diy solar

diy solar

Custom Bus Bars From Copper Flat Bar

I dont really consider it a problem :) I just used calipers to measure the height differences and at some point, I will take the router and machine a pocket in the 3/4" plywood for the battery protects, the fuses will sit on the board and will just cut some blocks on the table saw to insert under the shunt. The top switch will just sit suspended and a block under one end of other switch. Its super simple, just may need a little trial and error to get it perfect.
 
HRTKD said:
@noenegdod, it looks like you ran into the same problem I have. The mounting surface heights are frequently different. I like the bus bars as shims under the shunt. (y)

I like how closely the copper bus bars allow the devices to be located, but height differences require a bit more effort and materials. I'm going to start with 1/4" plywood. I think I have some 1/8" plywood around here somewhere, but that stuff is kind of worthless.

I was thinking about how to put together strain relief for the cables. I might raid my kids old Lego sets. It doesn't get much more modular than Legos.
Click to expand...
BEP solved that problem with their Pro Electrical Installer System.

Pro Electrical Installer System
 
Another source for copper bars is onlinemetals.com I used their nickel plated copper for buss bars 1/4” x1” - it worked out well.
 
Use split point drill bits , they don't walk around and drill easier and less heat . Heat will cause a lot of burrs .
www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com
I have used these for years and they are cheaper than the rest , and drill faster. When Burton Snow Boards first came out in the early 90's , I machined the aluminum angle plate , all of them. I drilled over 54K worth of holes with 1 cobalt screw machine drill bit (@ $1.75 at that time ).

I recommend using a c clamp or vise to hold down the part , because when you break thru, it usually will grab . Using a sacrificial piece of metal (not the drill table) underneath will eliminate the grabbing and less burrs. Use a fresh spot for each hole . I have been at this since 1977.
 
Any drill bit will wander, some more than others, especially in something as ductile as copper. Center cut end mills, as previously mentioned, are the perfect solution. Failing that, start the hole with a center drill or spot drill. Their whole point is no wandering. Then drill thru with any kind of standard bit.
 
Paul_R said:
Any drill bit will wander, some more than others, especially in something as ductile as copper. Center cut end mills, as previously mentioned, are the perfect solution. Failing that, start the hole with a center drill or spot drill. Their whole point is no wandering. Then drill thru with any kind of very sharp standard bit.
Click to expand...
Added "very sharp"
 
Paul_R said:
Any drill bit will wander, some more than others, especially in something as ductile as copper. Center cut end mills, as previously mentioned, are the perfect solution. Failing that, start the hole with a center drill or spot drill. Their whole point is no wandering. Then drill thru with any kind of standard bit.
Click to expand...
Most of the people out there do not have a Bridgeport mill to use a 1/4 end mill to drill holes . Drill presses wobble a lot and need a vise. And apparently you haven't used a split point drill bit. I can drill 1/4 holes, 1.5" deep in aluminum at 4000rpm at 100." per min an be within .0005" on size and location with a split point drill and get 50k holes life and still be sharp when i am done with the job at less at a couple for the drill bit.
I have been drilling holes in a machine shop for all most half a century.
 
JimJr said:
Most of the people out there do not have a Bridgeport mill to use a 1/4 end mill to drill holes . Drill presses wobble a lot and need a vise. And apparently you haven't used a split point drill bit. I can drill 1/4 holes, 1.5" deep in aluminum at 4000rpm at 100." per min an be within .0005" on size and location with a split point drill and get 50k holes life and still be sharp when i am done with the job at less at a couple for the drill bit.
I have been drilling holes in a machine shop for all most half a century.
Click to expand...
It sounds like you're a machinist, I was too in another life long ago ?

For the purpose of this discussion, a center cut end mill will work just fine in a decent drill press and vise. I don't think anybody's after .0005" accuracy. For me it's all about not having to deal with big honking burrs. I may have to go out and buy some split point drills now though...dammit!
 
JimJr said:
Most of the people out there do not have a Bridgeport mill to use a 1/4 end mill to drill holes . Drill presses wobble a lot and need a vise. And apparently you haven't used a split point drill bit. I can drill 1/4 holes, 1.5" deep in aluminum at 4000rpm at 100." per min an be within .0005" on size and location with a split point drill and get 50k holes life and still be sharp when i am done with the job at less at a couple for the drill bit.
I have been drilling holes in a machine shop for all most half a century.
Click to expand...
Most dont have a bridgeport mill, a continuous supply of coolant or the skills to resharpen split pont drill bits either. ;)
 
I worked for period of time as a planner scheduler in a machine shop. Have nothing but admiration for the skills needed to operate this equipment.
 
I put masking tape on my 3/16" copper bar stock ---a lot easier to mark my holes for layout -- dimpled with a center punch -- then I made a better center point with an 1/8" bit (not making a hole) -- went directly to 11/32" for my holes --- this particular time I used a Ryobi 12v drill with the bar clamped down on a wood bench --drilled like butter ---- For my first battery I used some 1/4" brass stock I had --Drilled the holes in the same method < but with my drill press ---- the 12v hand drill was much easier -- I'm told brass is harder to drill though
 
I spent the day at the storage lot yesterday and made good progress. The new step drill bits did a nice job. A quick swipe with sandpaper cleaned up the contact area nicely.

I hauled my drill press and chop saw to the storage lot and that worked out really well, but that drill press is really heavy even though it's a benchtop model.

In the picture below, anything that is bright copper is new, the common bus bars (big shiny things) are also new. None of the devices are secured down, covers aren't on and the cable strain relief isn't in place yet either. All this in in preparation of wiring up my new inverter which calls for two cables on each DC leg (pos/neg), four total. I think this new setup is going to be more efficient. I have been stacking cable lugs on posts and I have to wonder if my batteries weren't as well balanced as they could be for charge and discharge. I'm referring mainly to the lugs on the shunt and the Class T fuse.

Some adjustments still need to be made. It's a little rough. I was out of time. It was dark, my flashlight batteries needed a charge and it was 35° F.

I am not impressed with the dinky little M6 studs on the Victron Battery Protect 65.

@noenegdod, the lowest speed on my drill press is 850 rpm. That's higher than I thought.


1643045760505.png
 
Alloy said:
I drill copper by hand with an electric drill starting with a mechanical center punch.
View attachment 79307

Next is a 5/32"drill bit for pilot holes. All my drill bits are good quality 118° split point. I'll use any cutting oil that's around.

Step drilling 1/6" at a time keeps bits from getting plugged and breaking.

If the bar has hard wood/plastic (ViseGrip) clamped to it I'll drill thorough if not I stop 1/2 way and come in from the other side but that doesn't work as wall as the backing.

A counter sink removes the burr and make the bars look pro.

Most important is keeping the drill perpendicular to the surface.

That Diablo blade looks like it has a positive (a line along the face of the tooth crosses in front of the center hole) rake. A true non ferrous blade has a zero or a negative rake like this one has. Also note the backing for the teeth is shorter and much stronger.

View attachment 79309

***Be very very very careful cutting copper with a saw blade. I've seen people screw up and rip 10-15 teeth off a blade along with the backing for the teeth. I've also seen the motor come off the rails on compound saws. Cut through the smallest dimension. Make sure it is double/tripple clamped.

I like to used the lesser of 2 evils which is a Walter 1/16" zip cut wheel on a grinder but the copper gets scorching hot. I've seen people that don't know how to use a zip wheel destroy it by side loading or twisting it and have piecs of the disc embed in a wall 20' away.

This is the proper position to for a grinder when zip cutting. Most important is to always have it pulling away from you an




View attachment 79299
Click to expand...
Wow. That’s nice. (Last pic)
 
Last edited:
HRTKD said:
I spent the day at the storage lot yesterday and made good progress. The new step drill bits did a nice job. A quick swipe with sandpaper cleaned up the contact area nicely.

I hauled my drill press and chop saw to the storage lot and that worked out really well, but that drill press is really heavy even though it's a benchtop model.

In the picture below, anything that is bright copper is new, the common bus bars (big shiny things) are also new. None of the devices are secured down, covers aren't on and the cable strain relief isn't in place yet either. All this in in preparation of wiring up my new inverter which calls for two cables on each DC leg (pos/neg), four total. I think this new setup is going to be more efficient. I have been stacking cable lugs on posts and I have to wonder if my batteries weren't as well balanced as they could be for charge and discharge. I'm referring mainly to the lugs on the shunt and the Class T fuse.

