Inserting a 'dutchman'

[chippy]

I thought I'd have a go at repairing a flaw in a nice wide piece of oak, using the technique of sinking in a 'bow-tie' or 'dutchman', to give it a more authentic, oldy worldy look. The flaw is not a knot, it is more of a deep scar, about 4cm long and about 4-5mm deep/wide.

To insert a dutchman, do I use the same material as I'm filling? I have a photo (I can try to load it) that shows a dutchman in a church door frame, of a very old church, that looks like its a completely different wood. Was this normal? I always assumed the filling part was the same material.

Also, if the flaw is all the way through, do I sink a dutchman on both sides? What would have been done in that situation in the past?

[engineerone]

i would think the question is what are you going to do with the wood, and do you need to do this repair???

if you are for instance going to use the piece as a table top, then it might be quite nice to insert a repair to add some extra interest, and in that case you might well use a different wood, or grain pattern.

if however it is an existing item, then again what are you seeking to achieve???

unless the flaw is deep, and will be seen in use, why repair where you don't need too???

paul

[jasonb]

Do you need a bow-tie shape dutchman, these are usually used at right angles to tie a split together. A contrasting timber is often used to make a feature of these.

If its just a repair then a diamond shape is more usual as this blends in better with the grain running the same way as the main board in the same wood, often seen where a cylinder lock has been removed from a door, one both sides.

Jason

[jonnyd]

For a high tech expensive powertool solution you could buy this setup

www.lamello.com/en/downloads/application-videos/wood-repair-system.html

click on play

jon

[9fingers]

One of the router bit suppliers does a dual size guide bush and cutter set for doing surface repair dutchmen. Trouble is I can't find which one it is at the moment.

Basically cut a template in ply or mdf. Attach/clamp the template to the surface to be repaired, fit the small bush and route out the whole of the damaged area.
Fit the template to the donor timber near the edge, fit the small collar, and rout out the profile of the patch. Pass the edge of the donor through the table saw to release the dutchman.
Ease the corners to the same radius as the cutter, glue and fit to the workpiece.
Classic bow-tie shapes look nice but in practice can be any shape to suit the job.

Bob

Edit: Found it! Trend do one here preview.tinyurl.com/6vjy96

[dom]

Jan 11, 2009 13:57:45 GMT 9fingers said:

One of the router bit suppliers does a dual size guide bush and cutter set for doing surface repair dutchmen. Trouble is I can't find which one it is at the moment

Trend

[9fingers]

Ah Thanks Dom.

Must remember to read the latest version of the thread before editing!! Doh!

Bob

[chippy]

Im using the timber for a roll top desk, the flaw will be about a third of the way in from one edge of the writing surface. I was thinking about leaving it, because it adds character, but Im concerned it might be weak in that area. I also thought about sinking in a rectangle of coloured leather but I would prefer to show off the wood. I like the way on older furniture that flaws are turned into interesting 'features'.

The line of the flaw is with the grain in fact it looks like a bigger version (much wider, deeper) of the one being repaired in the video posted earlier by jonnyd.

Given I havent done this before, I might go for a diamond pattern which is probably easier. I can try this out on some scrap first. Thanks for the info. Btw are any particular shapes of dutchman associated with English furniture? Before I route ahead on this, Id like to be consistent.

Also, should I apply a dutchman on both sides? or leave the underside as is (it wont be visible because a drawer is beneath it).

[jonnyd]

Could you rip the board down the line of the fault and then joint and glue the board back together.

jon

[engineerone]

basically you will be weakening the wood unecessarily if you
do it both sides. might be worth putting a strengthener across it, but other wise, you are reducing the actual thickness.

i am however with johnny. what about cutting it down and removing the flaw anyway???

you make another interesting point in that in most cases, the writing surface itself is protected, often by a skivver.

paul

[chippy]

I could do that too, decisions, decisions...

[engineerone]

it's a good exercise, but how often will you use it, and what would you feel if you have stuffed up the whole piece of wood.

find a piece of pine or some other waste scrap, and play around with that i.e try to replicate the flaw, and repair it and see how happy you are with the repair.

if you have a special piece of wood it is tempting to over complicate things, and delay actually making the piece you have in mind.

paul

[mrgrimsdale]

For a low-tech inexpensive hand tool solution, and a perfect result obtained very quickly wot I'd do is:
Cut out a little repair piece of whatever, to cover the mark, a straight sided rectangle (or triangle etc whatever fits), about 3/4" thick.
Lay this over the mark and draw around it.
Hack out a shallow 1/2" mortice, to the pencil marks but a bit tight.
Fit the repair piece by offering it up and trimming the edges with a block plane until it's a neat fit but with slightly tapered sides so it will tighten up when you tap it in.
Glue in the hole, tap in the repair piece until its a tight fit. It doesn't necessarily have to fit to the bottom of the hole as long as the sides are bit tapered. .
When the glue is dry trim it back to the surface with a block plane. Avoid trimming it back with a chisel as it might split and lift out too deep.
I suppose you could say that leaving it proud and trimming after the glue is dry is the secret of invisible mending, or neat finishing in many places, such as the ends of through tenons

