclaimed wooden floor

[johnny2007]

New projects for a neighbour.
As you can see from the pictures the tongues on the vertical joints are broken.
Would you use one or 2 biscuits to join them?
Maybe 2 it's a bit over the top, but glad to hear from you.
The horizontal tongues are fine, although I have to remove all the old glue (already built a jig to do that with a router for tongues and grooves).
Thanks

 

[Deleted member 174758]

I think what you need to watch out for with biscuits is that they are specifically designed to be slightly loose when fitted, but then to swell and lock the joint, so they (i) should always be used with a water-based glue and (ii) the shape of the biscuits will invariably telegraph through material for a few days after glueing until the excess moisture migrates away from the joint, possibly longer with sealed materials such as flooring.

On those occasions that I've done flooring repairs I've tried to use a glued-in loose tongue (basically a rip of plywood) with a water-resistant glue rather than biscuits, mainly because I feel it makes for a stronger joint. In the absence of being able to do that I think I'd go with multiple (smaller) biscuits and a D3 PVA.

 

[johnny2007]

Thanks.
I thought about using plywood rather than biscuits, but i only have 12mm atm and I didn't want to get into even more dust.
But as you mentioned that, I think I go with it.

 

[Deleted member 174758]

4mm plywood?

 

[johnny2007]

4mm plywood?

Not readily available, at least around here.
I've got to use the router, so I just mill the 12mm to 4mm and cut strips out of it.
Thanks