Okay, I've searched the board and have read everybody's opinions on using 615s on the TF Gold Corsair.

Seems to be a great number of people who have had problems with these, even though they're the recommended hookup by TF. As for CJs, a great many just don't care for them either. I see that as far as weight, most people are weighing in around 10lbs, which is the max. rating for these retracts - (might explain the problems). I'm not looking forward to completing the build only to find these things fold up on my first landing.

So the question is, does anyone have a recommended solution on what to use?

Good luck. You would think somebody else out there would make a good set of rotating retracts for up to 15 lbs, but I havent seen it yet. Buy lots of extra parts (especially the little scissor arms) I dont think Ive ever flown more than 4 flights on my GSP corsair without bending one. But at 12+ lbs Im probbly pushing those 615's a little farther than they are designed to go

I had the Robart 615's in my corsair and they were a bit of a problem for a while.. Robart improved them and I bought the upgraded parts.. That helped.. The biggest problem I had was the wheel turning upon landing.. they changed the gear at the top of the strut and went to using 2 set screws to secure the leg..
If your scissors are bending.. why not just make a set out of aluminum and be happy?.. lol Regards BobH.

Biggest problem I've had with the Robarts is the 'scissors', or links as Robart refers to them as. These are easily bent out of proper shape by a slightly hard landing, and I don't consider them to be repairable. Best to stock up on spares, as another has suggested. I have the CJs also, and despite the problems with the Robarts, I prefer them (Robarts).
Robart could cure the problems by making thse links stronger, either thicker metal or stronger metal, maybe sprnig steel, but they turn a deaf ear to our complaints and gladly sell us spare parts.
My (Top Flite) Corsairs weigh under 9 lbs, with retracts and flaps, so don't etch that 10lb figure in granite.
See my gallery for pics of my Corsairs

Hang in there guys I'm trying to get B&D retracts to look at a mod that I did on their retracts. And so far nobody has been able to make them not rotate or retract properly. Next is to put them on my corsair and see what will happen. Mine is a TF giant scale powered with a US41 so we will see what the summer will bring. Hopefully I will have it done for the labor day fun fly at Taylor Mo. Then I will see what other modelers say about them.

The gentleman from KMP had a set of .60 size rotating retracts at the Toledo show this year. These retracts are designed along the Spring Air design which uses a one way air valve to retract the gear and a spring to deploy, piece of mind you won't be doing belly landings. The gear housing was an aluminum billet so you can bet the wing is coming apart before the retracts are giving in. The gentleman was not aware of the problems everyone was having with the Robart 615's. He implied he had a ready supply available. Try contacting him through his web site www.kmp.ca and see if he can't help.

I have the Robart 615's in my TF Corsair and they are nothing but problems. The slightest bind in the mounting rails and the gear will not cycle and anything other than perfect touch downs will bend the hinges, mine bent on the second landing and had to be replaced. This past weekend the gear decided it wasn't going to deploy all the way. We tried everything including deploying the gear at the bottom of a loop but they were not coming all the way down into the locked position. Finally had to belly land damaging the cowl and breaking a $15 APC prop. Robart should be absolutely embarrassed to sell this gear. These planes require a lot of money, time, and effort to build only to be lost to a poor design execution of the landing gear. TF should also be concerned, they can't be selling as many Corsair kits as they could with a decent retract system available.

Dan, that link doesn't work ?? Took me to a dutch printer place lol.. BobH.

Sorry, there is no "n" at the end, it is www.kmp.ca. Edited my post to reflect the correct address.

Thanks I got there.. BobH.

I too saw (and fondled) the KMP retracts at the Toledo show, and they DO look very promising. Struts appear to be 3/16", which is just right for these warbirds. I inquired as to whether they are available seperately (from the Corsair ARF that they sell), and was informed that they are not at this time. When/ if they do become available, then Robart and CJ will have some SERIOUS competition, and we may have a winner in rotating retracts.
Yes, Robart should be ashamed, but so should CJ. One thing about the Robarts that I consider a plus: they actually have 100 deg. of retraction, which allows the installer to mount with some forward 'rake', which in turn allows the RoboStruts (if so equipped) to function better. They also are easier to fit/ install into the wing than the CJs, and have a lower overall profile. And then there are those CJ struts, they are just plain ugly and cheap looking, especially compared to RoboStruts. The CJs just may hold up better to hard landings, but all factors considered, I still favor the Robarts over CJ.
The old (discontinued) Rhom-Air retracts are a good alternative to Robart and CJ. Simular in design to the KMPs, and available with 3/16" struts. I have had good success with the Hobbico mechanical rotating retracts, BUT I use them in a 5 1/2 lb DynaFlight FunScale Corsair, and would not consider using them in anything heavier.
One more thing about the Robarts: many have encountered problems with the struts rotating when they are not supposed to (including myself). I consider this to be a builder issue (as in MY fault), as it is usually due to insufficient number of set screws and/ or failing to grind small flat spots for them to anchor onto and/ or not tightened enough. I now install 4 , 6x32 set screws into each RoobStrut, and enlarge the gear tooth set screws to 6 x 32, and use button head or regular allen head screws when possible (easier to apply more torque on button head and allen head than regular set screws). With that done, my unwanted rotating problems went away.

