control box / enclosures - some tips for anyone considering it

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Walker

I use secondaries. :p
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I'm building a HERMS system and thought I would share some thoughts. I took my time and was very patient while searching for good deals and one day an offer too good to refuse presented itself on ebay. I picked up a new-in-box Weigmann brand 10"x12"x5" NEMA 4X steel enclosure (with an inside panel and hinged door) for $35 shipped. This thing sells for no less than $130 online.

I was very pleased with myself for having scored such a good enclosure for such a good price.

But.......

Now I have to work with that thing, and the steel is 1/8" thick. I don't know if you've ever spent time cutting through 1/8" thick steel, but it ain't exactly easy or quick with common tools. I can pretty easily DRILL through it (stepping up a little at a time). A 1/2" hole through it takes just a couple minutes. Easy as pie.

Cutting big 2 1/8" holes for my output receptacles was a chore. Lots of time, pressure, cutting oil, and a big hole saw. I had to take a few breaks to let my drill cool off, but I got it done. While doing this, I started to get pretty damn concerned about what lay ahead for me.

Cutting square or rectanglular holes in that f*cker is not fun. The PID needs a square hole, and it has to be a pretty clean one, so brute force and sloppy lines is not an option. A little finesse is in order. I'll get it done because I really have few options, but I am starting to reconsider all of the switches I bought that need to be installed. They are all rectangular in shape with a very small lip around the front to keep them from going all the way through the panel holes, but the lips on them are very very very small.

This means I have a good bit more straight-line cutting, with very clean and precise lines.

I am seriously considering cutting my losses on the switches re-ordering round ones that I can just install in drilled holes. This will save me hours of work and be less prone to error.

So... sorry for being long winded... but if you are considering building a control box for a HERMS or RIMS or just a box for the controls of an electric kettle, think about what you are buying, how you will cut and or drill it, and what you will have to actually install through the walls of the thing.

If my box were made of plastic, I think I would already be done with everything.
 
Forgot to add... one thing I am considering is cutting rough holes in the thing and covering them up with blank face plates from the hardware store. Those face plates will be much easier to do precision work on so that I can mount switches and the PID and whatnot.

I don't really want a bunch of faceplates screwed to the thing, but I absolutely think that I will not be able to do a good job mounting the small rectangular switches directly through the thick steel.
 
Maybe a nibbler would work for cutting the straight lines.

Nibbler.jpg
 
If it makes you feel any better, had the majority of my panel done, but was waiting on some new L6-30 flanged power connectors. I wasn't able to find plugs that fit the ones on my box. Sent it off to powder-coat. Came back real pretty, but the new flanged inlet/outlet are about 1/4" bigger in diameter and don't fit. Now I'm struggling with taking a jig saw to my shiny red panel to make the holes bigger... or trying to track down a 2¼" chassis punch. I feel your pain.
 
Boerderji:

I am (or have been) trying to use a dremel with cutting discs at this point. I have not tried the exact (large) cutting disc you have pictured at the top, but I actually think that this will be TOO big to help me with the switches.

By the time the disc made it through the 1/8" thick steel, it will have cut a line into the metal that is too long.... it would reach past the edges of my switches. I guess i could cut from the inside instead of the outside to get around that ugliness. I will say that using the small cutting discs, the dremel gets REALLY f*cking hot and I have to stop either because of that or because the batter is nearly drained.

I was looking at a dremel cutting tip (a bit, not a disc) that is meant for hardened steel, and might pick one up today and try some practice cuts on the back panel.

I'm also considering removing most of the metal with drill bits and then cutting away the teeth that are left behind with the dremel.
 
Where did you get the switches from? Returnable? The controllers are one thing, but tiny square holes are a bit silly IMO. Do you have any machinist friends? A mill would be handy or maybe look for a square punch...

Those bits are very hard to control without a jig FWIW.
 
I bought the switches from mouser.com. I don't know it they are returnable, but I only have a few of them (costing me a couple of $'s), so it's probably not worth the effort.

