Axles
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funseventy
- Posts: 230
- Joined: Fri Oct 25, 2002 11:46 pm
Re: Springs in place of bungees
Atlee has no email or web presence but he does have a fax. The last time I called, his wife answered the phone and when I asked if he had an email address, she said "No but he can come to the phone. Do you want to talk to him?"Trapper wrote:Dos Atlee Dodge have a web site? How much do these springs cost?
Thanks Trapper
Atlee is prejudiced but he will tell you that springs are superior to bungees. He has welded enough Cub gear back together to have an informed opinion. In his shop he has a great series of pictures of Cub returning after an incident that busted the landing gear (not ski ) bungees. The pilot was smart enough to have installed some of Atlee's Cub safety cables and the pilot made a normal landing, probably saving >$20k in rebuild expense.
I personally know one Cub pilot who lost a ski bungee two years ago. He had a safety cable but that failed too and he made a landing with one ski pointing the wrong direction. He was very lucky as he had glare ice and did very limited damage. In snow he would have wrecked . Springs in lieu of bungees are cheap insurance.
Pete Brown
Anchorage, Alaska
N4563C 1953 170B
http://farm3.staticflickr.com/2366/2527 ... 4e43_b.jpg
Anchorage, Alaska
N4563C 1953 170B
http://farm3.staticflickr.com/2366/2527 ... 4e43_b.jpg
Axel Bolts
O.K. Sports fans here is the scoop on the axel bolts.
You have no doubt heard that you should use NAS bolts for your axels. An NAS bolt is a much stronger bolt than a standard AN unit.
The NAS bolts called for in the ski installation paperwork no longer exist. They have been superceeded by a new nomenclature called MS bolts. They will not be found at the local FBO, Aircraft Spruce, Wicks. Wag Aero etc. I found them at " Genuine Aircraft Hardware " 1-888-247-2738. They have a great catalog with a lot of hardware reference data in it. They are also an openly Christian company which is refreshing in this politically correct age. Praise the Lord.
I have a 53 model 170 with the Lady gear so the top holes are smaller than the bottom. The top bolts are 5/16 and the bottom are 3/8.
the top bolts are MS20005-26 (the last two digits are the length in 1/16"s of an inch. I don't have many spacers, you may need a longer or shorter bolt depending on spacers). They are 6.75 each.
The bottom bolts are MS20006-25(the don't have /make -26) you could go longer but you can only take up so much slack with washers, correspondly you should show 1 to 3 threads out of the nut. These puppies are 12 bucks each. this gets expensive fast.
One of the things that makes these bolts so strong is that they don't have a square corner between the head and shank. Sharp corners are stress risers, rounded corners are better. Due to this rounded corner you must use a special beveled washer under the head. So you need MS20002C5 and 20002C6 Counter-Relieved washers. You only need one per bolt but they are sold in packs of 25 at 5 bucks a pack. You need regular washers of the hardened type to match the bolts not a regular AN type so you need MS20002-5 and 20002-6 washers, 25 to a pack at 2 and 4 bucks per pack respectively. Then you need nuts MS21044N5 and MS21044N6 at 25 per pack at 4 and 5 bucks respectively. This will be a little over 100 dollars just for the nuts and bolts to hold those 500 dollar axels on. Are we having fun yet? When I replaced my hollow AL axels I found several AN bolts were bent and one of the axels was bent so maybe we do need all this stuff.... but its gonna cost a bunch, course a ground loop is gonna cost even more. So there is a list of what you need, where to get it and what its gonna cost. OHHH SANTA.....I've got a few wish list changes...
Happy Holidays Ya'll
Bill
You have no doubt heard that you should use NAS bolts for your axels. An NAS bolt is a much stronger bolt than a standard AN unit.
The NAS bolts called for in the ski installation paperwork no longer exist. They have been superceeded by a new nomenclature called MS bolts. They will not be found at the local FBO, Aircraft Spruce, Wicks. Wag Aero etc. I found them at " Genuine Aircraft Hardware " 1-888-247-2738. They have a great catalog with a lot of hardware reference data in it. They are also an openly Christian company which is refreshing in this politically correct age. Praise the Lord.
I have a 53 model 170 with the Lady gear so the top holes are smaller than the bottom. The top bolts are 5/16 and the bottom are 3/8.
the top bolts are MS20005-26 (the last two digits are the length in 1/16"s of an inch. I don't have many spacers, you may need a longer or shorter bolt depending on spacers). They are 6.75 each.
The bottom bolts are MS20006-25(the don't have /make -26) you could go longer but you can only take up so much slack with washers, correspondly you should show 1 to 3 threads out of the nut. These puppies are 12 bucks each. this gets expensive fast.
One of the things that makes these bolts so strong is that they don't have a square corner between the head and shank. Sharp corners are stress risers, rounded corners are better. Due to this rounded corner you must use a special beveled washer under the head. So you need MS20002C5 and 20002C6 Counter-Relieved washers. You only need one per bolt but they are sold in packs of 25 at 5 bucks a pack. You need regular washers of the hardened type to match the bolts not a regular AN type so you need MS20002-5 and 20002-6 washers, 25 to a pack at 2 and 4 bucks per pack respectively. Then you need nuts MS21044N5 and MS21044N6 at 25 per pack at 4 and 5 bucks respectively. This will be a little over 100 dollars just for the nuts and bolts to hold those 500 dollar axels on. Are we having fun yet? When I replaced my hollow AL axels I found several AN bolts were bent and one of the axels was bent so maybe we do need all this stuff.... but its gonna cost a bunch, course a ground loop is gonna cost even more. So there is a list of what you need, where to get it and what its gonna cost. OHHH SANTA.....I've got a few wish list changes...
Happy Holidays Ya'll
Bill
Thanks, Bill, for the good info. This is the sort of message postings that are truly helpful.
They charge $6 for their catalog, and I'm sure it's worth it, but they have a free website, http://www.gen-aircraft-hardware.com/
This hardware-differences issue is notable. Example: The correct bolts to attach the vertical stabilizer are NAS bolts. (Superceded to MS is fine.) For the reasons you just mentioned, those bolts are superior to ordinary AN bolts, and the vertical stabilizer is a critical component on all aircraft. (Just ask American Airlines.) I've seen several aircraft with common AN bolts in that location, including one that is presently for sale. Only a knowledgeable person would likely catch this error and is another reason to get prospective airplanes properly inspected before purchase. (Those NAS bolts are usually $80 - $100 each, but a loss of control is priceless.)
They charge $6 for their catalog, and I'm sure it's worth it, but they have a free website, http://www.gen-aircraft-hardware.com/
This hardware-differences issue is notable. Example: The correct bolts to attach the vertical stabilizer are NAS bolts. (Superceded to MS is fine.) For the reasons you just mentioned, those bolts are superior to ordinary AN bolts, and the vertical stabilizer is a critical component on all aircraft. (Just ask American Airlines.) I've seen several aircraft with common AN bolts in that location, including one that is presently for sale. Only a knowledgeable person would likely catch this error and is another reason to get prospective airplanes properly inspected before purchase. (Those NAS bolts are usually $80 - $100 each, but a loss of control is priceless.)