Introduction: Extreme Heavy Duty Work Bench
I have an area in the old barn that is unused and I wanted to convert to a 'rough' working place. The floor is unlevelled , which require adjustable feet to adjust for the height difference up to 30 mm. The angle of the wall corners are not perpendicular, they are more like 86 to 93 degrees, which require a remissive design.
This is an extreme heavy duty work bench that can be used for really large weights. A bench that I built some years ago according to the same concept, was acting as a stand for a metal bench mill and lathe of approx. 200 kg totally, without any problems.
My build is 4.8 m long and 2.0 m wide at the sides. The work area is 800 mm deep (from front to rear) and 850 mm high from the ground.
The first thing you must ask yourself is:
- Should there be any heavy, permanently mounted machines at the bench? And where should they be?
- Will you have any vice (or several vices) mounted at the bench? And where should they be located?
The reason for you to ask these questions now, is that you should locate the cross sections directly below the loads to give the bench a firm support.
Some general tips according vices:
If you work with long objects, consider mounting two vices in line with each other. Obviously more expensive but definitely worth it!. Or if you build a shorter bench with a 90 deg. sideboard you can also use two vices, if they are rotatable
Calculate the number of cross sections needed. I recommend distance of approx. 1.0 m between each section. The bench may be unstable and not sturdy enough if a distance larger than 1.2 m is used.
As a general rule I never place any wood material in direct contact to concrete because moisture can/will be transported through the concrete and into the wood. So a gap, or a large washer, between wood and concrete is advisable.
Also consider any electrical wiring to power outlets, if needed. It's a good idea to have figured this out before building the bench.
What you need:
- Ordinary wood working tools.
- General wood screws, countersunk (I.e. diam: 5 and length 55).
- Angle brackets, 50x50x35x3.0 - 4 per cross section.
- Angle brackets ,90x35x35x3.0 - 1 per cross section.
- Large screws, nuts and washers for adjustable feet: Hex bolt head M20x80 or longer. 2 per cross section
- A lot of wood for building.
- Laminate floor as protection surface
- Vices: Optional
Total cost for 4.8 m x 2.0 m (in Swedish Krona, SEK):
- Bench plate wood: 1060 SEK
- Wood for cross section, lower shelf and additional pieces: 520 SEK
- Laminate floor: 336 SEK
- Angle Brackets 50x50: 72 SEK
- Angle Brackets 50x90: 48 SEK
- Hex bolts, nuts M20 and washers: 250 SEK
- Wood screws, fasteners, etc.: 200 SEK
Total cost in USD: 2486 SEK => 380 USD (Feb 2014: USDSEK = 6.55)
Step 1: Lining Up
First of course, fix the walls if they are damaged.
Start by drawing a horizontal levelled line at the walls describing the final working upper surface. (I am quite tall and prefer a working surface height of 850 mm). Be VERY careful that the line is absolutely horizontal because the whole build will rely on this line. Use a long level or a line laser. Double check the line position.
Find out where the cross sections will be located and at what height. The height is calculated by subtracting the total bench plate thickness together with the upper cross section height, from 850. In my case: 170 mm below upper surface.
Firmly fasten the larger consoles 90x35x35x3.0 at the walls (with plugs if it's concrete). The purpose of these are to give you a small gap between the wood and the concrete wall, and secure the bench to the walls. It's very frustrating if the whole bench moves around or rattles when you are working furiously with some mean parts that need persuasion...
Step 2: Cross Sections
Start building the cross sections with wood in dimension 45x95 mm.
Make it approx. 30 mm longer than the depth of the table surface. You will cut this to correct length later on...
Front and rear vertical part / legs:
Cut to wanted heights and connect with angle brackets.
Lower connection / lower shelf support:
Mount one thinner wood on each side. Observe to screw them diagonal opposite on each side. There should be space for the feet screw between the fastening screws.
Make the length same as the wanted total width of the lower shelf.
Drilling feet hole:
When assembled turn it upside down and drill a 20 mm hole in the bottom of each leg.
- Mount the assembled feet (screw, nut and washer).
- Mount the completed cross section units to the wall angle brackets.
- Use some leftover spare plank to temporarily connect them together to prevent them from falling.
Step 3: Lower Shelf
Start building the lower shelf by screwing shelf supports at the cross sections.
Use planks that 'goes into' each other with a tongue and groove for firm support.
Step 4: Fastening Middle Part
To be able to mount the table 'framework' to the cross sections, a middle piece is needed.
Suitable dimensions: 21x120 mm. Make it approx. 30 mm longer than the wanted table surface. You will cut it to correct length later.
Screw the middle part, from above to the upper part of the cross section. Use several screws, at least 5. Repeat at each cross section.
Note: This part will be exposed to large forces later on when the table framework beams are mounted. That's because the beams are usually a little bent and twisted and needs to be screwed really tight to be straight.