I agree that, in retrospect, rectangular switches were probably a bad idea. It was just something I didn't think about when I purchased them (which was really the thing I was trying to get across to others with this thread.... think CAREFULLY about what you are buying, what you have to install it in, and how you will go about doing that.)

No machinist friend for me.
 
I'm am using a dremel. It will eventually get the job done, but it'll take forever.

1/8" is a LOT of steel to cut through.
 
I'll look at the punches, but getting the right size might be a problem.

The switches need a hole about 3/4" by 1/2".

However, it will probably just be cheaper to buy new round switches and drill holes. :D
 
i used this to make holes for 22mm switches on a nema 1 metal enclosure.

http://www.automationdirect.com/adc...cessories_-_Fractional_-a-_Metric_size/109225

mounting the 2 PID's on my enclosure was a pain. i used the metal dremel tool. for power receptacles, i used the 22.5mm punch, and ran 1/2" plastic conduit to outlet boxes mounted on the brew stand. it was much easier than attempting to cut and mount them on the enclosure itself.

p.d.
 
Yeah, I was just looking at some round switches on mouser.com, and they need a 20mm hole. Close enough to 0.75", but I don't have a drill bit that size. So, even if I change over to round switches I am still going to have to buy another tool of some sort.

What I found was faster than just using the dremel for long straight lines was to use the dremel to get a slot cut through the metal, and then insert a hack saw blade through the slot and start cutting with the saw. I did this last night and it went OK. Cutting with the saw was much faster than cutting with the dremel.

I might try to use the same trick tonight, but use my jigsaw instead of a hand-saw. I did not do that last night because I tend to cut less than straight lines with my jigsaw, and the lines I need to cut really REALLY need to be straight.
 
Wouldn't it be easier & cheaper in the long run to just buy a different encloser?
I bought a nice shiny SS paper towel dispenser off Ebay for $10.00 and it has a lock & key on it and it will work great. Just a thought.
 
Perhaps.

For the actual enclosure I bought, it was literally too good of a deal to pass up. I'm going for the upper echelon of safety on this thing and have spent money on internal circuit breakers, contactors instead of just big-ass switches, etc. So, getting something with a NEMA 4X rating was great from that standpoint.

Out of curiosity, what are the dimensions on that $10 box you bought?
 
Walker,

I made my panel from 1/16" aluminum, no comparison to the pain you are feeling, and I had some square holes I needed to be precise like you're talking about. I hesitate to suggest it, because it's pretty obvious, but what I did was cut with the Dremel disc to fit a hacksaw blade like you did, and do the rough cut with the hacksaw. I made my cuts inside my final line, and filed the edge to fit. This is tedious but it works, and you can be very precise this way. I fitted my switches in rectangular openings this way.

I laid out my lines by covering the sheet with magic marker and scratching the lines with a scriber so they were very fine but very visible. After the cutting and filing to fit was done, I washed off the magic marker ink with solvent.
 
I will have to check tonight when I get home & I will post it tomorrow to let you know.
Whats else is nice about it is the slot on the bottom for the paper towel to be pulled from is a rolled edge and makes it nice for the wires to come in & out of. I'm sure mine isn't UL approved but it will work for me.hehe;)
 
Walker,

I made my panel from 1/16" aluminum, no comparison to the pain you are feeling, and I had some square holes I needed to be precise like you're talking about. I hesitate to suggest it, because it's pretty obvious, but what I did was cut with the Dremel disc to fit a hacksaw blade like you did, and do the rough cut with the hacksaw. I made my cuts inside my final line, and filed the edge to fit. This is tedious but it works, and you can be very precise this way. I fitted my switches in rectangular openings this way.

I laid out my lines by covering the sheet with magic marker and scratching the lines with a scriber so they were very fine but very visible. After the cutting and filing to fit was done, I washed off the magic marker ink with solvent.

Yup... sounds exactly like what I was planning to do. I draw all the lines with a sharpie last night, but didn't start cutting anything on the panel's exterior just yet. Wanted to sleep on it before diving in.
 
