Hydroelectric Intake 3D Printed Coanda Screen Tiles
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- Опубліковано 13 лип 2024
- After my series of videos about making this intake i was contacted by Bjørn who has been working on his own small hydro system and has been designing a 3D printed coanada tile. The design is still in the early stages and i am field testing it at the moment. We already have some great ideas for some improvements and once the design is finalised it will be available to print (open source)
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I Just wanted to thank everyone in this comment section. It has been a fine example of a good community. Lots of good ideas that will likely be actioned. And i have not seen a single person call anyone an idiot :) Brilliant
Hey Kris. I'm particularly enjoying this project as I just love hydro technology. I've never been ivlvoed in the tech side of designing them, but used to be involved in the planning and development of them (before I damaged my spine in a white water kayaking accident and life changed somewhat). It's just such a good technology, particularly for small scale personal sustainable use, like you're doing. Great to see you spending so much time getting it right!
Anyhow, I make a lot of mechanical parts with 3D printing. It's a great tool and I'm really impressed with what you guys have come up with here. Couple of thoughts to take or leave:
1) if one of the 'fins' were to snap off and then get sucked down to the turbine, would it damage the pelton spoons? If so, do you need a secondary conventional screen or filter on the pipe just to stop anything bigger heading down the pipe? Similarly, the fins may flex a little in the middle and could possibly let some bigger detritus down, so maybe a secondary screen would mitigate that too?
2. You mentioned printing the final design as one piece. One of the limitations of 3D printing is some angles and arrangements aren't so easy to print or don't print do well. The really smooth finish of the top of each fins looks great and you mentioned it helps the water to shed and to shear. If you print those as one whole part and those fins are set at an angle, it may not be possible to get such good, smooth surfaces. It might not be a problem, but it could be depending how important a really smooth surface is, so could be a trade off against winter water ingresss and freeze/thaw. Not sure what might be a bigger risk?
Just mentioning incase it's of help. May well be that you've got it all in hand already, in which case just ignore me!
A' the best for the Scottish Highlands. Keep up the great work 😊👍🏻
Edit: Forgot to say, PETG or ABS (or ASA) should work fairly well for this in Wales, but I'd avoid PLA.
Hi, Thanks for your input! I can hear that you are an experienced 3d printing guy. Printing strategy is always a challenge especially when printing slopes and avoiding supports.
I have tried to print the tiles the other way around and the surface is more rough as expected. It does not seem like it hinders the coanda effect much. I will do some real measurements of the actual flow to see the difference. I am mostly printing ABS by the way :-) I have a friend that starts to be quite experienced with PETG and that seems to be a very interesting material indeed...
You are far from a idiot, and anyone who calls you one is just a troll looking for a rise, ive watched most of your video and you can put your hand to anything you touch, not many are gifted with those skills, look forward to future projects.
Agreed! This is the way a community should work...
@@BjornErikLarsen I've pretty much stopped using ABS now as PETG is easier to print and, other than for small detail parts, gets much closer to ABS than PLA. It's definitely worth playing with and having a shot. Where I do still need the properties of ABS, I now use ASA. It suffers from less shrinkage, but you get the same strength and heat resistance. I used to use ABS a lot, but once I sold my enclosed printers I began looking for alternatives. Between PETG and ASA, I have most bases covered. I tend only to use PLA for things that need to look good or for Christmas presents! Anyhow, I'm sure you'll have this all in hand, but just wanted to mention those thoughts in case they might be of help. All the best!
Great video, I was looking longingly at the water in your damn, a quick dip right now is what I need
I'd suggest do away with the screws to fasten the filters. Too fiddly and too many parts. Instead, replace the bars they are resting on with i-bars (similar to an i-beam), then the filters can all insert from the bottom and slide up into place. All the filters would be held in place with a single bar at the bottom, secured on the two sides. You could even have the locking bar pivot upwards to release the filters for easy replacement/cleaning (think of the game "connect four" and how you release the counters when the game is over).
