This kayak to sailboat conversion is well done and makes for an interesting project. But even if you’re not going to be hitting the water on one of your own, the construction techniques are a useful resource to keep in mind. Many of the alterations were done with a plastic welding iron.
[RLZerr] shows off the materials that went into the build right at the beginning of the video which you’ll find after the break. His kayak is made of High Density Polyethylene and he uses other HDPE scraps, PCV parts, and even some aluminum to make everything. To weld HDPE together he uses a plastic welding iron that is like a cross between a soldering iron and a hot glue gun. It has a pad tip that gets hot enough to melt the plastic, but also includes a channel through which additional HDPE filament can be fed to bulk up the connections.
Additions to the kayak include a centerboard, rudder, and mast. The sail is a plastic tarp attached to the PVC mast which has been stiffened with a wooden shovel handle in its core. The rudder and centerboard are aluminum attached to PVC pipes using JB weld. The boat catches the wind easily, but without outriggers [RLZerr] must be careful not to let a big gust swamp him.
Continue reading “Kayak to sailboat conversion shows how to weld plastics”
There are so many good ideas crammed into this project its hard for us to believe this isn’t already widely used for critical welding applications. Traditional welding masks simply filter out light to protect the welder’s eyes. This mask doesn’t have a window in it at all. Instead, the mask includes two cameras on the outside and two LCD screens on the inside. It filters light by processing the video which lends itself to that grab-bag of features we mentioned earlier.
Possibly the best of the system is its ability to selectively filter the brightness of the weld. What this means is that areas outside of the welding arc appear at a normal brightness level, whereas before they would have been greatly dimmed. A demonstration of augmented reality is also shown, where a computer monitors the welding surface, giving the welder a target to follow and measuring the distance between the weld and the filament. The video mentions that an FPGA would be well suited for the image processing, making us think this could be produced at a reasonable cost. After all, they already use X-ray machines for some welds, we’d bet a set of these helmets could be supplied to a crew at a similar cost.
We don’t get to see Blacksmith hacks around here too often. But even if they were rolling in on a weekly basis we think this one would be considered the special expanded edition with full-color centerfold. The sixty-five images in this coal forge build log are all commented and just begging to steal your attention for part of the afternoon.
The build mostly involves fabricating a system for injecting air into the forge and providing a mechanism for evacuating the waste ash. [BillDaCat] starts with a 3″ pipe as the ash dump, adding a latching door used to empty it when full. He then welds together a metal trough with a slotted bottom to hold the fiery fury, attaching the ash dump below. He uses a plasma cutter to add an opening in the upper portion of the ash dump for a blast gate.
If you’re excited about his build you should also check out the metal pour and the induction furnace.
Here’s something that may be of interest to all the reprappers, vacuum formers, and other plastic fabbers out there: ultrasonic welding of plastics. If you’ve ever wanted to join two pieces of plastic without melting them together with acetone or screwing them together, [circuitguru] is your guy.
Ultrasonic welder setups are usually reserved for companies that don’t mind spending tens of thousands of dollars on a piece equipment. There are smaller versions made for heat staking – melting plastic pillars into rivets on the work piece – and [circuitguru] was lucky enough a somewhat reasonable price.
Because the heat staking gun was a handheld unit, a rotary tool drill press was put to work. The end result is a relatively inexpensive way to join two plastic parts without screws, glue, or solvents. The bond is pretty strong, too. Check out the video after the break to see [circuitguru] join two pieces of a plastic enclosure and try to tear them apart.
Continue reading “DIY ultrasonic plastic welding”
This project really puts an end to arguing over who has to ride in the back of the tandem bicycle. We challenge you not to smile while viewing the maiden voyage that [Carlos] and his daughter take on this side-by-side bicycle. The video can be found after the break.
It certainly makes a bit more sense than an over-under tandem, and the fabrication process is really quite manageable. This requires alterations to the seat, handle bars, and pedals, but the majority of the bike (frame, gearing, fork, wheels) is unaltered.
The cranks have been replaced by a custom welded cam mechanism that reminds us of how the pedals on a paddle boat work. Both riders must pedal at the same time and rate. To give each a place to sit the seat post was converted into a T bar to host saddles to the right and left of the frame. Finally, the handle bars are the most complicated of all. Extra framing was welded onto both sides for the front tube to provide a place to mount two pair of handle bars. One of them is fixed in place, the other can be turned, using a lever mechanism to steer the front fork.
It looks a bit awkward to get started, but once both riders are up it seems quite stable.
Continue reading “A bicycle built for… Siamese twins?”
Someone let [Tane] play around with welding equipment and bicycle parts and look what happened! He built a diminutive velocipede. Now that’s just a term for a human-powered land vehicle, but the term fits a bit better as this is missing most of the stuff you’d expect to see on a bicycle.
He started with a mountain bike and a kick scooter, then went to work on both with a hack saw. A bit of welding and angle grinding left him with what you see above. It’s still steerable, but missing are the cranks, chain, and brakes. That’s okay though, the bike is low enough for your legs to reach the ground – you start it up and come to a stop Fred-Flintstone-Style.
[Tane] originally meant to add electric propulsion but didn’t quite get around to it. There’s always the option to add a hub motor to the rear wheel if he has the time and motivation.
So you fancy yourself as an amateur engineer? Been working on those welding skills for a while? The real test is to trust your children’s lives on a roller coaster you’ve designed and built (translated).
Now we’re not talking some tired old carnival ride like the teacups. This is a full-blown roller coaster, complete with an upside-down loop. The ride starts off with a chain-lift to the top of the garage/barn roof. From there it’s off and away on the single-rider train. We’d recommend keeping your hands and feet inside the car… if there was a car. The ride utilizes an automobile seat, but you’ll have to settle for a lap-belt as there’s no shoulder restraint here. We’re a bit wary of the track footings – we’d bet they’re not well anchored in the ground – but the fact that the entire length of track has been painted makes us think that [John Ivers] might have known at least a little bit about what he was doing. Don’t forget to catch the video below the fold.
Update: Much better video now embedded after the break thanks to [Tom 101’s] link in the comments.
Update: Source link changes to the original thanks to [Mike’s] comment.
Continue reading “Entrust you kid’s life to a homemade roller coaster?”