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Avid Fat Bastard

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Posted

Howdy Folks, hope there's room for one more fat bastard in here,I just picked up an unfinished Avid plus with a Ea 81 Subaru on it, the owner has lost interest so hopefully me an a few friends and of course you guys can get it flying. Doug pointed me in the direction of this forum (thanks again) and it has ton's of great information, I will probably have a bunch of questions down the road.

Take Care, Willis

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Posted

Howdy Folks, hope there's room for one more fat bastard in here,I just picked up an unfinished Avid plus with a Ea 81 Subaru on it, the owner has lost interest so hopefully me an a few friends and of course you guys can get it flying. Doug pointed me in the direction of this forum (thanks again) and it has ton's of great information, I will probably have a bunch of questions down the road.

Take Care, Willis

Welcome to the group Willis. One question, who is DOUG? Again welcome. Russ.

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Posted

Yeah, which Doug are you refering to?? Hopefully you didnt pick up his fat bastard. If so we are for sure gonna be sending Russ over to have a talk to that boy!

Welcome to the dark side! Hope you enjoy the build and then the flying of your Avid. Feel free to hang out on here and post up pics of the build and ask any questions. Pretty friendly and helpful group here if you can take a shot to the ribbs now and again if your work progress slows too much :lol:

:BC:

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Posted

Opps maybe I got the name wrong it was dholly that pointed me to this site from the kitfox forum,was getting some pretty negative replies over there when I mention Subaru Avid. The Avid I picked up was from Ivan Christenson in B.C. Canada, He said it was one of the original first five Avid plus they made. I got my nick name screwed up it is supposed to be Marshawk, does anyone know if you can change it or should I just start a new membership?Theres my first stupid question :hammerhead:

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Posted

Opps maybe I got the name wrong it was dholly that pointed me to this site from the kitfox forum,was getting some pretty negative replies over there when I mention Subaru Avid. The Avid I picked up was from Ivan Christenson in B.C. Canada, He said it was one of the original first five Avid plus they made. I got my nick name screwed up it is supposed to be Marshawk, does anyone know if you can change it or should I just start a new membership?Theres my first stupid question hammerhead.gif

Willis you got the right DOUG. I was just pulling his short ones a bit.stirthepot.gif Russ.

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Posted

Opps maybe I got the name wrong it was dholly that pointed me to this site from the kitfox forum,was getting some pretty negative replies over there when I mention Subaru Avid. The Avid I picked up was from Ivan Christenson in B.C. Canada, He said it was one of the original first five Avid plus they made. I got my nick name screwed up it is supposed to be Marshawk, does anyone know if you can change it or should I just start a new membership?Theres my first stupid question hammerhead.gif

I will take care of that name for ya! Yer lucky I dont come up with something clever on my own hahahaha.

Welcome aboard! I think Suberavid (randy) AKJack (jack) and Dholly can help you out quite a bit! they all have the same run of "kits" as you I think and can help with alot of the "gotchas" that they have had to deal with and solve.

:BC:

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Posted

Thanks Akflyer,I guess I owe you some good Canadian beer Aye!I seen Randy's Avid and if I get mine looking half that good I'll be pleased.I was trying to print off a few of his pictures for referencing but doesn't seem to allow me to do.Is it possible somehow?

Thanks

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Posted

Thanks Akflyer,I guess I owe you some good Canadian beer Aye!I seen Randy's Avid and if I get mine looking half that good I'll be pleased.I was trying to print off a few of his pictures for referencing but doesn't seem to allow me to do.Is it possible somehow?

Thanks

Let me do some digging. I just tried to save the pictures and it will let me save a thumbnail print, but not the full size pic. I will see if there is some setting I can change to allow you to save or print the pics. Must be something with the new forum software because I used to save pics all the time by just right clicking and doing a save as.. Will let ya know what I come up with!

As far as the beer.... Hell yeah! One day I will take ya up on that one!

:BC:

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Posted

Heres a few questions

1.Are the shock cord length for the Avid + about the same length as Avid C ,the old was was close to 9' so I'm guessing the new on roughly 8'? I read somewere 7-8 wraps is this correct ?

