charpoi bench

[johnnyb]

thought I'd post up how I went about making this bench from beech. it was inspired from 1275gts build and my need for a bench! 1275gt is building a danish stool which is a lovely design. but I've also tried to build a charpoi in the past without success but still had an itch

 

[johnnyb]

the first job was to make a template( for the main crossmember) that I guessed would be sturdy enough for a couple of hefty adults and of course be pleasing to look at. I ended up making a 110 inch tramnel( I usually drill a 30mm hole and then pop a 30mm bush on the router then run that around. it didn't need to be perfectly positioned as I could adjust the sizes and even it up with the tracksaw

 

[johnnyb]

with the template made and adjusted to look OK. I thought about the thickness of wood that would be sturdy enough to cope without stretchers. I reckoned 30mm was the section needed. to try and end up with neat through mortices I used a hollow chisel morticer with an angle block. the angle I arrived at was to make sure the legs didn't stick past the end of the bench when at the correct height ( 18 inches) the angle was marked with a slide bevel and the width guessed at ( 2 1/2 inch).
next the crossmember radius was marked using the template it was important to mortice past that line so when the rad was template cut a nice clean mortice was revealed.

 

[johnnyb]

next was trimming the large radius on the spindle with a bearing guide. I don't have any pics but it basically bandsaw as close as possible to the line then trim.
next I made a ply pattern for the legs including the through tenon. I simply used the template again( after trying 3 different shapes) so the legs have a radius. the tenons were marked once again making sure the legs didn't stick beyond the end of the bench when at 18 inch height. these were then cut using a wedge on the morticer

 

[johnnyb]

the legs were then bandsawn and sanded to the line.the slight gaps arising from the crossmember radius and the tenon shoulder were addressed by marking lines where the legs sat on the crossmember and carefully planing these flat.
next came the four top rails. these required 3 degree tenons on each end and straight through mortices making the legs splay 3 degrees out to the side only about 1 1/2 knch overall. I really prefer to use the leigh mft for tenons this size especially with angles involved. After pondering sizes and positions I judged 10mm by 45mm tenons on 20mm by 55mm rails. I had to Jerry rig holding the crossmember using clamps but it was fairly simple really leaving neat through tenons using a compression bit. the tenons were machined by tilting the carriage at 3 degrees.

 

[johnnyb]

these were to be wedged tenons before assembly the bits that would be at the top edge of the crossmember were rounded for comfort. everything was sanded before assembly. the legs were drawbored as the angles made these awkward to clamp. the 2 assemblies were the joined used the angled rails and clamped and wedged. the legs had thin wedges inserted just to fill any gaps.

 

[johnnyb]

next this was finished with 3 coats of 10% ac lacquer. denibbing after the first coat. finally the weaving..
this was fairly straightforward using cotton webbing specially made for these daybeds in Pakistan. this was doubled then stapled on the frame before being wrapped and tightened then interwoven the other way making everything as tight as humanly possible.

 

[johnnyb]

reading back put tenoner instead of morticer. it's interesting how many design decisions are educated guesses in particular for strength assessments. I want this to last but not be overbuilt. these objects are for use primarily and decoration to but without that sturdiness they fall flat.