I was thinking some dove tails one male and female each side they would then key to each other in any orientation you just need to fix some top or side bars to hold it all together.
I just paused the vid to come and suggest pretty well the same thing... :) would provide a much smoother surface too
@@jayt9882 On the big ones the upstream end has a t-bar that slides below the accellerator positioning the leading wires and preventing uplift.
☝️💪🙃
If you slide them in from the top with an lip at the lower end, the top can be clamped under the accelerator bar. Makes removal for cleaning easier.
Floating debris barrier. Google that for ideas and an alteration of these may keep debris from your outlet. Water flows under the barrier to the area for your outlet. Debris is captured by the barrier on the pond surface. With a much larger area under the surface of the water than the outlet area in the wall, the flow is much slower than at your outlet in the wall so debris is not drawn down under the surface and into the outlet. This could be a plank across the pond. It could be sheet metal that has a few inches above the water and more "height" below the water and forms a semicircle around your water outlet. It could be a floating boom like you see if you google "floating debris barrier". I believe this would stop most of the debris and only occasionally need cleaning.
Give it some thought. Lets have your community debunk or add to this idea. It might have value.
I think that would work. I know they use a simple debris barrier made of linked logs near a dam next to a canal lock where i live and it seems to do the job.
Shoot u may as well do an entire cover that even goes down below the depth it freezes and insulate it. Then theres no chance of floating debris or things falling on it and if it flows throughout the winter it would prevent icing
A semicircle arc of steel rod, mounted on the top of the weir, with vertical rods, about 10cm apart, about 1/2metre from the spillway. Will need regular clearing whatever you do.
The leading and trailing edges should have "Z" joint so they lock together. Only would need two screws per tile or even LESS!! You you could probably even skip tiles and have some tiles that don't have any drill holes at all. Gravity and water pressure would be your friend. Waffling would be the only issue with extremely high water flow but I doubt that that would happen. The foil will pressure the plates down as well.
Yep, beat me to it.
great idea, and with less fasteners, that is more surface area for water collection, this version looks amazing, but imagine if there were no screws and went into a frame and all that water running down those screw pieces was going in and not being lost. Really excited to see how this evolves, Kris has done an amazing job finding his 3D printer friend....does the printer friend have a youtube channel by any chance?
Thanks Kris, calm meditative videos.
Chris this is one of those projects that I just can't wait to see the next episode, looking forward to seeing the results!👍🇬🇧
Whenever I need to drill several holes that needs to be exactly positioned I make a template out of plywood to guide the drill.
or put tape on and mark with a pen...
Nah, you put the things your going to mount on the template and drill the holes in it. The holes gets perfectly positioned and no measuring needed..
Mats Gustavsson don’t need to measure or make a reusable plywood template to just lay some tape down and mark it with a pen through your mounting holes.... common sense.
Calm down gentlemen, both of the proposed ways do work. And each of them has its place in the work.
Just lovely seeing what you are others are developing!
Simple and smart hydro for all!
Great work Kris
I remember when you first started your channel, and I find it amazing how much you have learned and grown in knowledge!
I really like your videos on your hydro system and your continuous improvements to the system. For what is worth, I'd like to make a suggestion. On the upstream side of your spillway, add a semi circle of 1/2 ' wire screening that would be positioned above the spillway and curve around to either side of your spillway and fasten to your dam. It would be about as high as the dam and reach the bottom of the water depth. This would keep any floating debris from ever reaching your spillway and yet would not interfere with the water flow, as the water would still flow below the debris buildup on the surface and over your spillway. I hope you understand my explanation.
Such a large amount of information coming from all sides! Very cool that someone wants to work with you to help improve your system. I wish you the best of luck on all that! Cheers!!
The water diverter plates are brilliant. Thank you so much for breaking down how your system works. I'm sharing with my son. He'd love this.
Great video. I am a middle school technology teacher and love to be able to show my students useful collaboration with technology.
This is the first application that I have seen the use of an Allen Wrench outside it being included with an item I have ordered. Good job in showing the Allen does have a multiple use! Thanks!
I think it could be better to not use screws anyway, maybe just built a frame around it with a rail where you can slide them in and fix them with the top and bottom screws on the frame. 🤔
Could send you a quick drawing if you want?
PS: Man, because of that kind of stuff i love the internet: When people reach out and just do good stuff!
Yeah thats a nice idea. If they all interlocked just the edges held down would be fine. Thanks
@@KrisHarbour I would of said the same as then if you need to do anything you dont need to refit the bolts while its in place and try to fit them when its raining wont be fun.. but no reason why you cant do 2 files so you can choose to print with or without holes in the final design..
@@KrisHarbour
Change the 3d print design. Put square pegs protruding from the mesh "cells" corners. Then make a frame bracket like Wieheisstder said, with square holes cut in it, and interlock all mesh "cells" together perfectly, no screws, nothing sticking out the top.
Fix the frame bracket to the body of the intake thing, you have plenty attachment points.
Some sort of retention frame with neo magnets for tool less removal?
@@AdamKalbasz thats called over engineering, bruh.
for the V shape you could also have an extra part that you secure with the same bolts that hold these things down.
that way you can also play around easily with different shapes and sizes without always printing new plates.
I am really enjoying this series of videos, thanks for sharing the process. :)
Dear Kris Harbour.
👍👌👏 Sir, again I learned something new from you respectively your channel (never heard of Coanda before). Actually I wanted to suggest better/different mounting options but some viewers already did. 2) Good to see that your back seems better. 3) The ads before this video was about "barkskin". I think that's a kind of funny coincidence. 😁
Thanks a lot for making teaching recording editing uploading and sharing.
Best regards luck and health.
You're UA-cam videos are really nice all of watching how well you do this whole hydro electricity. I was sharing the best way for you to get the bolts in place without too many difficults of rapping it down is welding those bolts in place so all you have to do is add the screws in and I'm tightening it down on its own
Love love love the hydro update vids!! Keep them come Kris!
GENIUS !! Great job. Please keep it up. I'm hoping to fit a micro hydro at my brothers house soon. I really value your efforts and input.
John S
Great, thanks for the update, really interesting and great explanations. Can't wait for the improvements and next video.
Yes agreed with Elgarl, do away with the screws great suggestion. A great channel and very informative as well as educational.
Those sleepers are treated!! :)
Watched with great care, you got my brain going, so jumped on here just like the masses to comment, i think, you should, i would!! is great to see your channel subs commenting like AVE's :) I think uncle Bumble F*** should get on his CNC machine and help you out too.
You got some great ideas posted so i wont add mine as it will put them all to shame 🙊 (NOT) one observation, i think the higher water flow in the winter will flex the fins to much, maybe think of a support on the inside of each panel. Stay safe buddy, hi to Dot x
Finally someone was “brave” enough to mention the treated sleepers. 🤣😂🤣😂
Hopefully we get to see you back helping Kris once again Gaz. The two of you worked very well together.
Thanks for posting and sharing. Really impressed with this hydro electric set up. Thanks
It's good to know that the research of my great relative it's been used in such different applications although the goal was to build the world's first jet engine .
Which resulted in the flight of the first jet plane in the world that my relative built and piloted in France in 1910 .
the tweaking/engineering/improvement makes great content.. your other vids too though.
21:11 Suggestion for better self cleaning in low flow:
Consider there are 3 "channels" on the grill: left, center and right.
If you put some light flow restriction just above the left and middle channel, it will concentrate the flow on the right channel.
To do do so, just put a 1cm thick plank on 2/3 length on your red wood channel.
You can put another 1cm thick plank on the left side side as well.
You now have a ultra low flow concentrated on the right channel.
