The Hydraulic Fixture Table Project

Posted January 11, 2015

I began building metal art in 2010. I found it a challenge to work at different heights. Ergonomically, it was stressful on my back and it was often difficult to keep my hands steady. I had this Harbor Freight hydraulic table that I was using for lawn mower work and decided to retrofit it. A few years earlier, I attended a Fabtech conference in Chicago and saw commercially made fixture tables and although their heights were fixed, they were cosmically cool.

Rough specifications were to be able to:
1. work on the lower part of a sculpture at shoulder height
2. work on the upper part of a sculpture at shoulder height
3. sit while working
4. rest my wrists on a surface while welding
5. securely clamp work
6. make precise measurements off a flat surface
7. roll the project between work stations

Steps in the process:
1. secure a steel plate 3' x 3'
2. score lines in a 3" x 3" grid
3. drill holes in the center of each square and at each intersection
4. construct grillage to support the top
5. cut a wood plate and a thin steel plate, both 3' x 3'
6. attach the sandwiched top
7. adapt clamps to work with the top

Material:
1/4" thick steel plate
3/4" plywood
18 gauge steel sheet
5/8" nuts, blots, rod

Capacity:
Low height: 18"
High height: 40"
The table will hold 1,000 pounds.
The 1/4" plate weight 92 pounds
The 18 gauge steel sheet weighed 18 pounds
Miscellaneous attachments weighed ~30 pounds
Total dead weight ~140 pounds
Payload ~860 pounds

Notes:
The holes were hard to drill. Because of their location, they could not be done under a drill press. After scoring, I center-punched each hole location and then used a 1/2" drill with ever-increasing sized bits. It took a long time. Further, I renamed the DeWalt drill "911" because when the bit breaks through the far end of the steel, it wants to grab and abruptly stop.  The torque immediately transfers to your wrists and your ribs if you have stabilized the drill with your torso. I am not sure I would recommend this process. It would be far superior to have a friend with a CNC plasma table. 

The top is 4" off the base of the table. This is so the underneath can be reached with bolts to secure clamps. I built the table "sandwich" so that it had some mass to hold the clamps. The bottom sheet of steel acts like a big washer when 5/8" nuts secure clamps from beneath. 

This table rocks; seriously. I have used it for many projects. As you can imagine, vertical supports can be made to hold things horizontally over the table and spin in open space, if you are clever.

The following photos show the table, some useful tools, and a project that is underway. The project is a Ferris wheel sculpture that I have fabricated. I made the wheels on the table with bending equipment. They were secured with clamps for welding the spokes. The Ferris wheel is part of a carnival series and I have already finished the carousal. 

View from hydraulic end: foot pump & release handle

This shows the foot pump, release handle, grillage, and top. The table is at the top height of 40". the step ladder is about 24" high.


Here the table is at its low height of 18".

  This shows the underneath of the table.


From the back.


The top with showing the 5/8" holes.


Corner detail.


Scoring.


Typical clamps.


Clamps holding object in place.


Typical tools.


Fixture for holding round stock.


The Ferris wheel project head on. I make the "people" in the forge and they spin as the wheel turns :-)


The Ferris wheel project side view. The project now weighs about 80 pounds and I had to buy a hoist to move it on and off the table....the challenges never end but my Lord, it's fun.
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