HS710 Replacement

[Naruto]

Hi Guys,

I new here. I will probably have many questions. I received my empennage kit last week and have been working on the horizontal stabilizer. My edge distance on the hole I drilled through HS 405 ended up putting the hole too close to the edge of HS 710 I believe. The left side came out fine. My question is since there are like 7 other rivets that attach HS 710 to HS 702 front spar, should I still replace the bracket even though the edge distance on HS 405 is fine. If its recommended to replace HS 710, can I run over to Home Depot and buy some angle aluminum stock and make my own HS 710 rather than wait a week to get a replacement one from Vans?

I'll get a picture of it and post it tonight.

 

[sprucemoose]

Welcome to the club.

You really need to replace it. You're not really a builder until you've made at least three of the @#$% HS-710s anyway. If you can post a picture that might help, but I think just about everyone here can picture what you're talking about, because we all screwed up that same part. It's a right of passage.

You cannot use Home Depot angle to make a new one. Aircraft aluminum and hardware store aluminum are two very different things. Different alloys, plus aircraft Al angle has a radiused inside corner, while the cheap stuff does not. You may be able to find a local source for aircraft Al, and it is perfectly acceptable to roll-yer-own, as long as you use the right material.

 

[Brantel]

Just go ahead and buy the right parts from Vans. Get used to it it won't be the first time. I killed my first one as well, lots of people do. There are a couple other rights of passage that you will find as you finish your emp. let us know when you find them.

 

[jmbaute]

Me, too.

My second replacement just arrived yesterday, in fact!

Once you see how it all goes together it underscores that you have to be conservative trimming this angle. I will be more careful this time.

One thing to keep in mind is that there is plenty of other stuff you can move on to while you wait for parts. I started my rudder...

 

[Naruto]

Thanks for the input guys, I will post a pic as soon as I get home from work. Maybe what I think is bad might not be so bad. I was hoping to get the HS done this weekend. Its kind of strange because the left side came out just fine and I used the same technique in measuring the dimensions. Why does vans give you measurements that would possibly make a part unusable? I also have a pretty good gouge on one of the HS fiberglass tips right out of the box that I noticed when I inventoried the kit. Should I send it back to Vans for replacement or should I just fix it myself when I fiberglass the tips later on. I'll post some pics of it too tonight.

 

[alpinelakespilot2000]

One tip for the many parts you are going to fabricate in the project...

Whenever possible, cut all parts oversize initially. Then, once you have all the holes drilled and mated to other parts, then cut or file down the excess. In almost all cases you can make parts bigger than Van's drawings allow, but often you cannot make them smaller at all. I finally realized that going big to start was the way to go when I got to my fuselage. Realizing it earlier would have saved me a lot of grief, $$, and more shipping expense $$!

Agreed that you need to order aircraft grade aluminum.

Finally, when in doubt about edge distance, talk to Van's.

good luck.

 

[Brantel]

Why does vans give you measurements that would possibly make a part unusable? I also have a pretty good gouge on one of the HS fiberglass tips right out of the box that I noticed when I inventoried the kit. Should I send it back to Vans for replacement or should I just fix it myself when I fiberglass the tips later on. I'll post some pics of it too tonight.

There are lots of places where you must look ahead and anticipate this. If you don't, it will cost you big time. Learn it now while the parts are cheap.

As far as the tip, no fiberglass from Van's is perfect, you will have to spend allot of time filling, sanding, filling, sanding fitting etc when you get to that point so I would say that you will need to just fix it yourself.

 

[truflite]

Replacement parts

Five will get you ten that you buy a replacement elevator trim tab skin. Another rite of passage.

Dave

 

[Brantel]

Yea,

Vans should have a list of the most common "replacement" parts so you can go ahead and add a couple of each of them to your emp order to save on shipping.

 

[osxuser]

Five will get you ten that you buy a replacement elevator trim tab skin. Another rite of passage.

Dave

****, am I not a builder? I've screwed up my share of things, but managed to walk on those two . I ALMOST blew the edge distance on the -710, but caught myself before it was too late (measure a bunch of times, drill once). The Trim tab was probably one of the easiest parts of the project once the tabs were bent.