If the flow is slightly more, it will go on the right + middle channel.
Finally, if the flow is even higher, the 3 channels will be irrigated.
Let me know if it's to confusing! Hope it will make your cleaning easier.
Alex from Montréal, Canada
literally just checked your feed. new hydro stuff, awesome
Same here😂
lol,.... I read 'feet' instead of feed. :)
to each his own lol
Absolutely Awesome, Thank You for sharing.
i think this fellow knows what he is doing!
Awesome Kris, great video! 👍👍👍💯💯💯
Maybe just have a frame to go over the top of the tiles to hold them down without any bolts into the tiles. Or, once the final design is complete, just glue the tiles together into one big tile.
Amazing, probably Coanda never thought about his work being used in this manner. This is cool.
Looking forward to seeing the STLs for these and seeing if I can help produce these for people like yourselves!
What a superbly interesting video showing a genius at work. Brilliant.
I always wondered what you were talking about when you mentioned coanda screens in previous videos. Brilliant idea though and great it potentially will be open source. Thanks for the content buddy! 😁
Kris, just an idea,. have you thought about creating a private outdoor bath with your waterfall? Ok, so maybe heating the water would be all but impossible, (so, no hot-water bath like a Japanese Onsen), but if you like cold-water baths, it'd be a great idea IMHO.
Some careful and creative stone landscaping, pools, a small roof perhaps, walkways, retaining walls, a clean and flat clothing storage area, a roofed, dry, rest/changing area (for when it's raining and you're wanting to get warm n dry or read a book etc) and maybe even a small, sun-powered, sauna room or something. :)
It would be a lovely spot for sure and i can picture what you mean and it would be lovely. i just dont think that the amount of time you could spend in there due to the cold would make it worth it. it would be a plunge and that about it. Its very cold water even in the summer. The summer flow is mostly spring water from about a mile away so it is cold!
@@KrisHarbour You can gain some warmth by routing the water underground through pipes. There should be a few videos on youtube how they do it for their pond.
I don't usually comment, but this was a really interesting video. Thanks Kris
Great solution, perfect for this installation !
The coanda filters self-clean with excess water flow and with the dirt that accumulates and in turn pushes down the previous one, they recommend having positive and not negative pressure with suction, usually they use a much larger diameter for a few meters of the water pipe in order to slow down the flow to a minimum in the water intake, I understand that you must try to use all the water possible and at the same time maintain a good level in the tank in order to have an excellent level and pressure and not losing water is not easy but as a first result it seems excellent to me, something always stops, in some plants with coanda filters they have problems with sunlight and algae and moss that accumulates and obstructs the slits.
Good job !
Ciao
Find it very interesting, how simple it is if you just understand and I believe you explain it very well, Thank you!!!
I love reading the comments section of these videos. So many fantastic and helpful hints.
Totally agree! It is a lot of smart and experienced folks out there :-)
I think a printed flow plate the same width of each tile could serve several purposes. It would match up perfectly with tiles, condition the water for laminar flow, could have the water diversion angles built in, all while being easy to replicate and expandable just like the tiles. I would assemble the tiles from the bottom up. This would be easier to assemble, and let you reduce the number of bolts on every tile, as the printed flow plates could be installed last and secure everything in place. Love this idea. This is exactly what 3d printing is for. I hope you guys can get a good product figured out, and maybe even turn this into a business.
Super interesting video Kris. Thanks for the content :)
BRILLIANT JOB.
Very impressive
You are such an inspiration to me!!
not checked through if someone has already suggested, but maybe having lap profiles on the sides of the plates, could reduce your 2x 30mm “water slides” down the middle to say 15mm? the plates sized as they are then wouldn’t fit the square so would be bigger, slightly stronger wedges...
my other first thought was instead of individual plates that you can bolt together (handy for making universal) your best bet would be a full 1 piece plate, would have stronger wedges as could be bigger and then would reduce to only 4/6 countersunk fixings around the outside edge, and would completely stop the “water slides” and the bolt profiles catching things...
that’s if a plate that size could be printed, and would be bespoke and tailored not suitable for a universal download.
love how you just smash em on and road test them on your home system! good lad! always an interesting watch kris, enjoy your weekend mate
Well done!!!
