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Steve Pierce
11-04-2008, 06:35 PM
Cathy has been flying a friends Tri-Pacer and I noticed the bungees have been sagging a bit. A little investigation reviled 2 1080s were installed last time and it has always been my experience that that combination normally only last a year or so before the sag sets in. I ordered two 1280HD bungees and thought I would swap out the one 1080 since they were pretty new. Cathy removed the seats, put the tail stand on the tail guard, weighted the left wing at the tie down fitting and picked the front of the airplane up at the propeller via a prop sling and engine hoist until the right wheel cleared the ground.
1108
She then removed the top bolt out of the right hydrasorb, picked the right gear up enough to stick a milk crate under it and expose the bottom hydrasorb bolt, removed it, and wiggled the hyrdasorb out the top.
1107
I then cut one of the 1080s off and installed a 1280HD and she reversed the process to install. It was time for soccer practice so we will finish up tomorrow.
1109
1106 (http://www.shortwingpipers.org/forum/attachment.php?attachmentid=1106&d=1278953598)
You can see the 1080 and 1280HD bungee installed closest in the picture and two 1080s on the far side. We will see how this works out because my Pacer and Brian's Tri-Pacer all have fairly new 1080s with a sag. :cry:

Larry Huntley
11-04-2008, 08:05 PM
That is how it works on my Tripacer except I put a barrel under the tailskid. I was wondering why some were pulling the hydrosorb out the bottom. Larry

Frank Green
11-05-2008, 06:38 AM
I pick mine up by the motormount at the fire wall. After taking out the hydros I put in a short length of chain so I can set her down while I take the hydros home to change. I use 2 1080HDs on a standard Tri and no problems. If you are using regular 1080s they are rated at 750lbs. each(1500). 1080HD are 900 lbs(1800). Your combination of one 1080 (750) and one 1280HD (950) yields a combo of 1700 lbs. 2 1080HDs are 1800 lbs. The difference is the 1080HDs are 5/8 diam. vs the 1280HD at 3/4 and the double 1080HDs fit on the Hydro and in the plane a little better.

JohnW
11-05-2008, 10:59 AM
That is how it works on my Tripacer except I put a barrel under the tailskid. I was wondering why some were pulling the hydrosorb out the bottom. Larry

Because...it's incredibly easier! You don't even have to remove the seats to change the bungee cords (and only unsnap ONE SIDE of the leatherette cover), and since you HAVE TO crawl underneath to remove the lower bolt on each HydroSorb anyway... what could POSSIBLY make more sense than "while you are RIGHT THERE" to put your foot on the lower half of the tire on that side, push the gearleg out/up "just enough" and TAKE THE SHOCK OUT, all in one motion? No messin' around with slippy-slidey on trash bags or grease plates, no leaning inside trying not to shake the airplane, no callisthenics to "wiggle the shock out" and by golly getting the top bolt in is "pleasantly possible" without messin' around with a comealong. Lookit...TRY it, you'll like it. Airplanes were MEANT to be "off the ground". You could STILL "chain binder" the gear and even set it back down on it's sneakers overnight, if it blows up yer skirt. Been there, done that (but I use an "old set" of HydroSorbs with 50 year old bungees on it).

I represent the remark: "Give an unreasonable task to a Lazy Man, and he'll find the easiest way." I suppose if you WANTED to do it the hardest way possible, you could find a way to take the bottom bolt out by working past the battery box from the "top"!!! You could always die grind the "superstructure" (or "birdcage", or "Piper channel") off enough to push out the bolt and weld a new piece back in when you are done...

Steve Pierce
11-05-2008, 11:20 AM
John, Isn't it kinda a pain to get the bolt out with the seat in? Took me a few minutes to pop the seats out and Cathy did the rest except for actually installing the bungee. She did it in the time it took me to spray a cross coat of dope on an aileron. What is the reference to "slippy-slidey on trash bags or grease plates" and "comealong"? I remember pulling it out through the bottom and pushing the wheel out with my leg, kinda heavy and cumbersome, this was way easier for me. ;)

Curly
11-05-2008, 03:21 PM
Steve - A wife who can change the bungees on a Tripacer!!!! - You surely are blessed - make sure you treat her right as she is definately a keeper.

