kens_cockpit
Well Known Member
Task - run a battery cable from the back of the plane to the front. I thought I could do this but I'm running into interference problems around the wing spar box.
I have drilled the holes in the location identified in OP11. This causes areas of possible interference.
The first problem is possible interference with the aileron pushrod. See the attached pictures. I've put a piece of straight fuel tube to represent where the aileron pushrod would be if it was actually rubbing on the holes in which it runs. Of course that won't happen but I want to keep as much clearance from that position as possible.
On the aft side, even keeping the cable as low as possible, it looks like it will come very close to the aileron pushrod when I install it. Highly undesirable I expect. I could put some silicon down and glue the battery cable to the floor to hold it down but I don't know whether that would be strong enough. Perhaps I could get a P-clamp and attach it to F814A-L close to the aileron pushrod hole to hold the cable close to the floor there. But it will be difficult to get the cable back up to the hole in the spar web then.
I have looked again at drawings 25 and 31 and they show the cable travelling further inboard and higher than the holes shown on OP11 suggest. If I run the cable along the top of F814A-L and then bring it back down to the OP11 hole location it will run directly through the space where the aileron pushrod will run.
Has anyone else found this problem and if so, how have you solved it?
The next problem is interference with the rudder cable on the forward side of the spar box. Bringing the battery cable up to where the P-Clamp is shown attached to the F-878PP -L mid cabin brace on drawing 31 means the rudder cable will rub on the battery cable. Once again undesirable. See the attached picture. The rudder cable is not actually hooked up to the idler bar for the rear rudder pedals. it is haning down in this picture but even when hooked up it will rub on the battery cable.
I could just put some tube over the rudder cable and possibly tie that to the battery cable to prevent friction between the two. Or once I have installed the fuel lines around the fuel selector valve I could move the battery cable more outboard, attaching the P-clamp with a piece of angle at an appropriate place, perhaps on the F883A Fuel valve bracket.
Has anyone encountered this before and how did you fix it?
Thanks for your help.
BTW, will there ever be a simple job that can be completed without having to solve other problems? I've been doing this for three years so far and the moment I think, "I'll just do [insert the simple looking task]," I am bound to be in for a depressing bout of creating problem then solution then problem caused by the solution, seemingly forever! I'll get there in the end I suppose but man I find it frustrating. I try to think carefully about things before I drill any holes but I still find I don't think of everything even when I think I must have!
I just want to fly but I don't want to carelessly rush either. I reckon I've got another 3 years or so before I can do that. What a character developing project this is!
Ken Stanton
RV8QB
I have drilled the holes in the location identified in OP11. This causes areas of possible interference.
The first problem is possible interference with the aileron pushrod. See the attached pictures. I've put a piece of straight fuel tube to represent where the aileron pushrod would be if it was actually rubbing on the holes in which it runs. Of course that won't happen but I want to keep as much clearance from that position as possible.
On the aft side, even keeping the cable as low as possible, it looks like it will come very close to the aileron pushrod when I install it. Highly undesirable I expect. I could put some silicon down and glue the battery cable to the floor to hold it down but I don't know whether that would be strong enough. Perhaps I could get a P-clamp and attach it to F814A-L close to the aileron pushrod hole to hold the cable close to the floor there. But it will be difficult to get the cable back up to the hole in the spar web then.
I have looked again at drawings 25 and 31 and they show the cable travelling further inboard and higher than the holes shown on OP11 suggest. If I run the cable along the top of F814A-L and then bring it back down to the OP11 hole location it will run directly through the space where the aileron pushrod will run.
Has anyone else found this problem and if so, how have you solved it?
The next problem is interference with the rudder cable on the forward side of the spar box. Bringing the battery cable up to where the P-Clamp is shown attached to the F-878PP -L mid cabin brace on drawing 31 means the rudder cable will rub on the battery cable. Once again undesirable. See the attached picture. The rudder cable is not actually hooked up to the idler bar for the rear rudder pedals. it is haning down in this picture but even when hooked up it will rub on the battery cable.
I could just put some tube over the rudder cable and possibly tie that to the battery cable to prevent friction between the two. Or once I have installed the fuel lines around the fuel selector valve I could move the battery cable more outboard, attaching the P-clamp with a piece of angle at an appropriate place, perhaps on the F883A Fuel valve bracket.
Has anyone encountered this before and how did you fix it?
Thanks for your help.
BTW, will there ever be a simple job that can be completed without having to solve other problems? I've been doing this for three years so far and the moment I think, "I'll just do [insert the simple looking task]," I am bound to be in for a depressing bout of creating problem then solution then problem caused by the solution, seemingly forever! I'll get there in the end I suppose but man I find it frustrating. I try to think carefully about things before I drill any holes but I still find I don't think of everything even when I think I must have!
I just want to fly but I don't want to carelessly rush either. I reckon I've got another 3 years or so before I can do that. What a character developing project this is!
Ken Stanton
RV8QB