I am a 42 year old RC virgin so please bear with me while I ask some rookie questions. A buddy gave me a Tower Hobbies Trainer 40. It's almost completed but I have no idea how to mount the engine. According to the plans there is what appears to be a pair of straps that hold the engine to the mount. They are nowhere to be found. The holes on the Tower Hobbies 40 engine do not match the holes on the engine mount so I guess I can not just direct mount it. Can someone please advise me as to how I should do this? Thanks for any help. dc

As soon as I get this question answered I'll undoubtedly have some more........

I'm not familiar with that particular kit so I'm just guessing on the mounting system it uses.

If the holes in the engine mount are far enough apart that the engine's mounting lug can sit neatly between the holes then use something like a 1/8" alloy strap to clamp the lug to the engine mount. Another way of course is to reposition the engine slightly and just redrill holes to suit.

The simplest and safest way would be to go to the hobby shop and get a new mount. Should only be roughly 5 bucks or so. Just mount it to your firewall , drill it and mount your engine. The strap hold down mount you described aren't that impressive. They tend to slip on rough landings and your engine in now out of alignment.
Keep it simple for yourself.
Al

In the event you have to drill holes for mounting there are a few methods you can use to mount the engine with. You could use the device that great planes sales, for finding the holes, not sure whats its called. There are different other tricks you can use as well. The method I use is a click pencil I stick in down inside the holes mark my holes then use a center punch being careful to hit the very center of the hole then I use a drill and tap to thread the holes. Where you place the engine on the mount could effect your CG (center of Gravity) but its better to have a nose heavy plane rather then a tail heavy so you might want to mount it with in around 1/4 - 1/2 inch of the very front of the mount.

Randy

2 More scentz....

If you use bolts to fasten the engine, get bolts long enough to extend through the mounts and install jamb nuts to keep them from working back out from vibration ect..
It is neccesary to go over all your connections regularly to ensure tautness, but I have forgotten to remember to do that before and nearly lost a fairly good engine.

Roger

I set the engine, with the prop and spinner mounted, on the engine mount. Then try to balance the plane. Sometimes a small drop of thick ca glue is helpful in keeping the engine where you put it. Remember to account for down and right thrust angles as per the instructions. Some planes have these angles built into the firewall, some give instructions how much of each to use and if you're lucky, they will give some insight as to how to accomplish this. From there, I saw a post earlier that suggested using a tool that I think is called a dead center engine mount locater from again I think, great planes. It has a small cone with a small drill bit that protrudes from the center of it. I don't know how I got along without mine. They are not much $. If you need to re-fit a new mount to the firewall, again try a small drop of thick ca glue on each side to glue the engine to the mount temporarily. and use the tool described above. You can plug the old mounting holes with dowels glued in the holes with either epoxy, or slow ca. Cut and sand dowels flush with the firewall, then re- drill and insert blind nuts. Don't forget to use lock-tight on all bolts. I would use locknut's with the neoprene inserts if possible.

after reading these post and if still confused ,then carry the plane to your club or hobby shop,on some planes the mounting system is built into the plane which makes it hard to change the mounts, on your plane think you can set the engine on the mount,mark and drill the mount then install srcews with lock nuts,make sure the engine points stright or a tad to the right,2 degrees,not to the left.
Have a goodun,John.

DCinLinnCo,
The Tower Trainer you are building is the same one that I learned to fly with, and still have hanging in my garage so I can use it instruct with. I have 200+ flights on this plane, so I'm pretty familiar with the entire plane in general.

You are correct about the engine mounts. The holes drilled in the mount are there to use a strap of metal to bolt down the engine. If those straps are missing, you can replace them fairly easily by visiting your local hardware store. you need two straps of metal long enough to extend between the pre-drilled holes in the mount and 4 bolts/nuts long enough to extend through the mount. to mount the engine you place the engine on the mount and then fasten it in place by putting the straps of metal over the engine's mounting lugs. then use the bolts to tighten down straps to hold down the engine. Make sure you get self locking nuts, or use thread lock to make sure the nuts don't loosen and fall off due to engine vibration.

I prefer to use the strap system of engine mounting on a trainer as opposed to drilling the mount and directly bolting the engine on. This way you can experiment around a bit to see the effects of engine thrust on your plane. Just another use of a trainer, to teach you the different effects on engine thrust.

I've snapped a quick pic of my trainer so you can see how the mount should look.

Hope this helps.

Wow....thanks everyone for your responses. I truly appreciate the advice. RCKen...your setup is exactly what it calls for. Beings I am such a novice and wanting to do things " by the book" I went ahead and ordered another mount just so I can use the straps and hardware. I 'll be able to use the mount itself some other time on another plane I'm sure so it's not totally money wasted. I'll be able to use the "buy the straps at a hardware store" the next time once I see what they look like. Once again thanks for the help. It is greatly appreciated. dc

you are most definately welcome. that's the great thing about a place like RCUniverse, and this hobby in general. We're all here to help each other.