Mark, for the threaded holes in the tube at the bottom on the panel you might want to consider injecting some hysol or epoxy into the pilot holes and trying to fill the tube. It will give your threads more purchase into the tube. Most of that tube is only 0.035 wall at best and you won't get many threads through that and would be very easy to strip after only one or two removals. From what I can see that tube is part of a larger weldment and wouldn't be easy to remove to flood it with epoxy. I think for the extra effort and longevity of the installation it would be worth the few ounces of added weight.
Would installation of "Rivnuts" be a good choice as well or is the wall to thin ? ... perhaps Rivnuts installed into the tube with epoxy plugs* already put in place. THINKING ALOUD : * you'd have to make another tube (thin walled to reduce weight) of smaller diameter and create compartments where you wanted the epoxy to fill a void. That smaller tube would then have to be inserted into the larger diameter one (tight fit) but that means replacing the tube already supplied with the frame (A Mike Patey type operation) ... too much ... LOL
Don’t even go there, would compromise the tube too much. 0.035 isn’t enough to support that at all. Never have liked rivnuts and they don’t set well into 4130. Been in the industry since 79, don’t even want to begin counting the rivnuts I have had to try and drill out and replace. Drilling out large enough for a rivnut would weaken the tube way too much and I don’t think that the tube has enough depth to accept a rivnut for the required screw. That tube is a lateral brace for the entire fuse in that area. Don’t know the kit well, but I know Chris H would have agreed that flooding that tube with Epoxy would be a better solution. Maybe drill a small vent hole in the top of the tube in the middle, create injection holes on each end and pipe some slow set “thin” epoxy or hysol in from both ends, your looking at 4-5 ounces of extra weight at best and you end up with a very ridged “composite” tube that will hold a thread for the screws. If the SC ever goes onto floats and I hope it does that lateral bracing would be a very welcome addition.@@daverobinsonTnT
Yes indeed, Rivnuts can be a pain, I work for several OEMs and the shop floor used to hate it when we called up Rivnuts in tubing. However modern offerings are much easier to work with thanks to the tooling supplied. Dissimilar materials issues are also much better addressed with the modern options. Note I did mention the need to insert a smaller diameter tube into the larger one and also filling compartments within that smaller tube with epoxy. This would provide much more surface area to contact with the Rivnut, as each compartment is to be of sufficient size to accommodate installation of the Rivnut at each fastener location where it would be filled with epoxy, The overall weight increase would be very low (the inner tube having a very thin wall to keep its weight down). The huge downside would however be to have to cut out the existing tube segment and weld in place the new tube assembly. Expensive and time consuming but then again, Mark is a perfectionist.
One alternative that Zenith Aircraft uses on the same size tubing (to mount the sides of the windshield) is to use self-tapping screws with a little Loctite on them. It allows for a smaller hole than a threaded fastener or rivnut. I've never had one come loose yet! I suppose one could use the "weak" Loctite formula that is used for instrument screws, etc., and one could then be able to remove the screws, if necessary, without resorting to heat that is often necessary to soften the stronger Loctite formulas.
I very much admire your technique, in that you 'trial fit' things first and then remove them to work on them on the bench (two thumbs up). I'd just like to point out that instrument cases are not primary structure, so some sort of structure should support heavier instruments. One should not rely on the instrument's case to provide stiffness for the panel, the panel should be stiff enough to support the instrument without deflecting. Excellent video as always. Thank you for taking time to make it and for sharing it with the experimental & light sport aircraft building aviation community
The nibbler, my go to tool for cutting out blind holes. Bought a HF one for reskinning the chin turret of a B-17 figuring to purchase a better one later. HF lasted all 7 years I worked on the B-17. Thanks for the frequent updates. We don't need to see every minute detail. Now instead of music just put in the sound of a Wright 1820 at idle.
Hey Mark... had some questions from the last panel video, you answered all of them except for the final finish. I imagine you'll try to stay period correct? Oh yeah, I do believe that I spotted the cleco containers that I'm sure I won a few months back! Must have been an oversight! Thanks again and Blue Skies brotherman!
The custom-cut panel is really nice! I'm sure this is an expensive process, especially considering the trial cut template, etc. Likely the expense varies with the complexity of the panel, but could you give us at least a ballpark estimate of cost?
Great video! I've been planning the same build for my panel - except I was going for a three parts panel for easy future upgrades. Question, how are you planning to secure the new panel on the old? I was planning on using rivnuts and put some cork tape in between to prevent vibration etc. Thoughts? Thanks!
I'm curious about flap controls on the right side. You added a throttle, dual brakes, but nothing for the flaps. Just curious if you were planning on training how that would work.
Tangential question since you’re discussing nut plates and attaching things: How did you secure your wing root fiberglass fairings to the wing skins? Nut plates with blind rivets?
@@KitplaneEnthusiast just straight to the skin? I was worried that wouldn’t be resilient enough and too susceptible to stripping. Thanks for the feedback! About to finish my cruzer’s right wing. 😎
