How to Build a Torsion Box Workbench Top

Determine the correct proportions., Understand that it will need to be strong, heavy and durable., Make a level surface., Now lay your first sheet of mid grade plywood or MDF on top of the 2x4's., Start laying the inside grid of squares., Build your...

48 Steps 8 min read Advanced

Step-by-Step Guide

  1. Step 1: Determine the correct proportions.

    To build a workbench that is best for you, it must be the right height, width, and length, strong, durable and have features that make it user friendly.

    These features are things like a good vise or two, being a face vise or an end vise.

    Other elements that make it user friendly are things that relate to your style of woodworking: boat building or just piddling in the shop.

    Tool tray, bench dogs, bench slave and cabinets or shelves under the bench.

    One note here: a woodworking workbench is to work wood, so build it to meet that need.

    If you add shelves or cabinets below the top; be sure you can still use your bench dogs and hold fasts.

    You should also be able to use a clamp under the top.

    Tool trays are handy, but get in the way when you need to add a clamp on both sides of the bench to hold your work.

    Think about how you will use this bench and what you need to make it work with you.

    Think about your seven "P's": "Prior proper planning prevents pee poor performance".

    One word of caution here: don't build a workbench that is too large for your shop.

    Be sure you have room to work around the bench.

    If it is not what works for you, than it's not going to make you happy or productive.
  2. Step 2: Understand that it will need to be strong

    All torsion boxes have one thing in common: they have small grids or boxes inside one large box.

    This grid is what gives the torsion box it's strength.

    It is also one that will hold its shape and not twist or bend under normal workbench use.

    But you have to build it to fit the type of work you do and for its intended use.

    This will determine the size and shape of your torsion box top. , Making a level surface to start building is the first step.

    Level a set of boxes or saw horses or an area large enough for your project.

    Set rails or long 2x4's on top of them and level those. , This will be the bottom of your workbench top, checking again to ensure that all is still level.

    This will make for a nice flat top when the torsion box is finished.

    The 3/4" plywood or MDF should be slightly over-size to the top you want.

    This lets you lay out lines for your grid pattern and have room to trim it's flush with the main inside box.

    Lay out lines around the bottom plywood or MDF for the top size less the thickness of the outside hardwood trim boards that will rap around the top when done. , With the outside lines laid down, you can start laying out the inside grid or squares on the side of the outline.

    These squares should be of equal size along the length and width of the top.

    Here we will be using 1x2 lumber for the inside squares, so allow for the 3/4" thickness of each piece, all the short 1x2's across the width of the top should be the same length as should the long strips.

    This will ensure a strong and square grid pattern.

    Note:
    All the 1x2 lumber should be planed or run through the table saw to ensure they are all the same height. , Lay out the outside edge lines of the bench top on the MDF or plywood.

    Fit the frame together on these lines you laid out.

    Use screws or brad nails only long enough to pass through the width of the 1x2 and about 3/4 of the way into the plywood or MDF.

    Check the outside frame to ensure its square, measure from corner to corner in a diagonal manner.

    This outside frame will be glued and screwed or brad nailed to the bottom plywood or MDF.

    From here all is dependent on the squareness of the outside frame. ,, A carpenters square should be used on each short and long strip to ensure its square.

    Remove any excess glue, neatness is important to good craftsman like work. , Place the long strip into place making sure it touches all the short strips and touching the outside frame at each end.

    Brad nail at the intersections of the short strips and the long strips.

    You now have one row of your grid done, check to ensure that all remaining rows will be of the same width across the bottom. , Here you will have to toenail them to the long strip. , Use glue at the intersections where the short strips meet the long strips, this makes everything strong.

    Your last row of short strips should fit not too tight but touching the last long strip and outside frame as the first row of short strips.

    Check to ensure everything is square and the last row does not bow the outside frame member out. , After the grid has set overnight, attach it to the bottom plywood.

    This is the bottom of your workbench. , Check to ensure all is still level and square.

    Lay out lines on the bottom to match the centers lines of the 1x2's on the underside.

    On these lines you can add brad nails from the outside.

    This makes for a very strong box. , Place the top layer of plywood or MDF onto the grid.

    If you intend to use the torsion box for a very long time and intend to replace the top piece of plywood or MDF when its worn, than don't glue it in place.

