A Simple Machine for making large (2 1/2″) diameter wooden screws

Alright!  I should have been cleaning up this hell hole that I call a shop.  I should’a just bought the damned things.  But wait a minute…

walnut "machine screw"

After forty hours or so of scratching my head and puttering around in the shop, I’ve managed to build two simple machines that will allow me to manufacture all of the big wood screws I want, in short order.  So if I figure my time at $35/hour, I’ll be in the black after I’ve made a dozen or so.  So, guess what everyone’s getting for Christmas this year.

Well okay.  If you only need a couple of big wooden screws, buy ’em.  However, it seems that a number of wooden screw manufacturers have come and gone in recent times.  So, it might be a valuable skill to have in your “toolkit”.

Here’s what did:

First, I laid out my spiral on the cylinder that would ultimately become the “lead screw”.  Then I sawed down to the root depth.

Note the "depth stop" held in place with a couple of small clamps

Then I built a “box beam” and eight (or so) “stantions” that will be used during the screw making process. 

some stantions are held fast, others are loose so they can moved during the process

Followers of this blog will immediately note that there is a router involved.  I’m sorry!!  But the machine is built in such a way that a manual cutter could be used.  But, you know, I’m getting older, I don’t know how much time I have left, I’m not as strong as I used to be….  So live with it!!  I used a router!!

router simply secured to the stantions by a couple of drywall screws

Then I used one of the stantions to mount two “lunettes”.  The lunettes are actually made from a .025″ x 12″ feeler gauge.  See Roy Underhill’s book, “The Woodwrights Workbook” for an excellent explanation of how this will work and remember that the lunettes must be offset by half of the pitch (you’ll figure it out immediately).  The “ramps” are set at an average angle of the pitch taken from the minor and major diameters.

Well, I’ll finish this up tomorrow.  It’s been a full day and, alas, it’s time to retire.

Explore posts in the same categories: Roubo workbench, wooden screws

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5 Comments on “A Simple Machine for making large (2 1/2″) diameter wooden screws”

  1. What is the router bit that you used and is cutting both sides of the V at the same time or one at a time?


    • D.B. Laney Says:

      It’s a Whiteside 60 degree V. I have found that it’s best to slow the feed rate and take the entire cut in one pass.

  2. m fink Says:

    “So, guess what everyone’s getting for Christmas this year.” I chuckled pretty good at that one. Cool project!

  3. Ray H. Says:

    “Woodturning Techniques”, by Mike Darlow.. Amazon Wont ship non digital to Oz. BAH!
    Pls explain how U laid out the spiral accurately, if U got time 🙂

    • D.B. Laney Says:

      Sorry for the delay in getting back to you. It’s a matter of “rise and run”. If you want make the vise close 1″ with each turn, you can get by with simply one longitude line and a strip of stiff paper. Mark out a series of ticks one inch apart on the longitude line, then connect from the first to the next with the paper, and so on. It’s amazingly accurate. You can increase the accuracy with more longitude and latitude lines. Remember to go the right direction, lest you have to manufacture a left hand nut.

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