Curly

smcnutt
11-05-2008, 03:46 PM
Steve - A wife who can change the bungees on a Tripacer!!!! - You surely are blessed - make sure you treat her right as she is definately a keeper.

Curly
...and she's a pilot http://www.shortwingpipers.org/phpbb3/viewtopic.php?f=5&t=515&p=4380#p4380 Now if you tell us she can cook, you might have a stampede heading to your doorstep! :lol:

JohnW
11-05-2008, 03:59 PM
llSteve; well, that's kinda my point...the garbage bags and/or grease plates have something to do with "letting the gear swing out to get the bottom bolts"...or sumpthin' (?) when you winch the gear TOGETHER (which is -again- my point!). YOU apparently are (not "apparently", you ARE!) talking about lifting the airplane up off the wheels. So am I! When you raise the aircraft off the wheels, GRAVITY keeps the gear together and the only reason I would refer to a comealong otherwise would be to LIFT THE AIRPLANE (and I think I have related my preferences about THAT enough times on the past. But then, my Posts are sometimes AWFULLY LONG and maybe some people don't read "all of them, all the time". Short attention span, I'd think ;) ).

What I have been taking exception with all this time is the "you don't have to pick the airplane up at all if you are winching the gear together" way of doing this task. Maybe...just MAYBE!...I misunderstand something about "another way to do it", but to ME, raising the airplane up off it's gear is the ONLY way to fly (pun intended!).

No, I have no problem removing the top bolt(s) with the seats in. I remove the nut, install a fine thread "hardware store" nut on only about 3/4 the thickness of the nut, put a 1/4" drift punch in the open part of the nut (so it bears on the end of the bolt and doesn't jump off sideways) and tap it forward with my handy-dandy rebar shanked, brass headed home made does everything hammer (I don't own any "Store bought" hammers except bodyman's hammers and a wee tiny ballpein and a 6 pound sledge ( for taking out stabilizer cross tubes. just kidding). Then there's an Estwing 20 oz claw hammer and it's framing cousin but they are only for wood, like building things like sheds and doing home renovations and the like). Once you get these bolts to move, I put a socket on the bolt (with a small breaker bar, not a ratchet) and slide a 7/16 wrench over the shank. Rotate the head back and forth and push on the underside of the head with the wrench and out she comes. I've had to use vice grips (and some awful dirty names, sometimes) but if they come that hard, they'll be needing new bolts anyway. But then I'm also of the "use new hardware" school of thought anyway.

For putting them back, I'm a big fan of "home made alignment studs" (long bolts with the heads cut off and put in the lathe and turned down a few thousandths -and of course, a taper ground on the end. A small hole in the "handle end" and a piece of forty thou' safetie wire makes recovery a snap when the "real" bolt chases it out of the holes. If I HAVE TO take out a seat or two, I certainly would...but normally if the airplane got new bungees every few years like they SHOULD, they aren't usually a problem.

Glen Geller
11-06-2008, 12:01 PM
I have replaced bungees on four or five PA22's, we also lift with an engine hoist from the motormount at the firewall, it requires removing the upper cowl (just four fasteners) but avoids possible damage to the prop/spinner/crankshaft/crankcase/motormounting hardware. My mechanic has done it via the motormount at the firewall method thousands of times since he was a young man in WWII.

Steve Pierce
11-06-2008, 12:39 PM
John, I must have missed that thread. I always pick it up. Easier to line up holes. Another note: Sometime the hydrasorb gets tweaked a bit and the holes won't line up. I try and install the hydrasorb in the same exact position as it came out. Sometimes if it is 180 degrees out it is hard to line up. The bullet alignment pins John mentioned are also a major help.

If you have a spreader bar the prop sling works nice because you don't have to remove cowling and fish a strap around all that stuff at the firewall. The prop holds the engine up in flight and have not heard of any problems doing it this way. Done it both ways for years with no problem either way but sometimes it isn't as easy or quick to use the engine mount. Whatever you do don't use the engine lift ring.

Zac Weidner
11-06-2008, 07:05 PM
I have a 160hp Tri-Pacer and it seems to be the general consensus for the combination of one 1080 and one 1280 on each hydrosorb. I previously purchased two sets of 1080HD's for my hydrosorbs but I don't want a saggy, restored airplane with new bungees. I also don't want to waste a set of bungees. I don't think that the unused set would last till the next replacement, or would they?

