Home Built 13" Jointer #14: Table Lifting Screw - Nut Assembly

  • Advertise with us
Blog entry by Ger21 posted 04-18-2016 12:32 AM 2528 reads 1 time favorited 5 comments Add to Favorites Watch
« Part 13: Table Lifting Screw Part 14 of Home Built 13" Jointer series Part 15: It's running... »

This morning I set out to build the nut assembly that raises and lowers the infeed table.
I started with a piece of Delrin rod that I thought was 1.5” diameter.
Holding it with a handscrew, I marked the center and drilled a 3/8” hole through it.

I then took a cutoff piece from the screw to make a tap. I chucked it in my drill and while spinning, ground a taper on the disc sander. Then used an angle grinder to cut a rather sloppy flute in it.

Then chucked the tap in the drill press, and tapped the delrin by turning the chuck by hand.
This was very difficult for 3 reasons.
1) Poor quality tap. :-)
2) Removing a lot of material with 1 flute.
3) Delrin is slippery, and it’s hard to hold a round piece of it.

I could only do abnout 1/2 turn at a time, and had to back it all the way out to clear the chips.

Once tapped, checked the fit on the screw. Nice and snug. The reason I made it 1-1/2” long, was so that it would be on the tight side. The first 1/2”-3/4” of threads a bit loose, from running the tap in and out so many times.

I had some ideas in my head on how I was going to mount this, but thought of a better way this morning.

Whipped up some toolpaths in AutoCAD and carved out a slot to accept the nut. Except it wouldn’t fit. After a slight toolpath update and second run, I realized that the diameter was actually 1-3/4”, not 1-1/2”
Third time on the CNC was the charm, and I had a nice fit. Prior to routing the groove, I drilled 2 holes to locate T-nuts on the backside.

Then I clamped the nut to a block of wood on my CNC, and routed two flats, and drilled for the mounting holes that would line up with the t-nuts. I drilled a 1/8” hole, then countersunk with a countersink bit in a hand drill, followed by enlarging the holes by hand to 3/16” If I had a 3/16” collet for my cnc, I would have drilled them the right size to start with.

Screwed the nut to the base, and test fit on the screw.

Should work great. It’s nice and solid.

A few coats of paint tonight, and it’ll be ready to install tomorrow.

-- Gerry,

5 comments so far

View SPalm's profile


5338 posts in 5332 days

#1 posted 04-18-2016 12:49 AM

Clever work sir.
That is some good stuff.


-- -- I'm no rocket surgeon

View Don Broussard's profile

Don Broussard

4108 posts in 3701 days

#2 posted 04-18-2016 01:01 AM

Gerry—I’m enjoying the jointer build, vicarious as it is. You are doing some really great work with this project, and I am on the edge of my seat waiting for the shavings to start flying!

-- People say I hammer like lightning. It's not that I'm fast -- it's that I never hit the same place twice!

View MadMark's profile


979 posts in 2902 days

#3 posted 04-18-2016 01:30 AM

Don’t you need two? One for each side?


-- Madmark - [email protected]

View Ger21's profile


1100 posts in 4581 days

#4 posted 04-18-2016 01:33 AM

No. The outfeed table is fixed, and shouldn’t need to be moved once it’s set to the correct height.

-- Gerry,

View kaerlighedsbamsen's profile


1392 posts in 3163 days

#5 posted 04-18-2016 08:07 AM

Wow this build sure is getting along! Super fine finish on things. Hope this machine will serve you well and make you proud

-- "Do or Do not. There is no try." - Yoda

Have your say...

You must be signed in to post the comments.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics