10 Feb. 1995|
Balsa wood joint types,little wizard woodworking metal detector,cabinet making course glasgow - For Outdoors
Can you PLEASE report on the Miter Joint BEFORE Friday (2 days from now) I need it for a report im writing and i can NOT use wikipedia!
I haven’t done a lot with toothpick bridges, but it seems to me that lap joints would be the way to go.
What did you mean when he said “Yes, the sandwich would be stronger than just 1 lap joint.
Anyhow, onto the question: you are very pro lap joint, but intuitively it seems like for compression joints an end joint would be stronger, since you would literally be pressing the chords against the end joint.
The last couple years I’ve been building exclusively with popsicle sticks, which require lap joints.
Also, if it is allowed, you might want to consider mixing a little water with your wood glue.
Balsa bridges tend to break for two reasons, a member in compression fails, or the joints pull out. A model bridge contest will be held at my university and I would like if you could give me some hints for the joints.
On a bridge, you want to make sure that the joints are clean and there are no gaps between the wood.
There is no issue with craftsmanship or with time, but I don’t want to use a lap joint if, because of my glue, it will not be the strongest possible joint. As one can see from the picture, it clearly degrades the integrity of the wood that’s been notched. I’m making a toothpick bridge and need to know whether or not to use lap joints, end joints, or possibly gusset.
I’d think that you would want as much overlap in the joints as you can get because the surface area of toothpicks is not much to begin with.
Also is it possible for you to post a picture where a lap joint was actually incorporated into the structure.
I have recently been given responsibilities for a balsa bridge-building team at my high school, & have been hitting the inet for a crash course. I would think the twisting of the truss as the bridge flexes would work counter to the strength of the lap joint, but it sounds as if I am incorrect. I don’t like gluing to Balsa wood end grain, which is what you would have to do in a end joint. I know it sounds weird, but it can actually strengthen your joints by thinning the glue just a little bit.
Typically the face of balsa wood is not very strong, which is why you want your glue to go deep into the wood.
Depending on the type of glue you use, the joint is only as strong as the face of the wood.
You cut half of the wood off the part of the strip that will be the actual joint, and then connect the two pieces at those joint parts. Don’t think that you have to use all the wood, as it sounds like you do not have a minimum weight to hold.
Granted, I don’t think that toothpicks are high quality wood and there is probably a mixture of densities. I like your idea of the t shape on top, however we’re only allowed to use 2 pieces of wood.
You can also help avoid tearing by making sure your lap joints have plenty of surface area for the glue.