Originally Posted by Prof100
The scratchbuilt guys use dowels all the time because they are trying to keep costs down but they still want strong. Look for birch (not poplar) dowels at your local Woodcraft store. Birch dowels are much stronger that poplar dowels like you buy at Lowes or Home Depot.
I had a 1/4" oak dowel from Home Depot
for my wing spar for a while. I did quite a lot of aerobatic maneuvers and it did not break, but it wasn't very stiff. It flexed a lot. When I took it out to replace it with a CF tube, it was warped. So, I'd say it will work, but it's not the best option for performance.
I ended up getting 2 CF tubes from Goodwinds also. I put the smaller tube inside larger, without fitting problems. They had the best price with shipping included. Here are the 2 tubes I got (Goodwinds CF tube link
- Carbon: Pultruded Carbon Tubes: 020971 Pultruded Carbon Tubing: Description O.D.": .2810";Length:
32.5";I.D.": 0.186";O.D.mm: 7.10mm;Wt./gm: 29.9 gm $5.49
- Carbon: Pultruded Carbon Tubes: 020000 Pultruded Carbon Tubing: Description O.D.": .1800";Length:
32.5";I.D.": 0.112";O.D.mm: 4.57mm;Wt./gm: 13.0 gm $3.79
I did have to slightly enlarge the wing spar holes using the sand paper method from thread page 1, but it was totally worth it. I've got a really tough spar now. I only wished it was cheaper.