Very cool, I could see the material changed to stainless triangular rods to span the whole width. Maybe even a variable angle system that can increase and decrease depending on water volume and cleaning need.
I'm no expert but a one piece filter would save you a lot of water. Nice job 👏
Looks promising.
I noticed you still had some issues with leaves catching on your intake even after you installed the coanda screen. In order to prevent most leaves getting to the outlet Could I suggest that you install some sort of floating barrage in the pond across the width of the outlet and about 1m from the dam wall to intercept any floating debris whilst still allowing "clear" water to flow under the barrage and over the weir. This barrage could be shaped to direct any floating debris towards the overflow notch and presumably during periods of high flow when the overflow was activated, the floating leaves caught behind the barrage would go over the overflow. If the idea of a floating barrage doesn't suit then a fixed barrage, again in front of the outlet weir, braced of the dam wall, could work assuming the level of the top of the barrage was set say 30mm or so above the level of the weir, and the underside set say 100mm below the weir level. Then during low or medium flow the leaves would be caught behind the barrage and clear water would flow under it. During high flow when the pond levels were up, the barrage would be overtopped and any leaves caught would flow over the weir, presumably being swept away by the high flow going over the weir at that time. - Just some thoughts with my Civil Engineer hat on!
Yes dams in my area use a string of logs to block debri going into the intakes.
Nice one! You could add like something to cover the screws with a shape like (^) to make the water go to the sides! Great project! Keep going
Hi Chris my man not sure if u’ll see this, I’ve never messaged before I’ve only subscribed to a few channels in my lifetime on you tube. I have watched almost everything you have uploaded sadly starting from the end. I then figured out how to watch from the beginning. I’ve watched almost every video and can honestly say there’s a few things I could of helped you with, information wise. You have being doing this 5 years now so I’m sure you’ve figured things out. Tell Dot and the cat I said hi. I’d love to come down one weekend and give you a hand. Myself and my missus was in Wales 2 years ago to watch Anthony Joshua fight. Keep me in mind Chris love your channels. I’ve got a lot of ideas for you so get in touch mate cheers. My kids and missus always ask what you watching and they get drawn in.
FINALLY ive been waiting for another vid
Looks Great, Nice concept. be cool to see a secondary manifold to catch the run off, from the screens. excellent. work.
If you incorporate the half joint rebate on the top rail of each screen to fit under the top trim as you suggested and also put a corresponding half lap rebate on the bottom rail for the bottom row of screens to slip under you could probably reduce the number of fixings required by 50%. I would suggest that the single side rail fixing be positioned 1/3rd of the screen height up from the bottom rail as your starter for ten. Looking forward to developments. Keep up the excellent videos and keep safe.
Love the Ave tee! Really skucum!
Mega job, screens are a weak link in many systems, great to see some open source research being done. Cant wait to implement these in my intake. Please publish a short update video Kris, when you have some decent flow..
Good you got a brush to clean the water grate. 👍🇨🇦
Very interesting, I have a pretty large 3D printer up to 610 MM square. I look forward to seeing the files available, that would be fun to play with..
brilliant! 👍
Totally think it's great!
A couple of “V” s inverted above the top screws could be superglued on to your existing ones to see the effect maybe 5mm to deflect the water past screw heads as a test but looks good so far we’ll done guys and thanks for the update
Maybe a sight glass on the side for inspection? Great work mate with everything. God bless ya
The overlap that you mentioned for the upper tile to hold the lower tile could also be your way of holding the upper tile under the acceleration plate.
