Can someone point me to instructions on the proper safety wiring of worm clamps? There's nothing in AC43.13 that I can find.
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Can someone point me to instructions on the proper safety wiring of worm clamps? There's nothing in AC43.13 that I can find.
Might that be because safety wire is not required? Worm clamps have tremendous mechanical advantage and I have never seen one safety wired on a general aviation aircraft.
What is being secured by the subject worm clamp?
Best of luck,
Wes
N78PS
I figure someone would have figured out a need and method, so I searched Google:
http://avidflyer.wikia.com/wiki/Safe...m_Drive_Clamps
I worried about the same thing. But I worry about everything. So I installed some anti-tamper paint that comes in a tube. I have yet seen one turn or loosen up. After I did this, I would take off then land, get out and check the clamps. After about 1 hour of doing this I called it good to go. In 45 hrs flying this summer I never had one loosen. It was easy to check with the paint on them.Quote:
Originally Posted by Bob Collins
Everytime I look at the paint I think..saftey wire those, but then I don't. I guess I have never seen one loosen. I bet the first time I do I will be safety wiring these. I have these clamps on the rubber for the intake tubes.
I never replaced those rubbers and no matter how tight you tried to get those clamps the rubber would slide right off the tube. I had it happen on takeoff. Engine never died but it was a scary time for sure. I replaced all rubbers and propblem solved. I also replaced all worm drive clamps with new. I will reuse them once maybe twice then they get replaced.
How I do it..
H.A.S.
I check all of the ones in the engine compartment at oil change, and any others I can get to during annual. I have found a couple on the intake tubes a bit loose, probably from vibration or the rubber shrinking.
When building my hotrod I used hoses and ends that used no clamps. Once the hose was installed it would never leak. They cost alot but seemed well worth the money. I did this for the looks. I won 3 first place trophies with this truck. One was at the Nationals.
I thought if I ever fly a plane I will use these. I have not changed my oil lines out yet but they are getting replaced with this style hose and ends. I picked mine up at a Hotrod shop that is where I will buy them again.
What brand hose ends are you using?
Here is a short video of this truck. This video is kinda shakey. I had a broken back and it was hard to walk, hold my cane and film. I am not sure if you cans see these lines. They are blue with red ends. I built this truck in 3 months, I hung the body from the rafters in that garage. The day they let me out of the hospital I was out in the shop working on my truck. Screaming from pain but with a big smile on my face. I do miss that truck. I sold it for the parts I had in it.Quote:
Originally Posted by 1600vw
http://www.youtube.com/watch?v=HRhDrt87ojY
I will go into the hotrod shop and get some pics of these. I will try and do this tomorrow. They are pricey but worth every penny.Quote:
Originally Posted by Mike Switzer
That is correct, the material can cold flow making the clamp seem loose even though the screw has not moved.Quote:
Originally Posted by Mike Switzer
Well, here we are deep into the thread and we've talked about everything BUT safety wiring worm clamps.
The reason I'm asking is I'm installing a Reiff preheating system and the instructions state that the worm clamps holding the cylinder bands should be safety wired because they will work loose and break.
The system costs about $500 so I'd kind of like them not to do that.
Worm clamps are not commonly safety wired.Quote:
Originally Posted by Bob Collins
If so why not ask them? I have seen a few Reiff systems installed on planes & I do not remember seeing safety wires. Maybe they have recently started recommending this, in which case they probably have a recommendation on the proper procedure.Quote:
Originally Posted by Bob Collins
Bob, did you go to the link that Marty put in post #3? I looked at it and the solution seemed reasonable to me.Quote:
Originally Posted by Bob Collins
An old reference I have says "AN737TW Hose Clamps are for use on fuel, oil and coolant lines; clamps may be tightened repeatedly while in service. No lock wire required."
So I'd say there is no standard method of safetying a tangential-worm clamp. Absent instructions, I think you can come up with your own method/technique or just copy someone, like the link in #3.