Step 5: Main Table Framework
The table framework should be assembled of wood beams. All of them with a thickness of 45 mm.
You have to calculate which sizes that should be used. My bench plate surface is 800 mm deep. That gives me the following standard wood beam widths:
That equals 780 mm.
And with 5 mm gaps between the planks gives: 4x5 = 20
Total bench deep: 800
Also: Se drawing at step 'Cross Sections'
Cut them in correct lengths and loosely put them on top of the cross sections middle part. Place them with a 5 mm gap between each other and to the wall. That's because they often are little bit bent or twisted.
Screw the innermost beams to the middle piece from below. Don't fasten the outer beam yet.
Put a mark with a pen at the cross section middle part, where the outer beam ends. Cut the cross sections 10-20 mm in from the pen mark, making it a little bit shorter than the finished table. Cutting a chamfer will look nice.
When the cross section upper part is cut: Fixate the outer beam from below.
Step 6: Protection Surface
To protect the bench you must have an upper protection surface.
Use oil hardened board, 5 mm thick. That will do fine. My other work benches have this and its good enough and will last for years. Make sure that it is of high quality, some boards are quite soft even when oil hardened.
Use fake wood laminate floor. Gives a semi hard surface, easy to clean, easy to work with and possible to replace single tiles. Sometimes even cheaper than oil hardened board. Laminate floor exist in several classes of hardness, use a hard one. A very exclusive look is a bonus ;)
In either way:
Screw the protective surface to the wooden beam framework with small countersunk screws. Allow the protections surface some 3-5 mm oversize.
If using laminate floor, start in a corner and work yourself outwards from there. Remember that the laminate 'moves' a bit when cold/warm and more/less moisture in the air. It must be possible to 'float' in one direction, therefor leave a gap of 5 mm to the wall.
When firmly secured with screws: Remove the oversize with a rasp and a flat oscillating sander.
Step 7: Vices (additional)
Here are some tips to consider when buying and mounting a vice:
- Most important: Do NEVER, ever, buy a vice that doesn't allow the inner fixed jaw to be positioned outside of the workbench edge... just forget it.
You will, guaranteed, after a while be lunatic insane at a vice with this design 'flaw' and throw it out the window (without opening it). Large or tall objects MUST be possible to fasten when they have to pass below the workbench surface. Surprisingly and very strangely, a lot of crappy designed vices do not allow this. Even the expensive ones.
- Always mount the vice above a cross section.
- Use two vices mounted in-line if you handles long objects. If they are rotatable you don't have to place them in-line, one at a sideboard of the bench will do fine.
Think twice before drilling the vice's fastening holes in your new workbench. Ask yourself: Is it possible to handle long object with the vice in this position? Will the vice be in the way almost all the time, because I usually want to work exactly at the same place due to good light / or near some useful tool, or whatever?
- Before mounting the vice to the workbench, disassemble the vice and put a lot of grease to all moving parts.
- Always use protection jaws. I mostly use 3 kinds: aluminum (with V-grooves for small round objects), flat rubber surface and hard plastic. I also have some larger wood pieces for fastening of wood objects.
- When not in use, do not tighten the jaws, always keep them a bit apart.
Step 8: Drawers (additional)
Buy some 12 mm construction plywood for the bottom and some 12x90 mm planks for the sides. Make a frame with suitable dimensions that fist between the cross sections.
Tip: If the work bench is 800 mm deep, make the drawer 100 mm less deep. That way the drawer handles will be slightly behind the bench front end, i.e. you don't hit your legs in the handle when working.
Glue and/or screw some leftover protection surface at the front for exclusivity ;)
Fasten the expansion guidings and angle brackets to the drawers.
And, finally, screw the complete drawer unit to the underside of the bench.
The best way to mount the drawings is to have done all mounting of brackets and guidings at the drawers separately, and then fasten everything to the bench. Trying to mount the brackets and guidings first to the bench and later try to fit the drawer on to the guiding will fail. Just trust me on this.
Step 9: The Final Touch (additional)
Screw a ledge to the wall. Looks nice and makes the bench easier to clean without damaging the wall.
Good light is essential for doing a good work. Two roof mounted fluorescent lamps, each with 2x18 W, is sufficient for a 5 m long bench.
I actually prefer to have the power outlets up at the ceiling, if they are possible to reach. Decide where the electrical wirings will be put before building the bench. Otherwise you may have to drill holes in the new bench for wiring. If you are right handed, place the outlets at the right side of your working area, that will keep the cords away from you working.
Of course you need somewhere to put all your working materials at.
Tip: Buy ordinary planks 21x170 mm, screw them together and put them at the walls using angle brackets. Use a small ledge as weight support at the bottom.
If you like music during work, considering design some speaker boxes or use old existing ones, that fit into the shelves. Or integrate them into the shelf. Measure the speaker boxes and make sure of the dimensions needed before building the shelves.