I will have to check tonight when I get home & I will post it tomorrow to let you know.
Whats else is nice about it is the slot on the bottom for the paper towel to be pulled from is a rolled edge and makes it nice for the wires to come in & out of. I'm sure mine isn't UL approved but it will work for me.hehe;)

Yeah... that's the exact kind of thing I want to avoid. Having a big hole at the bottom of a box that I am feeding 50A/240V into with the intent of using it in an area where I will have water flowing around is not anywhere near the top of my to-do list. :D

I'm going for something a little more bullet proof (or at least splash proof).
 
I am at a loss for words here. as I guess I just don't worry so much as most people. But each to there own. There aint nothing bullet proof. People just need to be careful.
 
Agreed, people need to be careful.... which is exactly what I am doing with this NEMA 4X box. :D

No matter how careful you are, though, accidents happen. I'm trying to minimize the chances of serious damage or harm from me dropping a spraying hose or something like that.
 
Walker, I hate to mention it, but unless ALL of the devices you're cutting into that box are NEMA 4X, you're total panel will be equal to the lowest rating of any individual device - which is most likely NEMA 1.

But back to making your job easier: Go buy a nice, thin piece of Stainless or even Aluminum sheet in the appropriate size, and cut all your devices into that, and mount them. Then just cut one big hole in the cover of the NEMA box, say leaving just a frame of an inch or so. Mount your finish panel to that frame with self-tapping screws, drill all your holes and use the screws and nuts of your choice. You can put weatherstrip tape on the 1" frame, behind the finish panel. That's what I did.
 
Yes I am aware that cutting holes in it derates it, but if you think about it from a different (less official, more practical) point of view, would you not agree that a nema 4x box with a button on it is more splash resistant than a nema 1 box with a button on it?
 
You could hot cut it with a torch, hot cut and anvil. It will go a lot faster that way. :) Or just torch cut it with a 00 tip, or use a plasma cutter. Know anyone with a water jet? :drunk:
 
I just tried to tackle the exact same problem Walker. I found a 16x14x6" hoffman nema 4x for 60$. Had several 22mm holes cut already for my switches which was nice.
I tried to drill a couple 2.125" holes for the twistloc outlets, same as you. Used a bi-metal hole saw on a drill press. It was UGLY. I never made it through before the bit was dead. I gave up on that, and here's a pic of my solution:

https://www.homebrewtalk.com/f51/30-amp-dongles-167904/

7/8" holes instead of 2.125" are so much easier.
I also had to drill those holes for the 120v outlets. They are 1 3/8". I used a titanium step drill bit, and it made it, but after the second hole, several steps on the bit were destroyed. It was a rough experience.
Luckily I have a couple of greenlee punches to make water heater element holes (1.25"). These punches work BEAUTIFULLY. They are far and away the best quality choice for making holes. No filing or anything else required. I used the greenlee for the 120v outlets, then stepped up with the step bit to 1 3/8".

No way in hell am I going to even attempt making any square holes.

BTW as far as tools go, those titanium coated bits you see all over ebay SUCK. Yes I did lube it well. I tried the one that steps to 1 3/8". I killed it, then decided spring for an expensive one from home depot to finish the rest of my holes in kegs and stuff. They aren't even titanium coated, but they are so much stronger. I got the one that steps to 7/8" and it was 35$... but worth it IMO.
 
So I did a test run tonight using a section of the inside panel that needs to be cut out eventually and it turns out that these rectangular buttons might not be so bad.

I marked off the shape with dots spaced 1/4" apart (and 1/8" from the edges):
HERMS_Buttons.jpg


Then I drilled those out with 1/4" holes, which left holes that ended right on the lines and touching each other (the middle of the thing basically fell out as I drilled.)

The shark-fin shaped teeth that were left were easily removed with the dremel cutting disc and grinding stone and I cleaned out the corners with a small file. This picture looks a little ugly, but that's because it is an extreme close up and I did slip through a couple times with the grinder leaving those circular scrapes on the surface):
HERMS_Buttons_004.jpg


But, the end result is that the switch went in nicely and looked good (except for the scrapes I made with the grinder which you can see just off the end of the thing):

HERMS_Buttons_001.jpg


It took about 20 minutes to do this. I only have a couple of these to install, so I think I can manage it. I'm pretty happy about the whole thing.
 
