Folding Saw Bench Plans
Safety Notice
These plans are for a prototype saw bench. A production model would require further work
to design an efficient guard to protect the user or any other person from inadvertent
contact with the saw blade.
The frame and operating handle must be properly earthed.
Suitable protective clothing and equipment should be worn at all times when operating or
working near the saw.
Copyright � 2012 John Gelling
www.johngelling.co.uk
Parts List
To complete the basic saw bench, you will need 8m of 40mm x 40mm x 2mm steel tube,
1m of 20mm x 5mm flat steel bar, one 800mm x 360mm sheet of 1mm steel sheet, and
two 75mm M8 bolts with lock nuts.
Other pieces of steel and sundry items will be required to make the pivoting saw cradle.
An electric chainsaw, relay, switch etc. are also required to complete the project.
Qty Length Material Details
2 1000mm 40 x 40 x 2 tube 90�; 60� end cuts
4 750mm 40 x 40 x 2 tube 90�; 90� end cuts
2 200mm 40 x 40 x 2 tube 90�; 90� end cuts
2 800mm 40 x 40 x 2 tube 60�; 60� end cuts
4 125mm 20 x 5 flat bar 90�; 90� end cuts
1 800mm x 360 mm 1mm sheet steel 90� fold along longest centre line
2 75mm M8 bolts
2 M8 locknuts
Operating the saw
The saw is turned on by pressing a push button on the right side of the operating handle.
The saw stops when the button is released. The operating handle is held by the left hand,
the button is conveniently pushed using the left thumb. The user's right hand is furthest
from the bar and should be used to hold logs in place while cutting. Gently pulling down
on the operating bar will cut through several branches at one time.
The weight of the saw ensures that the bar always remains in the upright position while
logs are pushed along ready for the next cut.
Main Frame
The steel should be laid out on a flat surface, joints clamped before tack welding into
place. Check that all joints are square before full welding.
Front and side view of main frame (third angle projection)
Note: the bottom ends of the uprights are cut at 60� as shown below. This is so that the
feet will rest squarely on the ground.
Main frame assembled
Support Frame
In the same manner as above, weld the parts of the support frame together as shown
below.
Support frame front and side view (third angle projection)
In this case, both the top and bottom of the uprights are cut at 60�.
Joining brackets
Cut four 135mm lengths of 20mm x 5mm bar and drill an 8mm hole 10mm from one end of
each length as shown.
These should be bolted on each side of
the uprights of the main frame. Now bring
the main frame and support frame
together as shown below and clamp the
joining brackets in a horizontal position
each side of the support frame before
welding in place.
The final part of assembling the basic bench is welding the log support in place. A sheet of
1mm thick steel measuring 800mm x 360mm should be folded by 90� along it's longest
centre line (a blacksmith or sheet metal worker will usually do this for a small fee). This
can then be dropped into the top of the trestle and skip welded in place. It may be
necessary to grind off some of your previous welds to enable the log support to sit snugly.
That is the basic bench complete. Plates should be welded to the bottom of the legs to
prevent them from sinking into soft ground and filling with mud. You could also weld plates
to any other open ends; I used plastic plugs which all got knocked off and lost!
Mounting the saw
I have not included detailed instructions on how to mount the saw, partly because each
chainsaw is different, but also because my method of pivoting the saw about a point above
the bar is not ideal. It would be better to make a cradle that pivots as near to the centre
line of the bar as possible. This is left to your own ingenuity...
These photos show the mounting I used. The saw is
attached using the two bolts which attach the body of
the saw to the bar. This has worked very well during
many hours of use.
Modifications to the Saw
The chainsaw had a drum brake operated both by the hand guard, and by releasing the
trigger. The trigger mechanism and brake were completely removed in the prototype.
Conclusion
The saw is efficient at cutting a number of logs simultaneously. There is very little physical
effort needed to operate the saw. As the bar cuts down into the log support and the chain
pulls towards the back of it, the logs are easily held in place.
Safety could be improved by adding a guard, however the positioning of the operating
handle which allows the user to stand to one side of the blade, the fact that logs can easily
be held in place, and that operator fatigue is negligable, probably makes it safer than using
a regular chainsaw to cut small branches.