At Odds End [Build Log]

A few years back I received some core components for a thane build. Amongst these parts were tb110’s, some weird deck dubbed “bamboo gt flex” from the guys at propulsion, and a battery (12s3p 40t). After some shenanigans at my university this was much needed, I can’t get into details but I was big into long boarding and occasionally the culture that goes with this free spirited mindset. ugh.

So I begin the build and somewhere on the og forum it lay, but it was not up to snuff. I quickly moved to mountainboarding because of the physical aspect of it, and to this day havent ridding thane in years, expect on a surf skate. I lost my roots, as I started with small thane on kick boards.

So I dig the MTB scene, but that road feel on thanes gives me chills. (For more info on anything above feel free to ask)

Build

One of the goals for this board was a bracket designed to be used with any truck on the market, channel, tkp,rkp,pkp,atb, whatever. I love having a dedicated board, a board for a specific use case. But with this comes trade offs. I went to work with this idea and came up with 11 gauge crs brackets, that mount at various heights and various angles (deep drop -10, +10,-10,+30,+30 long wheel base, +30 drop, etc. There’s about like 6 or 8 positions idk it was a headache coming up with this mounting pattern, but I did. The called rolled steel did not paint well (imo) I used automotive self etching rim primer, followed directions, and rustoleum. Unfortunately there are a few areas that got scuffed because, yeah. they will be used anyway. They are secured with 2 9.5mm diameter stainless pipes, and 2 m8 bolts.They were designed for kingpins (3/8) but I wanted stainless and relatively cheap.

Bracket Images - more to come




This bracket seems strong, no idea, might jump might not haha, ill check out the rigidity when its mounted.

Deck

This is the deck that came with my first esk8 experience. It has mild w concave, slight camber, mini drop, and drop through. Pretty solid. BUT if I had pictures of how I received it you all would laugh. There were massive inserts in a mis matched unusable drill pattern that completely went through the middle of the deck. about 16 inserts. terrible job. my guess is this deck came from china and was a one time thing for a small company. originally the deck has 10 ply, 2 ply fiberglass and 6 ply maple. the tops and bottoms were bamboo veneer. Interesting.

Here’s a photo of the deck before I went to town, after I went to town.

I had fiberglassed the deck and it turned out decent, but the adhesion of the fiberglass to the wood was not optimal. upon impacts areas would separate from the deck, making it non structural. My problem was polyester stinky fume resin.

So I peeled the glass off carefully, to reuse later…

The deck was stiff and good all that jazz but a bit boring for me. I cut the nose and tail to make an Idea style deck, accommodating my brackets.

I messed around with the deck for a bit sanded it, painted it, sanded it, wood burn, what have you. My conclusions were

Apply fiberglass to bare wood.


I also wanted to take out some wood from the core and experiment with some xps foam I had around. The pink kind.

Stringer

Soo, I take wood outta the deck, who needs a deck. I wanted the deck to be light, strong, adjustable. The answer to my tinkering needs is a stringer. Why?

The stringers contains plywood in the areas where the brackets mount, acting as a built in riser, which is necessary given my design. Its also constructed of 4 ply of fiberglass, and yours truly, great stuff.

I used the bottom panel of fiberglass which I previously removed as the base because it conformed to the deck, and then flattened out some fiberglass on the road facing side so the brackets mount flat. I have more pictures just need to dig them up.

I decided to drill holes in the foam and let gravity pull som epoxy through.

Shout out to my broken skim from youth for inspiration,

Deck finishing More to come

So I went for clear epoxy based resin this time. the results were much much stronger, in terms of adhesion.

I glassed a lot with cloth and used mat to enforce the foam and truck holes. I don’t have much photo from this stage its hard to document when working alone.

also first time with frit.


Battery

I have 13 6s 1p modules ( samsung 30q) from battery hookup and I need to order supplies but also have some batteries on hand not sure of my direction. Either, 12s6p 30q, 12s3p 40t, or 12s 4p p26a.

Unfortunately my original battery from propulsion boards is on its way out. It only charges to 49.1 volts, ugh. can’t figure out what’s wrong each cell is reading higher than 4v fully charged.

Misc

I have 6374’s on hand, which will work for thane (tb110s) and will be using a 14/38 set up.

