E714 Elevator Counterweight...

Can someone give me some guidance into how to cut (what tool?) the E714 elevator counterweights? Is this something that needs to be done during initial elevator assembly or can it wait until later, say when I am attaching the elevators?

Thanks

NTM

Depending on what you are building you may not want to cut the counterweights at all. I am building an RV8 with electric elevator trim and i will need to add weight to the uncut weights to balance 100% with paint. I think with manual trim there would have been plenty of weight for me. If you do decide to cut them i would think a coarse toothed handsaw would work well. A hacksaw should work, but will be slow going because the teeth will plug up more. Tony

If your talking about installing them between you c-balance skin and your outboard ribs; then you need to file a bunch of material off the corners before they will fit.

Oh, if you have a bench grinder with an SB wheel, you can take it outside, close your garage door, put on a paint mask and grind away. blow yourself off real well with an airhose before going back inside. This is not advised if you have kids that play in your yard. Unless of course they are the neighbors annoying kids that you really don't like.

As mentioned, first get them fit to the elevator. I also had to shave and round the forward side to get it to fit. Us a corse vixen file with the bolube stick for lube. The side with the electric trim is not cut, you may have to add weight later. The other side I cut with a very course hand saw (a fine blade hacksaw will just load up) and filed to final shape with a file. I went with Van's mininim amount of material removal...It seems like it will work fine. I would rather start heavy and remove more at a later time.

I'm assuming you're speaking about the right one. I cut mine in the bandsaw and removed the minimum amout required.

However, I never installed it. I got thinking how of I'd be able to remove it if I rivetted the assembly in place. Even without the bolts going through to hold the lead, mine is not going anywhere. I thought removing some material in order to make the lead removable, but that doesn't seem like a good idea as I don't want it to ever move. Still scratching my head on this part over what will probably be nothing.

Edit: I kept the lead in case I need more weight on some other conterweight down the road.

Just got to this point and was scratching my head wondering what Vans wanted us to do with the lead weight if it didnt fit correctly to cleco everything up. So if I am understanding you guys correctly, I should use a vixon file to file just enough lead of to be able to fit in there correctly?

Probably use a mask and goggle and do it outside of garage I assume as well!

Thanks

I only removed the leading edge area for a round edge contour for glassing and blending, after paint, I only needed to remove a couple Oz to balnace the assembly.

pilotian said:

Just got to this point and was scratching my head wondering what Vans wanted us to do with the lead weight if it didnt fit correctly to cleco everything up. So if I am understanding you guys correctly, I should use a vixon file to file just enough lead of to be able to fit in there correctly?

Probably use a mask and goggle and do it outside of garage I assume as well!

Thanks

Click to expand...

I didn't need to remove any material to get it to fit. I did have lots of trouble drilling it for the bolts, I destroyed a couple of pieces and ended up ordering new ones. Here is how I drilled the lead weight the second time around.

I ASSume-d that Vans knows what they are talking about and trimmed the right elevator counterweight per plans. I plan to fly before painting, so hopefully things will work out. If I need more weight, I'll bolt some washers to the rib as others have done.

To trim the counterweight I first drilled a hole vertically to get the plans-specified radius. I clampled the weight to my drill press VERY securely, set the lowest speed (~200 rpm), then started with a #40 hole and worked my up slowly. Then I cut lengthwise with my bandsaw (very coarse blade) and lots of boelube. I did have the blade get stuck a few times, and had it jump the wheel once, but I got through it. Note the cutout piece on the vise. The divot in the cut surface is a manufacturing defect.


I cleaned it up with vixen and round files and called it good:

trimming counterweight



Here's another way to trim the lead counterweight for the right side elevator for those of you who are finding it hard to cut with a hacksaw or band saw.

I used an old router bit chucked in my drill press, turning as slowly as the drill press would allow. I set the depth adjustment on the drill press to match the dimension shown on the plans, and made multiple cuts, re-positioning the counterweight each time, until the whole forward end of the counterweight was cut.

With the counterweight securely clamped down, the router bit milled the lead away nicely. Used plenty of oil to lubricate it and it worked like a charm.

Well I installed mine per Vans and I am not sure just yet, but I think I will actually have to add some weight. I am painting right now and suspect that they will not balance. I am concerned as to how to do this on a finished elevator.

Bird

Sheet rocktools

I used a sheet rock keyhole saw and sheet rock file. Nothing clogs up!