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Making Your Own Wood Filler

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Making Your Own Wood Filler

#1

Making Your Own Wood Filler

Tom Colligan


>In making a blanket chest with dovetails I've got some gaps. They are not big enough to fit wedge of end grain in but nevertheless need to be filled. I've saved enough saw dust from the Jatoba and the first coat of finish will be BLO in order to 'pop the grain'.

But what would be the best liquid I could use in mixing the sawdust? I fear using BLO will take too long for the filler to dry and firm up. If I use a glue I'm afraid nothing will penetrate it but I may be wrong on that. TIA, Tom.

Re: Making Your Own Wood Filler

#2

Re: Making Your Own Wood Filler

Thom D


>The problem with wood filler, even of the same material, is that it rarely looks anything like the parent material when wetted. There are exceptions and the key to this kind of work is to run your own test samples to see where you stand.

If your cracks are trivial hairline, then the easiest method is to lightly sand with the finest possible paper, that will fill the cracks with surrounding wood. Then French polish with CA glue. That is the hidingest method that uses dust.

Amazingly even some fairly major cracks can be completely hidden simply by filing the last little bit of the pin projection. This will hide playing card sized gaps flawlessly. You just leave the ends a little proud an take them down to level with a mill bastard file, and the gaps disappear. You will learn that the strokes need to be made so as to close the gaps not open them. This is basically a method Krenov taught.

Another method involves sawing the gap open a uniform width of the saw, and splicing in a triangle of material from the same batch of wood with the correct grain orientation. This is the method in Frid's books and videos.

Final method is faux finishing. Even though I know nothing about this method, I can paint in details that make maters better if not perfect. Just fool around, most of the damage can be reversed.

Re: Making Your Own Wood Filler

#3

I'm confused

bill tindall


>The patch is driven in at about 45 degree angle to the edge so that a long grain(hence strong) taper piece can be used. It can be tapered to zero and hence will start in any crack worth filling. If crack is too small for this approach it is too small to fret over. Of course I have not had any personal need or experience using this technique(and if you believe that......), but I have heard it will work.

Re: Making Your Own Wood Filler

#4

Filling gaps

Derek Cohen (in Perth, Australia)


>Are the tails raised a little above the pins? If so, simply spread the end grain into the gaps with a hammer, then plane it flat.

Regards from Perth

Derek

Re: Making Your Own Wood Filler

#5

Good idea

jim reed @ tallahassee


>that's a sharp idea. If the space is too large, just cut some long splinters and ram them home. A plane set on coarse will pull a nice shaving to use. Glue it in place and then chisel smoothe. Gotcha end grain going on and everything. Hard to see after finishing. Good luck.

Re: Making Your Own Wood Filler

#6

Hide glue...

John in New Mexico


>I've had good luck using hide glue. Never could figure out why I always heard of mixing dust with glue until I tried using hide instead of PVA. I've never tried it on endgrain though so you should make up a test of some sort to see if the results are as expected.

That said, from what you describe, I think I'd use Derek's method first.

John

Re: Making Your Own Wood Filler

#7

Re: Use the BLO

Dave Mount


>Depending on how open grained the wood is and whether a plane is the final finish, you can do it as part of your finishing with BLO. Just take some fine sandpaper and apply the BLO with it. Rub a little with the sandpaper to work up a slurry and push it into the cracks, then wipe off the excess slurry. The BLO acts as a binder and keeps the slurry secure in the crack as the piece dries. Finish the rest of the piece at the same time.

The dangers here are that with open grained woods, the slurry will fill the pores and change the look of the wood in the areas where you do this. The second issue is that if the final surface is planed and not sanded, sanding one area may subtly change the surface where you do the sanding.

If you don't want to do the filling in the finishing step for one or more of the reasons above, you can still use the BLO as binder to make a "putty" out of your wood dust. Just be careful not to spread it around too much if you have open grained wood. Using the same finish as you intend to use (BLO) as a binder will make it unnecessary to clean up the area around the fill with anything more than a wipe of a rag.

If these dovetails join two contrasting woods, I'd recommend using the darker wood to do the filling, but you need to watch that you don't get too much of the fill contaminating the lighter wood. If you do, a couple strokes of a plane afterward should clean up any surface contamination.

The pic below shows a drawer with a fill where I overcut the baseline on the drawer side between the two tails. In this case I filled with the birch dust from the drawer side because the birch was more open grained than the cherry. However, using the lighter wood made the fill more obvious; you can see it as a light line at the base of the middle pin. It was something of a lazy fix that could have been much less obvious if I'd put more work into the patch.

My $0.02,

Dave


img

Re: Making Your Own Wood Filler

#8

Bishoping

david charlesworth


>Derek,

Hammering the pins is known as "bishoping" in UK.

Very useful, but frowned upon in serious circles ;-)

What the h--k it has to do with Bishops, I am not sure!

David Charlesworth

Re: Making Your Own Wood Filler

#9

Re: Making Your Own Wood Filler

Dan Clermont in Burnaby


>Hi Tom

If the gaps were too small for a wedge I would leave them as a reminder of where your skills were today. You could hammer the joint as recommended by Derek although I have never tried this and agree with David that it is frowned up in serious circles.

I have never filled any dovetail gaps and use them as a reminder to take my time or practice my cuts before doing the real deal. My wife is the one who comments how much better my dovetails are now compared to my first attempts

Dan Clermont

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