    This can be done by laying out the center lines again for the grid below the top piece.

    Using pre-drilled holes, screw the top to the grid below, you can use nice brass or bronze screws and let them show for a nice contrast.

    Steel screws can be used if counter sunk and the holes plugged.

    Use enough screws into the grid and along the outside edges to make it very secure.

    No moment or giving of the top here.

    With this method you can replace the top plywood or MDF and have a new bench top again for very little money. ,, The corners should be mitered or use a nice box joint here.

    Glue and screw the outside trim into place, do not glue it to the top plywood or MDF.

    The hardwood outside frame top and bottom outside edges should be rounded over to prevent splintering.

    Your torsion box is now done and should be about 3" thick by what ever length and width you have chosen. , Oil finishes as 1/2 boiled linseed oil and 1/2 tongue oil,about 3 coats. , This new torsion box top is not just strong, stiff and durable but heavy and should have a heavy frame to hold it. , At your local lumberyard, pick out the best 2x6's and 2x8's you can find.

    The grade and quality of these depend on your budget.

    Yellow pine is really good for this and still much less than any hardwood. ,, It should be high enough that you don't have to bend over to work and not so high that you have to reach up. ,, You can use scrap pieces for this to ensure proper location of the short leg lamination. , These pieces are for the foot, they should have a small amount of material removed from the center bottom section of each foot to let it set level. , Use a framing square to make sure that the legs and foot fit square.

    This should give you a nice inletted look for the foot.

    All lag screws should be long enough to pass through the foot/rails and about 2-1/2" into the legs, just don't let go completely through. , As with the foot piece it should also be glued and lag screwed into place.

    This to should give you an inletted look. , These should be the length of your bench less the amount of overhang used for mounting vises.

    The long side rails should overlap the end rails at the corners of the legs. , Two trimmed 2x4's attached to the top edge of the foot will also make a good base to build shelves or storage cabinets under your new workbench. ,, Placing four pieces, one at each end of the base frame and two more evenly spaced from the ends and pre-drilled for screws to attach the top torsion box.

    This inexpensive workbench can have lots of extras as, tool tray added to one side of the torsion box.

    It can also have vises attached to the overhang end as in a face vise and an end vise.

    You can add bench dog holes, these should be decided on before building the top torsion box.

    To have bench dogs in a torsion box, you need to install a trimmed 2x6 one row from the outside edge.

    This trimmed 2x6 is glued and screwed to the bottom inside and out.

    Placing screws at locations that will not interfere with the drilling of dog holes.

    More features as built in cabinets or shelves under the center section of the base frame.
  3. Step 3: heavy and durable.

  4. Step 4: Make a level surface.

  5. Step 5: Now lay your first sheet of mid grade plywood or MDF on top of the 2x4's.

  6. Step 6: Start laying the inside grid of squares.

  7. Step 7: Build your outside box frame

  8. Step 8: use the 1x2 lumber

  9. Step 9: pre-drill holes or use a brad nailer and glue.

  10. Step 10: Cut your 1x2 lumber to the proper lengths for the grid

  11. Step 11: use long pieces the length of the bench and short 1x2's across the width.

  12. Step 12: Place the short strips at their pre-determined location of the grid against the outside frame along the length of the bench.

  13. Step 13: With the short strips in place for the first row

  14. Step 14: you can now add a long strip in the same manner

  15. Step 15: glue and screws in pre-drilled holes or brad nails.

  16. Step 16: You can now place more short strips into place as you did the first row of short strips

  17. Step 17: glue and screw or brad nail them in place making sure they are square to the long strip.

  18. Step 18: Now you can place another long strip in the same manner as the last long strip and then add the short strips as the previous row with glue screws and or brad nails.

  19. Step 19: Let the glue dry overnight before doing anything else.

  20. Step 20: When the glue has dried overnight

  21. Step 21: get help and turn the bottom and grid over placing it back on the 2x4s you used to make a nice flat level surface.

  22. Step 22: When the brad nailing on the bottom is complete

  23. Step 23: you can again turn over the bottom

  24. Step 24: again check for flatness and square.

  25. Step 25: Once the new torsion box is together

  26. Step 26: you can trim the outside edges of the top and bottom plywood or MDF flush with the outside edges of the outside 1x2 frame.