On closer examination, some of those examples are not good.Quote:
Originally Posted by Auburntsts
I will not be posting those pics for a while, I came down with this flu going around.
I got these lines and ends from Mullens Hotrod shop here in springfield IL. they are located on cook street.
If you give them a call talk to Dwayne. Tell him what you are looking for he will help you.
H.A.S.
This stuff is called "Push Loc" Its all AN and they do make pipe thread ends to go into blocks and such. You can get this with rubber hose or the metal hose. Takes no speacial tools to install. Just make sure you have everything correct before putting your ends on, once on they can not be taken off. No clamps and will never leak.
Do a search for Push loc fittings you will find what you need and no more clamps. You can thank me later......
Bob's situation is a little different. The Reif cylinder heating bands are attached worm clamps, so not using them isn't an option. Giving Bob Reiff a call and asking for his advice is probably a good suggestion.Quote:
Originally Posted by 1600vw
Bob Reiff will tell you that any problem you have with the units as sold are purely incompentence of the user/isntaller and that there is no way there could possibly be a problem with the design or manufacture.
THe official line on screw clams was already posted. You need to check them for tightness periocially. While this is absolutely essential if it were something like a hose clam that could lead to leaks or the hose blowing off, on the Reiff it's not a real big problem. It's just going to let them slip a bit. They probably will still work fine and I can't imagine a safety issue for flight. Of course, if you're really paranoid, get a TANIS that uses more conventional hardware to mount.
Hi BobQuote:
Originally Posted by Bob Collins
There are 2 quite different purposes in safety wiring worm clamps.
The first as the link in Marty's post shows is to safety wire the bolt so it doesn't come undone and the other is to capture the clamp in the event that it comes off either due to coming undone itself or shrinking of the material it is clamping.
So it depends on the purpose of your question.
As Marty has covered the first I'll do the second.
The main concen with the clamp coming adrift is it falling onto something that can cause damage. Perhaps because they have a background of engines being mounted in pusher configurations some Rotax people safety wire the clamps to stop them going through the prop. I know of no specific methodology as the clamps vary so much with the manufacturer but I basically just use common sense, for the clamp holding the aircleaner I find a hole in the clamp, usually through the screw mechanism somewhere which I can pass the wire through, or if there's a waist, just tightly wrapped around the screw housing and then run it back to the carb which has an ear for the aircleaner safety wire, twist up with minimum slack.
Hope this helps.
Mark
Actually our instructions do not say "they will work loose and break".Quote:
Originally Posted by Bob Collins
Per our Installation Instructions:
4. Safetywire the clamp screws to insure they will not vibrate loose. If they vibrate loose the heating elements will burn out. Put the wire in the screw slot and around and through the screw housing.
I agree... why not call us and ask if something is not clear in the instructions, rather than posting a question on a forum?Quote:
Originally Posted by Mike Switzer
We have always required that the screw be safety wired, since introducing the cylinder heat band in 1996. If you see any in the field that aren't, it's because the installer didn't follow our instructions.
Safety wiring a hose clamp is very simple and quick, and will insure that the clamp does not come loose. If it does, the heating element might not be in good contact with the cylinder and it will overheat when you plug it in, and it will burn out. It's not an airworthiness issue, it's a heater lifespan issue.
The photos in post #3 look good... "Putthe wire in the screw slot and around and through the screw housing."Quote:
Originally Posted by Auburntsts
Let's just slow down a bit, Bob, and take some deep breaths.
This thread is three months old. If you go back to the original date of the post, you'll note that it was when your email systems were down and you weren't getting any email; at least that's what you told me when it came back up and you answered a few emails a few days later (and after this post). I could have called, but my deafness makes it difficult for me to understand people. And "how to safety wire a worm clamp" seems to be right up in the wheelhouse of the homebuilders who frequent an EAA site.
