Sound in my brass 2-6-6-2 is progressing - I think. I have a 1" speaker that just nicely fits after being set in a plastic sound chamber.
Question - Will this work? Can I drill a group of 1/8 inch holes in the bottom of the tender and then super glue the speaker directly on top of the holes?
This is a fun project, but it reminds me how much of what I learned 25 years ago, is irrelevant today.
i wouldn’t glue the speaker directly to the tender unless the speaker has some extra depth on the frame around the actual ‘cone’ so the cone doesn’t touch the tender when it vibrates . that would give a buzzing sound , or at least some distrotion
here’s what i did with my spectrum 4-6-0 (plastic , but the theory is the same)
http://www.trains.com/community/forum/topic.asp?TOPIC_ID=59242
you can see i glued the speaker bezel to the bottom of the tender and used the body of the tender as the speaker enclosure .
I could be wrong but I think what Art meant was glue the sound chamber to the tender. Ereimer is correct in what he says though, you need room for the speaker cone to move, both Top And Bottom. Drill away, Art but I would go with a larger hole size. Just be careful though. It would probably be wise to step up rather than start out with a huge (relatively) size drill. Start with something about half the size you want to end up with, secure the tender floor so the drill doesn’t catch it and turn it into an airplane propeller, take your time, and make sure your drill bits are sharp…
I agree with the above…make darned sure the tender is firmly secured before applying the bit, and do use a small bit to start ALL of the holes. You’ll need about 20 holes in the 1/16" - 3/32" size, so you’ll have to be patient.
Also, I would not glue the sound baffle to anything but the speaker edge, itself. Then, I would place something soft between the speaker and the tender shell to minimize the tearing sounds that might emanate otherwise. The speaker and baffle assembly should be held securely by cotton ball pieces, or something, so that it doesn’t rattle around, but it should all be free to vibrate to produce good sound quality. Just try to keep the mouth of the baffle close to , and oriented to, the holes that you drill.
My BLI Niagara tender has the speaker lying on its side on the tender frame, believe it or not, and facing the engine. It works, but the horn seems raspy, so I sent it back. All other sounds seemed fine, and had the requisite volumes.
Drilling holes in the brass is no problem; I have two tenders like that from the factory. I would also use silicone adhesive to glue the speaker mount in place as opposed to super glue.
[#ditto][#ditto][#ditto] Bingo! Thats how ya do it!!!
I put a Tsunami with a 28x40 mm speaker the tender of my brass SP 4-8-2. It’s a Vanderbilt style oil tender so I had no choice but to drill some holes in the floor, which isn’t very wide because of the tender design. I only have maybe six or eight holes about 1/8 inch in size or less, but the sound is great.
The speaker is just shoved up inside the oil bunker facing down in a custom enclosure I built myself. There’s nothing really holding it there except friction and the fact that it’s too big to fall out (getting it in was fun). The Tsunami itself lives in the rear of the tender.
I put a Soundtrax DSD-B280LC decoder in my Bachman HO 2-8-0. Works great!! The instructions say to drill 1/8" holes in the sub base for the coal load. One can get about 30 or so holes ,then to drill 100 or so No. 55 holes in the coal load itself. Which is plastic. As it turned out the tiny holes are all but invisible, you really gotta look to see em. The sound comes out great. You might consider using double sided foam tape to mount your speaker box with no danger of vibration. Sometimes the acetic acid in silicone sealers can play hob with your electronics as we found out when trying to waterproof our R/C planes for float operations.