How best to fix down a steam engine
|michael howarth 1||16/07/2020 07:53:02|
|34 forum posts|
On testing my Vospers, fitted with a steam engine, I was forced to review how the engine is "tied down". The link between the 2 cylinder engine and the propshaft is via a universal coupling.... one of those red plastic types. With the engine bolted down firmly there is a significant sort of clicking "knock". This is obviously an alignment problem as the knock disappears if the rear of the engine is raised by about 5mm and I then get smooth running. Experimentally, I have placed a pad of dense foam under the rear of the engine which seems to have the effect of absorbing some vibration. Is this the way to go or should I go for a rigid fixing?
Edited By michael howarth 1 on 16/07/2020 07:53:46
|Malcolm Frary||16/07/2020 09:31:33|
|918 forum posts|
If it is a single joint, alignment needs to be, and stay, perfect. That means having the center lines of the motor and prop shaft intersect at the center of the universal's spider. Anywhere else, something will be trying to realign itself, giving a repeating clonk. A resilient mount might reduce that, but will leave the motor constantly trying to realign itself. Anybodys guess how long before you find out what the weakest point of the mounting is.
A better answer would be to use a double universal or a rubber coupler or a dogbone type.
|Ray Wood 2||16/07/2020 10:10:41|
2164 forum posts
Lots of full-size engineering alignment is based on using shims, aluminum packers would work to loose the knocking ??
|David Marks 1||16/07/2020 13:08:20|
|250 forum posts|
The red plastic coupling (trade name Huco) should be set up so that both halves are on a common axis. To do this I replace the plastic piece with a dummy body (made from aluminium bar) of the same length and bore size so that it accepts the two brass inserts. Once alignment is achieved the dummy body is replaced by the red plastic section.
|michael howarth 1||16/07/2020 20:52:36|
|34 forum posts|
Thank you gents for the valuable advice. Why didn't I think of that alignment method?
Please login to post a reply.
Want the latest issue of Model Boats? Use our magazine locator link to find your nearest stockist!
Make sure you never miss out on the latest news, product reviews and competitions with our free RSS feed
We welcome well written contributions from Website members on almost any aspect of Model Boating with a particular emphasis on practical hints, tips, experience and builds.
In order to maintain a consistent standard and format, all suggestions should first be sent to me by Personal Message for approval in principle. Only a very limited amount of time is available for editing contributions into a suitable format for placing on the website so it is important that the material is well presented, lucid and free from obvious spelling errors. I think it goes without saying that contributions should be illustrated by appropriate photos. I shall be happy to give advice on this.
The Member Contribution area offers space for short informative mini articles which would not normally find a place in Model Boats magazine. It is an opportunity for Website Members to freely share their expertise and experience but I am afraid that virtue is its own reward as there is no budget to offer more material recompense!
I look forward to receiving your suggestions.
Colin Bishop - Website Editor