Thread: Coopered lid jewellery box: WIP

will be watching with interest

waiting to see the coopering jig

Looks like a good project.

As the staves were cut well over length, it's time to cut them down to just over the finished length of the panel. I set up an auxiliary fence to trim the first end off, then set a stop on the mitre gauge to cut them to length.
Cutting staves to length.jpg
The idea of the mitre gauge is to stop the blade catching an off cut and turning it into a missile. However, if you don't remove the offcuts, they can still get pushed onto the blade, with exciting results. This reminds me why I always wear a face mask and don't stand in line with the blade.
Offcuts.jpg
After the staves are cut to length, they are placed in order and taped together with stretched masking tape on the outside. The masking tape acts as a light clamp to hold the staves together. I then put them in the jig and coat the inside with wax to stop the glue squeeze-out sticking. I also put wax on parts of the jig that are likely to get glue on them.
Staves taped.jpg
For this type of work, I like to use a thick epoxy, which allows a longer gluing tome than PVA, and is easier to tint.
The aim is to have an invisible glue line, so it's important to have accurate joins. No matter how good a colour match you get with the glue, it will be visible if it's too thick. To match this timber, I used terra rossa, yellow ochre and burnt umber pigments.
Glue-up gear.jpg
A light coat of glue is applied to the joining faces of the staves, and they are closed up and put in the jig. To tighten them up, I use wedges pushed together. Usually, the small clamps are not necessary, but I was a bit profligate with the wax, so friction alone doesn't hold them.
Glue.jpg
Glue-up 2.jpg
Glue-up 1.jpg

Hi Alex

I am curious - did you taper the staves to join flush along the sides at an angle, or are you butting them at an angle and filling the gap with tinted epoxy?

I have made a couple of coopered topped boxes, and each had staves that were sawn to butt at the correct angle, then planed smooth inside-and-out. It would be interesting if there is another method.

EDIT: Rereading your initial post I see you "bevelled" the staves. How did you do this? I am sure readers want that information.

Regards from Perth

Derek

Hi Derek. I've used the same method as you - bevelled the sides at the correct angle, from the spreadsheet. I didn't plane them, as I believe my saw is set up accurately enough not to leave a visible glue line. Time will tell!

After the glue has set, I'll plane the outside smooth. For this box, I'll leave the facets on the inside, but in the past, where I've needed a smooth, cylindrical inside, I've used a curved scraper and a wooden cylinder with sandpaper wrapped around it, spinning in the lathe.

To bevel the staves, I first cut them slightly oversize. The TS blade is set at the correct angle and with the fence on the left side of the blade, bevel the first edge. This leaves the wide (outer) face of the staff uppermost. Then turn the staves end for end - outer face still uppermost - and adjust the fence so that the width of the staves is correct, and bevel the second side. When cutting the staves and bevelling them, I use magnetic featherboards on the feed into and out of the blade, to avoid any inaccuracy.

Hello Alex, another of your beauties coming up I can tell.

What make of blade and spec do you use Alex to produce such cuts on the table saw?

Originally Posted by AlexS

Hi Derek. I've used the same method as you - bevelled the sides at the correct angle, from the spreadsheet. I didn't plane them, as I believe my saw is set up accurately enough not to leave a visible glue line. Time will tell!

After the glue has set, I'll plane the outside smooth. For this box, I'll leave the facets on the inside, but in the past, where I've needed a smooth, cylindrical inside, I've used a curved scraper and a wooden cylinder with sandpaper wrapped around it, spinning in the lathe.

To bevel the staves, I first cut them slightly oversize. The TS blade is set at the correct angle and with the fence on the left side of the blade, bevel the first edge. This leaves the wide (outer) face of the staff uppermost. Then turn the staves end for end - outer face still uppermost - and adjust the fence so that the width of the staves is correct, and bevel the second side. When cutting the staves and bevelling them, I use magnetic featherboards on the feed into and out of the blade, to avoid any inaccuracy.

Hi Alex

Yep, I did mine that way.

I've long considered making a jig - like yours below - to hold the staves as the glue dries ..



Instead, I add glue to each piece, push them together, then use packing tape to hold them tightly ...



... and then stretch them into the curve ...



The bevelled sides ensure that the angles are correct, and the tape ensures a tight join (this started out for a chest door, then became the side to a side table) ..



Just another way.

Regards from Perth

Derek

After 4-5 hours depending on temperature, the glue will have a hard rubbery texture, so it's a good time to remove the panel from the jig and strip off the glue. The wax makes this an easy job.

Now it's time to round the panel. The first step is to plane the corners off the facets, leaving double the number of facets. Plane each corner until the 'old' and 'new' facets are all about the same width. Then, plane a few strokes to remove the corners again. At this stage, the panel will be approaching round, but will still feel 'lumpy'. It is now ready to finish rounding using a patternmaker's rasp, file and sandpaper.
glue removed.jpg
I used a fine patternmaker's rasp, working diagonally, to remove the remaining corners and bring the panel to round. Work lightly, not applying much force to the rasp, and remove just enough wood to round the corners. With each stroke, lower the hand on the handle as you push the rasp through, and move the rasp to the side as you make each stroke. Go over the whole panel so that you can see light rasp marks all over the panel. Then, repeat the process with a bastard cut file until the rasp marks are removed. At this stage, you may still be able to see some file marks.
Rasped & filed round.jpg
Next, I used 80 grit sandpaper on a hard block, sanding along the grain, to remove all the file marks. Sand the full length of the panel until all the rasp marks are gone. Feel the panel for any uneven spots, and inspect it carefully for any tool marks.

The piece should now feel round, with no high spots. Now, go over the panel very lightly with a card scraper. Work mainly along the grain, but if you can still see any file marks, you may want to work diagonally as well. When you're happy with the shape, with no flat spots or tool marks, sand it to the desired finish. I worked from 180 grit up to 800 grit.
Sanded.jpg
Clean up the dust by blowing with a compressor if you have one,then washing liberally with metholated spirits and paper towels. When clean and dry, I applied a coat of shellac, and after this was dry, I sanded it lightly with 800 grit and cleaned up with white spirits.
Shellacked.jpg

I'm enjoying the WIP Alex. Good work

Watching, learning

Originally Posted by groeneaj

I'm enjoying the WIP Alex. Good work

What make of blade and spec do you use Alex to produce such cuts on the table saw?

It's an HBS (Henry Bros.) 10" 60 teeth blade. I think the important thing is to have a sharp blade that is parallel to the fence.

I trimmed the lid panel to length on the TS, then had to shape the panel ends to fit the grooves (yet to be cut) in the box ends. First, I rounded the facets on the inside of the panel by hand, then modified the glue-up jig to make a routing jig to cut a curved slot in the panel.
Trimmed panel ends.jpg
Trimming jig.jpg

I also resawed, dressed and marked to length the box sides. Today, I'll sand them, cut to length and mark out the dovetails.