Run along qui­etly now…

Canal Boat - - Insulation -

Unin­su­lated en­gine rooms ra­di­ate more noise and vi­bra­tion than in­su­lated ones – at least that’s the claim. So is it true, and just how easy is it to fit your­self?

Poppy is a 60ft wide­beam built by Louis & Joshua in 2005; she has a 62hp five-cylin­der Beta en­gine on flex­i­ble mounts. The Beta is cooled by a skin tank the length of the en­gine room.

Prior to fit­ting acous­tic in­su­la­tion the noise wasn’t par­tic­u­larly bad, but cruis­ing long dis­tances in Europe, it be­came a pri­or­ity to re­duce noise. I reckon the ideal diesel en­gine is co­cooned, 30ft from the cock­pit, driv­ing a hy­draulic mo­tor be­neath the steerer’s feet. Any­thing else is a com­pro­mise, so we set out to do the best we could with what we had.

Chang­ing the en­gine lo­ca­tion was not an op­tion (ob­vi­ously), so in­su­lat­ing it was the log­i­cal choice. There is a wide se­lec­tion of noise re­duc­tion ma­te­rial avail­able. With­out be­ing a pro­fes­sor of acous­tics, it’s quick and easy to learn that two things need to hap­pen to re­duce noise. Some fre­quen­cies can be ‘re­flected’ back into the en­gine room, while oth­ers re­spond bet­ter to be­ing ‘mopped up’ into a spongy ma­te­rial.

To get the best per­for­mance across the range of fre­quen­cies ra­di­ated by the en­gine, gear­box and pro­pel­ler, we opted for 50mm foam on a hard plas­tic back­plate, with a shiny alu­minium foil fin­ish. The foil re­flects, while the foam ab­sorbs. The hard plas­tic base is coated with a con­tact ad­he­sive. More about that later. We re­jected thin­ner (and cheaper) ma­te­ri­als – hav­ing found quite a few that were 30mm thick – on the as­sump­tion that the thicker it was, the bet­ter. blade, us­ing a short saw­ing mo­tion. As the in­su­la­tion pieces are stuck on, sig­nif­i­cant pres­sure needs to be ap­plied to the ma­te­rial. We used a se­lec­tion of bat­tens of dif­fer­ing lengths to push a piece of ply­wood that com­pressed the in­su­la­tion all over. Fail­ure to ap­ply suf­fi­cient pres­sure re­sults in the in­su­la­tion fall­ing off half an hour later, as we dis­cov­ered to our cost early on.

Fit­ting the in­su­la­tion to the alu­minium en­gine room cover was sim­ple and done in one piece. As soon as the ma­te­rial was stuck down, the cover was turned up­side down on the pon­toon we were moored to, and heavy weights were placed on top.

If a piece of in­su­la­tion does fall off, don’t panic. It’s not ru­ined, but you can’t use the glue as-is. First, re­move all traces of glue residue from the en­gine room us­ing co­pi­ous amounts of white spirit (or what­ever sol­vent is rec­om­mended) and rags. Next, ap­ply spray con­tact ad­he­sive on both the

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.