Anyone have any experience with these installed retracts? One of our members finished up his plane and tried to taxi on our grass field. Just as he made his first turn, one wheel folded up.
There isn't much info on setting these up. Any tips? Or are the mechanical retracts not much good?
If they are like the Hobbico ARF version, and I suspect they are, the frame metal is soft, and the tolerances are wide. Better to save yourself some grief, and get a good set like Robarts. Dr.1 Driver "There's a Hun in the sun!"
There was a review of that ARF in RC Report a couple of months back. The main problem with it were the retracts.
John VB
The retracts seem to the weak point on an otherwise fine plane. There are several threads on RC Universe the deal with the H-9 Texan and fixes to improve the retracts. Go to the ARF section of the Airplane forum and do a search on TEXAN. Look for the threads that specify H-9 Texan. Some of these are several pages long, but contain a lot of good information.
The two issues that causes the problem with the retracts is the 5/32 wire strut and the fact that retract only extends 85 degrees rather than 90 degrees. The 85 degree extension makes the plane look as if it is pigeon-toed or bow-legged and puts a lot of side load on the gear during taxi, take-off, or landing causing the wire strut to flex excessively or bend. The gear mechanics seem strong enough to handle the loads.
The simple fix is to put in a stronger (3/16) strut. The good news is that Robart Mfg. (630) 584-7616, makes a strut that is a perfect fit. You just need to remove the existing strut and drill out to fit the Robart struts. P/N's for these struts are 618-010M (RH) & 618-001M (LH). These are used on the retracts that they make for the Top Flight AT-6. Price is $8 each plus shipping. The struts are a little on the fat side of 3/16. I wound up using a #10 (.1935) drill for a proper fit. You also need to drill the wheel hubs and cut the wheel well out a bit to clear the spring coil. I drilled out the existing wheel collars and re-used them. These are a little thinner that the DuBro's and fit better.
I also modified the retracts to extend to 90 degrees, which is probably not necessary, but make the plane look a lot better when it's sitting on the ground. One of the threads gives the method of doing this mod. It's not hard to do, but does require using very small (0-80) screws and taps, which you may have to order. If you need any more information about this, let me know.
I flew my AT-6 (or is that SNJ, because of the navy marking) for the first time yesterday using a Saito 100 for power with a Master Air Series-K 15-6. Wonderful engine! Never had an engine run as well will so little time on it. Run in per instructions, 20 minutes on the bench at less than 4000 rpm. The stuff coming out was that same color as the stuff going in. Set the high end to about 9000, set the low end to idle about 2400, put it in the plane. Takea off about 3/4 power, cruises nice at about 5/8 power. Four 8 minute flights used less than a quarter gallon of fuel. Love the sound of that engine.
Actually the retract mechanics aren't too bad. Glass filled nylon and are plenty strong. It's the strut that causes most of the problem.
Typo on the LH gear P/N should be: 618-011M
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