Originally posted by SimonNicholson
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Lifting completed Bearhawk to change undercarriage bolts
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Originally posted by Oriwha View PostHi Battson, all you need is to come visit my build and we will do the change while you are here. Lifting device is a 12 ton digger, using 5 ton strop on engine mount. Real easy.
Dave Devine.
I can't wait to see the decisions you have made and how you've fitted out the plane, always fascinating to see another way of finishing out the Bearhawk kit.
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Think this will work? I’m planning on testing with the tractor and something heavy tomorrow. Maybe someone make some calculations and give me an opinion. .090” 4130. Forged eye bolt 3/8. The nut will be welded to the new bracket.
The plan is to have some kind of cap in the skylight or trim piece when the eye bolt is not in use.You do not have permission to view this gallery.
This gallery has 1 photos.Last edited by Mruffatto; 11-05-2021, 10:44 PM.
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FWIW, this is what Rob Taylor came up with. They stay on the aircraft. He attaches the lifting bar to the lift fittings using shackles.
float lift fitting 2.jpgside view float lift fitting.jpgfloat lift fitting 1.jpgfloat lift fitting 4.jpg
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Originally posted by zkelley2 View PostAtlee dodge makes a set that work perfect. You can just buy them. They've been on my plane since the beginning and were used extensively this year messing with the floats.
No welds to break and they're stainless.
N678C
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I talked to Bob this morning about these. I asked if they could be made like the wing tiedowns and he said they could. 1/4" 4130 rod is adequate, he said you would have to really screw up the welds to have a problem. Use .062 plate with at least 1/4" edge clearance around the bolt. Might be something for the factory to consider making for those who don't weld.
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Originally posted by Utah-Jay View Post
Photos if possible?
Originally posted by SimonNicholson View PostAs you know Jono, I am fitting my Bearhawk out for floats. I am making some lifting eyes out of s/steel like they use on the cubs and have them permanently fitted to the spar bolts.
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Wouldnt it work to install a 1/8 inch flat strip with an eye in it--- welded to the fuselage tubing uo between the wing root and the skylight-----one on each side and lift the whole plane near its cg--- lift from the roof with a chain hoist..... a couple of 1/8 inch fins about 2 inches by 2 inches wouldnt be much drag-----
be mighty handy for litfing in the shop........
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Originally posted by jaredyates View PostIf you don't want to lift at the wing, how do you feel about resting on the wing? Could you jack it up, install a prop under the wing, then lower it back down?
The bolts were all in good condition considering their age. They all had some minor corrosion, some worse than others, but then again I didn't apply enough grease when they were installed. They have provided 10 years / 1000 hours of service and seen a lot of rough off-airport landings, beaches (salt), been in the water, and been outside for collective months over that time. The engineer stated they would have been good for another 10 to 20 years of service. Although we did not use any dye penetrant to look for cracks.
We ended up lifting the plane using jacks under the wing spars, which has been suggested before. We used professionally made and purpose-built wing jacks, under professional supervision, which worked pretty well - there are a few notes for those considering this option:
We found the whole plane needed to be lifted in the level flight attitude, roughly. Although we left one wheel just slightly in contact with the ground to manage our risks.
The plane did try and tip forward onto the nose, very slowly - it was hard to perceive... We did notice it, thankfully, and attached a 'pig' to the tailwheel and tensioned that against the jack. I think this problem could occur if lifting a nose-heavy Bearhawk by the wing spar, if the plane approached level flight attitude. Something to be aware of.
The padded plates were large and included steel angles underneath for strength, the padding was thick and suitable. It still left the littlest almost imperceivably small mark where the spar is, it's not even a crease, just a very slight 'adjustment' - if you are the builder you might notice it, nobody else will. Clearly this isn't the ideal outcome or specifically desirable, but it is so very slight, it won't be of any concern - structurally or aesthetically.
IMG_20220702_143730.jpg
Sorry about the photo, the lighting was not good all afternoon.
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I made a “U” shaped fitting with a drilled 7/16” hole and nut tacked in the middle to fit to the front spar attach assembly. .125 4130. The part that is horizontal is shaped with the slant of the roof and is slightly below the root fairing. I placed two small access covers in the fairings which allow a lifting bar to be threaded to the fittings. These are the only pics I have on my phone that come close to showing what’s thereYou do not have permission to view this gallery.
This gallery has 3 photos.
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To put a BH on floats the entire aircraft needs to be suspended from the lift points and it is way up in the air…it’s a scary sight! Interestingly enough the aircraft doesn’t weigh the same laterally. I didn’t realize this but Rob did. He had some weights, a plastic bucket and rope ready. He balanced the light side out by tying the bucket to the wing tie down and adding weight until it was level side to side.
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