Trevithick Boiler Feed Pump, and a base.
Quite a few potential workshop days are being foregone because we in southern Oz are experiencing a very hot summer. And the few more moderate temperature days are “lost” to essential jobs for SWMBO, and around the house. Shouldn’t complain about the weather. Townsville, Queensland, where my brother and family lives, has been declared a disaster area due to torrential floods… 1000mm (39″) rain in the last few days, with more on the way. And the next ice age has apparently started in USA.
But, back to the workshop for a few hours here and there, I have made the boiler water feed pump for the Trevithick dredger engine. As usual, I grossly underestimated the time these few simple components would take to make.
The pump is driven off the crossbar where the stroke is 100mm (4″). At the pump, the stroke is ~17mm (~5/8″). The suction side has an 8mm (stainless steel) non return ball valve and the delivery has a 6mm non return SS ball valve. The plans specified a dummy pump, for appearance only, but I have made it functional.
The 2mm ss cap screw is to limit the ball movement to 0.8mm travel. Something less conspicuous will replace the cap screw. Probably a ss grub screw.
The rod driving the pump piston is a piece of bronze brazing filler rod. Just happened to be the correct diameter.
I will need to add a further pump, hidden somewhere, for boiler approval. It will probably be a hand pump.
The next step is to design and make the stand for the engine. The plans specify a large, and in my opinion – ugly, wooden box. So that is not on my option list.
Most of these “dredger” engines were used in factories and mills. Some were used to drive mine pumps, and a few were used on dredgers. In the factories and mills they would have sat on masonry or wooden bases, and on the dredgers they would have sat on the very solid decks. (the dredgers in some cases were converted gun ships, designed to mount large black powder cannons, mortars or seige guns, so they were very solid!)
Now, some pictures of other dredger engine models, and the reconstructed full size one, and their bases. I have numbered the pictures, and I would be interested in my readers opinion about which would best suit my model. Please leave a comment.
John #2 and #6 but thats just my liking , you have a much better eye than me
Very hot here in Yass too John.
The Aldi fan just stirs the soup.
As you’ve asked, here’s my two bob’s worth re the base.
1. Make no attempt to continue the engines historical theme and let it speak for itself on a simple elegant base which serves as a base but does not distract us from the star of the show.
2. Continue the historical theme much as you have in pic #2.
Seeing that you will be running the engine on steam and I assume sometimes in public, I would opt for #2.
It’s a personal thing and either way it’s a credit to you.
Need a bit of thought before I can proffer an opinion. At the moment, I’m just blown away by your craftsmanship, artistry and attention to detail!
I will appreciate your opinion Richard..
Definitely number 4 in my view.Having seen the photo,s of the sideboard you have made,you would do the engine justice with a lovely Huon pine piece,a resourceful fellow like yourself should be able to find some.
On another note,I too always look forward to reading your progress reports,so please keep up the good work.cheers
Thanks Neil. Taken on board.