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:
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:
Total cost for 4.8 m x 2.0 m (in Swedish Krona, SEK):
Total cost in USD: 2486 SEK => 380 USD (Feb 2014: USDSEK = 6.55)
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...