70cc PAU Extra 300SP build...

[Jetpainter]

Terry, is that the Spektrum 9020 reciever? I've been using a couple of those for a few years, and they've been great, but the stacked plug configuration and the way it's labeled drives me insane at times. They need a big arrow for me that says 'This row numbnuts"

 

[Terryscustom]

Terry, is that the Spektrum 9020 reciever? I've been using a couple of those for a few years, and they've been great, but the stacked plug configuration and the way it's labeled drives me insane at times. They need a big arrow for me that says 'This row numbnuts"

Yes, it is funny that it has a label on both sides and the labels are just opposite. They are a great RX though, and paired with a batt share switch they work amazing for this size plane.

 

[Xpress]

Terry, is it done yet?!?!

 

[Terryscustom]

Terry, is it done yet?!?!

Sorry, not quite, just getting back to work on it today. I will likely get it mostly done on Saturday / Sunday. Working on hinging right now, will have a few more pics tonight.

 

[Terryscustom]

I spent quite a bit of time on the covering since there is a lot of covering over top of covering I used a fresh xacto knife to pop the little bubbles and smooth them out. Came out great!

**TIP! - here is one not many people know about.... Ever have your plane out in the sun and your ailerons are all puffed up, then take it home and the covering is all wrinkled? Or you have one spot that is wrinkled and as soon as you heat it the aileron puffs up and the whole thing gets wrinkled?? Here is what you do - Take a 1/16" drill bit and drill a single hole in the bottom of the rudder, root side of the ailerons and elevators. No more pressurized surfaces!!

I hinged with 30 minute epoxy, to lube the hinges I like to melt some petroleum jelly and dip the hing point into it from both sides, place on towel so it does not run on the part that gets glue.

Time to mount the engine! If you are putting a DA70 in this plane you will need 1 1/8" engine standoffs. Little measuring and marking, drilling and I installed with 6mm bolts, SWB standoffs, fender washers (don't use standard size washers behind the firewall!!!) and nylock nuts.

**TIP-2 - For ANY ARF assembly, make sure to chase ALL blind nuts with a tap before installing a bolt!!! China blind nuts are stamped so sometimes they need a little chaser to clean them up. Also sometimes glue can get in there during assembly at the factory.

Next I pinned the firewall by drilling small holes, harden with CA and install servo screws.

I decided to use the stock tail wheel, it is a perfect size for this plane, no problems rubbing the rudder when harriering on the deck. The little screws for assembling the tiller arm to the rudder are fine, but a little small so I like to use 7/16" servo screws. For springs I buy them from McMaster Carr and install them with some fishing line swivels, either #2 or #3 in size. Quick, easy and nice if you need to service them.

Gear is installed. Stock wheels are just fine, but I fly on a LOT of different fields so I prefer a 4" wheel on this size plane. I will put the gear cuffs on later, I just bolted the wheels on in case I need to get the plane off the stand for any reason. I'll install the cuffs and pants towards the end.

NOTE: I am getting asked this a few times, and YES I can confirm that the DA70 fits in this cowl with a solid 1/4" of space from the plug cap to the inside of the cowl

 

[Flyfalcons]

The 50cc Extra is one of my all-time favorites. I absolutely love mine.

 

[yakken]

Nice plane stand you have there. Who makes them.[emoji12]

 

[Terryscustom]

Nice plane stand you have there. Who makes them.[emoji12]

Some dude on the internet

 

[Jetpainter]

Some dude on the internet

You gota watch those guys, there's some pretty shady dudes on the interwebs.

 

[Terryscustom]

Engine compartment and cowl complete, all buttoned up!
- I made a new arm to solve the issue of the carb arm pointed towards the firewall and interference with the muffler.
- Next up was cowl installation and cutting. I determined if I take 1/2" off the mufflers and angle the stacks at 14 degrees I can get the cowl on without cutting a huge slot in the bottom. (y)
- Next was throttle servo, I used an MKS 1250 with a .75" arm. I determined where I wanted it for good linkage geometry and cut the hole, installed some blocks on the inside for screws and support. Pushrod made from stainless 4-40 all thread, sleeved with carbon.
- Next is baffling. I get asked quite a bit and see it asked online quite a bit...."do I need to baffle". Short answer, YES!!! You'll be rewarded with a cooler running engine, more power and a longer life out of your engine. I did this one with creative foam (or the similar material I got from Amazon). Install with medium CA and I hit the corners inside with "goop".