Rail button installation questions

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billdz,
Parallel is not usually the problem although it is not hard to twist out a button, usually the bottom (first one on the rail), while trying to line up the second. A helper to line up the buttons is a good idea especially on larger rockets. After the buttons are on the rail it is a good idea to let just one person guide it down the rail. At least for a rocket weighing less than 20 pounds or so. When others are helping you cannot tell how much resistance there is when sliding it onto the rail. I like to hang it on the rail and allow it to slowly slide down it as the rail is lifted to vertical letting it find it's own course. The rocket needs to be parallel to the rail but also the screw that holds the button on needs to be perpendicular to the surface of the rail. There is a path of least resistance. Gently move the rocket slightly side to side until you find it.

There is a lot of good advice here.

Thanks for the replies, and special thanks to Scott for offering to replace the airfoil guide. I have had 4 issues since February, two with rockets I built and two with pre-built rockets that I purchased. The first time, I noticed on recovery that one of the rail buttons was gone, apparently it the screw came out during flight, as there was nothing but a hole. When I went to replace it, I started to put some CA in the hole so that the screw would hold tighter, and that's when I was told not to use CA because it might bind the button, which is supposed to be loose so it can spin. The second incident happened a couple of months later, nothing major, the screw had come partially out and the button was tilted sideways. Then last Saturday two separate incidents. First the top of a round button broke when loading the rocket onto the rail, see picture. Later the top portion of an airfoil guide broke, also when loading, I recall hearing the sound of plastic cracking as the rocket was sliding down the rail, even though I was trying to be extra careful in light of the first incident, see attached "before and after" picture. Joe may be onto something when he says, "If they are breaking you are likely binding them when you are loading. It's easy to do. There is a learning curve going from lugs to buttons." Please explain further about "binding them when loading," not sure what that means. I see that some people spray silicon or WD-40 on the rail before loading, maybe that's what I need to do. I did notice on both occasions that the rocket did not seem to be sliding down the rail as easily as usual.
 
I've always loaded my rockets on top of the rail, and never broken a rail button. The only damage I've ever done is to scratch the paint with the rail.

P1100057.JPG

IMGP3789.JPG

IMGP2399.JPG
 
The idea of placing the rocket so it hangs on the underside of the rail makes sense. Wonder why more don't do it this way. Seems like most folks put the rocket on top of the rail, e.g.,
Snip...

I think that the biggest reason is the direction that launch pads tilt for loading. The slot on the rail usually faces the spectators so the rail doesn’t obscure the rocket. It’s a violation of the Safety Codes to point a rocket towards the spectators (for good reason). So tilting the rail back for loading results in the slot being on top of the rail, requiring sliding the rocket onto the top of the rail.
Pads that swivel, such as the Quad Pod, can be swiveled 180° and then tilted away from the flight line to load a rocket on the bottom of the rail. Pads such as the Coker pad cannot be swiveled so the rocket will always be loaded on top.


Steve Shannon
 
Hey Billdz - my preliminary failure analysis, (well more of a material analysis).

First glance - these pieces look to be printed from an FDM type machine! That would really explain very clearly to me the delicate nature. I will have better confirmation in the next two days.

I have captured some spectra on an FTIR machine to identify the actual material used, which could help us also prove if it was printed or not, but importantly what the heck the material is. I ran out of time tonight and need to run more samples tomorrow
 
I didn't see any fragments of a round button, I will check the envelope again tomorrow. It did look like the package had been "compromised' somewhat in transit. The envelope inside the envelope had fragments in it that all appear to be from a printed part. I am really being objective here and not saying this for any other reason than what I feel technically reasonable for safety, etc....but I would never trust a printed rail guide on anything that had the weight or power to need a rail guide. I would probably not even trust a printed guide on an estes bird. Especially not the materials generally being used in hobby level printers.

OK, tomorrow will be interesting! I look forward to (hopefully) getting a good match on the spectrum from the fragments I have. My money is on ABS.....or PLA. I hope PLA is in the library since I don't have any to shoot a sample of.

Talk to you tomorrow! Hey by the way did you get anything in the mail yet?
 
Hey! Don't mistake the apparent tone in that last reply! I re-read it and sounds condescending to printing or something. I was just a bit surprised if someone is selling printed rail guides.

If they were from Wildman I would be surprised.....Utmost respect for him and I do not think he would do that. I think it is an imposter.

Love you MAN!!
 
The round button pictured in post #15 of this thread was in the envelope. I'm not up on 3D printing so I don't know the meaning of things like ABS, PLA, FDM, or FTIR, but I'm sure you'll figure it out.

Have not received anything from you in the mail as of today, when did you send?
 
Hey! Don't mistake the apparent tone in that last reply! I re-read it and sounds condescending to printing or something. I was just a bit surprised if someone is selling printed rail guides.

If they were from Wildman I would be surprised.....Utmost respect for him and I do not think he would do that. I think it is an imposter.

Love you MAN!!

Also, strength of printed items depends on the orientation of the part being printed (the lay of the layers in regards to eh forces ieng applied. Buttons will fail, if the layers are horizontal, like the button was 'as intended to be installed' as it was printed, vs it being printed so the layers are 90° to the installation / stresses.. But then the wedge of a flat head screw would drive the layers apart at one point..

just saying. And I do agree, printed parts are nice for show & tell..
 
Also, strength of printed items depends on the orientation of the part being printed (the lay of the layers in regards to eh forces ieng applied. Buttons will fail, if the layers are horizontal, like the button was 'as intended to be installed' as it was printed, vs it being printed so the layers are 90° to the installation / stresses.. But then the wedge of a flat head screw would drive the layers apart at one point..

just saying. And I do agree, printed parts are nice for show & tell..



yes EXACTLY! I take advantage of printing where necessary and truly advantageous. I use a Fortus 400 which can print (FDM) Ultem, which I have used to make "soft jaws" for machining complicated parts, as well as nylon, ESD material, etc......oh of course the typical ABS. Have made end-product by printing for covers, etc. Even some mechanisms it has proven useful. Great technology!
 
it is what it is.. We have a Makergear Mk2 and a Fusuion360. the Fusion sees a lot of use, and we use a lot of PLA. We do plan on using ABS at some point, (hopefully) in the new year.

I remember a conversation I had with a friend. His 'bar friend' was all up against China, and the "crap" they churn out. He was going to get himself a 3D printer, and go up & down the street (this was in a bar on Crescent street, a street in Downtown Montreal that is wall-to-wall bars) selling his 3D printed-logo-encrusted shot glasses, and undersell China (or whomever make promo shot glasses). He was going to make a mint!

Then I explained a few things to him, as he was also looking for my advice, to see it it was indeed viable, and why more people aren't taking advantage.. I told him straight up. A typical shot glass is gonna take about a half hour to print. How many would a bar want? Are they meant to be a give-away? And who / where will you get the model / file for the logo'd shot glass? And, it's printing in plastic. You'll need to get "FDA" approved filament too.. he soon saw the light..
 
Just to demystify things, I'm the previous owner of said rocket, and yes, they are the 3D printed ones from Wildman.
 
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