2.Next I need a cowling,the old ones is pretty butchard,I tryed phoning and emailing Brett at Airdale a few days ago but got no answer yet, I heard he is a one man show and very busy so I'm sure he'll get back to me when he can. I like the cowling Randy has just wondering if thats were he got it?

3. I also need to build or buy a fire wall,probably can build one if anyone has a template for the Avid + Subaru I could buy off them. Thats about it for now .

Thanks, Frozen nose bastard :brownnoser:

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Posted

Hi Willis,

Welcome aboard! It is great to have another Fat Bastard Avid in the group! Hopefully we can be of some help to you in the building process. I know that Jack and Doug have been a great help to me on my specific Avid + questions and Leni and the rest of the guys are a super resource and kick in the pants. birthdayfriends.gif

1. On the bungies; I used the same bungees and wraps as the Avid MK IV and it was way two week so I added a second bunge to each side with half the length and half thewraps. That boosted the stiffness to what it needed (another reason they are called Fat Avids). You could do this with one bungee at 1 1/2 times the length but I already had the first ones installed.

2. I got my cowling from Airdale and did some extensive modification to it. I had to cut out the bottom of the cowl at the bottom corners of the firewall to get it to fit, then fill it back in. I then cut it around the firewall and boot cowled it and fiberglassed the halves together behind the firewall. Finally since I installed dual nose radiators I chopped big hoes in the front of the cowl and totally reshaped the front openings. There is a composoits shop up here that will make me a carbon fiber cowling off of my cowl; I don't know the cost yet but I am sure it would greatly reduce the per copy cost for every additional copy (any body interested?). I think it would easily shave half the weight of the cowl because with all that fiberglass work it added a lot more weight to the cowl than I would have liked.

3. For my firewall I used stainless sheet I got from an HVAC shop and was actually able to find some scrap that was large enough. I don't remember the exact gage but think it was around .024. Use the same thickness you would use if galvanized steel. I made a pattern out of cardboard slightly smaller than tt neede to be, stuffed bolts through it at the engine mount points, then attached the cowling. I then cut pieces of heavy paper to fit the exact curve of the cowling and taped them in place around the perimeter of the firewall for a pattern. Then bent .024 aluminum into an angle; 3 pieces about 1.5 x 1.5 by 30", enough so 3 pieces fit around the firewall with the angle legs facing forward and down. Use a crimping tool to shape it around the curve on the forward leg and cut wedges out of the down leg and fit it up to the cowl. Use clecos to hold it in place in a few places until you have it all fit. Then rivet it in place. The 1.5" forward leg gives you room for the screw nut plates to attach the boot portion of he cowl and the camloc recivers for he front cowl.

4. A couple of things Jack and I discoverd since we were fitting existing Avid wings, the front carry through tube was not spaced correctly and we had to heat and bend the pin ends of the tube forward slightly to fit the spar spacing of the Avid wing. I attached a couple of photos. I welded in a couple of gussets to add strength back just in case. If you are building new wings you can just build the wings to fit the fusalage.

5. Another thing we discovered is the push/pull cables for the flaperons have to cross and go to the oposite side flaperon to function correctly. The flaperon horns have to be extended about 1" longer to fit inside the fusalage (I built new ones).

6. The flap travel is extremely short as originally designed and I just finished modifying mine to work well. I built a new shorter link to get more travel and fabricated a push botton flap detent per Doug's design that works great now.

This is probably a bunch of jiberish until you get into the build then it will make sense. How much has been completed on yours so far?

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Posted

Hi Randy,thanks for all the info,its greatly appreciated.My Avid has the covering on it but I think I'll be do a little back tracking after reading some of the snags you guys ran into. My wings are off a heavy hauler c so I'll probably have the same problem with lining up the wings. Also the flight control column has not been lengthen so co-pilot needs to cut off left leg to sit in that side. I'll work on lengthing it. The original owner wasn't planning on bungees said the tires had enough cushion in them and he didn't need them. He must be way better at landing than me ,ill be slapping on some extra bungee.I'll try and get some pictures posted here soon if it stops raining and I can figure out how to post them and maybe you guys can pick out any other problems I might run into.

