Yea I saw lots of info about aluminum, graphite etc. Each in specific quanities can add thermal absorption, electrical conductivity etc.
I mean, when we talk about epoxy I feel like we could just say… fiberglass gives some abrasion resistance to epoxy too lol. Im very curious what that MG chem epoxy is like. They have several others that are flame proof as well
There of course has to be a conversation about weight. For this enclosure, the majority of the volume is consumed by components. Theres an evo enclosure next to me with a 7p 30q, unity and a D140 and I think theres space for extras of each of those. For that I think a combination of open cell foam and a urethane pour would be good or youll just add too much weight
Based only on my experience with JB Weld, which comes already with steel powder in it, it shouldn’t add much conductivity, if any. JB Weld seems to be an insulator for maybe everything except lightning, based on my observations. I don’t know, maybe under some circumstances it could conduct ??
I’m curious as well… all my tests with JB weld shows almost no conductivity, but wrapping it all around the connections of a battery has me wanting someone else to do the science…
There’s a rating for this expresses in volts/area I believe. It’s written in some tech sheets for high end polymers. Represents the amount of voltage needed for conduction and most of the ratings I’ve seen for silicone and urethane have been in the 500V/mm or something wild like that
Had a bit of a set back yesterday. I wound up with a bit of a leak in my vac bag overnight and my most recent laminate is not adhered to the board consistently. Whats worst is that its most effected around the edges which is the most important part of it. Ill be stripping most of it later this week and will need to reapply from there up.
I have only one section left to apply urethane to within the deck but need to do some fiberglass repairs first before I pot this section.
For the 3DS heat sink I need to fill the incorrect bolt holes and also fill the eboosted logo. For the heat sink, think I should just eliminate the bolts through the enclosure all together and just bond it into the hole. Or should I keep the sides only or all 6 of the bolts. Its a snap fit into the hole and will get urethaned in place to seal it anyway
Also will be installing the GX16 fast charge port and figuring out the location of METR antenna, puck receiver and any thing else that will need mounted around the unity before pouring urethane in this last spot.
I popped in the 10 groups that I have the spaces poured for. Even flipped the enclosure and was happy to see they all stayed in on their own. This is even before heat shrinking! Really happy with how this turned out
Back to the beach tomorrow. More this weekend. Mostly just trying to finish up the deck now. Still waiting on my BMS and METR both of which are stuck in the USPS lost and found right now it seems
I’ll continue ripping this lower ply off later in the week but took a moment to check my progress and refresh my memory on the final plan.
Blue is where the enclosure touches. Black outline indicates the cutout I’ll be doing with the router. You can see that the laminates I’m adding will mostly just be on the outer 35mm of of deck once I rout the pocket out
I’ve added 4.5mm to the bottom thus far but lost the last layer (1.5) and will need to strip it and work back to the previous 3mm layer. That big pocket will get back all my lost flex.
This fuck up and my removal attempts with a chisel have really effected the area needed most. Which is a bit frustrating today. Sigh, we will make it right. Some large areas on the edge fractures while I was chiseling so I’ll see how far down I need to get to make it right
This smooth on universal mold release is really excellent stuff. I’ve had no issues with the urethane to 3D printed battery plugs or with epoxy to metal. Used it to free the heatsink and the screws from epoxy and worked perfectly. Fell right off and the material left behind looks great
I had to grind this area in the very back of the enclosure to get the heatsink to sit flat on the bottom. Laid a small bit piece of fabric down, wet it out and bolted the heatsink up. I let it drain down against the edge of the heatsink and build up there a little.
Making progress. Filled the enclosure logo. Installed the GX16 plug. One of my last items will be pouring the final section of urethane for the last two P groups and around the unity. I need to paint it, layout the last few items in that area and check fit once the BMS arrives. Anyone have a good way to strip this paint quickly and cleanly?
Last layer is on the bottom, which will need some more blending before I give it a final finish. Still debating that.
Extra deck holes and prior enclosure holes filled with epoxy and sawdust ( from this project).
Picked up some PCBs and Maytech motors from @DerelictRobot !
Time to make or buy a gasket so I can install the enclosure.
With glue up of the lower veneers complete, I had more material that I could safely remove to make room for components. In total, I added approximately 6mm to the deck and only about 3-4mm to the tongue and drop down areas. After the addition of those layers (4 in total with one partial fiberglass) the deck was very stiff, even without the enclosure on it. It wasn’t completely stiff, but quite solid. I expected this, and that’s why the pocket is large to give back most of that flex.
Cutting the pocket in the deck
Using a dewalt router, a 1/2” straight bit, a 1/4” radius half round bit and a 1/4” straight bit I cut out the pocket. I started with the smaller straight bit and cut the outline to the final depth. I followed a 3D printed jig I made that had a slight taper and made the pocket 180mm at the ends and 170mm at the center. After the outline was done I followed the jig with the half-round bit to give myself a corner with a nice fillet. Went a few mm deeper in the rear where the pocket will get deeper. From there, I removed the jigs and began removing the bulk of the material. PS… this was a lot of wood chips. If I had the tools or the right location, yes I could’ve saved a lot of work if the pocket could have been there already cut out during glue-up.
In hindsight, I should’ve taken the time to make a sled for the router. I wound up using some flat bar to run the router on at the end. But in general, I’m basically removing all the material under the router and the deck slopes away all around this area. Meaning your surface to rest the router and keep things level get smaller and smaller.
I removed all 6mm of the new veneer on the majority of the deck and cut about halfway through the bottom layer of the original deck. 6.5mm through that area and in the rear I removed all 6mm of the new veneer and an additional 4.5mm of material.
Im very happy with the results! After the pocket was cut out its quite flexible. The front feels the same as stock if not a touch softer and the rear feels softer at the moment. Theres a short clip below showing off the flex some. I will be adding a 2oz layer of fiberglass weave to the whole bottom of the deck tonight. Im not jumping hard at all on it until that layer of fiberglass reinforcement is on. Im under 170 as well. However, I gave it a few solid bounces to really see it bend and the veneers added bent without making a sound. Success.
Next for me to fix is the enclosure mounting hardware. These tapered sides have given me trouble. Im currently using the bolt through from the top type that eboosted includes with his stuff. These are just for riveting in place normally. The fender washers on the enclosure being sunken in give very little room for error with the bolts. There isn’t a lot of wiggle room with the angle of the bolt or its position. Ive installed hardware only to have 2 different times where I encountered a cross-thread that made the insert spin in the deck. For one, these arent steel rivets, theyre brass i believe – and using SS bolts. Just annoying to have the enclosure bolted up, to then remove it and not be able to get it back on…sigh …
Worth mentioning, trucks are finger tight with two bolts. I admittingly took out a mm more than was needed in the back. The removal for the majority of the front cavity is pretty negligible. And they were pretty flexy to start with, like touching the ground in the center flexy
I am planning to FG the entire bottom of the deck and I still have a full layer of maple to add to the top of the deck planned. I havent decided how to finish this deck off just yet, so I may use the nice piece of carbon fiber I have. By the time the bottom gets FG and the top gets a layer of maple, the enclosure gets bolted on, it’ll stiffen a lot from here. ( you can just spot the last layer of maple I have in the roarockit box under the couch)
Battery will be flexy of course.
As much as I like carbon fiber and I dislike fiberglass, I honestly think fiberglass is a lot better for esk8 usage. It’s transparent to radio waves. This is very important.
Can you use radio devices inside a carbon cavity? Maybe. But why? If your life depends on stuff working, I’d give it every chance to work as best it can, and one way is by using fiberglass instead of carbon fiber. Unfortunately.
Everything prepped, final layup on the bottom was today. Unfortunately this was a mess- the dog must have walked on the vac bag (normal vac bagging film) and punctured it somewhere. After doubling up the butyl tape seals on both ends and not being able to hold a vacuum I had to switch bags and make a new one quickly in real time. I was definitely past the working time of the 206 hardener by the time I got a consistent vacuum.
This is using the roarockit pump to create a static vacuum so there’s not concern for dry areas since I wet it out by hand. It may mean that most of the excess epoxy was left behind and worse case, the FG wasn’t held well to the surfaces or the curves in the pocket I cut. We will have to wait and see
Layup was 4 ounce weave from tail to 1/3 length of the board. Then just the drop down to 1/4 length. Then a layer of 2 ounce weave over the whole deck end to end. Peel ply and then breather
I left it outside on the hood of my car in the shade for the first 3 hours or so. It’s ambient about 90* today and it’s 69* in my apartment. Hence the writing
After the vacuum failure on the FG the other day I realized I was stuck because I was out of bagging film. I did a dry layup in the Roarockit vacuum bag which couldn’t bend enough to pull the mat tight in the cutout and I would’ve wound up with the same result again. So while I waited for supplies from Fiberglast.com I got the upper veneer prepped. I soaked the veneer in some warm water in the bath tub to soften it and into the Roarockit bag it went with the board. I left it wet for the first 4 hours and then I added a bath towel inside the bag behind the new veneer to soak up the moisture and dry the veneer out while its being pulled to shape in the vacuum bag. If you wet a veneer and just let it dry, it will substantially warp. This way of pre-forming it and drying it out is the best way I’ve found to meet these complex contours during the glue-up.
Also received some stainless m5 threaded EZLOK inserts which ill be installing. Once this is pre-formed ill fiberglass the bottom, then install the upper final veneer.
Getting closer! The BMS that the USPS lost finally showed up. Thank you to @thisguyhere. Once I was able to check clearances Im ready to finish pouring the urethane. I didnt want it to be the same depth around the unity because I have other items like the remote receiver and BT for the BMS to create a spot for as well. To accomplish this, I 3D printed a part to attach to the heat sink (which made sure it was square) and I used some clay to fill the gaps around it. This will be the sport for the main negative and positive P groups. Tooth picks were just to gap the battery plug away equal distance
