Boomilever B/C

[PM2017]

I used medium or large DeWalt clamps (I don't know which) like these:
https://www.dewalt.com/products/hand-to ... /dwht83196
I got mine from Home Depot. You clamp the bottom edge of the testing wall to the corner of a table.

What if the table flips over?

Uhhh I don’t think anyone’s ever flipped a table...????

So I took over as the stick holder for one of our competitions, and while our table didn't flip over, it did suddenly tilt, then jolt back and abrupt movement caused our boom to break.

[dholdgreve]

I used medium or large DeWalt clamps (I don't know which) like these:
https://www.dewalt.com/products/hand-to ... /dwht83196
I got mine from Home Depot. You clamp the bottom edge of the testing wall to the corner of a table.

What if the table flips over?

Uhhh I don’t think anyone’s ever flipped a table...????

Oh my... Yes indeedy! When my son was a freshman in High School (16 years ago) we went to an unnamed competition near a very great lake! He we signed up for the first slot in the first period (a huge mistake by the way!). The competition was held in the gymnasium, and they had tarps spread all over the floor. In the middle of the tarp was a Black and Decker workmate with a piece of plywood clamped into it. The booms were to be hung from the plywood and project out over the edge of the workmate. The sand used had come right off the beach. It was soaking wet, and still had roots in it. Back in those days there were no auto-loaders, so it was scoop and dump. He began to load, and when he reached about 12 KG, the entire workmate began to tip. The E/C running the event was standing behind the workmate and immediately put his foot on the back bar and pushed it back down (immediately and violently). The boomilever and bucket bounced, but somehow did not break... I have no idea why it didn't! From that day on, that boom was known as Goliath. It went on to place 3rd at Ohio State that year, and weighed 11.5 grams

[Cow481]

Is it fine to glue something with gorilla glue and add some CA glue on the edges of the piece of wood thats being glue so i don’t need to clamp it down? I’ve been using that method instead of clamping and it seems to work fine.

[arshah2]

Is it fine to glue something with gorilla glue and add some CA glue on the edges of the piece of wood thats being glue so i don’t need to clamp it down? I’ve been using that method instead of clamping and it seems to work fine.

I use this method too. I think that it works pretty well, but that the overall strength of the bond could be increased slightly by the use of clamps. The only problem I had with using the method you described was when laminating wood, the outsides would be glued well, but the gorilla glue would have pushed the center up ever so slightly. For this reason, I use clamps instead of CA when gorilla gluing something.

[random-username]

I've been having trouble with the base, specifically the joint attachments - in all my recent tests my booms failed because they broke at the joints connecting to the base. I've just been using gorilla glue and letting my booms dry for 24 hours before testing. In the past I used zap a gap (a CA glue I believe?) but I didn't notice any difference. Does anyone have any tips about making stronger joints, or just base attachments in general? Any help is appreciated!

[MadCow2357]

I've been having trouble with the base, specifically the joint attachments - in all my recent tests my booms failed because they broke at the joints connecting to the base. I've just been using gorilla glue and letting my booms dry for 24 hours before testing. In the past I used zap a gap (a CA glue I believe?) but I didn't notice any difference. Does anyone have any tips about making stronger joints, or just base attachments in general? Any help is appreciated!

It's also important to maximize the surface area of the glue connection. You might want to use a thicker base and add pieces onto your tension member in order to do that.

[Anonymous15]

Do you mean the way Aia did it in her guide? She had these triangular pieces attached to each of her tension members to increase surface area.

Also, for clamping tension members to the base, how would that work? My base is probably going to just be a thick piece of bass, which will be connected to the tension members. How would I clamp the base to the tension members? Won't the tension members be too long (around 45 cm) to be clamped together?

Lastly, can I make my tension members perpendicular to the base at the joint where they meet, or should I angle the tension members differently? If I angle the tension members differently, I can increase surface area that way, but clamping is harder. Will attaching pieces to the tension members (like mentioned above) make up for this increase in surface area?

[TheSquaad]

Do you mean the way Aia did it in her guide? She had these triangular pieces attached to each of her tension members to increase surface area.

Also, for clamping tension members to the base, how would that work? My base is probably going to just be a thick piece of bass, which will be connected to the tension members. How would I clamp the base to the tension members? Won't the tension members be too long (around 45 cm) to be clamped together?

Lastly, can I make my tension members perpendicular to the base at the joint where they meet, or should I angle the tension members differently? If I angle the tension members differently, I can increase surface area that way, but clamping is harder. Will attaching pieces to the tension members (like mentioned above) make up for this increase in surface area?

To answer the last question, your base is probably going to be thinner than the end of your compression members, so your tension members will have to be angled outwards. To maintain a good connection, sand the ends of the base at an angle so when pressed tight against the base at the joint, the tension members are naturally angled out so they fit around the compression members.

[Anonymous15]

Got it, thanks!

@MadCow2357, when you said to increase surface area for the tension member-base joint by adding pieces, do you mean the way Aia did it in her guide?

Like this:

https://scioly.org/wiki/index.php/File: ... omBase.JPG

https://scioly.org/wiki/index.php/File:AiaBoomBase.png


Will those pieces make the joint strong enough? Also, how should I add them? Should I use CA glue to attach the pieces to the tension members?

To elaborate on the clamping question I asked in my previous post, I currently have a very large, heavy clamp (24 in) and mini clamps (3 in). The 3 in obviously will not fit around my tension members, which are around 18 in long. However, wouldn't the larger clamps apply too much force and break the tension members? (My larger clamps are very similar in structure to MadCow2357's).

Thanks!

[MadCow2357]

Got it, thanks!

@MadCow2357, when you said to increase surface area for the tension member-base joint by adding pieces, do you mean the way Aia did it in her guide?

Like this:

https://scioly.org/wiki/index.php/File: ... omBase.JPG

https://scioly.org/wiki/index.php/File:AiaBoomBase.png


Will those pieces make the joint strong enough? Also, how should I add them? Should I use CA glue to attach the pieces to the tension members?

To elaborate on the clamping question I asked in my previous post, I currently have a very large, heavy clamp (24 in) and mini clamps (3 in). The 3 in obviously will not fit around my tension members, which are around 18 in long. However, wouldn't the larger clamps apply too much force and break the tension members? (My larger clamps are very similar in structure to MadCow2357's).

Thanks!

No, though I suppose you could try Aia's method. What I've been doing is building the base between the tension members at the end, and incresaing the base's surface area with extra pieces. I've also increased the width of the tension part by adding pieces on top of and below the main member. I used Gorilla Glue for these base-tension joints, and I clamped the base and two tension members together in order for them to dry. I used a mini clamp to keep the ends of the base sandwiched between the tension members.