Building a Pen Press

Building a Pen Press
By Chuck Arkon

Bill of Materials

1 - 18” X 4” X ¾” 6061 Aluminum Bar Base Plate
1 - 4” X 1 ¾” X 1” 6061 Aluminum Tail Piece
1 - 1” X 2 ¼” Amco Bronze Tail Piece Bushing
2 - 3/8” X 2” Cap Screws
3 - 3/8” Flat Washers
1 - ½” X ½” Brass Rod Cotter Nut
1 - ½” X ¾” Brass Rod Cotter
1 - M6 x 1 Adjustable Handle (McMaster-Carr), (http://www.mcmaster.com)
P/N 60235K31 $6.09 Ea.
1 - 6mm Flat Washer
1 - #609 Destaco type Horizontal Toggle Clamp (McMaster-Carr)
P/N 5093A43 $20.01
1 - ½” X 11” Cold Roll Steel Rod Tail Piece Follower Rod.
4 - ¼” -20 X ¾” Socket head cap screws Toggle Clamp Mounting Bolts.
2 - M5-.8 X 20 Socket head cap screws Handle Extension Attachment Screws.
1 - 5/8” X 16” Heavy wall steel tube Toggle Clamp Handle Extension.
1” Dia. UHMW Rod (McMaster-Carr) P/N 8701K45 $1.80 per ft.
1” Dia. ACETAL (DELRIN) Rod (McMaster-Carr) P/N 8576K21 $4.16 per ft.

Machining & Assembly:

Tail Piece Block: (Refer to Fig. 2,5,6 & 7)
Square tail piece block to 1 11/16” X 4”.
Bore tail piece block, 1” on C/L to the width same height as the horizontal height of the Toggle clamp.
Face off 1” Amco Bronze stock.
Turn down Tail Piece Bushing O.D. to match bore in Tail Piece Block along it’s length for 2”, a light press fit is ideal.
Step drill the bushing to ½” dia. 2 ¼” deep.
Part off bushing at 2 1/8” from end.
Press bushing into the Tail Piece Block.
Set up block in mill vise, square to the table.
Bore 13/32” holes through on C/L ½” in from each edge.
Bore ½” through hole on C/L 1 ½” in from edge of block for Cotter.
Mill steps into top of block ¼” deep by 1 1/16” (to lower bolt heads)

Mounting Toggle Clamp: (Refer to Figure 1)
Align toggle clamp on C/L of Base Plate and locate mounting screw holes.
Drill through and tap the mounting holes for ¼”- 20.
Mount Toggle Clamp on Base Plate.

To Make Tail Piece Cotter: (Refer to Figures 2 & 3)
Cut ½” brass stock 1 ½” long.
With ½” end mill, side cut 1/8” deep, 5/8” from one end.
Part off ½” from end (in middle of end mill side cut)
Drill through and tap the ½” long nut M6 - 1.
Drill through the ¾” long piece to ¼” for M6 clearance.

Assemble Tail Piece: (Refer to Figures 2 & 5)
Secure Tail Piece Follower Rod in the block, with rod extended far enough to contact Toggle Clamp Plunger.
Align the rod and the plunger, and transfer the mounting holes location.
Drill through and tap the holes for 3/8” - 16
Mount the Tail Piece assembly to the Base Plate with 2” 3/8” cap screws and washers.
Make Toggle Clamp Handle: (Refer to Figures 4 & 10)
Remove and discard the plastic handle from the Toggle Clamp.
Mill a slot in the Handle Extension to accommodate the Toggle Clamp handle.
Knurl approx 4” of opposite end of Extension Handle.
With the handle extension on Toggle Clamp drill through with M5-.8 tap drill.
Remove Handle and re-drill 1 side of the handle to clearance hole for M5.
Tap the remaining side of the handle for M5-.8.
Re-drill the Toggle Clamp handle to clearance hole for M5.
Mill shallow flat in handle at bolt holes for screw heads.
Replace handle on the Toggle Clamp and secure with the M5-.8 socket head cap screws.
Preparing Rod and Plunger for Push Pads: (Refer to Figures 1 & 2)
On Tail Piece Follower Rod, machine shoulder 7/16” dia. X ½” long on one end.
Insert M8 bolt cut off so that approximately ½” of plain shank is left sticking out with no threads. Place thread lock on the threads.
To Make Follower End Push Pads: (Refer to Figures 8 & 9)
At least 1 each of UHMW and ACETAL are required or 2 ACETAL Push Pads are required. They must be bored on one end for the mounting on the Tail Piece Follower Rod and the Toggle Clamp Plunger. It is important that both faces be square and smooth.
With a #4 center drill, drill down to the start of the angle cutter on the drill on one end of the UHMW piece or one of the ACETAL pieces. This is to center the pen tip during assembly.

When assembling a pen, I prefer the pen tip to be on my left and the toggle clamp to be on my right. You lefties might want to turn it around.
You can make as many Push Pads as you want to customize your press for different projects.
This press will last a couple of life times and if you scrounge the materials and do the work yourself as I did, the cost is very reasonable. (Refer to Figure 11) Good luck with yours.

Chuck Arkon