Check this site out for mechanical retracts for the .40 size Corsairs (I think they are on page 7, won't show a picture). Wing Manufacturing had a set at their booth in Toledo and were kind enough to send the info to me. They looked great in their (Wing Mfg) .40 Corsair and could even be fitted to the GP Corsair (ugh! flat sided fuselage). Much sturdier than the Hobbico set and are only $25.00.

PS: The owner of KMP told me he would sell me the .60 size retracts and even quoted a price. He told me he was ordering a new batch from overseas. Since it looked like retrofit would be quite a bit of work I did not purchase them but plan to build a new plane and incorporate these retracts.

DanB
How much did he quote you for the KMP retracts? Where they 100deg?
Edwin

Bob
I don't remember the exact amount but it was a lot less than I paid for the Robarts. Pricing may change once he gets a feel for what the demand might be, but he impressed me as a smart business man who would price for a fair margin and not gouge his customers. Compare his P-38 ARF pricing versus Morris Hobbies, about half the price and much higher quality. I was not smart enough to ask about the degrees of rotation, but they were made for his Corsair.

Hey, that one in the Wing Mfg. booth was MINE! And so are the retracts. Really, the new owner (of Wing Mfg.) is a member of my club: the ThunderBirds R/C Club, and Dan asked me to build one of his Corsair kits so he could display it at Toledo. I was not able to complete it in time (I recieved the kit in late Feb.), but he chose to display it anyway. The retracts are the same ones used in some 40 size ARFs, and cost $25 a set. The design looks good: simple but effective, but with only 5/32" stuts they would not be robust enough for 1/8 scale Corsairs. Thus, there were some discussions with B&D (next to the Wing booth) to see if he could come out with a heavier duty version. Here is link to those retracts:
http://www.ecsvr.com/abm/shopdisplayproducts.asp?page=7
I still haven't completed the Corsair yet, and construction is slowing down now that warmer weather is finally here, but I intend to have it flying at our club's WarBird Day, Sat June 28th. The Corsair BTW, shows what can be done with a foam wing: it has 1/16" strips on outer panels to duplicate fabric covered wing ribs as in the full scale.

You know, this is crazy . . .

From what I gather, people just aren't happy with the 615s and if I understand right several people have contacted Robart expressing the same. I've sent them an e-mail this morning asking if they've corrected the issue and have referred them to rcuniverse if there's any doubt.

I'm just not looking forward to building this plane to only have it wrecked on a landing. Nor do I want a hangar queen . . .

Consequently, I take it there's no other solution except for installing non-scale gear that's more reliable. Any further suggestions? How about gear made for heavier aircraft?

AK: I'm not sure what you mean by "non-scale gear that's more reliable". I'm guessing that you are refering to the struts. If so, I think most will agree that as far as Robart's RoboStruts, we have no issues. They are great looking and functional (altho rather pricey). They can be installed on other makes of landing gear. I even installed them on CJs, but with a lot of enginneering. Those who saw the Corsair at the Wing Mfg. booth (at Toledo) may have noticed that RoboStruts were installed on the $25 mechanical retracts on that aircraft. If the KMPs become available (for sale), the ideal setup could become those retracts with RoboStruts installed on them. The main thing to remeber when using RoboStruts: don't be skimpy with the set screws, and be sure to file flat spots, but not too deep. The flat spots need to be just deep enough to provide a small area for the set screws to grab. File too much away and you weaken the wire strut.
And about contacting Robart to express my dissatisfaction with the 615s: I have done so, by e-mail, and in person (at Toledo). I know of other people that have done the same. I have also talked to CJ about their retracts, and both groups do not seem at all interested in our complaints, and/ or making an attempt to resolve the issues by making product improvements. This should be a very clear challenge to anybody who'll listen: WE WANT GOOD ROTATING RETRACTS, and you are not providing them.
I would like to give the KMPs a try.

Humm...