You could go one step further and add the same Z flange to the sides so the right tile overlaps the one to its left (or vice versa) and conceivably only use one screw to hold each tile in place.
Great timing. I was just watching your dam video.
Hey Chris. I know you said you lived in London but my wife thinks that your accent is Sheffield.
Really? i have never even been to Sheffield. I grew up in Surrey
Kris Harbour Natural Building I’ll tell her.
If you asked him to redesign it so that it could be adjusted to custom length and width, that would be awesome. Also, then he could adjust it to remove the supports that are used to bolt the plates on top, and add the supports under the slats by using a triangle shape. Awesome initial design, can't wait to see the next version too
I will make a parameterized model that can be tweaked with many parameters in case you have a larger printer that can print larger tiles. Both the angle and number of wedges, width can be configured before printing it... But this will be done when the reasearch has ended up with a design we are satisfied with...
@@BjornErikLarsen - Can't wait to see the end results. Very cool stuff
11:10 - When I saw this part of the video I thought it would be really beneficial to have a removable steel frame (for the tiles) you could slot in/out, whenever you needed to, for changing or cleaning tiles. The side/bottom edges could use steel or aluminium L-section and you could secure the frame on the top side with bolts, that would bolt into welded nuts to go under the lip of the section of white pipe. I don't know whether you've already considered that and chose your current plan but being able to slot in & slot out a tile frame would've been my plan. Slots and grooves for the tiles would be a good plan too to ensure they fitted perfectly.
That is a very good idea!
That water looked so cool it looked like it was standing still
BJORN!!!!!!
To get hole to line up, Use sharp punch to make a mark for the drill to find the centre of the hole
Realy interesting project. To get the water to spread out more uniformly over the grates ( it seems that only 60% of the screens are covered with water) you could have vertical vanes (mounted on the wood) guiding the water, maby even 2 thicker ones where the screens are next to eachother. Maby a better ide is to have the screens tilted to the sides (the middle one the highest). A tip for drills and taps, use Cobalt HSSCo/HSSE 5 or 8 % drills and taps, will make your drilling and tapping muck easier. For cutting oil you can use Castor oil.
When drilling use fair amount of downforce and low rpms, high rpms and low force will produce heat and burn your bit even if it is HSSCo bits.
One thing you should try is replacing the flat surface of the louvered screen with one that is arched. So instead of the water sliding down a flat surface over and through arched louvers the fluid will travel over an rounded plane and through the arched louvers. Thats if you want to apply what may possibly add to the coanda effect you are trying to benefit from. Also if you want to learn more about this look up Kyle Engineers’ channel. Specifically the video about rear diffusers and pay close attention to his comments about maximum/minimum degrees of slope, angle, and curves. Also if you’re having problems with debris getting stuck in the louvers when the flow is at a minimum i would try replacing the louvers with the original screen but i would bend it to round the surface to see whether or not debris will build up over an arched surface. Im assuming the screen would mitigate the problem as the holes are offset. But it would need testing …
Been waiting for this one!! Great video and very interesting... I think a removable coanada frame would be better. A lip on the centre tiles so you can overlap and use 1 screw for 2 tiles... You attach the tiles and then install the frame... a suggestion ;)
Look forward to future design improvements, like reduce water loss on the parts that doesn't have the grill, and reduced bolts needed to fix it down,
Personally i thing a complete design for the top, including the water speed ramp could be in the design, looks good for the start though.
Your system looks like a compact sieve i use to use for my natural pool.
Great to see this, I would suggest that one big screen will let more water through. The two new support bars and the frame round each filter will restrict the flow of water.
Yeah but the trouble is most 3d printers cant print stuff that size so the design is taking that in to acount and making these able to accommodate most 3d printers and most intakes by being modular.
You could put a screen underneath the tiles to catch any small bits of grass that make it through.
Put the screen over the slats. The water that does not immediately go through the slats will push up and slightly back through the screen (provided there is a minuscule gap between them) and push the garbage down and off.