Frank Green
11-07-2008, 07:13 AM
A 1080 and a 1280 are both rated at 750s. (1500) 1080HDs are 900 Lbs. (1800) and fit the hydros better. Stick with the 1080HDs.

Steve Pierce
11-07-2008, 07:44 AM
1280HD is rated at 950 lbs. and is 3/4"x8" where as a 1080HD is rated at 900 lbs. and is 5/8"x8". I have put 1080HD on Clippers in the past and had them last 8 years and still didn't sag. Have installed 1080HDs on several Pacers and Tri-Pacers in recent years and they were sagging within the first year. I have read that the rubber compounds changed but don't know that for a fact. If I was going to install bungees on my Pacer or Tri-Pacer today I would install a 1080HD and then a 1280HD over the top. Fits fine and I know it will last.

As far as longevity in storage I don't think $40 several years from now would be worth the aggravation of installing an unknown. I store them in a dark locker between the time I order and install which is short. You might find someone who is fixing to change theirs out that will take a pair of your 1080s.

mjlossner
11-07-2008, 07:54 AM
I put a 1080HD and a 1280HD on our tri-Pacer Last year, don't notice any extra stiffness on sod runways and she sure sets up proud when you walk away her. I feel this is a perfect combination.
Mike

Frank Green
11-07-2008, 08:13 AM
Steve a Clipper is a different gear, narrow. We have a narrow gear 20 and run a single 1380 (1160 lbs.) and am very happy with that. If you have wide gear then yes you need a lot more. If I didn't want any give why have struts at all? I think the right choice is enough but not too much and that varies alot with the different gear combinations and useage that we each have. My 22 original Tri I am happy with 2 1080 HDs. I think alot of the confusion is the regular vs HD.

Zac Weidner
11-07-2008, 06:12 PM
Thanks for all the replies. I think I will probably go with a 1080HD and a 1280HD. Would anyone be up for a trade of one pair of 1080HD's for a pair of 1280HD's?

Lownslow
09-18-2009, 03:05 PM
Does anyone know where to locate that old video showing the bungee installation at the Piper factory? I want to arm-wrestle that guy. I think I can take him now.

Lou S.

Lownslow
09-22-2009, 09:48 PM
O.K. I found it. I know some of you have seen this.

http://www.youtube.com/watch?v=tWZpmu30h94

The old armstrong method.

Lou

Lownslow
09-26-2009, 09:04 AM
Does anyone have experience building a bungee tool utilizing simple leverage, depicted in this video, to install bungees as potent as the 1080HD's? I am considering building one. I have 270 lbs here that is sitting around not doing much.

Lou S.

Stephen
09-29-2009, 11:23 AM
Thanks for sharing the video, this I believe is a common way to install bungees on Cubs. When I was much younger I made a tool like the one in the video, it was a bit exciting sometimes. Installing bungees on Pacers is much less exciting......unless your doing it at Steve's shop. That was a video to see...

Lownslow
09-29-2009, 04:37 PM
If you think I'm smart, you should see my brother. I have him on task to help me design the "armstrong" tool. I will let you know how it works out.

Lou S.

Frogdad
09-30-2009, 12:39 PM
Here are some photos of a home made bungee tool for Pacer hydrosorbs. It works pretty well.
If I had to make another one, I would lower the pivot point so the bungee stays parallel with the tool.[attachment=2:2omcp13y]bungee tool 1.jpg[/attachment:2omcp13y][attachment=1:2omcp13y]bungee tool 2.jpg[/attachment:2omcp13y][attachment=0:2omcp13y]bungee tool 3.jpg[/attachment:2omcp13y]

Lownslow
09-30-2009, 02:10 PM
Thanks for responding, but the pics might come in better 800 X 600. Can't see much the way they are. I do see you are using the idea I have around using an extension handle that slips on the round attachment stud of the hydrosorb. I intend to mount the other end of the hydrosorb at a fulcrum point on a piece of I-beam and set up a trip device on the member from which the bungee is stretched. I am also considering a separate lever instead of the extension handle with an attach point for hydrosorb at the base where the hydrosorb would swivel and slide along the I-beam as the lever is pulled and locked into place. The lever can be designed to enhance the distance of travel from start-to-finish and also be a much stronger means of providing the leverage. The handle you are using looks like it may be under some stress where it slides over the stud of the hydrosorb. Of course, this could be made with heavy material with a tight fit that would not give much. I'm still designing and would like to see the rest of your device.