I wonder if the retracts which I purchased for my Wing MFG. Hellcat are Robart 615's? The kit is a 60 size warbird and these retracts fit the diagrams/plans to the letter. They rotate and fold 'back' into the wing (similar to or the same as the F4U to the best of my knowledge.)

I picked them up brand new out of package at a swap meet so I don't know the model #. The complete set (struts, wheels, tank, pump, valves, etc.) was $50.00 - so I couldn't pass it up. Seems now that maybe I should have.

Is there any way to tell the model # of the retracts? What do new the replacement parts cost?

Thanks for any info you can provide,
TRP

Thanks for the input . . .

What I was leaning for in the "non-scale" comment, ableit not coming across in the best manner, was that maybe it'd be just best to forget the 100 degree rotation and just install some reliable retracts.

Maybe it's the pilot side in me coming out. It's kinda difficult to takeoff, knowing there's a definite design problem with the gear, and that I've got a better than even chance of the gear folding on touch down.

A flyin bud of mine removed the retracts on his TF corsair and installed fixed gear. Just got fed up with it. Dont look quite right in the air, but he's been flyin it for a long while. As for puting in heavier corsair retracts, dont think there is the space for it. Will have to go to 1/5 sized corsairs to get better retracts. But then I wont be able to fly at our field. Too tight for giant scale war birds.
Edwin

TRP: The Robarts are unique in that they are the only ones that have a gear (or 1/4 gear?)which rotates the struts. This gear is mounted at the top of the struts, held on by set screws, and meshes against holes in the landing gear housings. Other manufactureres use different methods to cause the rotation. If yours has the gears, AND has 3/16" daimeter strut wires, then you have the 615s. If you got a complete set for $50, then you got a bargain. Despite my criticsms, they do work well IF you able to make consistent gentle landings. It is also a great help if the aircraft is kept as light as possible. As mentioned, my Top Flite Corsairs typically weigh less than 9 lbs. But there are a great many builders who end up with them weighing in at over 11 lbs.
And as for having them bind up as some have said, that is another builder issue: the mounting rails need to be parrallel. If not, the will case the housing to become warped, and thus cause binding. Regardless of which gear you use, set screws should be plentiful AND tight.
The parts that usually need replacement, "Links" as Robart refers to them, sell for about $6.50 each. There are 4 in a 2 gear set, so a bad landing can cost $26.
615s are the recommended retracts for the Wing Mfg. Hellcat.

Thanks for the info.

Those are the ones I have.

We fly from a 600 plus ft paved runway so any bumps in the landing will be from my shoddy pilot skills, not from the gophers. So if I have to buy new gear links.. then it's my onus.

When you say that the rails need to be parallel - do you mean that the rails must not be twisted from left to right or front to back, and that they rest on the same level plane as each other - per side. (how is that for a confusing definition of ' parallel '?)

I guess I see what you mean because the housing is pretty thin. My first thought is that this can be tricky for the Wing Kit as it uses a foam wing where you need to route out the foam and insert the plywood supports and rails for the retracts. I guess I will need to be very careful in this part of the construction.

I have been putting off building this bird because I had such a bugger of a time building the Wing At-6 with mechanical retracts. That thing came out as the heaviest pig in my hangar. We likened it to a Christmas Ham.

Bleh- Starting to think that maybe I should sell the whole lot and just focus on my TF Spitfire MK IX.

TRP

.

I'm building my TF Corsair 60 with the CJ's I got a great deal and could not pass it up. I had done alot of researched have a thread running on this http://www.rcuniverse.com/showthread...hreadid=450970

None of the other gear manufactures (Spring Air or Sierra) are willing or planning to fill this void.

The CJ's look stout enough but as mentioned they are not as good looking as the Robarts. The CJ's are also a VERY tight fit. Mine are mounted as far forward as humanly possible to prevent nose over and have a good scale location on the ground. I may not be able to have gear doors because without the 100deg rotation they don't recess as well as the Robart's. I'm using the Robart variable valve to slow down the movement and IMHO that's a must.

Finally, as mentioned I agree that the final weight of the plane will ultimately determine how the gear will hold up. Lighter is better. However I'm still planning on putting an RCS140 up front

Any news on a better retract or upgrades that can retrofit are welcomed. Petee

Guys, PLEASE check this post out concerning the topic at hand.

http://www.rcuniverse.com/showthread...108&forumid=34]

BigProp,
The link posted isn't working. Pete

Thanks for the Heads up Pete. I recopied the link address so it should work now. If noy, the title to the post is

ATTENTION: All Top Flite Corsair, P-40, ROBART 615 & CJM Retract Owners !PLEASE READ!

under the Warbirds and Warplanes forum.