[colincott]

Sorry jacob
On this one I would not do that, if you want it to stand out and it will if you put a square in it.
I call dutchman, butterflies and they are real easy to do as I have done lots of them with hand tools or a router.
The hardest bit is making a round it without it moving but they are a few ways a round this too.

the thing you need to do first is to make your butterflies with square sides to amke sure it is a good fit and to help stop it from moving, you can put some masking tape on the bottom of it.
Mark a round it and also mark with end is which, so that fitting it will be much easier.
You can then get your router if you dont want to do it by hand, router/drill most of the middle out but if you use a router you can then move it out very close to the line.
This will leave a little to chisel out, making sure you use a sharp chisel and should be able to do it in about 5 minutes or you can use the same way for a diamond shape.

One more tip, is to chisel a small chamfer on the bottom edge for the butterfly and this will help you get it down to the bottom of the hole.

Hope that is clear

[chippy]

Great inputs everybody.

I know it may sound like Im overcomplicating it when I could just rip and biscuit it. But this is one of those occasions where I have an excuse to learn a new skill. So I'll have a go at this (on some scrap). If the result is too tatty or it just proves too difficult I can always resort to Plan B.

[mrgrimsdale]

Jan 11, 2009 20:52:22 GMT colincott said:

Sorry jacob
On this one I would not do that, if you want it to stand out and it will if you put a square in it.
snip

Hi Colin
Er - whats the difference? We seem to be describing the same thing. It's something I do a lot with old joinery, usually to fill a hole made by old hardware fittings. I'd make two sides of the new hole and the infill piece go along the grain so that the join is invisible. This would leave a fine line across the grain at the ends which would be hard to see if the grain matches.
Is a 'dutchman' or 'butterfly' different?

PS just googled around. The difference seems to be that Colin is talking about repairing knots and natural defects which a diamond shape might fit best, but I'm talking about holes made for locks etc which start out rectangular and are best repaired with a rectangle - following the grain.

[colincott]

Jacob
I would use a dutchman when there is a split in the wood along the grain to help hold them together but if I am patching in an old lock.
I would not use a square as they do tend to stand out a lot more as you are going right a cross the grain.
Here is an old repair to a front door and you can see it was not a good one plus its square
Here is my one which was also done with old timber and as you can see it is not square a cross the grain and as I furniture restorer, I have seen what old repairs look like and the old ones that are not square a cross the grain always look much better if you can find them right away.
They tend to be harder to see.

[mrgrimsdale]

Well that's convincing! Actually what I do would not be as bad as your first one, but simpler than the second one. But most of my stuff is painted.

[colincott]

If ti is painted then it does not make a lot of difference that is until someone whats to strip it and then the square patches dont look so good plus it does not take that much longer to do a diamond one.
You dont have to go as far as I did in that one, making the sides not the same but it does help break up the patch to make it herder to see.

[dom]

Nice job Col.

[gazza]

Super repair Colin,
Impressive
Cheers,
Gazza.

[colincott]

Thanks but can get a lot harder when I have had to do the same with old surface and let it in flush with an old top.

[jonnyd]

Just wondering why these types of repairs are called dutchman anyone know?

jon

[chippy]

I wondered that too, I got this quote;

"What on Earth’s a Dutchman?
The answer, he found, goes back to the late seventeenth century, when the bourgeois Dutch were seen by the more raffish English as penny-pinching cheapskates, so much so, in fact, that they would walk down the street wearing trousers with patches on! OK? Now we know."

from this site www.fiskeandfreeman.com/acorns_1107.aspx

[engineerone]

some of you may, like me have chosen to watch some or all of the john adams series on saturdays about 5pm on channel 4.

last week, he was trying to negotiate a deal with the dutch.
at that time holland was a republic, 1776 etc. having overthrown the monarchy in the early part of that century i think not long after william of orange became english king during the glorious revolution of 1698. must check my history books.

so in those days i would think the whole protestantism and republicanism would have increased the make do and mend mentality, it is interesting to think though that the dutch were more successful traders internationally than we were.

so i can certainly imagine it is called a dutchman because it was first seen on dutch ships, when they nipped down the thames to destroy one of our fleets.

nice work colin, nice to know some of my similar work got your approval for a first set of efforts. ;D

paul