An 1/8th inch drill bit to cut the corner holes and a jewelers saw would probably make real sharp and pretty cuts. Probably take a long time and a lot of patience though.. That switch mount looks decent Walker. Hope it works out for you now.
 
I discovered a shop in my town that sells industrial controls, dropped by yesterday and found out that a guy I went to high-school with works there... and his family owns it. Anyhow, they have punches for pretty much everything. I'm taking my panel over after work and we're going to punch the remaining holes I need to do in my panel.

Not that this helps you, but maybe you could look for a local shop that does industrial controls and may be willing to help a brewer out. They even have a square punch the size of my PID (which I cut out with a dremel cut-off wheel).
 
0.125" thick? >??~?~?~~?
What was it made for Nuclear blast survival?
I can see 0.0625" (1/16") but eighth inch is wildly heavy.

Are you sure it's 1/8"??

To cut 1/8", I'd resort to a slow speed reciprocating power saw like a Bosch hand held jigsaw loaded with a steel cutting fine tooth blade and I'd use oil on the cut lots of oil. Of course you have to pre-drill the cut outs with a drill the size of the blade to get the cut started.

I just checked their site:
http://www.hubbell-wiegmann.com/2004/pdf2004/DN412C.pdf
It's 14 gauge which is pretty damn thick: 0.074"
 
0.125" thick? >??~?~?~~?
What was it made for Nuclear blast survival?
I can see 0.0625" (1/16") but eighth inch is wildly heavy.

Are you sure it's 1/8"??

To cut 1/8", I'd resort to a slow speed reciprocating power saw like a Bosch hand held jigsaw loaded with a steel cutting fine tooth blade and I'd use oil on the cut lots of oil. Of course you have to pre-drill the cut outs with a drill the size of the blade to get the cut started.

I just checked their site:
http://www.hubbell-wiegmann.com/2004/pdf2004/DN412C.pdf
It's 14 gauge which is pretty damn thick: 0.074"

I'll take a picture and post it. I tried to snap a picture of the thickness of the stuff but flash of the camera washed the image out and you could not see anything.

It might be a little less than 1/8", but it's definitely more than 1/16"".

edit: I missed your update about checking their website. It certainly looks thicher than 0.074" to me, but maybe I am wrong.
 
BTW: Cliff... that box you linked to does not look like mine. I do see that most of the Weigmann stuff is 14 gauge, but they also have 12 gauge boxes (0.109").

I'll measure carefully tonight if it isn't stamped or stickered right on the box itself.
 
Greenlee makes punches for just about anything, including 1/16 adn 1/32 DIN - which covers most PIDs. Unfortunately, they're several hundred bucks. Omega sells the 1/16 for $475, and says it's good for up to 14 ga steel.
 
Greenlee makes punches for just about anything, including 1/16 adn 1/32 DIN - which covers most PIDs. Unfortunately, they're several hundred bucks. Omega sells the 1/16 for $475, and says it's good for up to 14 ga steel.

Ummmm..... thanks for the info, but I don't really consider something that costs more than the rest of HERMS system to be a good solution for cutting a hole in the box. :D
 
Me niether, I was just giving an example of how much they were. Diatom had the right approach - seek out a shop that can do it. Or do like you're doing. I did a panel with a 1/32 DIN PID, just drilled, jig sawed and dremeled, like you.
 
10-4.

This thread kind of got going in a different direction than I had intended. This was meant as a heads up to folks getting ready to build something like HERMS or RIMS and inform them that they need to think through the cutting and drilling and installation of parts that lay ahead to help make the proper choices for their parts.

It kind of turned into a thread covering solutions for my problem, being that we are all generall good at problem solving and helpful folks. Good info and I'm glad to listen to all the advice.
 
Harbor Freight sells knockout punches that are inexspensive, they are made in China so inspect the threads carefully before leaving store (my first set was unusable). That being said you would make your life a lot easier if you cut a large opening out of the face and overlaid it with an aluminum panel. It machines with most wood tools and if you want to get fancy you can have it anodized cheaply. My 2 cents.

Bill
 
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