  27. Step 27: The outside trim is a hardwood of 1" to 1-1/2' thick and the width of the thickness of the torsion box.

  28. Step 28: After rounding over edges and sanding the entire top

  29. Step 29: you can put a nice oil finish on the torsion box to keep it looking good and prevent any other problems from water or whatever may come in contact with it.

  30. Step 30: You should build a nice strong 2x frame with 3 layers of 2x6 material for legs.

  31. Step 31: The frame for your top can be very inexpensive and still look like a million dollars.

  32. Step 32: Trim the outside edge of the 2x6 and 2x8's

  33. Step 33: cut the rounded edge off

  34. Step 34: about 1/4"-5/16" will square the edges.

  35. Step 35: Cut the 2x6's to length for the legs

  36. Step 36: this is up to you as to how high you want your bench top.

  37. Step 37: Cut one of the 3 2x6 lamination shorter by the width of the bottom trimmed 2x6 foot and the top trimmed 2x8 rail.

  38. Step 38: With the 2x6's cut to length and trimmed to width

  39. Step 39: glue and screw them together making sure you leave the right amount of space for the foot at the bottom and right amount at the top for the top rail.

  40. Step 40: Cut 2 trimmed 2x6's the length of the width of the base frame plus about 3" over on each side of the legs.

  41. Step 41: Glue and lag screw the foot (trimmed 2x6) to the legs at the pre-determined end for the 2x6 foot.

  42. Step 42: The next piece to add is the top rail

  43. Step 43: this should be just the length of the width of the bottom of your base frame.

  44. Step 44: Now that the leg assembly is complete

  45. Step 45: you can attach the long trimmed 2x8 side rails with glue and lag screws.

  46. Step 46: A stretcher between the foot pieces can be added if wanted.

  47. Step 47: The base frame can also have a nice oil finish after rounding any edges that are subject to splintering and sanding it all smooth.

  48. Step 48: The top torsion box can be placed on top of the base frame and attached with figure eights or you can install cross pieces about 2x3" at the top rails of the base frame.

Detailed Guide

To build a workbench that is best for you, it must be the right height, width, and length, strong, durable and have features that make it user friendly.

These features are things like a good vise or two, being a face vise or an end vise.

Other elements that make it user friendly are things that relate to your style of woodworking: boat building or just piddling in the shop.

Tool tray, bench dogs, bench slave and cabinets or shelves under the bench.

One note here: a woodworking workbench is to work wood, so build it to meet that need.

If you add shelves or cabinets below the top; be sure you can still use your bench dogs and hold fasts.

You should also be able to use a clamp under the top.

Tool trays are handy, but get in the way when you need to add a clamp on both sides of the bench to hold your work.

Think about how you will use this bench and what you need to make it work with you.

Think about your seven "P's": "Prior proper planning prevents pee poor performance".

One word of caution here: don't build a workbench that is too large for your shop.

Be sure you have room to work around the bench.

If it is not what works for you, than it's not going to make you happy or productive.

All torsion boxes have one thing in common: they have small grids or boxes inside one large box.

This grid is what gives the torsion box it's strength.

It is also one that will hold its shape and not twist or bend under normal workbench use.

But you have to build it to fit the type of work you do and for its intended use.

This will determine the size and shape of your torsion box top. , Making a level surface to start building is the first step.

Level a set of boxes or saw horses or an area large enough for your project.

Set rails or long 2x4's on top of them and level those. , This will be the bottom of your workbench top, checking again to ensure that all is still level.

This will make for a nice flat top when the torsion box is finished.

The 3/4" plywood or MDF should be slightly over-size to the top you want.

This lets you lay out lines for your grid pattern and have room to trim it's flush with the main inside box.

Lay out lines around the bottom plywood or MDF for the top size less the thickness of the outside hardwood trim boards that will rap around the top when done. , With the outside lines laid down, you can start laying out the inside grid or squares on the side of the outline.

These squares should be of equal size along the length and width of the top.

Here we will be using 1x2 lumber for the inside squares, so allow for the 3/4" thickness of each piece, all the short 1x2's across the width of the top should be the same length as should the long strips.

This will ensure a strong and square grid pattern.

