Repairable McCutchen Hub Bar?????

About a week ago I damaged my 5' McCutchen hub bar by applying a download to a blade that had been only partially inserted into the bar. Should have asked someone to help with blade removal but didn't!! In any case, the force splt the bar along the leading and trailing edges. About 6" along the leading edge and about 3" along the trailing edge. The blade inserts into the bar about 12" when fully assembled. So, does anyone think that this is a repairable bar? I have attached two photos showing the LE and TE cracks. My hand is applying pressure to make the cracked area clearly visible in the photos.

Second question. My understanding is that McCutchen blades and hub bar are drilled as a set. Thus a replacement (used) hub bar would probably not mate with the existing blades. Is this the case?

Thanks for any comments

John vK

I don't know about repairing that hub bar, but I know you can over come the holes not lining up with the blades.

I got a longer set of McCutchen blades for my gyro, had a 23 footer and went to 25.

The two new blades did not match up with the original hub bar, But it was close. We drilled out the Hub bar to center up with the bolt holes in the blades, then using the center of the new holes in the hub bar, we enlarged the holes but did not go all the through, only made a recessed hole.
Then on the hub bar we epoxied some bushings into the fiberglass, centered to match the holes in the blades.

Worked out great and did my first runway flights with the new blades yesterday. Will do the pattern tomorrow. and then load it all up for ROC.

When I take the blades down I will photo it if you like but here is a quick drawing of what we did.

Hi Phil,

What software did you use for that sketch?

Jim

i'M NO EXPERT ON ANYTHING...but the cracks in the blades look like cracks in fierglass to me .... whats wrong with grinding down the crack and fiberglassing the thing ? you know good old fashoned repair work ????
what looks like what happened to me is the weight of the blade split the end of the blade where the hub bar incerts into the blade ... it thats all and it were mine I'ed repair it with regular fiberglass... I would probly ADD a few more wraps of class arround the ends so that same thing doesn't happen again , and do it to both blades and do a complete re ballanceing of the blades after the fact... ballance the individual blades at the same point on each blade then when on the hubbar apply weight at the same point that you ballanced them individually on ...( usually a few coats of paint will do it ) if its alot of weight needed just be sure you add the weight at the line you ballanced the individual blades on ... its very important that each blade weigh the same at the same place or it will shake !

Just my 2 coppers

repair it and make it stronger !

c ya !

Bob......

I don't think your hub is that bad at all. Not that I know anything but I would use west system epoxy with no fillers wet the cracks clamp it tight and 24 hours later go fly. Cracks that run the cord of the hub would be trash. If you trash that one let me know I want it.

Do what Brent said.

The hub bar will be clamped together by the bolts when it is assembled.

Jim, I used Adobe Illustrator 10. It's a rough sketch but I think it gets the point across.

Good job Phil, I'll have you draw the tech drawings of the GS force landing gear, and my nose wheel!

I'm all over it Buddy!!!!!!!

Thanks Phil,

Jim