I want to mold an enclosure for sed battery, either top mount or bottom not sure.

At the moment I will be using 15.2 inch trucks from flipsky and dickyho mounts, as well as a storm core 60d. The brackets allow flexibility to fine tune which truck is right for which build.

I have lots more coming up regarding this project, its current state is pretty clean given what its been through. Thanks a bunch for anyones interest, id love feedback on my brackets and ways to improve, I’ve already came up with a few.


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I’d be very careful with those endplates - the way the load is purely on those bolts and the sheet metal there puts a BUNCH of stress on a thin cross section of metal. Could bend or wear over time.

The pins are to take the load, there is .5 inches of 3mm steel preventing the bolt from either direction. Im more concenred with turning forces than veritcal/lateral. Time will tell.

The way the stress is distrubuted is like a bridge… seems appropriate. Idk

Edit: my bike frames are not as strong as these or thick and they hold on the tail mounts.

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I’d do the math on it - with the pins that close together, the required load on the pins to resist the torque on those mounting plates is going to be immense.

Go for it, math is math tests are tests.

Sheer force of 2 10mm stainless steel rods?? Math

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17 potatoes

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^18* (carry the one)

im not sure what i just read, but i like it, more power to you .I have zero expertice here, my only 2 concerns are vibration and that over time you may cut through those rods as you will be applying (im at a loss for proper terminology) a shearing force on the rods. What i do know from operating big ole tractors is i have seen rods/pins in this configuration fail,im sure metalurgy has a tremendous application(poor terminoligy again) how much do you weigh? are you a fast rider? can i talk you into a third rod? GOOD LUCK,I APPLAUD your creativity. Keep us infomed,pleas, im intrigued .also i dont kow shit, im just trying to make sure you are safe in an unsafe activity

EDIT: CAN YOU AD A BOLT THAT COMES FROM THE BOTTOM,SO ORINTED 90 DEGREES TO THE PINS? IT COULD BE STILL ADJUSTABLE.DONT MIND ME IM TRYING TO HELP.

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im concerned with shearing and metal fatigue from vibration, the degree i have from Lousiana po white tash university says, i was born in Lousiana,so failure is something i feel qualified to speak on with authority

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No i appreciate help, in this kind. And others concern for my safety, but check the math isnt really applicable at this stage. I ride diy surfskates and consider a kingpin when orientied properly a good standard for shear force. Have bent many and will bend many more. It takes a bit but have never seen catastrophic failure. I cant image a clean break. Can you? Srs.

I work with this stuff daily as well. No degree, just experience. I studied math and design but my degree is in philosophy. I learn/approach with core principles.

Kingpin failure
Triangles
Material
Experience.

Everyone has a degree these days. But, anway describe your third pin more, you mean perpindicular to the ground?

For refrence since everyone asked i placed first years ago in a bridge design contest, prior to university study.

And fast and hard rider or at least above average. Weigh 240 rn it fulcuates. Have you seen my minibike? Or surfskate in analog photos?

I will also be jumping/yard testing before any road riding

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The 10mm pins like people are saying is something to keep an eye on.

Its not the static force, but impacts that will shear them, not all at one time, most likely.

Your design is like a pair of scissors, I designed something similar for a weight bench…had to rework 500 benches from China in our American warehouse because people sheared the handle pin.

FEA and math are not easy to do on something banging down the road.

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Why do hitch pins work?

excellent point.

There is not much leverage, and the loading is very low compared to the diameter.

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Yeah, they are 4lbs each as well, its a lot of metal.

One pair

Also in order for the pins to bend, the bends in the plate must bend as well. They were bent with hydraulic.

I can definitely see them shearing clean, if possible do not have threads in the shear area. I have 2 years of high school so I’m pretty much an expert. I think if you replace them often you be ok, yes I was thinking about perpendicular to the ground but I have only glanced at the design, I’m brain storming and I dig ditches for a living, bear all that in mind

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Your making sense, be confident!

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I’m confident, but everyone is an expert, I am what I am. I’m not exaggerating and I want my advice to be taken with context

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Most people including my gf have 8 or 12 year more education than I do :stuck_out_tongue_closed_eyes:

Everyone indeed an expert.

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I do have 27 years experience as an operating engineer, practical experience is quite useful

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