Finally some wood to work with.

[4DThinker]

A trip to visit my retirement adviser did double duty as on the way back I picked up some 6/4 Cherry and Baltic Birch Plywood.  My plan is to make 4 copies of a folding desk design I made when in college. 

This time the legs, stretchers and top trim will be cherry rather than the maple I used originally. 

Slow steps.  Patience to maximize the part yield I can get from the 3 cherry boards I bought. 

First part will be the desk sides.   2" tall. 24" long, 1.25" thick.  Here is a render from Aspire showing the outcome from CNC pockets and end profiles for the sides.  Left and right version will be needed. 

 

I have some joinery details to work out, and need to figure out the best way to clamp the rough rectangles to my CNC bed to make the cuts. 

Slow steps.   No rush.   I'll post updates for this project as I proceed. 

4D

[4DThinker]

With mortises to receive the from and back edge trim of the top.

4D

 

[Grandpadave52]

Interesting project 4D. I'll be following along.

[Cal]

Great project 4D, I'll also be following along and trying to keep up.

[lew]

Cool design. Are you making the Balans chair, too?

[4DThinker]

3 minutes ago, lew said:

Cool design. Are you making the Balans chair, too?

Nope.   The one shown in the photo was one of 30 or so, student designed, that were mass produced for fledgling computer labs at the university I taught at. We found that the rear single caster carried most of the weight of the occupier.  On the softwood fir floors of the ancient building I taught in they tended to dig pits into the wood.  An unanticipated design flaw.   I personally went on an iterative pursuit for a better design, and have posted most of the variations here:  My Blog    Ultimately the designs stretched the base to allow 4 caster rather than three.   

4D

[4DThinker]

Side View layout.  The front leg that runs from the front floor corner to the rear desktop corner I make from a single strip, cutting off one end to glue to the side for the hook area.  I'll make the one inch thick stretchers from 6/4 thick wood by ripping 1" wide strips from the board, laying them down, and gluing them together to make 1" thick blanks. Top stretcher is 3" wide and bottom stretcher is 4" wide.  

 

4D

[4DThinker]

Debating with myself about the body of the top of this desk.  The original had the top plywood piece glued in, and the bottom 1/4" hardboard piece screwed in place.   The frame parts were glued together with dowels.  No CNC to use back then (1980ish).  I like the thought of access to the inner core.  The center drawer only takes up 1/3 of the width, leaving 1/3 on each side. A potential hiding place for this or that. 

The back legs bolt into the top frame.  Originally I embedded a cross dowel for them to thread into.  For these I'll use my CNC to embed a square nut from the inside face. That bolt also holds the side piece of the top in place even if it isn't glued in. I could also bolt the front corner of the side to the front rail using no glue.  This would allow the side pieces to come off, giving access to the end core sections.  A little more sophisticated joinery could also lock the top plywood and the bottom hardboard in place when the sides were bolted in. Front and back rails would be glued to the top and bottom. Drawer rails would also be glued in place. 

 

So if you had a hiding place in a piece of furniture, what would you hide there?   Access wouldn't be easy or obvious. I have thought of CNCing a QR code on the inside face of the side pieces.  If you took them off and scanned the code it would link you to my blog post about this desk.  If I'd written a book I'd hide one in the desk. Maybe a brick of cash?   A treasure map with every location where a copy of the desk lives?  Owners asked to mark their current address on the map  and re-hide it in the desk. 

4D 

[Grandpadave52]

2 hours ago, 4DThinker said:

So if you had a hiding place in a piece of furniture, what would you hide there? 

Well since you ask, likely a 9mm "hole shooter" and a couple extra "bit" magazines.

[4DThinker]

26 minutes ago, Grandpadave52 said:

Well since you ask, likely a 9mm "hole shooter" and a couple extra "bit" magazines.

Thought about that.  Figure if I had a 9mm and needed to use it, then hiding it in a desk that had to be taken apart to get it would defeat the intended purpose.  

I did have a student once that designed a standing cabinet with a recess in the back where he could hide and yet quickly access his weapon.  A rare occurrence though as over 4 decades he was the singular instance out of 400ish students seen over all those years. 