Thanks, Lou

Steve Pierce
09-30-2009, 02:14 PM
I clicked on the pictures and can see the tool pretty good.

Frogdad
09-30-2009, 02:30 PM
Sorry. I forgot how to downsize photos. See if this is better.[attachment=0:35njdedd]bungee_tool_1.jpg[/attachment:35njdedd][attachment=2:35njdedd]bungee_tool_2.jpg[/attachment:35njdedd][attachment=1:35njdedd]bungee_tool_3.jpg[/attachment:35njdedd]

Lownslow
09-30-2009, 03:59 PM
O.K. The pictures were fine, and the smaller ones are better. Sorry about that. I am still technoligically compromised at times. I really like the tool you have. You just can't get much simpler than that, and I think it will work just as well as you have displayed. I will take your advice on the alignment and have the extension handle fabbed to fit nicely. I have a heavy Wilton vise mounted on my steel welding table that should handle the physical manipulation that will be required, and I will let the brisket, pork chops, mashed potatoes, and Blue Bell ice cream I have consumed since the last Edsel was made do the rest. I'll post some pics when it is done.

Thanks so much.

Lou S.

Tripod
11-15-2009, 07:57 PM
Steve - A wife who can change the bungees on a Tripacer!!!! - You surely are blessed - make sure you treat her right as she is definately a keeper.

Curly

Wow, I've had A & P's who turned a bit pale when I asked them to put new bungees on my hydrasorbs! That your wife can replace bungees, way cool!

Mine? Well, she came from a completely un-mechanical family background and it all rubbed off on her. No problem, though. I take care of the airplane (and cars and house and... ) and she does gourmet cooking every weekend. Good deal, I think. And she will fly with me anytime.

-dave

Lownslow
11-20-2009, 02:59 PM
Has anyone adressed having some slop in the lower attachments of the hydrosorb to the landing gear. The holes in my hydrosorb lower ends seem to be slightly larger than the bolt size. I find it hard to believe the holes became that way due to wear, but I guess it is possible. Almost seems like a bushing could be inserted or drilled out to accomodate a 3/8" bolt? Has anyone dealt with this situation by other means than replacing the hydrosorb?

Lownslow
12-17-2009, 02:05 PM
Here is a tool designed by my brother that worked nicely on two sets of hydrosorbs. He didn't like my idea of an "armstrong " tool (he is a little "light in the shorts" for that design). He came up with his own using a 3-stage car jack and a 1/2"drill - works awesomely. Way to go Clyde!

Lou S.

[attachment=0:3a9hyijw]Airplane pics 013 (Medium).jpg[/attachment:3a9hyijw][attachment=2:3a9hyijw]Airplane pics 017 (Medium).jpg[/attachment:3a9hyijw][attachment=1:3a9hyijw]Airplane pics 019 (Medium).jpg[/attachment:3a9hyijw]

Lownslow
12-17-2009, 02:06 PM
More pics[attachment=1:kqid5iag]Airplane pics 015 (Medium).jpg[/attachment:kqid5iag][attachment=0:kqid5iag]Airplane pics 025 (Medium).jpg[/attachment:kqid5iag]

Steve Pierce
12-17-2009, 03:18 PM
Now that is slick.

Curly
12-17-2009, 11:25 PM
Jeez Lou, your game - "A bit light in the shorts" comment to one of my brothers would have me ducking the inevitable right cross! (only jokin' Chops) :lol:

Good bit of gear tho' - well thought out.

Lownslow
12-18-2009, 12:24 AM
I did say he was smart. We have an "understanding". It has to do with mom liking me better growing up. He doesn't handle a crosswind very well and we have to tie him down on the very windy days. :o

Lou S.

Lownslow
12-18-2009, 02:46 AM
Greetings there Curly!

From Victoria, Texas

Lou S.

MN_flyer1
07-13-2010, 07:57 PM
After seeing this video my brother and pals managed to build one that works. Here are some pictures. I messed up and didn't get any pictures in use. It works the same as the video. With the short hydrosorbs you have to use a cheater pipe.

