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Bracket and Toe

Capflyer

Well Known Member
Friend
Wondering if there is something off the shelf or what others have done/fabricated for an inner wheel pant bracket that could fit the setup on my HRII. I have Matco WHLBE9 dual piston 4 pad calipers which are about twice the size of the typical calipers used on RV's and the Van's inner bracket will not fit. I'm also curious if anyone knows what the maximum toe out alignment would be acceptable. Not having all the weight on the wheels yet (wings are not on yet), the current toe out is about 5 degrees. I know that will decrease some when all the weight is on.
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I can speak to alignment since I’ve recently been through every aspect of it.
I hope your sockets are not yet drilled…
-Wait til the wings and tail are on
-Load it up to 1600 lbs
-use Vince Fraizier’s alignment brackets and align to zero toe in/out in the 3 point attitude.
-strongly consider shortening the gear first.
Do you have the F1 mount and gear? It’s a lot of coin but is well worth doing on a yet to fly aircraft.
 
Thank you for the response. I have the HRII engine mount and gear legs and way too far into the build to switch them to the F1 versions. The gear legs, sockets on the engine mount, the wheel mounts and lower gear leg were already drilled and there is no way to shorten the legs because of their shape. I definitely do not want any toe in but that should not be an issue. If I need to adjust the toe out closer to "0" I'll need to fabricate some shims. I would imagine some toe out is acceptable, just not sure how much would max that out.
 
I have experimented with small amounts of toe in and toe out on my RV-8, since it is really easy to shim the axles.
I can tell you that even 1/3 degree of toe-out makes the airplane very nasty. 1/3 degree of toe-in is not noticeably different than zero. But strive for zero. I've posted before why toe-out is bad with engineering force diagrams. The myth seems to perpetuate that toe-out is not bad. This is why I did the direct test of switching my shims. Wow what a difference. You can turn a very docile taildragger into an SOB really easily with just a little toe-out.
 
That’s great info, Mr. Smith
If you use Vince’s method of checking in 3 point attitude at 1600 lbs and shim to zero you will be happy with handling and very happy with tire ware.
Good luck!!
 
Much has been said on this subject. I agree with Vince and I believe John Harmon told me the same thing when I was finishing my Rocket. 0 toe and 0 camber. My original RV4 I set up with zero toe in a 3 point attitude. (we drilled the gear legs back then) and It tracked beautifully and had even tire wear. I shot for the same with my rocket with good results. I just finished realigning a buddys Harmon rocket for zero zero who was having heavy shimmy problems. He had excessive toe in and alot of positive camber. I just kicked it out of the hangar today so the Jury is out on that one. John Harmon sells shims for our set up that are a real help.

I had to do some deep digging to find it but a fellow by the name of Chad Jenson on here had emailed me a template for mounting my Sam James wheel pants. This was back in 2011 so I was surprised to find the email with the PDF. If you want to send me your email l can forward that to you. They worked for me but I am not sure about your brake install. You might be able to modify some.
Best of luck with your project, nothing is ever the same after a rocket!
Ryan
 
Ryan, excellent info on the alignment...thank you. PM'ing you my email address. I didn't know Harmon had shims, I'll shoot them an email for them along with some other optional stuff they have.
 
Ryan, excellent info on the alignment...thank you. PM'ing you my email address. I didn't know Harmon had shims, I'll shoot them an email for them along with some other optional stuff they have.
I sent that PDF yesterday. Did you get it?
 
Ryan, excellent info on the alignment...thank you. PM'ing you my email address. I didn't know Harmon had shims, I'll shoot them an email for them along with some other optional stuff they have.
Assuming you're talking about the wedge shims that go between the axle and the gear leg socket, one shim is OK, but adding more shims will cause the axle bolts to necessarily bend in circles as you tighten them. Ugh.

I don't know what the absolute limit is for adding shims, but I'd guess that 5 degrees of correction might be a bit much.

Cut and re-weld the gear leg socket plate if needed to correct the alignment. It's not that hard to do. Read about it http://vincesrocket.com/Additions after 10-27-04.htmhttp://vincesrocket.com/Additions after 10-27-04.htm
 
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