3D Hobby Shop 85" Katana - Assembly Thread

[sukhoi26mx]

On to the engine... I'll be using a DL50, but there are a lot of great options including obviously the DA-50, 3W-50 or 3W 55, BME 50. We've included jigs for the DA and 3W as they're likely the most common.

Using the jig, I marked and drilled the four bolt holes. As is standard throughout the build, use Loctite on all metal to metal hardware.

Scott

[sukhoi26mx]

Mounting up the engine...

Scott

[sukhoi26mx]

All mounted up. I prefer to use large fender washers to help distribute the load on the back of the firewall. On this installation, the motor mount holes are somewhat close to both the top of the motor box and the left side, so you'll likely need to grind the washers slightly to allow clearance.

Scott

[sukhoi26mx]

OK... time for a break. Might as well liven it up a little with a couple more airborne shots...

Scott

[toprudder]

	Quote: Originally Posted by sukhoi26mx
	We know that many new models arrive completely hinged from the factory. This is something we're looking into, but to be honest, is a step that I (personally) almost prefer to do myself to ensure it is done right. Time will tell if we decide to have the factory do this at some point down the road.

Personally, I like not having the hinges already glued. Sometimes I may prefer to use different type hinges, for various reasons (removable rudder, etc). I have no complaints about the quality of the 3DHS stuff, but I do feel good about doing the hinges myself.

Great build thread, Scott. I'm looking forward to getting one for Matt.

Bob R.

[Radioactive]

Scott, and Ben here you go..Nice Pictures
http://www.wirekeeps.com/

Can't wait to get ours..Going Electric... guess i can save a tad of weight on the firewall mod.. what say -'if scott?

[sukhoi26mx]

	Quote: Originally Posted by Radioactive
	Scott, and Ben here you go..Nice Pictures http://www.wirekeeps.com/ Can't wait to get ours..Going Electric... guess i can save a tad of weight on the firewall mod.. what say -'if scott?

Thanks Don! I'll get some ordered up...

Scott

[toprudder]

Is there a particular cannister muffler and header that fits well?

How much distance is between the front of the wing tube and the front bulkhead?

[sukhoi26mx]

	Quote: Originally Posted by toprudder
	Is there a particular cannister muffler and header that fits well? How much distance is between the front of the wing tube and the front bulkhead?

Bob,

Not sure on the can. The spar is above the tunnel, so it doesn't play a factor. The tunnel is roughly (measured while the model is sitting on the ground, me under it trying to get a close number) 63mm tall, and 330 mm long. Ben, I'm sure, can give you a much better idea on the precise dimensions. I haven't and likely won't run a can on this model as noise isn't an issue where I fly and I've gone for simplicity on this airplane.

Ben- exact measurements for Bob?

Scott

[sukhoi26mx]

With the muffler installed, I decided to mount the cowling next. I made a simple template from card stock from the cutout, and went to work with the Dremel cutting disc first, then the sanding drum. My initial thought was to keep the cutout reasonably small, then use the can tunnel as the primary cooling exit. In the end I relieved slightly more cowl for both increased cooling and better access to the needles. Set up as you see in the final photo (down a couple of posts), I can reach both needles without removing the cowling...

Scott

[sukhoi26mx]

Marking and cutting the cowl...

Scott

[sukhoi26mx]

Final cowl cutout. Eventually, I'll add coaming, but for now there she is. I really like the internal fasteners. The cowl ring on this sample is glued well, but be sure to look the glue joints between the ply ring and fiberglass cowl and add adhesive as necessary.

Scott

[sukhoi26mx]

I mounted the ignition off to the side of the engine box with foan padding and Zip-Ties. Access to the forward fuse area is great, so running the zip ties was pretty straight forward...

Also shows a good view of the pin/flag switch.

Scott

[sukhoi26mx]

The DL50 includes a phenolic horn that can be screwed to the short Walbro carb arm, but I decided to mod a Hitec servo arm for that purpose. Simply remove the throttle arm, reverse it so the arm is above the choke arm, drill and attach the Hitec arm, and attach with a 2mm screw and but. I also used Loctite to secure both the throttle screw and the secondary attach hardware for the second arm.

Scott

[sukhoi26mx]

Reinstalled, reversed, lengthened servo arm. This will provide good access for the throttle servo away from the choke arm.

Scott