Of course, I just got $30 worth of new rudder stiffiners...

 

[Naruto]

I called Vans tech support and explained that the edge distance was not where is should be on HS 710. I explained that the edge distance on the rib HS 705 was fine and per the drawing. I ask him that if I buy a new HS 710 bracket and a HS 705, then make a hole the proper edge distance on HS 710, that will make my edge distance on the HS 705 rib to close and not make it proper anymore. He said that as long as the HS 705 rib edge distance was fine, the reinforcement bracket was pretty beefy and would be OK even though you don't get double the diameter of the shank from center of hole to edge on HS 710. He said it was a tight fit but was more concerned with the rib edge distance rather than the reinforcement bracket. I feel much better now. Thanks guys for all your support.

 

[jmbaute]

I'm sort of curious about this since I got the opposite answer from them two weeks ago. Of course, I did mess up my 710 pretty bad.

Just took the new one out of the vise 30 minutes ago...iteration III.

I think my problem on the first two was newbie + power tools, and not taking my time. On the first one, I just plain cut off too much, the second was better, but when I was ready to do the final assembly is when I noticed the edge distance...just barely too little material left.

After seeing how the assembly goes together, it seems to me that there really is no reason to trim off any material from the bottom (side towards the middle of the spar), other than making the part symmetric and saving a few grams.

Oh well, they probably have their reasons? (to sell replacement parts?)

 

[Naruto]

I agree. I don't really see a reason to trim the inside of HS 710 when only the outside has to fit the edge of the front spar. I think the hole on HS 710 is suppose to be before you trim the 2 1/2" taper on the ends, so there should have been no material really cut off. I think when I used the scotch bright wheel to smooth everything down, it took off more material than I realized. I have about a 1 to 1 1/2 " edge distance and feel comfortable with leaving it there based on what Vans told me. It looks worse when you try to compare it with the other holes all lined up in a nice row when this one hole looks really out of place. The plans do say that the hole is not centered on the bracket. Even if I did get new parts, I don't see how I would not mess up HS 705 rib (or is it HS405?) edge distance since its already a 1/4" away from the edge and moving the hole on HS 710 in more would make the hole on HS 705 move out.

 

[Naruto]

Here is a pic of what I've got.

 

[n5lp]

Here is a pic of what I've got.

My vote is to redo that. I don't know if it would fall apart, but it doesn't look like an airplane part and you will always know it is there.

 

[Naruto]

If I get new parts and I move that hole down more, it will cause the hole on HS 405 (not HS705) rib to move closer to its edge were it wont meet spec. What a conundrum? The bracket looks a little wavy but that just a shadow and uneven priming. I took the pic about 30 seconds after I primed it. I put a straight edge flush with the straight piece and compared it with the area that I smoothed down and there really was vary little material scotchbrighted (is that a word?) off, so a new part would not look much different. HS 710 is a heck of alot thicker than HS 405.

Here is another pic with different angle. Its a little blurry

 

[Paul Thomas]

I don't know if it would fall apart, but it doesn't look like an airplane part and you will always know it is there.

That attitude has caused me to replace parts that didn't need to be replaced, bu it makes me sleep better at night. My airplane will be perfect

 

[osxuser]

That one is farther off than mine. I'd be tempted to "Build-on" in that case, but whatever makes YOU feel comfortable. I'm no engineer, but my guestimate is that would be fine...

What I don't understand quite that well from this whole dillemma is why Van's doesn't have you drill from the HS-710 side into the rib instead of the other way around... but maybe I'm just not looking at the big picture.

 

[Naruto]

Well guys,

Thanks for the input. I decide to build on and spent a good twelve hours in today from noon to midnight. I did all the riveting myself as the wife was out most of the day. All riveting occurred today with a avery hand squeezer and 3x gun. My hands hurt something fierce. That inner rib HS 707 sure was tough doing by myself. The wife is definitely helping on the right side. I started on may 30th, 2007 and hope to have the HS done tomorrow. Thanks again and I am sure I'll bugs you guys some more.