5 December 2015 - Project Update

On Saturday the 5th of December we played around with the training module once again, the plan was to try out the pneumatic tooling, the tube set-up and expanding/beading techniques.

But firstly, following the initial trial on the training module, a number of items were identified to be obtained prior to giving the real test case a go; no use going full steam ahead if we are stuffing around with 1/2 of the required equipment. The list went like this;

• 3/4 drive to Morse adaptor insert; the new tube rolling equipment mandrels are 3/4 drive and you guessed it, we had every size but..! That's where we get local industry involved and have components manufactured to our specifications. Pressform Engineering manufactured two new adaptors and they work a treat.
• Corking gun - Loaned from a former WAGR boilermaker that happened to still have one in his cupboard, its not what you know but who you know.
• Compressor - When we did the first trial, the volume of air that was available from the small compressor was good but for about 30 seconds, to install the tubes on the S would have taken more time than what's available in our lifetime anyway...! The word went out and Boulder Loopline came to the rescue with their compressor, thankyou.

One of the tasks we wanted to confirm today was the amount of tube projection from the firebox tube plate. I was always told that it should be between 3/16 and 1/4 of an inch but I wanted to confirm a length prior to installing all the tubes into the boiler. This is very important because too little projection runs the risk of damage to the tube plate when beading the tube, too much and there is the risk of poor beading due to excess material.

Drawing showing tube projection and flaring

So we set three tubes up, the first at 4.7625mm (3/16"), the next at 5.5mm and the last at 6.35mm (1/4") and with the use of the pneumatic motor and expanders we expanded and flared all three.We expanded and flared the three tubes at the firebox end first ensuring the projection was what we wanted, we then moved to the smoke box end and expanded the tubes at this end also.


Now for the beading. We purchased several beading tools when we ordered the expanders, we however found that they required a fair bit of shaping as initially they wanted to dig into the tube and cause damage, this took several goes to get right.

Typical beading tool

The Three Amigo's, following beading of the ends.
Note: damage to tube plate on the left and centre tubes due to insufficient
tube projection (4.76 and 5.5mm respectively).
The tube on the right was set at 6.35mm stick-out and beaded nicely.

Close up of the right (good) tube.

Drawing of expanded and beaded tube

We persevered with the small compressor for these three tube which added to the difficulty but never the less we achieved a fair bit today.

The plan for next week is to finalise our techniques and to train (give a go) the members of the team so we all know what is expected on the boiler.