Rivnuts could be your friend here Kris, require a larger hole than the intended fixing & gives a strong threaded attachment for whatever... El cheapo kits from China can have mandrels that can be a bit fragile in the smaller sizes, but M5/M6 should be adequate for your purposes.. HIH.
Depending on the type of plastic you could glue or solvent weld them together to save bolts and holes
Yore may be able to change to counter-sunk self tappers or use a glue or pop rivets this could replace the bolts . and thanks for the video Kris
Love the shirt. Shout out to AvE!
You need a stand pipe in the water about 2 inches below the water surface with a screen dome over the top. This will give you so much more head pressure, and allow leaves to be washed off when the dam overflows.
The 3d printed screens are good for proof of concept. They obviously need a few tweaks, but once sorted should be a very good, cost effective alternative to the currently available ones.
Remove the holes completely from the 3d parts and use some type of clamping T bar to hold them in place. Looks great.
I think the tiles could be designed to fit together like puzzle pieces. The screw mounts could be deleted. In the middle sections. The top could be improved by instetting the top race. The whole screen could be held in by a bar on the bottom.
neat device. If You put a strip of SS down the joints welded to a bottom stop. You could install them with top capture only and not need the bolts at all.
Kris maybe get the tiles designed so they interlock? That way you won’t lose as much surface to the frames around each screen. Same sort of concept as the plastic blocks used to build up 18650 cell packs. Looking good though. 👍🏻
This setup is mainly to determine the best angle to set the 'blades' for maximum efficiency.
Bjorn has commented above that when they have determined the best configuration, the screen will be printed in one piece.
jaygee I’m guessing Bjorn has a massive printer then. 👍
@@FarmsVilla It will still be small tiles so we will not change the size of them. The tiles today consist of 24 parts and 4 x 3mm screws so reducing that to one part will simplify quite a bit... :-) There will still be 3 X 2 tiles so making a interlock system will make Kris happy by avoiding the mounting bolts :-)
Bjorn Erik Larsen it looks like you guys have got all the bases covered. 👍😁
@@FarmsVilla Yes, we have got a lot of very nice feedback in these comments :-)
Chris, if you would like to stop all the floating stuff like sticks and leaves from going down your sluice, I think you could do it by using the same principle as oil spill booms that float on the surface. I would suggest using something like a 4x2 timber fitted on end, going across and fixed on both sides of your pond, so nothing can get past the ends, as its a constant hight of water, fitted half in and half out of it, if that makes sense. I bet you could even fit the timber at as close to 45 DEGs across the water flow direction as you can, and all it catches would end up on the downstream end on one bank or other as you desire. Just a thought which may be worth a try. Good luck.
If you are wanting countersunk screw holes I suggest allowing the material to be thicker, like raising your whole surface to allow thicker materials.
I learned the hard way... andI only ever use Cobalt alloy drill bits on stainless
You should build a frame that the tiles slide into. Then you can use 4 bolts to attach the frame on to the top of the box, making it east to remove to clean or work on. By making the tiles able to slide into the frame you will no longer have drill holes. This will also reduce cracking due to expansion and contraction with weather change.
Kris, you mention sludge in the bottom of the intake. You might consider adding 2x1" pipe fittings/plugs under the height of your intake tube for clean out in each corner. That way you just unscrew the plug and let it wash out.
Make half moon covers for the bolt heads, to direct everything away back to the plates. Easy fix. Awaiting the next video..
There are special drill bits for ss, usually cobalt steel. They are expensive but will last you long if you keep it for ss only. Normal hss bits aren't up to the task and they can introduce galvanic impurities into the steel and cause it to corrode faster.
Thanks as ever for sharing your knowledge and wisdom, you are a wealth of information and are taking a lot of guesswork out of my hydro build.
Any more information on Bjorn and weather his plans are available... Happy to make a donation.