wizzinbya

I am not a newbie to electrics or glow but due to failing health I am converting most of my glow to electric. The problem lies with the mounting of an electric motor on the hardwood rails found in the engine compartment in most of my planes. There has got to be someone making motor mounts for rail mounting other than the firewall bulkhead type. What the heck, all my glow motors have rail type mounting tabs, am I the only one who sees this as a legitimate question. Do I have to engineer a mounting system myself or has someone else addressed this problem. Thanks, Wizzinbya

gosch

I did a 4 star 40 used a Mega 22-30-4 and it worked great. The megs is a 30 mm and fits great between the hard wood rails. The mega is an inrunner with 11/8 prop. The plane takes off with 1/2 throttle. If you jam the throttle it will (ground) flight loop because of the P factor. In the air there is more then enough power and if you use good throttle management you will fly for at lease 12 minutes on a 4 cell 4000 pack.

tIANci

You can also use an inrunner with a plenary gearbox.

wizzinbya

I may not have made myself clear on this topic in my earlier post...Are there motor mounts and or brackets available that would allow for a bolt on conversion of electric motor to the existing engine rails?

tIANci

Wizz ... I think what we meant is to use inrunners and then a clamshell to mount the motor to the rail mounts. Something like this ... you can try [link=http://www.espritmodel.com]Clamshell mounts[/link]

wizzinbya

Hi, Thanks for the response...the clam shells would work on Inrunners just fine, has anyone designed a bracket that would basically mount on front of Outrunner and transverse around to the sides and allow rail mounting? The main problem I have is that most of the firewalls on my planes weren't designed for mounting to them. Thanks, John

tIANci

John ... I know what you mean. Not seen any yet. Most of the hobbyist cut the rails off or they build a secondary firewall into the rails. A lot of work I must say ...

wizzinbya

Thanks for the info...that's what I thought. Now I am thinking about modifying one of those glass filled motor mounts with the round ring mount towards firewall and turn it around and use it backwards and mount the X type mounts to the round part facing forward. Maybe you have seen those type mounts. Am I making myself clear enough. I think if I find the right mount, it might work. John

wizzinbya

Something like this:[img][/img]

tIANci

John ... this is that I do for tail draggers and for trikes ...

wizzinbya

I will see how much work it would be to remove rails and beef up firewall! Thanks for all the input. What type of motors are you using? John

tIANci

I have used AXI, Hyperion, DualSky, Plettenberg, Turnigy and a few more. Hence from decent brands to El Cheapos. The AXI is not bad and the Hyperion is very sweet. The DS motors are cheap and they work fine for the smaller ones, up to 4260 series. I tried the 6360 and its kinda rough to me and feel under powered, maybe its inefficient. For the above planes it was the Dual Sky 4260-680KV on 5S, kinda hot with a 12x10 prop but you are talking really unlimited verticals.

wizzinbya

Hi, I found something similar to what I was thinking of but it is for small motors. Looks like I will be doing some cutting and filing of alum extrusion. John[img][/img]

leiffk

I am just converting an old stick with rails mounting( 20 years old) to electric. I just took a piece of 16 gauge aluminum and made 2 half shelves. Works dandy for an old new dc motor. For a outrunner is is a little complicated

Glacier Girl

My Feedback: (4)

Here you go Wizz. I think I know what you were getting at. I too had to come up with my own way of doing it. Wasn't hard at all. Drill and tap the front of the gas mount. Piece of aluminum plate, drilled for motor mount bolts, shaft, and gas mount bolts. Just to be on the safe side, you could drill all the way thru the gas mount into the firewall and either use blind or regular nuts. Not pretty, but worked fine for outrunners. I could have easily dressed them up, but they were covered up by the cowls.

These were on a 90" P38, spinning 16" 3 blades.

speedy72vega

Glacier, that is an excellent idea! I just converted a 63" Extra 330L to electric, but I cut the mount rails off and used an electric motor adjustable mount kit. The one concern I see with the examples given are that you would need to make sure that the motor shaft center line is the same as where the gas/nitro engine crankshaft center line would be to avoid thrust issues and cowl clearance issues.

Here's a pic of my conversion. It requires a little work with a coping saw and construction of a new firewall (at least on my plane it did) with enough cooling holes to keep the ESC and motor cool, but it sure worked perfect.

Glacier Girl

My Feedback: (4)

Speedy, yep took a little measuring to make em right. Note the block the mounts are on. I cut em on my band saw to get the correct angles and lengths. Drilled to match the stock nut locations, epoxied them on and used longer bolts.

Now it's easier to use the bolts/spacer set ups like tAINci showed. On most of these gasser converts the firewall is already strong enough for an electric as they were designed for a vibration gasser.  Four bolts and some nylon spacers and you're good to go. Not as pretty as yours, but still works.  Ok that and the bolts and a handful of spacers from Lowes/Home Depot are cheaper then a built mount, and take a lot less time then and crafting one.

speedy72vega

I love the idea of going right to the end of the mount like you did, but unfortunately in my case that wasn't an option. The plywood had the gas mount built right in, it wasn't a surface mount like the one in ur pics. i will say though, the pre-fab aluminum mount I used was only $9.95, pretty reasonable.

speedy72vega

Oops, forgot to add. Another reason I had to make another firewall was the stock one had vent holes right where I needed to attach the motor mount. Iattached the new firewall to the existing one with epoxy and screws/nuts, and then attached the mount to my new firewall.