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 Post subject: Aileron weight.
PostPosted: Sun May 26, 2013 12:58 pm 
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Location: Montreal, Canada
Hi!

Quick info what do you think about the third hole on the bending square tube.
Is it possible that the third hole is a starting point for a possible rupture?
I'm not a Thorp specialist but I never want to loose this weight on flight.

Image

Image

I need to sand blast the arm and see if some small crack is begening.
I want to know your idea about that!
Thanks again.

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Thierry
French Canadian T-18
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Rich Brazell
 Post subject: Re: Aileron weight.
PostPosted: Sun May 26, 2013 9:53 pm 
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I would be very cautious ! I am not a welding guy , but it may be possible to close up the 3rd hole with a torch ? Or cut and splice a new piece in . Or make an entire new weight/arm . Or buy one ?

RB O0


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dan
 Post subject: Re: Aileron weight.
PostPosted: Mon May 27, 2013 9:48 am 
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That's a mild steel Tube Thierry, The hole is not in a spot being of high stress. Clean it up,spotless, 45degree countersink the hole to get into some fresh material and Tig it closed, Make sure there are no cracks, make sure the tube doesn't get hot enough to loosen the lead weight at the end of the Tube........Dan


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dan
 Post subject: Re: Aileron weight.
PostPosted: Mon May 27, 2013 9:59 am 
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You can also put a piece of solid rod in the hole that runs from one side to the other and use it for filler,It would make the hole easier to fill and allow for less heat to close it up,weld bothe ends of the rod this will also reinforce the area with the hole in it if you are worried about the integrity of the tube. Dan


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Pacer 20
 Post subject: Re: Aileron weight.
PostPosted: Mon May 27, 2013 5:02 pm 
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Location: Montreal, Canada
I open my AC43-13 and I see some interesting document. Dan your apsolutly true. I think a small welding with a inside doubler was correct.
I send you pictures after the reapir!!!

Merci.

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Thierry
French Canadian T-18
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ljkrume
 Post subject: Re: Aileron weight.
PostPosted: Thu Apr 03, 2014 1:38 pm 
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Hey guys,

Tried about 5 attempts to pour lead into a plaster mold with steel arms in it. Made nice patterns, nice mold, etc., but casting lead just doesnt work for me. I think plaster has too much air or something and I get a lot of bubbling. Let plaster sit for a week and in the oven 250F over an hour to get rid of any water vapor and still pretty poor castings. I've seen some that others have made and they look pretty rough too. I was hoping to come out good. Searching old newsletters I find nothing about making these.

Anyone with ideas on this, or a source of good ones to put on a new bird, please let me know. By the way, I recommend anyone to look back at the old newsletters. It's been a while for me and they're really fun.

Thanks, Les Krumel
Albuquerque


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Bill Williams
 Post subject: Re: Aileron weight.
PostPosted: Thu Apr 03, 2014 1:52 pm 
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I made a mold out of thin steel and shaped it like a cookie cutter. Foiled taped a flat piece steel to close up one side and poured. I also tinned the square tube where it attaches to the lead.


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jrevens
 Post subject: Re: Aileron weight.
PostPosted: Thu Apr 03, 2014 3:00 pm 
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Les,
In my experience, the trick to getting a good lead molded piece is to pre-heat the mold. You can't do that with plaster -because it hasn't got enough mass & other reasons. Steel or even aluminum works well with lead. If the mold is cold, the lead starts to harden as soon as it hits, causing stratification, possible voids, etc. If the mold is not too thin & has some mass, that helps too because it doesn't cool off as quick. I'll heat the mold to 400 or 500 degrees in the oven before taking it out & pouring the lead. I've even heated molds on the range top in the kitchen, while melting the lead right there also. My wife loves that.
It is important to tin the steel arms before molding the lead, as Bill said. Don't splash, but don't "piddle" around - pour it right in so that you're never pouring lead on top of lead that has already started to solidify.

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James Grahn
 Post subject: Re: Aileron weight.
PostPosted: Fri Apr 04, 2014 9:47 am 
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Or you can call Mike.
I'll have the weight molds shortly (as soon as Mike gets healthy) and I'll pour you some.
Cubes


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ljkrume
 Post subject: Re: Aileron weight.
PostPosted: Wed Sep 17, 2014 11:58 pm 
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Hey guys,

I'm still in need of aileron weights. If none are available I'll try milling a mold from aluminum. I'm down to a short one-page checklist of things to do before N48LK is ready for airworthiness inspection. Getting exciting now.

Thanks.
Les Krumel,
Albuquerque


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fytrplt
 Post subject: Re: Aileron weight.
PostPosted: Thu Sep 18, 2014 6:19 am 
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Les,

I made my molds out of some scrap strip steel. I cut a notch in the cookie cutter looking mold to let the arm with pin in. The whole thing was placed on a plate for the pour. Easy to knock it out once cooled. Don't make the project harder than it is.

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Bob Highley
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leewwalton
 Post subject: Re: Aileron weight.
PostPosted: Thu Sep 18, 2014 8:29 am 
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Les, I have a few sets of spares. You're welcome to a set.

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Lee Walton
Houston, TX
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James Grahn
 Post subject: Re: Aileron weight.
PostPosted: Fri Sep 19, 2014 10:21 pm 
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I can make some too. Let me know.
Cubes


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ljkrume
 Post subject: Re: Aileron weight.
PostPosted: Mon Sep 22, 2014 7:59 pm 
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Thanks for the response guys.

Bob, I tried 5 times with the mold I made and a couple of times the problem I had was springing a leak. Just a small crack and what a mess! I think I did good with the rest of the project and wanted to a nice job with this too. I might be able to get it but I'm real close to the finish line; the best thing at this point is just to get a pair already made.

Lee, if you already have a good set please PM me and let me know what I need to do.

Thanks again,
Les K


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