RV-3: Throttle Quadrant Control Cables

[Ironflight]

I must admit, one of the things that I have not been looking forward to on the RV-3 project has been installing the engine control cables at the quadrant end. This is mostly because of how tough the job proved to be on the RV-8 back when I built the Valkyrie ? there isn?t enough room, penetrating the gear towers was a pain, and the quadrant mount was sandwiched in an awkward place. I figured that with the tiny RV-3, things would be even worse. But low and behold, I was able to take a look at our ?stalking horse?, another local RV-3 project that is being helped along by an experienced F-1 builder (ok, he is THE F-1 builder?), and I noticed that instead of using the bulky cables with large mounting nuts on each end, he used the Aircraft Spruce A-920 series cables ? much more compact, and easily fit in the close confines of the -3. To secure the ends of the outer casings, they use a notch/slot arrangement which necessitates building a special bracket, but this proved amazingly simple with some extra angle and a little fabrication. The pictures below are fairly self-explanatory. The lack of bulk in the cables allows them to be placed as close together as the levers in the DJM quadrant, so everything comes out parallel ? very nice!

Cables installed on the quadrant ? it is easier to put the ends on the quadrant levers, then attach the cables.

Fabricate the cable support with some angel, drill three holes, then band-saw the slots to the holes.

I used a pair of AN3 bolts to attach the cable support ?comb? to the F-303 forward bulkhead ? very sturdy!

Overall, I am pressed with the smooth operation of these cables, as well as their ease of installation. Oh, and they don?t come with a label that says ?Not for use on aircraft??.

Paul

 

[rvator51]

Looks great Paul! Do you have to build the same type of bracket for the other end of the cable on the engine side?

 

[Ironflight]

Looks great Paul! Do you have to build the same type of bracket for the other end of the cable on the engine side?

Well, I haven't gotten to that end yet....but ACS does sell some pre-made retainers for that type of end - I might be able to duplictae them.

 

[Mike S]

Are you planning on using some kind of retainer over the open "U" slots, to keep the cable housings where they belong??

 

[David Paule]

It looks like the slot in the frame just aft of them might be a sufficient retainer. That is, it looks like the cables can't pop out of the slots.

If in fact they can, some safety wire will fix that.

Dave

 

[Ironflight]

It looks like the slot in the frame just aft of them might be a sufficient retainer. That is, it looks like the cables can't pop out of the slots.

If in fact they can, some safety wire will fix that.

Dave

Exactly - there is no way they can physically get out of the slots due to the bulkhead hole, but as I move them around, if I think they might get loose, I'll just use some safety wire. The slots are tight enough that they almost "snap" into position.

Paul

 

[johnbrooker]

Battery placement in RV3

My RV3 has been out of the jig about a week,put in baggage skin,seat skin and working on platenuts and skins around stick.I was wondering about placement othe battery(PC 680).The 3 will have a 0320 with a wooden prop built as light as I can build it.I saw pictures of Tony's battery in front of the spar.I have built a 6 and a 8 but don't have clue about CG on a 3.Oh I forgot to say I weigh a buck eighty.Thanks

 

[F1Boss]

engine side retainers

Well, I haven't gotten to that end yet....but ACS does sell some pre-made retainers for that type of end - I might be able to duplictae them.

Jegs Racing has some clip-type retainers -- I have used those along with the slot style doo-hickeys with good luck. You can google 'morse cable retainers' and come up with other vendors too. This ain't Rocket science!

http://www.jegs.com/i/CSR/170/60017/10002/-1?parentProductId=745775

BTW a loop or two of .040 safety wire will keep the cables in the slots at the bulkhead connection, tho more complicated methods will also work. K.I.S.S. rules!

Carry on!
Mark

 

[Ironflight]

My RV3 has been out of the jig about a week,put in baggage skin,seat skin and working on platenuts and skins around stick.I was wondering about placement othe battery(PC 680).The 3 will have a 0320 with a wooden prop built as light as I can build it.I saw pictures of Tony's battery in front of the spar.I have built a 6 and a 8 but don't have clue about CG on a 3.Oh I forgot to say I weigh a buck eighty.Thanks

We're going with the WW 151H, with is a very light constant speed. Fortunately, we have Randy Lervold's example as a model, and he found that he needed to put the Odyssey behind the seat, so that is what we're going to do as a first cut. The 430W is our only "heavy" piece of avionics, and it is a little forward of the spar, so I am pretty sure the aft battery is what we'll need.

Jegs Racing has some clip-type retainers -- I have used those along with the slot style doo-hickeys with good luck. You can google 'morse cable retainers' and come up with other vendors too. This ain't Rocket science!

http://www.jegs.com/i/CSR/170/60017/10002/-1?parentProductId=745775

BTW a loop or two of .040 safety wire will keep the cables in the slots at the bulkhead connection, tho more complicated methods will also work. K.I.S.S. rules!

Carry on!
Mark

Great Boss! I bought a few of those same things from ACS for about the same price - we'll see how they work FWF....and I agree on the safety wire - nice and simple.

 

[RV-4]

Power Quadrant

Hi Paul
Can you share with us where you purchased your power quadrant.I really like the look of it..

Thanks

Bruno

 

[Ironflight]

Hi Paul
Can you share with us where you purchased your power quadrant.I really like the look of it..

The throttle quadrant is from DJM - he calls it the "Danny King Special" - curved top and short levers. I added a Throttle grip from FatBoy Throttles to give a unique look. The mount plate and sheetmetal top is all custom for our RV-3 - I just doodled around with material I had on hand to make them. Both DJM and Fatboy are GREAT to work with, and advertise here on VAF.

Paul