BillinIndiana

I picked up an unknown trainer plane and it needs a motor mount.. I think this one will workhttp://www.amainhobbies.com/product_...or-Mount-40-45

I have a Thunder Tiger GP 42 for an engine.. Here are a few picks of what I have to work with on my project trainer..

da Rock

The Dave Brown mount the link is to has two problems. The holes in the firewall of your model are equi-distant from each other. The front strut on your model projects into where the motor mount will be. The mount in the link doesn't match up to either of those two situations.

The mount you've picked out will probably hold your engine perfectly, but it's top two mounting holes are farther from each other than the bottom two mounting holes are from each other. There is a strong probability the 4 holes in the mount aren't going to line up with the existing 4 holes in the model's firewall. The way the front gear strut is mounted puts metal right where the motor mount needs to go. Even if you cut the excess and worthless strut projecting above the wheel collar, the collar is going to be in the way.

All that said, with some work, the mount can work. Plug the firewall holes and go from there as if the firewall was brand new and needed the new motor mount mounted. Re-think the front gear mounting and redo it.

da Rock

There are motor mounts that include front gear strut support. Will check in the shop to see if I can find one and see who makes it.

BillinIndiana

I took it as the shaft for the nose gear went right up through the motor mount.. I thought I was just suppose to drill a hole in the mount to accomidate the steerible nose gear.. I read this in the features portion of the link I posted

" Mount can be drilled to accept a steerable nose gear – flat on bottom of mount easily allows wheel collars to be used."

red head

I think if you go to Tower and check out the Great Planes adjustable mount that will be what you need . ENJOY !!! RED

da Rock

The one I found probably came in a World Models ARF. It's many years old. It doesn't show up on their website. In any case you'll have to do some work with what you have so..........

What I'd do is use the mount you mention. It's strong and cheap.

You can plug the existing holes in the firewall easily with dowel rod. You want to do that if new holes are needed near the existing ones. The plugs support the new, nearby bolts/nuts/blindnuts and keep them from crushing the firewall. There is also a way to keep from needing the plugs. Fit a new layer of plywood against the back of the present firewall. That isn't a bad idea when extending the life of a used model anyway.

I'd drill a hole in the DB mount where the gear strut excess sticks up. The hole would be larger than the wire. The idea is just to make room. The DB mounts drill easily. It won't be weakened.

I'd then drill mounting holes for the mount and bolt it on. With the reinforced firewall for support the front of the plane is going to be better than original.

The job shouldn't take more than an evening.

biam

I agree with rethinking your front gear also, try removing the plastic mount on top with no screws, move the steering arm to the top of the lower plastic mount and put the wheel collar on the bottom of the lower mount. That is the configuration on my tower trainer. Hope this helps.

BillinIndiana

I think the wheel collar was just put up there to hold everything together.. I see what you're saying. I'm not sure why there are two of the nylon steering mounts, one screwed and one not...? That is just the way it came.
I have so much time in my 1st kit that I bought this as a " trainer before my Trainer" if you get what I mean? This one was only 20 bucks, so I can't complain..

nitro wing

My Feedback: (1)

use the hangar9 mount in your link, middle bottom pic.

BillinIndiana

I was going to go with that, but as my luck is always Bad.. It's out of stock !

da Rock

It's certainly there to hold everything together. It keeps the strut from falling out.

I'd bet the top steering mount was there so the owner didn't lose it before screwing it down. One really isn't very good at keeping the nose gear from folding under. The reason a lot of motor mounts have holes in them for the steering strut is because they really are needed for trainers.

I'm betting that finding a round base mount that would fit the existing holes is going to be tough. It really isn't a big deal to drill new holes. When they aren't near the original holes, it ain't a big deal. The Great Planes motor mounts are square base and have nose gear holes. Their mounting holes are wider apart and would give somewhat more secure support.

da Rock

Not expensive. Sturdy. Has nose gear holes.

I use the larger size for my OS90s. Love 'em. They're easier to use if they are epoxied together first thing. I clamp the engine in place on the beams while the epoxy cures and wind up with a perfect fit for the engine and a one piece mount. It's easier to mark the firewall holes, and drill the beams for the engine hold down screws.

The wide apart nose gear support the mount provides stands up much better than a single little bracket at the edge of the firewall.

http://www3.towerhobbies.com/cgi-bin...&I=LXJ772&P=ML

nitro wing

My Feedback: (1)

I'd probably go with that too.
Get a wood dowel and glue in the firewall holes, sand flush and redrill to suit mount. make sure the thrustline stays the same. (not too high or low) engine crank should be center to hole in firewall.

BillinIndiana

Thanks guys. I went ahead and ordered that Great Planes universal one.. Apologize to my LHS, but I bought it off E-Bay.. I can't drive to my LHS for the $1.98 S/H I was charged..

nitro wing

My Feedback: (1)

good luck and post with questions or updates, you will need some bolts and blind nuts, likely 6/32

to secure engine to mount some use self tapping screws or drill through and use 4-40 and locking nuts, make sure its square and do not force screws into mounts, it can warp the engine casing and be a big problem, and ruin the engine.

gagnomchae

I see what you're saying. I'm not sure why there are two of the nylon steering mounts

JohnBuckner

My Feedback: (1)

Hi Bill I realize I am coming in a bit late and you have already spent the money on one of the 'Adjustables' but I wanted to offer a slightly opposing opinion on mounts per chance some one else may be reading this.

The Dave Brown mounts you linked are in my opinion are for a number of reason a far better way to go and a much easier installation in many cases including your trainer. Also they would have worked well in your airplane even with the large double Dubro gear blocks. only the top of the struts would have had to be trimmed off.


I like the DB's so much that I usually purchase ten or fifteen of them at a time as a selection to always have a selection on the wall and no that for me and I am not a hobby shop.

Ok first the DB's are not adjustable and must be purchased to fit, this soon becomes a hugh advantage compared to the so called adjustables which eats up Hugh acareage on the firewall making for a difficult installation in most cases and looking for perfect square bolt patterns is usually futile.

Now there is a very real and viable reason that the DB's are first round and the bolt pattern is uneven. First the round bas is far more compact and much eaiser it install. It is also easier when some orientations such as ninety or a hundred and thirty five degrees is used. The uneven bolt pattern means for the proper engine that the engine mount can be removed or reinstalled in most every case directly from the front using long drivers something you cannot normally do with the large clumsy adjustables. The Dave Browns will in almost every case work and be an easier installation where conditions are tight.

Do a few DB's and most would not use adjustables ever agine.

John

da Rock

Round works for some people. The square mounts can put their mounting bolts out farther, but think about what that does for the model. The mount is braced farther out toward where the firewall is braced by the sides. A wider base is more stable. Will that additional stability matter? Not for experienced modelers so much. But it's a stronger, more stable design. Whether that will ultimately matter or not.

Do the adjustable mounts pose problems in use? Not if you turn them into one piece mounts right away while you custom fit them to the engine you're going to use.

Bottom line is there are benefits to every mount any LHS sells. Good thing is we got a choice (when they're in stock) and all that have been around for years are still around because they work.

jaka

Hi!
Agree with John! Dave Brown makes the best plastic motor mounts!
Just glue in (CA medium glue and accelerator) some wood dowels in the old holes in the firewall and redrill new ones for the Dave Brown mount!

Lowvoltage

I agree with the Dave Brown mount recommendations.Another mount that Ialso like isHayes. See the linkl

http://www3.towerhobbies.com/cgi-bin...SM&C=GMH&V=HAY