First build | Landyachz Drophammer | Torque 6374 190Kv | 12s2p | Abec flywheels 97mm

Cool yeah OpenSCAD is a bit of a clunky sort of UI but basically can put in the parameters you want for the pulley type and number of teeth and everything then hit F5 and it will remake the model, once you’re happy with the parameters you hit F6 and it processes it into a mesh then there’s a button for STL export. There’s also an openscad file for a rack and pinion setup I’m planning on using just really useful for simple parametric parts (especially when someone else already did the coding/scripting)

A friend suggested me a program called Adobe fusion 360. I will do some more research about, but at first glance they look much better for the work I am doing.


I printed the shorter motor mount but I noticed some mistakes, the internal ring is too small and doesnt fit the truck, also the role for the screw could be better designed. So I will probably update the project and print again.

The 13T pulley came out almost perfect. The belt fits without any problem. The only downside is that the printer app closed some open holes and I will have to drill the shaft role again

2 Likes

Gotcha yeah plus side with ABS is it is workable sort of like a clay or something (guess you could say it’s the aluminum of plastics). Drilling shouldn’t be much of a problem so long as the bit doesn’t grab in too deep and crack the part. Regarding OpenSCAD I kind of use it as a sledgehammer, that’s to say it’s a great tool but limited uses, basically if you need something that someone has already modelled in OpenSCAD or you need to model a lot of a thing that is similiar but with 1 or two variables that drive the model that change then it’s great. Basically I use it for generating one off parts like a gear or whatever and then export the STL and then pull it into something like OnShape or Blender where I can work on more complex models with UI that “makes sense” for the job.

I’m primarily a web dev but have been messing with various CAD software on and off for years. Messed with AutoCAD as a kid on my Dad’s computers and used to bother the computer graphics guys across the hall in college all the time to show me how to do stuff in 3DSMax. More recently I’d been taught how to find my way around pretty quickly in Blender so I was using that for modelling 3D prints but it takes a lot of forethought to get things done in there that are pretty trivial in other programs and has some really crappy bugs with things like the boolean operator that make it frustrating to work with.

OnShape is a browser based tool and free to use for non-commercial purposes and is parametric, constraint based modelling (similar to Fusion360 from what I gather). I’ve heard good things about Fusion as well but I’m a Linux die hard and so far they have no browser version of the software released (or linux version). I wrote a big rant to Adobe like 5 years back about how they should get on Linux and that most people are using Windows and other shit proprietary systems because they are locked into the Adobe tools they learned and can’t use those tools on Linux, hence no Linux adoption on the desktop… anyhow I’m going to get into my whole Linux thing so I’ll just stop… But yeah Fusion 360 :thumbsup: should be good if you want a cross platform browser based thing OnShape is pretty similar and free to use for us tinkerers.

I used to love AutoCAD when I was in the architecture university, some year after I want to stay away from it as much as I could

This fusion 360 actually is really simple and powerful. Basically, you sketch all the dimensions you need and start extruding and chamfering as needed. Feels pretty good to model things precisely again.

After the suggestion of making the motor mount thicker, I decided to start it from scratch on Fusion to test it’s workflow the camera movement is really weird, doesn’t look like any 3d program that I used before, but other than that is great

Now that the mount is thicker it will require new bolts for the motor and to lock the mount into the truck, I am thinking on getting m4 20 for the motor instead of the original m4 12 and m5 30 for the mount itself.

I also still need to figure out how I will attach the battery on the deck but I will wait for them to arrive first, it is expected by tomorrow since today was a holiday

1 Like

can we borrow the 3d drawing lol :smiley:

For this last one? Sure, I can totally share it, I am only afraid if that the clamp system I did will hold it, now that I tested the motor the torque seems way higher than I was expecting and I believe it may rotate a little

I may need to add some teeth there or make it as two pieces instead of four.


updated I printed the second version of the mount but I am afraid it will not handle the torque. I am not sure how much the motor tries to rotate so I may need to update the design. There is only one way to test.

I also printed a cap with the logo of the game that I work for the drop-thru holes that are exposed on the deck, but again another mistake in the calculations. The trucks support both patterns of hole, but when I unassembled it I discovered that my deck doesn’t. So it needs to be bigger and follow the old-school pattern.

Also, are those number correct?

my battery is a 12s2p 6ah 44.4V 266.4wh motor is 6374 190KV

1 Like

You can use Acetone to “ABS weld” the parts together once you have everything aligned and tightened up as much as you can without cracking anything. Just do it in a well ventilated area you basically just put some pure acetone in a glass and use a brush (not made of plastic or at least not ABS or something that will dissolve in the acetone) to brush a little acetone onto each part you’re going to join then just clamp them together and let the acetone evaporate out. The acetone will melt the top layer of the plastic and it will chemically bond into one part, it will be at least as strong as the print layers.

You can also make some “abs juice” or “abs slurry” by adding some abs scraps into the acetone in a jar and again keep it in a well ventilated area and sealed up (slightly exothermic reaction I guess so good to add the ABS kind of slowly or just do small quantities as you need it). That way when you “paint” it on you are adding a little material as well since it will tend to sort of melt away. Also the brush will likely be ruined once the acetone evaporates from it the plastic will harden in the bristles, if you let it sit in acetone for a minute or so it will soften up again though so it just becomes your plastic bonding brush.


