Tuesday, March 3, 2015

Rolling lift bridges of the world - 2

Imagine my surprise on arriving at Hobart to find a rolling lift bridge almost identical to the one in Auckland harbour.  In Auckland I had no idea how the bridge worked but this time I had a basic understanding so I made an effort to photograph the important details.

Side elevation showing the concrete counterbalance in the elevated position.

The drive shaft and pinion.

The rolling rack mechanism.

The photo of the steam crane is gratuitous.

Saturday, February 14, 2015

The Steam Yacht Preana

Riding in the luxurious saloon of the steam yacht Preana is not the boating experience I am used to.  For me it was almost claustrophobic but a fascinating opportunity to see a steam launch in action.  The boat was originally commissioned in 1896 by wealthy Tasmanian flour miller and parliamentarian William Gibson.  She is a 55 foot launch originally powered by a 60hp triple expansion engine but has been restored and fitted with a 40hp E compound engine from 1905.

Thursday, February 12, 2015

The Yukon of Copenhagen

My personal favorite of the Hobart festival was the Yukon of Copenhagen.

A Danish fishing ketch she was bought, as a wreck, for a case of beer and then rebuilt with Danish oak and Swedish pine.  As luck would have it she is now for sale so if I had a spare $490,000 I would consider buying her.  The Yukon web site shows her as 17 meters but the boat sales site says 24 meters so I guess she is between 17 and 24 meters.  I enjoyed hearing her story from the captain but I didn't think to ask how a Danish vessel got the name Yukon.

Hopefully I'll get another chance to get on board and ask.




Monday, February 9, 2015

Hobart Wooden Boat Festival 2015

Im back from three days in Hobart with enough photos to keep blogging for another twelve months.  It would be a tough call to name the prettiest boat in the festival but this Herreshoff pram would be a contender.

Saturday, January 24, 2015

Bean rock lighthouse.

I am back from NZ now and and getting back to normal life.  I had a lot of time in Auckland to watch you tube instructional videos and practice my drafting skills.  I had a crack at drawing the bean rock light house with Rangitoto in the background.  The lighthouse was erected in 1871 as a response to increased shipping servicing the gold rush and is an Auckland icon.

The other memento from my trip is a copy of The Dinghy Cruising Companion by Roger Barnes.  I enjoyed read his collection of articles about boats and sailing.  Stories of his sailing misadventures probably wouldn't entice a novice into dinghy cruising but if you are already a wooden boat tragic they are a good read.  I was most interested in the details of his Francois Vivier designed Ilur and the amount of electronics he has packed into a 15 foot open boat.

Friday, January 9, 2015

Auckland's rolling lift draw bridge

I recently came across Auckland's rolling lift draw bridge, which I have seen before, but have not paid any attention to.  This time I noticed a gear rack embedded in the road way and took a couple of photos to try to understand how it works,  This particular bridge was supplied by the Cleveland Bridge and Engineering Company in 1932 but it seems the rolling lift design originated by William Scherzer who died in 1893.  The drive pinion retracts the bridge along the rack located on top of two frames anchored to the bridge abutment.  Two curved edges at the end of the bridge truss are engaged with the gear racks embedded in the road and the whole structure rolls up and back out of the way of passing boats.

I had to make a paper prototype model to illustrate and understand the mechanism because I haven't seen the bridge working.  Notice how the pinion stays at the same level as the drive motor and gear train revolve around it.  William Scherzer gets my vote for induction into the Tinker's Hall of Fame.

Saturday, December 13, 2014

2B or not 2B

After being banished to Melbourne's western suburbs for most of the year I am now holed up in Auckland on family duties.  2014 is looking like  the year without tinkering.  After my last post I had a kind offer from Greg Merritt (https://gregmerritt.wordpress.com/) to use his knot tying illustrations but the thought occurred to me that I should be producing my own drawings. I am probably one of the last generations of engineers who has spent time at the drawing board with a pencil and paper so I should be able to produce a usable instructional drawing.
The interesting part of the exercise was realising that I really needed to illustrate hand positions as well as rope.  Not something they covered in engineering drafting 101 in 1985.  The other interesting point was just how difficult it was to communicate the sequence and details of operations so the Mrs Tinkerer could follow.
2015 could be the year to improve my drawing skills.