On the cowl I diffenently need one, my set up is a bit different since the radiator sits under the cabin area but if you think it would fit close let me know what he would charge

Thanks again

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Posted

Hi Willis,

If you have to bend your carry through tubes: I built a jig off of my Avid fusalage by taking long 3/8 bolts , dropping them into the pin bolt sleeves in the carrythrough tubes with a stack of washers on them to raise the heads until I could lay a piece of 1" square tube across the heads and weld them to it. You shoud be able to do something similar with the wings if you don't have the original fusalage. I then took a piece of pipe that would fit over the front carrythrough and slotted it to fit the bolt sleves. By just heating it to red and using the pipe to bend it I was able to tweak it until the jig would slide down into the pin sleves and my wings fit without tearing them apart and reworking them.

I am like you, I nail a perfect landing about 25% of the time; the rest of the time I need bungees. I blame it on the windlmao.gif .

If I remember right I added 5.5" to the inner and outter control column tubes to get the sticks centered in front of he seats. Both Jack an I had to move the tabs for the passenger end nut plates. I welded mine in but Jack built a saddle for the tube and epoxied it in. The rudder pedal tubes are OK as is since they can be spaced any width you need.

Jack mounted a belly radiator on his so he didn't have to go through as much rework on the cowl as I did. The Airdale cowl from Brett is probably the cheapest way to go but you will have to do some cutting and fitting. I will try to get a price estimate for the carbon fiber cowl but I am kind of afraid to ask at the same time.

Looking forward to your pictures!

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Posted

Welcome Willis :welcome:

Happy to see you decided to take on the Fat Avid project! I'm looking forward to some plane pics and following along on your progress. I think your cowl will be dictated first and foremost by whether you use the Sube, then by your choice of enclosed or belly radiator. As for the easiest to fit, the Airdale cowl will require the least work with the Sube, but I'm not a fan of the round intake look personally. There is also a Sube cowl option for the Kitfox 5 and 6 that is the proper width, and has a very close windshield curve and rake to what you'll need. However, I dunno how the thrust line would work based on the differences between the KF and Avid Sube engine mounts. My paper napkin calculations show that a KF 5 or 6 smooth cowl for 912 will work very nicely with the Avid 912 ring mount and thrust line on the Avid Plus fuse, and that the molded belly air scoop will not interfere with my float gear, so that is where I'm headed

Git 'r done! :beerchug:

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Posted

Willis you got the right DOUG. I was just pulling his short ones a bit.stirthepot.gif Russ.

Hey there Bubba, no touching the beard! :BC:

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Posted (edited)

Thanks for the info Doug, I will probably stay with the Sube since it only has 200 hrs and its my cheapest option, I may have a line on a used 912 Rotax but I'm not holding my breath on that one. Is there a big difference in the Sube cowl and the Rotax. I'll maybe check into the Kitfox cowl, I think I'm headed to the Arlington airshow this year so maybe see a kitfox 5 or 6 there. Is the Avid plus cowl similar to a Avid flyer heavy hauler C cowl in looks?

Got a chance to unfold the wings today for the first time dreading the worst but it looks like for some reason the carry threw tubes are pretty close to lining up.The holes don't quite line up but I'm hoping I can rivet coller on there and re-drill them? I'll have to have a closer look when one of my buddy's drop by.

Got a few pics but haven't figure out how to downsize them yet.

Later guys

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Edited by Marshawk

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Posted

Willis,

Since I have the entire Avid Plus kit and built new wings, I didn't have the retrofit issues you Fat Avid fuse up-graders had with spar pin alignment. FWIW, if it's close, I'd be tempted to make new spar doublers and Hysol and rivet them in using the existing rivet holes. Then make up a spar pin hole alignment tool and drill the new doublers to match your pin bushings. Russ was kind enough to drop his off when I drilled mine and it worked perfectly (see the thread here on "Setting wings to fuselage"). I think this is advisable in any event, because you really want to make sure the sweep, dihedral and twist are spot on.

