Sanding Floor - filling cracks with sawdust and glue
 

Hi All,

I'm sanding my living and dining room floors this weekend. I sanded a
similar floor in my last house a few years ago, and was happy with the
result but regretted not filling the gaps between the tounge and
groove boards. This time I'm planning to fill them with a mixture of
sawdust and glue - as suggested in various postings and the faq.

I have a couple of questions, that I'm hoping someone who has actually
tried this might be able to answer :

- What glue would it be best to use? I'm thinking either pva or wood
glue. If pva, could the varnish make it turn white again? (I'm
planning to use a water based varnish - Ronseal Diamond Hard). How
about 'waterproof' pva? (saw it in Wickes next to the normal pva).
Would wood glue be better? (does that dry clear?)

- I'm planning to sand down to fine grade, then fill the gaps leaving
the filling proud of the gaps, then sand with fine grade again to make
everything level. Anything wrong with this plan? I won't need to go
back to medium grade again to level off the sawdust + glue will I?

Any other words of wisdom anyone who has tried this can offer would be
appreciated!

Thanks in advance,
Dave

On 13 Nov 2004 01:33:16 -0800, (Dave Young) wrote:

This time I'm planning to fill them with a mixture of
sawdust and glue

I don't like this approach - although I've used it on plenty of
floors. It works fine at first, but it shrinks over time and gaps
open up. If your gaps are small to begin with, then it might work for
you.

Screwfix offer a slightly flexible floorboard sealer in mastic gun
cartridges. I might use this sometime and see if it's any better.

- What glue would it be best to use?

Cheap PVA - go to the builder's merchant and buy a gallon for almost
nothing. It's also a perfectly usable wood glue. Don't let the frost
at it though.

(I'm planning to use a water based varnish - Ronseal Diamond Hard).

Works fine over the sawdust filler.

Personally I always use acid-cure formaldehydes on floors (Rustin's
Floorcoat), but Diamond Hard should be OK.


- I'm planning to sand down to fine grade, then fill the gaps leaving
the filling proud of the gaps, then sand with fine grade again to make
everything level. Anything wrong with this plan?

Two things:

You can't sand the gaps until the sawdust has dried, and this takes
ages. If you're doing more than one room you can do it by pipelining
and filling the next room the day before you need to finish sand it.
Otherwise it will slow you down considerably, just in drying time.

Secondly, you don't need it level - it'll shrink anyway. The main
reason for running the sander over it again is to clean up the boards
alongside, if there's any spillage.

--
Smert' spamionam

"Andy Dingley" wrote in message
...
On 13 Nov 2004 01:33:16 -0800, (Dave Young) wrote:

This time I'm planning to fill them with a mixture of
sawdust and glue

I don't like this approach - although I've used it on plenty of
floors. It works fine at first, but it shrinks over time and gaps
open up. If your gaps are small to begin with, then it might work for
you.

Screwfix offer a slightly flexible floorboard sealer in mastic gun
cartridges. I might use this sometime and see if it's any better.

- What glue would it be best to use?

Cheap PVA - go to the builder's merchant and buy a gallon for almost
nothing. It's also a perfectly usable wood glue. Don't let the frost
at it though.

(I'm planning to use a water based varnish - Ronseal Diamond Hard).

Works fine over the sawdust filler.

Personally I always use acid-cure formaldehydes on floors (Rustin's
Floorcoat), but Diamond Hard should be OK.


- I'm planning to sand down to fine grade, then fill the gaps leaving
the filling proud of the gaps, then sand with fine grade again to make
everything level. Anything wrong with this plan?

Two things:

You can't sand the gaps until the sawdust has dried, and this takes
ages. If you're doing more than one room you can do it by pipelining
and filling the next room the day before you need to finish sand it.
Otherwise it will slow you down considerably, just in drying time.

Secondly, you don't need it level - it'll shrink anyway. The main
reason for running the sander over it again is to clean up the boards
alongside, if there's any spillage.

--
Smert' spamionam
Why not cork (this may not be the correct spelling) the floors as they do on
boats looks neat and does not shrink otherwise one would be in trouble at
sea. Perhaps a chandlers yard may give advice?
MikeS

On Sat, 13 Nov 2004 14:57:05 +0000, Andy Dingley
wrote:


Personally I always use acid-cure formaldehydes on floors (Rustin's
Floorcoat), but Diamond Hard should be OK.


Hi,

BTW is this stuff UV resistant?

cheers,
Pete.

On Sat, 13 Nov 2004 22:33:11 +0000, Pete C
wrote:

BTW is this stuff UV resistant?

Yes.

I think it's a bit iffy on gamma radiation, but it's hard against most
other hazards. Stinks when you put it down, but it's a damn good
product in service.


(Actually it's not perfectly resistant - if you want real heat
resistance too, they do a special version for that).

IMO *saw*dust and glue looks bloody awful. If you have dust from the sander,
it looks marginally better but still not remotely similar to the boards
themselves.
I would lift and re-fix wherever possible, or fill with 2mm or 3 mm strips
if you have a sawbench handy (and the gaps are reasonably uniform), or match
a proprietary filler to the finished surface (not the bare wood) as a last
resort.

On Sun, 14 Nov 2004 12:46:00 -0000, "stuart noble"
wrote:

IMO *saw*dust and glue looks bloody awful.

Agreed, but then I've never needed to use it.

If you have dust from the sander,

Which is a fair assumption, although it does introduce the scheduling
problem.

it looks marginally better but still not remotely similar to the boards
themselves.

Is that a problem ? You're not trying to make the gaps vanish, you're
trying to stop the draught and make it look tidy. Some minor contrast
seems perfectly OK, IMHO.

I've not been a fan of strips, because I've always had tapered gaps.
If they were that even, you could shove the boards up and close the
lot out.

--
Smert' spamionam

In message , Andy Dingley
writes
On 13 Nov 2004 01:33:16 -0800, (Dave Young) wrote:

This time I'm planning to fill them with a mixture of
sawdust and glue

I don't like this approach - although I've used it on plenty of
floors. It works fine at first, but it shrinks over time and gaps
open up. If your gaps are small to begin with, then it might work for
you.

Screwfix offer a slightly flexible floorboard sealer in mastic gun
cartridges. I might use this sometime and see if it's any better.

- What glue would it be best to use?

Cheap PVA - go to the builder's merchant and buy a gallon for almost
nothing. It's also a perfectly usable wood glue. Don't let the frost
at it though.

I've found it's not as good as bespoke PVA wood glue, the set result is
far less flexible / more brittle; for those who remember it more like
Cascamite than bespoke PVA wood glue.


--
bof at bof dot me dot uk