Also think your battery cut off is pretty low what kind of batteries were you using again? need to do the low safe point * 12 to get your cut offs, 30-33 would be for 10S with li-ion I believe, LiPo better to stay in the 3.6-3.8 range on the bottom per cell.

this is actually a great idea, I will buy some acetone tomorrow

it is from DiyElectricskateboard, it says " HHS Li Ion 18650"

Did some searching around looks like 3.0 is the absolute bottom I’d probably go with 3.2 - 3.5 as the per cell cut off limits and then check how many mAh actually go back into the battery. You want to ideally only drain 80% or so of the charge just to maximize the life cycle and limit the chance of ever dropping any given cell below the 3.0 a which point it will degrade and will probably need to be replaced which usually means replacing more than the one cell. So with 6Ah after you get back to recharge you should be putting about 4.8Ah, if it’s more than that you might want to increase the cut offs, if it’s less than that you can decrease the cut offs.

So 3.2 * 12 = 38.4V and 3.5*12 = 42V

Set those as the end and start cut off values, then it will reduce power when you get down to 42V and cut off power when it hits 38.4V. If you want to be more conservative could cut off between 3.6-3.8 which is the safe range for run of the mill RC LiPo batteries.


You basically just want to be sure you don’t ever get any cell going below the safe voltage level for any extended period of time but need to keep in mind there is voltage sag when you’re drawing a lot of power out of the pack and you don’t want that sag to ever go below 3.0V, so if you get a .5V dip whenever you’re cruising then you’d want your low cut off at 3.5… hopefully that makes sense. Could check with DIY on what they recommend for safe minimum voltage.

I went to a huge construction store here called Home Depot, and struggled trying to find the imperial sizes to the metric system. There is no progressive pattern on the numbers, and it is a mess how they name them. The numbers are closer but they don’t match, my 3dprinted mount cannot be used because I have no way to attach it to the motor. I tried screwing and they cant handle the torque because the holes are too tight.

This is me trying to take it off after the second one broke while I was complaining about the imperial system =]

So I went up with the original mount. When adding the motor pulley I faced couple issues, first there is a metal piece that comes with the motor and works as a lock mechanism for the pulley, that piece was too big for the space on the motor shaft, I don’t know how this happened because it came with the motor on the same package, they were supposed to fit together. Anyways, 1 hour later after sanding, it ended up fitting.

The second issue was my fault; the screws that came with the pulley are not flush with the diameter, and they don’t have enough clearance from my 97mm wheels. So I had to skip using them. The pulley got it so snug on the shaft that I doubt they will even be separated again.

The first attempts to roll the wheels I could hear some strange noises that were matching with the frequency of the spin, my guess was that the belt was too tight and after releasing the tension the noise disappeared.

I am using the nano remote and it is hard to keep a progressive acceleration, feels that the controller is too sensitive and it goes from zero to “trying to trow me away from the board” too fast. I wonder if I can change the acceleration curve on the vesc or maybe swapping to those gt2b controllers and get a more smooth acceleration.

1 Like

Check out @Ackmaniac’s firmware

Will do. Just need to learn how to do it and if it is possible to revert if I don’t like

I tried today reducing the motor max and motor min by half and it worked, made the acceleration and brake much more smooth, but the board felt weak to the point that could not stop going down on a hill.

changed the firmware to @Ackmaniac 's and tomorrow will start testing it.

I also started tearing apart my GT2E controller and I was wondering: Are those functions necessary?

I guess only the binding, power and led lights are useful. Anything else?

1 Like

the vibration of the road untightened the motor mount and messed with the alignment. I had to come back home carrying the board =]

1 Like

Motor mount bolts should be installed with Loctite always!, I see your motor mounts are abs, I’m not sure if that’s going to hold though

The one I was using are the Enertion, they had Loctite but I think the problem was something else, they were mounted too close to the middle of the truck and that part is not flat enough, so the contact area with the truck was reduced. I filed that part it apparently this plus the loctite fixed the issue This is where I started filing

I still want to try the 3d printed mount, but I am getting into multiple issues. I used Loctite on the motor pulley screws and I cant take them off now… I tried warming up them with a soldering iron and only worked for 1, the other three doesn’t want to move. Apparently acetone works, that will be my next test

On the meantime I decided to design new wheel pulleys to my wheels

so I modeled the wheels and made the pulley no a way that it fits exactly the shape

I am not sure if going that high with those “pillars” inside of the wheel are a good idea.I will have to test

1 Like

I designed the pulley to have nuts inserted and utterly failed; the nuts are big enough to hit the truck and don’t allow it to spin. I will try next without the bolts and see if the pastic can hold the screws.

1 Like

I updated the design without the nuts but I made the screw holes not tight enough. After a week it got a little eccentric and broke

1 Like

updated the design with screw threads and more contact to the teeth area

1 Like

Looks good if you still have problems with delamination (breaking across layers) you may want to consider doing a mold of this (3d printed part) in silicone and pouring the urethane plastic part out of a mold, gets rid of the possible delamination issue and you can get different types of urethane plastics that are tougher or more flexible depending on what you need here. I’ve been playing with this for the last few weeks and it works well for certain shapes, with this one could do a two part mold pretty easily since all the holes and parts that stick out go in one direction could mold in the orientation you have it on the table. Also once you have a mold of a good part can re-use the mold 30-50 times from what I’ve read (have used one at least 15 times without any issue yet). Initial cost for some silicone sampler pack an urethane plastic will be pretty high (like $50-60 for both) but should be able to probably make 10 or so of them with the sampler size of urethane plastic that gets poured into the mold so if they are good enough can probably get rid of them for $5 a piece and recoup your money.