Scale RCM 1/3 Scale Champ Build

[TonyHallo]

The manual doesn't suggest a specific length, just route to bottom of the plane.

Got the left side off the bench. Been thinking about the sharp break on the lower longeron, the plans indicate a butt joint with two 1/4" balsa gussets on each side. Simulated a bend once the side removed and of course as one might expect, the butt glue joint failed. I cut equally on each side of the butt joint and spliced a lap joint greater than 10 to 1. It is pinned back down while the glue is drying.
I use this tool made from scrap to mark the cut lines on the pieces filled in between the upper and lower longerons, hold the stock over the plan on top of the longerons at the desired angle, butt the tool against the longeron and give it a mark.

 

[Snoopy1]

Yes but joints suck just do not hold not even good enough to get it of the workbench.

 

[TonyHallo]

Bought a laser level when doing the bathroom last spring, can find so many uses for it. Here checking the vertical and horizontal centerlines are plumb when the firewall is fit into the fuselage sides. In the past this would be a "I hope it's right"

 

[TonyHallo]

Managed to get the fuselage formed up. Switched from coffee to Miller Lite, currently bending the front longerons with paper towel soaked with ammonia using a bungee cord to pull them together. The plywood is clamped in place to keep the cabin floor straight while the wood is being bent. Hopefully tomorrow I can get the firewall glued in place, might whip up some epoxy mashed potatoes for that effort.
The plans show no diagonal bracing or gussets. I plan to gusset the rear portion, the front of the plane is finished with plywood so there's no need to do anything up front. It is amazing how the structure comes together as the cross braces are added.

 

[dhal22]

All looks pretty dang good except for that Miller lite.

 

[Snoopy1]

Managed to get the fuselage formed up. Switched from coffee to Miller Lite, currently bending the front longerons with paper towel soaked with ammonia using a bungee cord to pull them together. The plywood is clamped in place to keep the cabin floor straight while the wood is being bent. Hopefully tomorrow I can get the firewall glued in place, might whip up some epoxy mashed potatoes for that effort.
The plans show no diagonal bracing or gussets. I plan to gusset the rear portion, the front of the plane is finished with plywood so there's no need to do anything up front. It is amazing how the structure comes together as the cross braces are added.

View attachment 109552

That took some doing to get all straight and square, can’t wait to take all the claps of to see what you have that is always exciting.

 

[TonyHallo]

On Monday and Wednesday we watch the grandsons, 4 and 2 years old, they were wound up today didn't get much done, spent the evening making 1/16 steel fittings for the landing gear mounts, need 12 pieces in total, still have 6 to go. I cut the blanks oversized, drilled and screwed together then milled on the mill/drill, have 6 nearly identical parts. The remaining 6 are three different parts so it will take more time. The Miller Lite did taste good tonight after a long day.

 

[TonyHallo]

Here are the first six still screwed together, the are resting on the newly installed 1/8" lite floor. The plans call for 1/8" aircraft plywood floor, just didn't see the need for that. The floor ties the lower longerons, cross pieces and firewall together. It is about 27" long and installed as one piece, was able to bend it in place. Could not do that with regular plywood. I don't plan on removing the fuselage from the bench until the landing mounts are installed.

 

[Snoopy1]

Be hard to build that plane with out a milling machine. The parts look good. The light ply will save you a lot of weight.

 

[TonyHallo]

Got a little done this AM, silver brazed the main strut bearing together, a 3/16" piece of plywood is sandwiched between the steel plates and a 3/8" x 3/4" spruced is backed, everything is jointed with 4-40 screws. Everything got painted with epoxy before assembling, the assembly got mated with epoxy and microfiber mixture to the floor and longerons. Once this cures, the rear bearing points will be located and installed.