It's a great place to get simple questions answered. It's not an assault on your business (which, you'll note I didn't mention in the original question and I have several worm clamps all over the airplane, not just yours).
You'll note that Marty answered my question within 3 hours of when I asked it. That's the kind of attitude I like about EAAers.
You have an excellent product. I like it. But I'm not that keen on getting slammed by a guy I just gave 500 hard-earned dollars to. If your business is that good,congratulations. Keep up the great work.
But everybody who looks at my system -- and several have so far -- always wants to know where I got it. They're potential customers. Which makes me one of your potential salesmen. If I recommend doing business with you, then they become your potential salesmen. So be nice to your salespeople. Or they'll sell for your competition.
Slammed?? We don’t understand why you say that, but sorry you took it that way. That was not the intent. The intent was simply to correct misinformation about our installation instructions that was posted on a public forum, and which lives forever in the archives. We just want to insure that current and future readers have accurate information. Many folks use forums as an information resource, and it doesn’t do them or us any good to have info in the forum archive that is not accurate. In this case it appears to be an unintentional error of omission in failing to mention that our instructions do describe how to safety wire the clamp, and a misstatement of what the instructions say can happen if you don’t.
A second reason for posting was to make sure you had an answer to your question. In your post #11 it did not sound like you were satisfied with the responses so we wanted to indicate our approval of the reply in post #3.
The third reason for responding was to suggest that if you or any other forum users have questions about installing any product, the logical place to start is the folks who made the product. Per the statement at the top of our Installation Instructions…
“If any of these instructions are unclear, please call for clarification before beginning”.
We are the experts about our products, and are the best information source.
I was concerned about your comment that you posted your question here because our email was down, so I checked our email files. We got an email from you on Saturday Jan 5 asking about the harness routing, and we replied on Tues Jan 8. Normally we reply to emails within minutes or hours, not days. So in the reply we stated “Sorry for the delay, we’ve had PC connection issues since Thurs so are a bit behind.“. Then you called us later on Jan 8 to order some harness extensions. To try to make up for the two day response time, we waived the normal $10 charge for the extensions. The point is, if you had another question on Jan 13 when you posted it here, phoning or emailing us would have worked fine and you would have received help immediately or almost immediately. Good customer service is our goal… if a customer feels it is necessary to post an installation question on a forum and wait days or weeks for answers from third parties, that’s not our idea of good service. We also recognize that if there is a question as in this case, it’s probably an indication that our instructions are not clear enough and maybe we need to add a photo or something.
Regarding our delayed response here, it wasn’t 3 months. Wasn’t even 2. The initial post was Jan 13 and we replied March 7. The only reason our reply was delayed that long was that we were not aware of this thread until around March 1. We don’t normally monitor forums, but sometimes receive tips from friends and customers when they see a discussion they think we should contribute to. It then took several days for EAA to register us so we could reply.
The system you bought was $435, not $500, but that’s still a significant sum for most people and we agree with your point that it’s worth the effort to install it well to maximize its lifespan.
We do appreciate all of our customers, and their word of mouth endorsements which have allowed us to grow with very little advertising expense, which allows us to keep our prices down. But if some of the word of mouth on forums is not entirely accurate we hope most people will agree that it’s only fair that we have an opportunity to address it. We assume any such misstatements are unintentional, and we would hope that most people would not view this as “slamming” a customer, or not being “nice”.
Just want to end with a note that we appreciate EAA allowing us to post this. (Rule 8. Please do not use EAA Forums to advertise or promote businesses, organizations, products or services through means such as posting notices on forums. Informational posts are allowed in response to questions or comments). When we recently replied to several questions & statements regarding installing our systems that were posted on another homebuilder forum by you and others, we were told that we violated their rules. It’s certainly the forum owner’s prerogative to set whatever rules they want and we will obviously respect their wishes, but we think the primary value a forum like this offers is the presence of knowledgeable people to answer questions, and policies that drive those people away diminishes the value of the forum as an information resource.