Convertion of Thunder tiger trainer from IC to electric

[Basil]

I have just bought a second hand Tiger Trainer, with an OS40 ic engine.

I would like to convert to electric. George at 4max has suggested the motor , ESC and Lipo size, now for the change over to commence.

What procedure should I carry out?. What should I look out for.

I would also like to hear from anyone who has done this or bought the later electric powered version on what is fitted as standard etc.

Thanks in advance, Barry

[Allan Bennett]

George at 4max has a good reputation for getting power trains right.

Things you need to think about before you start your conversion are:

• The electric motor will invariably be shorter than the glow engine it's replacing, so to get the prop in the same position the motor will have to be mounted further forward than the glow engine was. This can be done by using stand-offs (long bolts with tubular spacers on them) to mount the motor on the existing firewall.
• In most cases the battery will need to be as far forward as possible in order to get the model's c. of g. in the right place without the need to add lead to the nose, and it needs to be easily accessible for connecting and disconnecting. Often the simplest location is where the fuel tank used to be, with access by removing the wing. Not ideal if you need to disconnect quickly, so a removable battery hatch in the top of the model is desirable.

On several of the many models I've converted I've constructed a battery box that goes through the original firewall, extending as far enough forward as is necessary to get the prop in the right position when the motor's mounted on the front of it, and extending as far back as the second frame member (usually the rear of the fuel tank bay) for support. I make the battery box out of liteply, with a 6mm ply front end for mounting the motor. The extra structure of the battery box makes it safe to cut a large opening in the top of the fuel tank bay for access to the battery. By taking advantage of the ability to get some of the battery forward of the original firewall I've rarely had to add lead, and all my electric conversions have ended up slightly lighter than when they were glow-powered.

I hope that gets you started.

[Basil]

Allen, thank you for your reply, I was begining to think that my entry had been overlooked by every one.

I will be examining the airframe in order to apply your reccomendations, and maybe coming back to you. Thank you once again. I've already thought about side/down thrust. The current IC is pointing to the left( When viewed from back towards front)surely thats wrong!!. Should I apply some side/down or just install ILW the airframe?

Barry

Edited By Basil on 25/09/2020 08:24:29

[Peter Miller]

I can second Allan's method. I used a very similar one when converting my Ballerina.

Bearing im mind that the electric motor is a lot lighte than the i.c. engine one can accept some lead if needed.

[Former Member]

[This posting has been removed]

[Allan Bennett]

Posted by Basil on 25/09/2020 08:10:00:

Allen, thank you for your reply, I was begining to think that my entry had been overlooked by every one.

I will be examining the airframe in order to apply your reccomendations, and maybe coming back to you. Thank you once again. I've already thought about side/down thrust. The current IC is pointing to the left( When viewed from back towards front)surely thats wrong!!. Should I apply some side/down or just install ILW the airframe?

Barry

Edited By Basil on 25/09/2020 08:24:29

The airframe doesn't know what the source of the power is, so down/side thrust should be the same with electric as it was with glow -- generally down and right for a normal prop rotation.