This particular Instructable isn't so much a step-by-step guide - it's really an overview of the steps I went through to design and manufacture this prototype.  I hope some of you find this useful. 

Step 1: The Brief

I try to scrounge logs for my woodburning stove whenever I can, and frequently end up with odds and ends and awkward sized branches to cut up.  

Cutting these logs up into suitable lengths for storage and burning can be problematic: a chainsaw is needed to do the work, and these are very dangerous tools - more so when the branch you're cutting is no longer attached to a tree!  It's awkward to position a log on the ground (particularly if it's small-ish diameter, and relatively light).  I've seen logs being held in position with one foot while being cut to length - a dangerous idea without chainmail socks!  On top of this, bending to ground level while holding the saw doesn't make a repetitive task like this any easier.

I was considering buying a 'Superjaws' type work clamp with purpose designed log gripping jaws, when I hit upon the idea of using my trusty Black & Decker workmate.  I've used this before to grip small logs (the max opening width is about 130mm / 5"), but maybe I could design something to widen the clamping capacity and offer better grip on the log?  A quick browse around the internet showed that it had been done before and I could buy a set for around £20 - but the only options out there look a bit flimsy, and log size is limited by the travel of the workmate  jaws.  So I decided to design my own. 
<p>I absolutely love this. As an avowed pessimist, I'm always asking what can go wrong. I can only find one flaw that you haven't mentioned, and it may literally be a fatal one: How easy is it for you to catch the edge of one of those jaws with your spinning chain and induce a violent kickback? I think if you cut a section of 1&quot; iron pipe in half lengthwise and welded it vertically down the middle, it would be broad enough to deflect the teeth and prevent them from catching on the jaws. What do you think?</p>
I have been told that I am a danger with my chainsaw and this is exactly what I need for the same job! I'd happily pay for a set if you were up for making some more. I know this is a long shot, but how brilliant and thanks for sharing !
you seem very fond of workmate, it is a clever bit if kit. Just a tip, the plastic corks used in many wine bottles are a great fit for holes in workmate, for steady grip on odd objects etc.
oxy torch with a steady hand plus jig . and uill do fine
i wouldve added slots to where the bends would be at. even if there spaced at 2-3 in.s apart at a length of 1-2 in. long that wouldve allowed u to bend the steel in the correct spots the just weld the gaps closed..
This is really cool. You should create some extras and sell them to people who do not have access to C&amp;C machines and/or welding equipment. AKA... me :)
Would love to get the CAD file for this! Would make a great present for my Father who cuts a lot of logs each winter.
This is nice. I could see using it to make things from a log. Use it to cut odd angles when I'm making porches, stairs, railing, fences, or furniture. But not for making firewood to burn. Cranking in and out those little drive gears would take forever. A sawbuck is so much simpler and easier.
Have uploaded some extra pics to demonstrate this.
It's less tricky than you'd think (and would be easier again if I added a couple more holes), but I'm half in agreement with you about the sawbuck. The disadvantage of a sawbuck for me is that I'd be able to cut very few of the logs I get hold of for free - the crooked awkward to hold ones nobody wants. I'll try to post some more pics over the weekend to explain better. Nice idea about using it for general clamping duties - rustic furniture anyone?
Nicely done. If the posts do come out of the holes then make new ones. For similar situations I've made up what I call wedged dowels, similar to what holds the headset of a bicycle. Drill a dowel lengthwise, cut it lengthwise at an angle. Leave the ends flat. Put the cut sides together and run a bolt with washers and nut through the hole. Put the assemblage in a hole and tighten the nut. Jams in marvelously well.
Step 13: Paint/Powder Coat
Great instructable. Having gone through the problem of steadying logs to cut with a chainsaw, I like your solution. Not having a plasma cutter your design is simple enough to fabricate with other methods.
Nicely done! I love my 20 year old workmate and use it all the time. It's nice to know there's still more things it could be doing! <br>And thanks for going into the detail on the CNC Plasma cutter... interesting and educational.
Is there any chance you would mind sharing the CAD files for these? We have an open fire at home and chainsawing the wood for it is my pet hate due to this exact problem. Thanks!
Brilliant. <br> <br>I like so much about this 'ible - from problem to concept to prototype to roadblock to solution. I especially like how you use cardboard as a mock up. I have more cardboard mock ups than I have finished projects! And even though you used some fancy equipment, there's nothing that couldn't be done with simpler tools. Very instructional. <br> <br>Thanks for sharing your creativity and skills.
Thanks for the positive feedback guys.
You should patent this idea. <br/>Really cool.
The jaws look &quot;mean&quot;! :) <br>Cool and simple solution which adds MUCH security to a otherwise dangerous job. <br>

About This Instructable



Bio: I have a BSc in Industrial Design from Manchester Metropolitan University. I work for a major UK supplier of CAD and CNC systems (almost every ... More »
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