Badland Part 103 Pilots and Builders Forum

Re-positioning the Polini 303 Cooling System below the engine re-sized some of the system hoses. Many of the clamps provided did not fit. Finding Oetiker (ear clamps) is difficult and sizing is always a chore. I found a ClampTite tool (~$23 on E-bay) that creates clamps from safety wire. The tool arrived yesterday and I used it for the 1st time this moring to install the radiator fill/overflow reservoir and associated hoses.

I converted an automotive 2.75" exhaust system U-clamp by replacing the heavy steel (5/16") U section with a length of 3/16" aluminum rod that I bent into the 2.75" U and threaded both ends. I mounted this high up on the firewall and then routed the hoses.
The tool works well. I'll replace the 4 screw-type clamps I used earlier using the wire-wrap tool.

I've seen this tool several times. One big advantage is there are fewer times when a project gets delayed because of not having the right size hose clamp. Have tool and safety wire, no more problem. Better yet is having someone you know confirming the tool appears to do the job well. Thanks for posting.

Todd

The instructions that come with the tool are a little sketchy but luckily there's a good video on U-tube.

The instructions say that you can do single up to 10 wraps. 2 seems to be the best for our needs. Instructions also say to use a length of wire 15 times the diameter of the tubing plus another 12". That seems to be about right for the double wrap.

The tool comes with a small roll of fairly flexible wire ... looks to be about 0.04". The sample roll does about 3 clamps for 7/8" od hose. A similar size roll at Harbor Freight is $0.99. I think any smaller diameter would possibly cut into the hise.

The smaller wire would be a concern. I agree on the double wrap method. That certainly would lower the chance of leakage. I originally saw the tool on a YouTube video being sold at an air show. I like the screw clamp style, but getting the right size and most important, quality built clamps is difficult. I hate tightening down that type of clamp to have the screw start skipping, or I've had the screw completely fall out! That's not a clamp, it's a disaster if that were to happen in the air.

Todd

I agree with you both about the screw clamps. I tend to safety wire them through the screw slot and then around the other end of the protruding bolt.

In other instances, with smaller hoses, I'll jist safety wire them with two or three wraps. It worked well on my race bikes for years.

Today I finished replacing the 5 screw clamps with the Clamptite tool/wire. The knuckles on my left had are a little scratched up from the ends of the wire wrapped around the barrel of the tool. My advise is to clip them short. before you start to tighten the wingnut on the tool.

I also completed all the connections to the instruments on the panel except for the pressure tube connection for the multi-function gauge (A/S, VSI, and Alt}. I won't run that until I complete the port wing rigging. I have several straight and right-angle push on tubing connectors (1/4" id). I hope to use those in the wing root to ease wing-folding.

Epoxied the port-side plastic flaperon tip in place while the weather is warm ... mid 60's today and expecting 70 degrees tomorrow. Crazy North Texas weather. My el cheapo Harbor Freight hand-held cutoff tool went south yesterday .. overheats and shuts down with 5-10 seconds of use. Can't complain much as it served me well through 2 other projects. I'll probably go $39 for another. Need it to cutoff the excess flaperon spar tube and the lift strut tubes once my replacement inserts arrive.

Chris says he's contacted his USA Polini Rep about the prop nut. She asked for my engine serial number so I hope to get my replacement soon.

Will do some pictures tomorrow and update the build log.

I'd love to see your plastic flaperon tip, if you could post a picture of that.

You would likely know this better than I...is there any harm to using right angle fittings on your hoses for the ASI? I always wondered if it might affect the airflow through the tube and as a result give a false reading. I imagine it isn't really a problem with the other gauges, as they are more ambient pressure driven rather than forced air pressure driven like that ASI is (for want of a better description).

It's really difficult to see the nice shape of the tip because of the black material. If it was 3D printed they did a great job. Very light.

I need to cleanup the excess epoxy, but it really looks good.
I don't think there'd be much airflow/pressure reduction/interference with a right-angle connector at the fuselage/butt-rib junction. If I was still teaching I might have my IE students run a lab check. I may shoot off an email to one of the ME guys.

Nice instructional article on Pitot Systems. Diagrams show several with right angle connectors. SHould be OK.

Interesting on the flaperon ends. Peer and I have been working on the same thing. I've been dragging my feet though. He did a balsa wood model and shipped that to me. This is a droop end. I did some photgrammetry and pulled the image into my 3D printer editor to produce these:


They have been done for months. Other things have gotten in the way of sending them out to him for test fitting and adjustment. We also hope to produce a full wing droop end. Peer included both the droop and regular end, I again have been dragging on getting the regular end through the photgrammertry process and into the 3D printer editor.

There are so many things that can be created with the 3D printer. The pieces are lightweight and yet can add to the safety, comfort, and looks of the plane that it's time well spent getting to a final product.

Those look very similar to the ones I got from Chris. Mine appear to be slightly thinner.

I also have hi composite wing tips on order. They aren't done yet but he really just describes them as "tip plates". I included them on my original order as I did with the flaperon tips.

I've also settled on "quarrter-naked" Oratex. Chris says he'll be making an Oratex order in the next few weeks hopefully with enough builders we can get some sort of quantity discount.