Note:
All the 1x2 lumber should be planed or run through the table saw to ensure they are all the same height. , Lay out the outside edge lines of the bench top on the MDF or plywood.

Fit the frame together on these lines you laid out.

Use screws or brad nails only long enough to pass through the width of the 1x2 and about 3/4 of the way into the plywood or MDF.

Check the outside frame to ensure its square, measure from corner to corner in a diagonal manner.

This outside frame will be glued and screwed or brad nailed to the bottom plywood or MDF.

From here all is dependent on the squareness of the outside frame. ,, A carpenters square should be used on each short and long strip to ensure its square.

Remove any excess glue, neatness is important to good craftsman like work. , Place the long strip into place making sure it touches all the short strips and touching the outside frame at each end.

Brad nail at the intersections of the short strips and the long strips.

You now have one row of your grid done, check to ensure that all remaining rows will be of the same width across the bottom. , Here you will have to toenail them to the long strip. , Use glue at the intersections where the short strips meet the long strips, this makes everything strong.

Your last row of short strips should fit not too tight but touching the last long strip and outside frame as the first row of short strips.

Check to ensure everything is square and the last row does not bow the outside frame member out. , After the grid has set overnight, attach it to the bottom plywood.

This is the bottom of your workbench. , Check to ensure all is still level and square.

Lay out lines on the bottom to match the centers lines of the 1x2's on the underside.

On these lines you can add brad nails from the outside.

This makes for a very strong box. , Place the top layer of plywood or MDF onto the grid.

If you intend to use the torsion box for a very long time and intend to replace the top piece of plywood or MDF when its worn, than don't glue it in place.

This can be done by laying out the center lines again for the grid below the top piece.

Using pre-drilled holes, screw the top to the grid below, you can use nice brass or bronze screws and let them show for a nice contrast.

Steel screws can be used if counter sunk and the holes plugged.

Use enough screws into the grid and along the outside edges to make it very secure.

No moment or giving of the top here.

With this method you can replace the top plywood or MDF and have a new bench top again for very little money. ,, The corners should be mitered or use a nice box joint here.

Glue and screw the outside trim into place, do not glue it to the top plywood or MDF.

The hardwood outside frame top and bottom outside edges should be rounded over to prevent splintering.

Your torsion box is now done and should be about 3" thick by what ever length and width you have chosen. , Oil finishes as 1/2 boiled linseed oil and 1/2 tongue oil,about 3 coats. , This new torsion box top is not just strong, stiff and durable but heavy and should have a heavy frame to hold it. , At your local lumberyard, pick out the best 2x6's and 2x8's you can find.

The grade and quality of these depend on your budget.

Yellow pine is really good for this and still much less than any hardwood. ,, It should be high enough that you don't have to bend over to work and not so high that you have to reach up. ,, You can use scrap pieces for this to ensure proper location of the short leg lamination. , These pieces are for the foot, they should have a small amount of material removed from the center bottom section of each foot to let it set level. , Use a framing square to make sure that the legs and foot fit square.

This should give you a nice inletted look for the foot.

All lag screws should be long enough to pass through the foot/rails and about 2-1/2" into the legs, just don't let go completely through. , As with the foot piece it should also be glued and lag screwed into place.

This to should give you an inletted look. , These should be the length of your bench less the amount of overhang used for mounting vises.

The long side rails should overlap the end rails at the corners of the legs. , Two trimmed 2x4's attached to the top edge of the foot will also make a good base to build shelves or storage cabinets under your new workbench. ,, Placing four pieces, one at each end of the base frame and two more evenly spaced from the ends and pre-drilled for screws to attach the top torsion box.

This inexpensive workbench can have lots of extras as, tool tray added to one side of the torsion box.

It can also have vises attached to the overhang end as in a face vise and an end vise.

You can add bench dog holes, these should be decided on before building the top torsion box.

To have bench dogs in a torsion box, you need to install a trimmed 2x6 one row from the outside edge.

This trimmed 2x6 is glued and screwed to the bottom inside and out.

Placing screws at locations that will not interfere with the drilling of dog holes.

More features as built in cabinets or shelves under the center section of the base frame.

About the Author

S

Samuel Henderson

Samuel Henderson specializes in educational content and has been creating helpful content for over 5 years. Samuel is committed to helping readers learn new skills and improve their lives.

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