Re: the cowls... the Avid Plus and Airdale cowls are different, as are the Avid C and Mk-IV cowls. The Avid Plus cowl looks very similar to the Avid Mk-IV cowl, in fact, it was the basis as explained to me by Steve Winder in an email some time ago:

Hi Doug,

The Avid+ Cowling was based on the MkIV cowling. We took an old preinstalled MkIV cowling which already had the camlocs in place. Attached the bottom to the Avid+, cut wedge/slot in the top to get it to "open out" due to extra width. Then using the existing camlocs attached the two halves togther on the AVid+. Because the Avid + has re-raked windshield we cut the windshield flange off the old cowling and grafted up to the Avid= New Windhshield, filled in all the gaps, made up a plug and then pulled a new Avid+ MkIV cowling. See pictures on Vince Nartkers Avid+ flying with a 912S.

I've attached a pic Vince sent me of his Avid Plus so you can see. One thing to keep in mind is that cowl was on a 912 powered plane and might be too narrow for the wider Sube. Also, the pic of the green and white Airdale Flyer on the Co.'s website shows rectangular air inlets, however, pics of cowls of a couple Airdale Flyers I've found on the internet show round inlets. Maybe one was for Sube and the other Rotax? Best check with Brett about the version(s) he currently produces if interested.

With regard to the model 5-6 cowls available from Kitfox, there are both 'smooth' and 'round' cowl versions specifically for Sube, Cont, Lyc and Rotax. While the width is approx. the same as our Avid Plus fuse, they vary in length, width, thrust line and windshield curve/rake to accommodate the different engine widths and engine mount scenarios. Again, depending on the different engine mount (Sube vs. Rotax) and fuselage (Avid vs. Kitfox) combination, those are at least a few choices for you to check out. They might not be a direct bolt-on like the Mk-IV based Avid Plus cowl (dated-looking, IMHO), but they do offer something different with the least mount of fitting fabrication required. Personally, as mentioned earlier, I prefer the KF 5-6 smooth cowl for 912. Just seems to look the most aerodynamic and up-to-date, plus it actually tapers lower at the nose for better forward visibility in flight and on the ground. After looking around the nose of my KF 3, this is important to me on my Avid Plus TD.

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Posted

Got a few pics but haven't figure out how to downsize them yet.

Nice pics, looks like a lot has been done. You can right-click on a photo in your Picture Album and see if it opens a short cut menu that gives a reduce size option there. It will add a smaller size copy to your album that you can attach to your post here and leave the original intact. 800x600 Medium size for landscape photos works good.

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Posted

Willis & Doug,

A word of caution, I decided to replace the steel doublers on my wings when the holes wouldn't line up, the problem was that when I attempted to gain access to the rivets on the aft side of the spar I actually had to cut into the tank to see them. If you want to insert the new style roto-molded tanks, no big deal, but if your tanks are solid, I'd really give consideration to the method Randy described. Just be sure before starting, that you really examine closely where the rivet heads are located. Another thing that needs to be considered is, can you pick up the existing rivet holes if you decide to drill out the old doublers and move them to give you the alignment you're after? Most of mine were close, but on some I ended up drilling out to 3/16" rivets to prevent having wallowed out holes. Also, when heating your carry-through, make sure you don't exceed 1100deg.F, beyond that 4130 looses its strength. The welder that did mine had a temp stick that told him when he was close to the critical temperature.

Good luck,

Jack

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Posted

Hi Jack,

I will let you and Randy help with the spar pins, unfortunately I keep forgetting exactly what issues you guys ran into. I do wonder if Willis doesn't already have plastic tanks? I noticed his caps and they certainly aren't the oem, but they don't look like the wingtanks.com or the Rocky Mountain Wings caps either. Wonder what's under the skin?

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Posted

Thanks Doug and Jack for all the info, it really helps when looking at all the options.We managed to unfold the wings today after a friend dropped by and found the front hole on the pilot side wing actually lines up and would be able to put the bolt threw. The passenger side not so lucky its probably about a 1/4" from lining up. We didn't do any measurements but by eye they looked to be straight across from each other. I have a laser that maybe I can rig up to check accurately.

Doug I hear ya on looking over the nose of your kitfox ,I fly a kitfox 11 with big nose too, I just hope a deer doesn't decide to cross my path someday once the tail drops down on it.

