RVUK Tips

Some words of explanation might be in order. The reservoir is mounted on the engine side of the firewall for easy checking of level and replenishment. The pink plastic pipes above the brake valve are taking the fluid to the master cylinders. The yellow spirwrap is around the alloy pipes going from the brake valve down to the brake callipers.

Click on photo to enlarge

Note the half flange on the cable bracket to make it more rigid. The end of the bowden cable is held in a pipe cushion clamp. The other end of the bowden cable emerges on our centre console, between the pilot's knees. The valve is free moving but those who don't know about this tend to pull on the brake knob as though it's the strength of their pull which is applying the brake, whereas all it's doing is trapping the pressure applied through the brake pedals.

Belt deflection is an unreliable method of tightening the belt.

Instead, use a torque wrench on the pulley belt and adjust the tension so that you get about 12 ft-lbs before the belt slips.

A loose belt can lead to under-voltage or over-voltage from the alternator. Over voltage is caused by the regulator trying to force more output from the alternator while the belt is slipping. When the belt grabs, it puts a surge of voltage on the bus.

Please don't ask me how I found out!

ref Lycoming s. i. 1129A

Lycoming SI 1129A Accessory Drive Belt Tension

New 3/8” 11-13 ft/lbs 132-156 in/lbs used 3/8” 7-9 ft/lbs 84-108 in/lbs

New ½” 13-15 ft/lbs 156-180 in/lbs used ½” 9-11 ft/lbs 108-132in/lbs

We find it much easier when doing a run of dimples or small rivets to limit the travel of the squeezer jaws. We've drilled out a bolt to fit the squeezer shaft, then drilled and tapped into the bolt to take a small screw to clamp it in place. We've lost the mark 1 version pictured here and now have the mark 2, a thinner bolt with a grubscrew in the side.

Another simple but effective idea. Rather than marking and cutting all those angles on your control surface stiffeners individually this simple jig lets you whip them all off in moments on a bandsaw. They even come out all the same length as the clecos fix the position of the angle piece that's being cut. I can't claim the jig give the incredible finish and rounded corners seen in the picture - that stiffener has already seen the Scotchbrite wheel!

1. If you don't have a dimple die for countersunk bolts, like those to mount the lead counterweights on the elevators, you can make one yourself by countersinking a hole of the correct diameter in a massive aluminium bar (or piece of hard wood). Place the bolt through the skin and the bar and hit it carefully on the head with a hammer. Put a tape on the bothhead to prevent damage. (see picture)

2. The best way to remove lead from the right elevator counterweight is with a sharp chisel and a hammer. Allmost any other method will be tedious and frustrating.

3. The easiest way to shape the rudder and elevator stiffeners is as follows: Mark the stock angle roughly to avoid mistakes (take your time in studying the plans), and cut the the angle in the individual pieces. To remove the tapered bit make a die from two pieces of aluminium bar (taped together on one long end like a taco shell) and place the part between the two halves of the die, with the cut-off bit in the die. Place in a workbench vise grip and cut about six times along the edge of the die on both sides, with a sharp knife. The part can then be broken off along a perfectly straight line with no deformation of the material. A belt sander is ideal to finish the part.

6. We primed the parts of the empannage by etching them in Alumiprep33 and alodining them in Alodine 1201. This gives enough corrosion protection without adding any weight (unlike primers). Don't buy the chemicals from Spruce but try to obtain them in your country (the transport cost are bizarre). Find a dealer via www.henkel.com (see picture)

We made a wooden frame 180cm long with plastic in it. Make a hole in the plastic afterwards and let the chemicals flow back in large jerrycans for re-use. Wear gloves and masks!

8. We had very good experiences with buying tools from the Yard www.yardstore.com . Good tools at good prices, extremely fast delivery (in the Netherlands), no fuzz.

RV BUILDERS TIPS