Some adjustments still need to be made. It's a little rough. I was out of time. It was dark, my flashlight batteries needed a charge and it was 35° F.

I am not impressed with the dinky little M6 studs on the Victron Battery Protect 65.

@noenegdod, the lowest speed on my drill press is 850 rpm. That's higher than I thought.


View attachment 81069
Click to expand...
That looks good!

I found that the step drills seem to do a good job of cleaning up burs like a counter sink does.

850 RPM is still a pretty good clip. Im impressed you are able to do such a good job. Slowest speed on mine is 280 (max 3000) and I drill everything copper at that speed now. Just have to be super careful with small dia bits as they tend to grab and break.

Does your drill press have an idler pulley or just a primary and secondary? Mine has an idler and 2 belts which might be why it is so much slower.
 
noenegdod said:
That looks good!

I found that the step drills seem to do a good job of cleaning up burs like a counter sink does.

850 RPM is still a pretty good clip. Im impressed you are able to do such a good job. Slowest speed on mine is 280 (max 3000) and I drill everything copper at that speed now. Just have to be super careful with small dia bits as they tend to grab and break.

Does your drill press have an idler pulley or just a primary and secondary? Mine has an idler and 2 belts which might be why it is so much slower.
Click to expand...

It was dark and perhaps I didn't have the right reading/safety glasses on. 820 turned out to be 620 once I got a look at it in daylight.
nerd.gif


No idler pully. Just the primary pulley on the motor and the secondary on the spindle. It's a 25 year old Delta benchtop model that I've had since it was new. I checked to make sure the table was square to the bit in two directions and it was right on the money.
 
620 makes me feel a little better :). I was wondering what the hell I was doing wrong if you could pull it off at 820 and I certainly was not doing that well at 800.
 
Sanding around each of your bolt holes is probably a good idea for connectivity. I don't know about that flat bar but I know copper pipe has a "clear coat" on it to prevent it from turning green. I built a copper fountain for my KOI pond thinking it would turn a nice green patina but the coating stopped that until sanded off. One of my only youtube videos LOL.
 
The Dish Doc said:
Sanding around each of your bolt holes is probably a good idea for connectivity. I don't know about that flat bar but I know copper pipe has a "clear coat" on it to prevent it from turning green. I built a copper fountain for my KOI pond thinking it would turn a nice green patina but the coating stopped that until sanded off. One of my only youtube videos LOL.
Click to expand...

If there is a clear coat on the flat bar, it's certainly gone after I dress the contact surface with sandpaper. I had considered treating the bus bars once there were in place with a quick spray of polyurethane to deter oxidation. But I'm going to let it go for now and see how it ages.
 
I’m curious about the arc interruption capacity of the air gap between bus bars. Some of those look pretty close.

If/when a moth lands and bridges the gap, I wonder if there could be a problem? That is, how much space between bus bars would be needed at a given voltage?A1AC2F28-AEF9-4DBE-BB7F-AB8AEB58CF8E.jpeg
 
Bluedog225 said:
I’m curious about the arc interruption capacity of the air gap between bus bars. Some of those look pretty close.

If/when a moth lands and bridges the gap, I wonder if there could be a problem? That is, how much space between bus bars would be needed at a given voltage?View attachment 82327
Click to expand...

I had the same concern and asked that question here: https://diysolarforum.com/threads/how-close-can-bare-copper-bus-bars-be-12v.30555/

Not so much about a moth but if the battery protects were to open while the winches that are down stream from the battery protects were operating, would 12v jump that gap. Just to be clear, the two bars that are really close are both positive. That thread exposed a few other issues I had and was able to work out a solution that should address all the issues.

I am also thinking about greasing up the bars and the battery protect and extruding some silicone between them to absolutely prevent any chance of any kind of unwanted current between the two bars.
 
You must log in or register to reply here.

Similar threads

M
Two lithium, connected to bus bar
Replies
14
Views
362
HRTKD
HRTKD
M
Copper strip bus
Replies
6
Views
528
740GLE
7
K
DIY bus bars for 2p8s battery bank
Replies
5
Views
507
littleharbor2
L
L
Preventing water ingress through outside wall holes (timber frame construction).
Replies
7
Views
192
Luk88
L
M
Stud to stud connection
Replies
5
Views
189
ThaiTaffy
ThaiTaffy

diy solar

diy solar
Back
Top