I hope this is good enough to get the idea.

video link: http://www.youtube.com/watch?v=tWZpmu30h94 (http://www.youtube.com/watch?v=tWZpmu30h94)

Terry E
07-20-2010, 10:34 PM
I don't want to cheat the Stuarts out of selling there tool but I have one and it works great. If anyone needs to use it , for shipping its yours to use , I mean its nice to have the tool and I don't need to use it every day so PM me if you would like to use this great tool and we all can share it.

Terry

Steve Pierce
07-21-2010, 07:09 AM
Thanks Terry. I am sure everyone will appreciate your offer.

seagull
03-11-2011, 07:48 AM
lownslow, just now wanting to change my bungee cords on my 50 pacer, intimidated by them massive cords and saw your post. Any possibility of getting some of your pictures on the 3-stage car jack

Seagull

Bob Mac
03-11-2011, 06:02 PM
Is anybody still using the Tietmeyer tool on removed hydrosorb/bungee get togethers?

Lownslow
03-11-2011, 09:05 PM
O.K. I finally got to my home PC to get some pics out. This unit was made from a 80 something Ford Bronco 4X4 by Clyde "The Glide". Works like a charm.

Lou

seagull
03-14-2011, 08:24 AM
it looks great, managed to borrow a dangerous bungee tool, though it could be the last bungee cord I'd ever change. Will have to try a replicate your tool. Thanks for the effort
seagull

seagull
03-14-2011, 08:29 AM
Lou thanks for the pics. Mange to borrow a "suicide" bungee cord installation tool. Thought it might be the first and last bungee cord I'd ever install. Your looks a lot safer and certainly a lot less muscle power involved.
does 'Clyde the glide sell these units?

Seagull

Bob Mac
03-16-2011, 07:10 PM
Installed the 2 1080HD's on each of my hydrosorbs yesterday using the Tietmeyer tool that I have had since early '80's. Went very well but I have a warning for you youngsters: This tool is to a great degree "armstrong" and I can attest that the arms ain't as strong at 77 as they were at 50!! but neither is the brain.
Bob

Nathan Hiebert
03-17-2011, 11:42 AM
So I'm just wondering...Do you remove the old cords with the installation tool as well? If you were a real man, you'd just cut them off! (Just kidding) :)

MN_flyer1
03-17-2011, 12:54 PM
Since they are made of a pile of rubber bands cutting through them is generally uneventful.

Bob Mac
03-17-2011, 01:20 PM
Many years ago I bought a box of 1000 single edge eazor blades.
Since this is St. Patricks day I alwayts tell people the reason I talk so much is that my Irish mother told me that every 100% irish kid (like me) is born with an inexhaustable supply of words and must use them all up if he wants a happy hereafter.
Same with razor blades.

Nathan Hiebert
03-17-2011, 09:36 PM
In A&P school, they warned us not to cut the bungees for they would violently snap back. Is this not true?

stevesaircraft(Bri)
03-17-2011, 09:57 PM
I clamp the ears on one end of the hydrasorb in a vise and cut the cords off one at a time using my very dull pocket knife.....the vise jaws keeps the bungee cord from snapping around....Just don't get in a hurry and the cord will release its energy and stretch out slowly...

Brian.

MN_flyer1
03-17-2011, 10:05 PM
I will be honest I have not done a lot of them. The ones I did last year cut off very easily with a pocket knife. They were pretty old so that may have been a factor. As you cut into them, by sawing a few strands at a time, the remaining cord bands continue to stretch. Eventually they stretch to the point where there is not much power left. I would recommend a slow cut vs using a bolt cutter type of shear. Also if you can clamp the strut in a way so that any power released is directed away from you that is best. I am sure many on here have done it many different ways.

Bob Mac
03-17-2011, 11:11 PM
I have found that the easiest way is to use one of my single edge razor blades and slowly cut a few strands at a time. This eliminates any dangerous snap-back and goes easily and quickly. I can do this while holding the assembly in my non-cutting hand.
Just be careful.

awright
03-21-2011, 06:29 PM
I would love to be able to use the bungee tool. I have a 1950 PA-20 that is ready to have the bungees installed. my phone number is 916-601-0664. Please let me know what you would need from me.