 

Had a tricky thought about hiding the specific Allen wrench needed to undo the bolts that lead to it.  Next idea was a hidden compartment inside one hidden compartment.  A long screwdriver would be needed to reach and loosen the screws holding it in. The long screwdriver could be hidden in the other hidden compartment.  Maybe inset into the side panel itself, covered by a discrete sliding lid and not obvious to notice.      

[KevTN]

I like that design

[4DThinker]

Thanks KevTN.  Designed it in college back in the 80's.  It won 1st place in the case goods category at IWFs Design Emphasis Furniture Design Competition.  A furniture company down in Tennessee picked it up to produce, but failed to sell any to their regular retail kitchen stores. They made microwave carts and other wood kitchen accessories and sold to Kitchen Plus type stores.   Wrong market apparently for a portable desk. 

More photos: https://4dfurniture.blogspot.com/2022/08/a-folding-desk-my-award-winning-design.html

4D

  

[KevTN]

Does that computer run your CAD?

[4DThinker]

1 minute ago, KevTN said:

Does that computer run your CAD?

Nope.   That is an original TI99/4A.  The first PC I owned and it came out before any IBM PC compatibles did.  Used program cartridges or cassette tape.  Had built-in BASIC I could write programs with.  Used a tube TV for video.  Thought it would add some context/scale to the photo. 

4D

[Fred W. Hargis Jr]

I like that desk, but i wonder how many folks recognize that style of chair. In the mid 80s I bought 2 of them  (one on casters, the other was a rocker type) for my office. They never did catch on, but the chairs do work very well in keeping your back straight.

[4DThinker]

Balans chairs.  The rocker version was the original.  The ones with casters were a knock off that failed to consider the dynamic nature of the rocking version which kept occupants from getting stiff while sitting.  All failed because there are ancient regs out there that state for office/commercial use all chairs must have a back.   We had one of the original Balans rockers used by the department secretary for awhile. Recovered the seat and knee pads at least once.  I made a series for research which helped me get promoted back then:  https://4dfurniture.blogspot.com/2022/09/iterative-progression.html

Ultimately I concluded that rocking was the right track and designed/made this one:  https://4dfurniture.blogspot.com/2022/07/rocking-balans-chair.html

4D

  

Edited January 27, 2024 by 4DThinker

[4DThinker]

Sorry about not posting progress with the desk design.  Latest thoughts are to modify the side boards with slots to trap the bottom and top boards of the desk top.  Figured if the side were bolted in place then all the parts should be trapped when the sides are attached.  Simplify assembly by eliminating any need to glue up the desk top parts.  Challenging part is the front side of the desk,  It is broken into three parts so the center section can be a drawer front.  The back board of the desk top is one continuous piece. Both ends bolt to the sides.  Bolting to the two side sections of the front I need to figure out how to trap their inner end.  I'll see if I can post a drawing that shows the challenge.

4D

Edited February 8, 2024 by 4DThinker

[4DThinker]

Center open area is where a drawer will slide in. There will be sides for drawer slides between the back and front frame.  Those pieces would be trapped if the front side was continuous, but obviously the front side ends are only attached at one end. I thought about pinning through the top 1/2" ply and bottom 1/4" ply and trap the inner ends, but that isn't a knock-down solution.  A spring loaded connection of some sort might do but I haven't envisioned how it would be implemented yet. Pull the drawer out to reveal a push button or lever that releases the inner drawer frame?  Something like that.  Such is how my mind works. 

4D

[4DThinker]

One option, and likely the final option, is to dovetail the drawer slide support rail into the back piece, and notch into it with the front frame piece.  Mount the drawer slides to this piece, and when the drawer is inserted it will keep the parts hooked together at the front.  

4D

[4DThinker]

For that rear dovetail connection I can use my CNC to make it slightly taper down from the top for easy insertion and removal. Once in place with the bottom and top panels in place it can't come out. The top and bottom panels will have rabbeted edges that tuck into the perimeter frame and will be trapped in place once the ends are screwed on to the front and back frame parts. So that they are easy to slide in but are snug when inserted I can also put a slight taper on the slots and the rabbeted perimeter.  Just a couple of degrees. 

 

The front joint also needs to be a reliable knock-down version that won't wear down coming apart repeatedly.   Not that I imagine this desk body being take apart frequently, but just to be sure if it is it'll always go together as "perfectly" as it does the first time I assemble it.  Still thinking about how to make it a snug fit but easily come out and go back in snug.