A Bed

[SketchUp Guru]

I drew this up this morning mostly to practice my SketchUp skills. It's based on a design from 1907. What do you think?

The 3/4-inch-square spindles are to be mortised into the rails. How would you cut the mortises in the top rails so that it was relatively fast and accurate? I have some ideas but I thought this might get a bit of discussion going.

By the way, the bed isn't short. It's just really wide. :lol:

 

[xy mosian]

Hi Dave, You could mortice the top rails before cutting the curve from the blank. If sizes allow of course. That way you have the appropriate flat square faces to refer to either for hand or machine work.

xy

 

[SketchUp Guru]

Yes, you could do that. I was thinking of steam bending the rails rather than sawing them out.

This is just for discussion mostly. I'm not sure I'd get this built anyway.

I had a thought of cutting a 3/4 inch wide by 1/2 inch deep groove down the length and then gluing in blocks between the spindles. Maybe a guy would use some plastic blocks as spacers--stand ins for the spindles--so they wouldn't get glued into the holes. After the glue is dry they could be trimmed close to flush with the bandsaw and really flush with a router and hand work. Just ideas though.

 

[barkwindjammer]

I think Steve Maskery has some kind of router base on roller bearings, with an angular adjustment and a plumb bob attachment on it, if he hasn't then what the hell has he been doing ?

 

[xy mosian]

UMM! Steam bending Eh?
If the blocks are glued in before steaming, obviously they could fall out if the glue failed.
On the other hand, glueing blocks in after bending. A regular block would naturally sit with groove-side faces on a radial line, ie. not in line with the spindles. Now one side would perhaps not matter as the angle would generate a small void in the assembled joint. The other side could be trimmed either before, or after, fitting into the groove. Or the top of the spindle could be trimmed slightly to fit. That trim would ideally be different on each spindle, in pairs of course. Personally I would decide on the trim for the outer spindles, the largest, and make them all the same.

What fun. Of course the chair bodgers would look at it sideways, take a guess, and probably get it right morticing by hand.

xy

 

[SketchUp Guru]

I think I'll have to sketch out my block idea to make it clearer. Will do when I get home.

 

[xy mosian]

Just had another thought. Oh No! I wonder what would happen if the mortices were cut before bending the rail? That surely would give a result just like gleing un-trimmed blocks into a groove. 'Twould save a lot of work.

xy

 

[SketchUp Guru]

I don't think so because the mortises would then all point at the center of the arc rather than straight down.

 

[xy mosian]

Isn't that the same as simple blocks glued into a groove after bending? The effect I was trying to describe in an earlier post.
xy

 

[xy mosian]

A last thought before I switch off.
Bend the rail, groove before or after.
Prepare a 'comb' the teeth of which will form the filling between the mortices. Shape the free end, end of teeth, of the comb to the curve of the groove bottom.
Glue into the groove.
When dry slice off the body of the comb.
I think that should result in correctly shaped mortices with the sides aligned to the spindles.

I'll sleep on it now and attempt a Sketchup in the morning, or at least an old fashioned sketch.

Night.
xy

 

[SketchUp Guru]

Sleep well.

Here's what I was getting at.



The white things are the spacers standing in for the spindles. The brown is a section of the rail with the groove cut in it. The blocks go in so their sides are parallel to the spacers. There would be tiny voids above the blocks but they'd be insignificant. They could be filled with thickened epoxy, too. After the blocks are glued in, the spacers can be removed and the blocks trimmed flush.

If you made a comb and bent it into position, you'd have the same problem as bending the rail with mortises already in it. Here I've drawn the comb straight and then bent it to fit the rail. The lines are perpendicular to the bottoms of the notches. You can see they appear to radiate outward in the bent comb.

 

[barkwindjammer]

start with a rectangular piece, cut the 'lower' curve of the finished piece on one side of the rectangular piece, so you have one side of the original rectangle which is flat(straight) with the opposite face curved, with the flat/straight face you have a reference edge, this flat/straight edge would be on the bench with the curve facing up-run it through a bench morticer, when all the mortices are cut then cut the flat/straight edge to follow the profile of the first curve edge with a bandsaw-et viola

 

[SketchUp Guru]

That makes sense for sawn rails. Good to remember not to cut away the reference face too early.

 

[xy mosian]

Wiping t he sleep from my eyes. Yes I agree Dave, with your drawn arrangement the blocks would be out of line. The spacer idea would surely work well although a bit fiddly. My suggestion was a comb with a stouter back which would not bend. The curved end of the comb cut to shape. thereby keeping the sides of the blocks in alignment. I'll fire up Sketchup to try and draw it.

xy

 

[SketchUp Guru]

I see. I'll be interested in seeing your drawing.

By the way, the top arc is 3" deep and the thickness of the top rail is 1-14".

 

[xy mosian]

Ok! here is the sketch. The more I think about it, although my suggestion would give aligned blocks, there is potential for movement as they are glued in. Still ..

Hope this makes my thoughts clearer.

xy

 

[SketchUp Guru]

I see. Essentially the blocks I am proposing would be the tips of the comb teeth. That would make aligning them easy. If the comb board is wide enough, you could get both rails taken care of with a single comb. It would be rather wasteful of wood, though. I was thinking of making a couple of pieces 3/4" thick by 1 or 1-1/4" wide and then cutting them into 1" long blocks which is the spacing between spindles.

Edit to add: You could still use spacers between the comb teeth to keep them from shifting.

 

[xy mosian]

Silly me. :idea: Of course morticing a great lump of timber before cutting the curves would be the way to do it, unless the curve is to be steam bent. There is no reason why, after bending, the rail could not be fixed to a support, lump of wood cut to fit, which would replace the straight edge reference. Imagine the piece that would have been cut from the piece if the rail were cut from the solid. That way a moriticng machine could be used. The suport could be any old timber.
xy

 

[SketchUp Guru]

I thought of mortising that way, too. If I were building this bed, I would not saw the rails out but rather steam bend them. If I were going to mortise the rails using a mortiser or router, I would certainly cut a support to hold the rail for the job.

 

[xy mosian]

Job sorted then?
xy