Does anyone happen to have a picture of there bungee cord landing gear wraps for there Avid . I just put new ones on the kitfox and it was pretty simple but the Avid seems to start and end in the same area and not a lot of room for all the wraps needed.I'm not sure if the previous owner made the hole in the fabric big enough since he wasn't planning on using bungees.

:beerchug:

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Posted

Willis-

I spoke w/ Brett last night and asked him to check on the Airdale Flyer cowl fitment for us. He did receive your email but has been out of town for the past week and is just catching up on orders and email.

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Posted (edited)

Thanks for checking up on that Doug, have you put on your bungee cords yet? Hey just read your parts list from your KF3 and pretty sure I bought your covers off you for my kitfox 2 ,small world :BC:

Willis

Edited by Marshawk

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Posted

Thanks for checking up on that Doug, have you put on your bungee cords yet? Hey just read your parts list from your KF3 and pretty sure I bought your covers off you for my kitfox 2 ,small world :BC:

Willis

No bungees yet, just some pretty red zip ties. And you are correct about the covers, hope they're working out for ya! :beerchug:

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Posted

Willis,

another thing to consider when working on your cowling is the clearance over the top of the belt drive. When you tilt the cowl enough to clear it the attach points could change causing some unplanned fiberglass work. I ended up tilting mine up in the front to clear, but because I had booted the cowl, it only caused me to do some trimming at the back. This was on top of the work I caused when I decided not to use the 582 Rotax for power. The Subaru points to the right, where the Rotax points to the left, if I have that right. Anyway, booting the cowl allowed me to make the adjustment at the firewall without too much hair pulling. A few more considerations for you. If you do decide to go to Arlington this year let me know. I plan on being there and maybe we can meet and discuss our projects.

Jack

Since I have the entire Avid Plus kit and built new wings, I didn't have the retrofit issues you Fat Avid fuse up-graders had with spar pin alignment. FWIW, if it's close, I'd be tempted to make new spar doublers and Hysol and rivet them in using the existing rivet holes. Then make up a spar pin hole alignment tool and drill the new doublers to match your pin bushings. Russ was kind enough to drop his off when I drilled mine and it worked perfectly (see the thread here on "Setting wings to fuselage"). I think this is advisable in any event, because you really want to make sure the sweep, dihedral and twist are spot on.

Re: the cowls... the Avid Plus and Airdale cowls are different, as are the Avid C and Mk-IV cowls. The Avid Plus cowl looks very similar to the Avid Mk-IV cowl, in fact, it was the basis as explained to me by Steve Winder in an email some time ago:

I've attached a pic Vince sent me of his Avid Plus so you can see. One thing to keep in mind is that cowl was on a 912 powered plane and might be too narrow for the wider Sube. Also, the pic of the green and white Airdale Flyer on the Co.'s website shows rectangular air inlets, however, pics of cowls of a couple Airdale Flyers I've found on the internet show round inlets. Maybe one was for Sube and the other Rotax? Best check with Brett about the version(s) he currently produces if interested.

With regard to the model 5-6 cowls available from Kitfox, there are both 'smooth' and 'round' cowl versions specifically for Sube, Cont, Lyc and Rotax. While the width is approx. the same as our Avid Plus fuse, they vary in length, width, thrust line and windshield curve/rake to accommodate the different engine widths and engine mount scenarios. Again, depending on the different engine mount (Sube vs. Rotax) and fuselage (Avid vs. Kitfox) combination, those are at least a few choices for you to check out. They might not be a direct bolt-on like the Mk-IV based Avid Plus cowl (dated-looking, IMHO), but they do offer something different with the least mount of fitting fabrication required. Personally, as mentioned earlier, I prefer the KF 5-6 smooth cowl for 912. Just seems to look the most aerodynamic and up-to-date, plus it actually tapers lower at the nose for better forward visibility in flight and on the ground. After looking around the nose of my KF 3, this is important to me on my Avid Plus TD.

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Posted

Willis,

I added a few comments on the cowling, but placed it above the conversation. Might be some helpful info for you.

Jack

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