Juice

BBowen... I have Robart RoboStruts and 4" wheels on mine. I used two HS-75BB retract servos with 113 oz-in of torque each (just in case). I didn't have problems with torque. The rod connecting the servo arm to the bellcrank was the weak point. When retracting, the servos push the rod out and they would start bowing instead of lifting the struts and wheels. I swapped out the original rods and replaced them with 4-40 sized rods. I've had no problems after that.

Nice setup up front, by the way.

Juice

Whistling Death

Yea I kinda thought the rods were weak. I just got a pack of 4-40 rods so I am going to change them. I wish I had some carbon rods.

LDM

My Feedback: (15)

If you go to two servos and oleo struts are you approaching the cost of air retracts ? Not a critsisum just a comparision , but CJ runs about $219 plus deals from Tower , Robart $139 for the 615 , plus deal from Tower ,
how expensive are two good retract servos packing 113oz of Tor, each ?

Whistling Death

75BBs are $29.99 each. Robostruts are $37.99 each. 4" Robart scale wheels $15.49 = $121.46

I have the one JR servo which is $60.00 and the VQ struts $40.00 a pair. 3.25" for $12.99 = $112.99

If my corsair lasts a while I will eventually put air retracts on it.

LDM

My Feedback: (15)

Hey BB good news , now the VQ are $25 a pair from hobby people !!!!!

Whistling Death

I changed the push rod to 4-40 and they still suck. I guess I have some CJ's in my future.

LDM

My Feedback: (15)

Check on ebay , if you get luckey you can get a pair of the CJ rotators for around $180 , or tower has the best price

Juice

LDM... The Robostruts were salvaged from my crashed TF Corsair. I didn't want to use the Robart #615 retracts again, so I just re-used the struts on the mechanical retracts. I didn't know if one regular torque retract servo would be enough to lift those struts, and my LHS didn't have any high torque retract servos at that time, so I thought I could put in two regular retract servos instead. I worked out pretty good.

BBOwen... I made every effort to remove as much slop as possible from the retract linkage. This helped a lot. I used slop-free swivel links on the retract servo arms and heavy duty Du-Bro clevises on both sides of the bell-crank. I can take pictures of the setup later today, if you're interested in seeing it.

Juice

LDM

My Feedback: (15)

Juice I am , please do

Whistling Death

Ok, I tweaked them a little bit. I loosened the allen screws on both ends of the push rods and moved them in about 3/8". this has helped greatly!. They retract all the way up now. I still don't like the way this system works. I may do what Craig-RCU did and mount a servo right next to the gear. That takes the long rod and the belcrank out of the equation.

Really what I want to do is order another wing and fix the retracts and install flaps. But for now I am tired of waiting, I want to fly this bird. Hopefully I can maiden it this weekend. I hope my RCV 90SP doesn't rip the firewall out I have 2 other planes I am building at the same time and I want to get them done as well.

LDM

My Feedback: (15)

I have CJ gear in the box , my goal was to simply see if I could use stock gear with struts just like so many have claimed all over RCU , perhaps its another urban legend so famous in the RC community ???
Ok just kidding , I will try the 4-40 when I am ready to build corsair #3 waiting in the box in my hanger , worse case is all I will lose is the money spent on retract servo

Juice

Here are the pictures of my setup.

The first four pictures are of the two servos in the center section. Pulling the control rods inwards extends the gear. That's the easy direction. Pushing the control rods outwards retracts the gear. That the hard direction. The servos arms are heavy duty (with three of the four arms trimmed off). The linkages are Du-Bro 2-56 Swivel Ball Links.

The last two pictures are of the bellcranks and retracts. I was mistaken earlier when I said I have 4" wheel... they are 3-1/4" wheels. [] You can see the 4-40 rod inside the wing, bent just right. It attaches to the bellcrank with a 4-40 heavy duty clevis. On the other side of the bellcrank, I can't remember if that is the stock setup. Whatever it is, it's a tight link with practically no slop.

By the way... Notice that I put a fillet of epoxy mixed with microballoons along the edges of the ribs. I actually put a fillet of the stuff on every glue joint that I can reach with a stir stick through the wheel well. I did after reading the early reports of wing failures.

I hope this helps.

Juice

Whistling Death

Well, I maiden my Corsair tomorrow. I got all the systems working except my separate retract battery set up. It will be on the main battery till I get it figured out. My knees will be knocking so bad that I will only be able to fly about 5 minutes.

Wow does the RCV engine ever make this plane heavy. It came in at about 9.5 lbs. I had to put 3.5oz of lead in the tail to get it balanced. I laughed when I saw the estimated flying weight at 7.5-8.5 lbs., I wish!

Juice

Good luck with your flight. Remember to breath. We're all anxious to hear a flight report.

Don't worry about the weight. Mine weighs 9lbs 3oz and the RCV will flies it no problem. This RCV was previously on a TF Corsair that weighed 10.5 lbs. It flew that one well too.

Juice

Whistling Death

Good to hear about the weight. I figure the RCV will pull it just fine, there was plenty of thrust coming from the prop when I was setting the throttle and glow driver to day. I just wonder how it will effect the landing. Does your corsair float in or does it grease in?