Thursday 18 March 2010

More work on the bench lift

Started work on the other pair of legs. Installed the crush tubes and welded in the cross piece.

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Drilled and welded two bits of box that will hold the lifting bar in place then cut the lifting bar and crossed drilled it. For cross drilling I used a trick I got from the internet to check if the drill was on the centre line. I used a small rule that I held in place with the drill bit, when its level your on the centre line. Funny thing is I've used this method to set lathe tools to centre but never thought about using it for cross drilling.

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Cut a piece of box section to go over the lifting bar and that was pretty much job done for the lifting mechanism.

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Here it is assembled

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I threw everything together to see how it looked (metal for the crush tube hasn't arrived so everything is a bit sloppy at this stage).

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I'm slightly disapointed by the max height available using the cheap jack I have which is why I've lifted it up on planks in the picture above. I might experiment with moving the lifting mechanism (or rather having a couple of positions I can have it).

Sunday 14 March 2010

More on the bike lift...

Swingarm hasn't shown up but I have done some more work on the bike lift.

I already had the parts cut and drilled for the base I just needed to weld them together. I figured that what was important was that the holes that form the pivot were straight and parallel so I used the 5/8" tube that I will be using for crush tubes and a length of 16mm black round to get everything lined up.

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I then held everything together with clamps...

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... and welded one end up.

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Once I measured the other end I realise it had closed up by about a quarter of an inch, which is why I should have tacked everything together before welding. I managed to pull the ends apart by the quarter inch they had closed up and clamp everything together so it all came out in the wash.


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I then installed the crush tubes in the base and two of the legs. At this point I realised that I didn't have enough tube but ebay will sort that out.

The next step was to weld one of the pairs of legs together. I measured the distance between the crush tubes in the base and cut a piece of box section to suit. I also cut opposite corners off the box I'll be using for the legs. This proved to be a bit of a problem on my bandsaw as when cutting at 45 degrees the clamp on the saw cannot hold the work that well and the sawing acrion tends to move the work into the saw which causes the blade to jump off. I did manage to cut them in the end but I had to put the blade on several times. If I have to do more cutting at an angle I'll probably work out a better way of holding the workpiece.

Now all I needed to do was get everything set up for welding. As I had installed the crush tubes I used some 12mm round to hold everything parallel.

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I used the cross piece to check the distance between the two legs at each end then put it in place and tacked everything up. I then checked that nothing had moved while tacking up and did the final welds.

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So as a result of this weekends time in the garage I now have the base and one of the pairs of legs fabricated.

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I'm hoping to get the bench finished before the swingarm arrives... unfortunately I don't think I'm setting myself a tight deadline.