OK,In Southern California, I have a 1970’s style 1150 square foot house. Currently it has a 100 amp service panel . I need to upgrade ( not enough room in panel for additional circuits)We need more power to run modern appliances ,etc. I don’t think I can do anything but go through so cal Edison and upgrade to a new 200 amp service panel. Anyone out there familiar with this process and/or any suggestions on this subject. Thank You
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Address your Q to huck. He's familiar with that turf, and probably on SOP for such a project.
Good luck.
The best reward for a job well done is the opportunity to do another.
You can't get the right answers unless you ask the right questions.
Chances are, even with everything running on a hot summer day, you're not using anything like 100 amps. Have an electrician do a load calculation; I'm sure you don't need a service upgrade.
Not enough circuits? Then you don't need a bigger service ... you need more circuits. This is best accomplished by having your service ("main") panel serve several satellite "sub" panels. Again, chat with an electrician as to your plans, and the best ways to do this.
AC (20A), electric range (40A), electric water heater (30A), electric dryer (30A) -- could easily be 100A.
The mark of the immature man is that he wants to die nobly for a cause, while the mark of a mature man is that he wants to live humbly for one. --Wilhelm Stekel
Nonsense. That's why a REAL electrician ... a licensed master or electrical contractor ... needs to make the evaluation. It's a professional judgement call - time to hire a professional.
Apart from looking at the specific site .... no two places are the same ... there's the matter of taking actual current measurements. I've measured the draw for many residences, some quite large, and the loads are never as high as people think. That's why they screw themselves, and buy larger generators than they need - but that's another topic.
Our OP has also mentioned renatl spaces. In many places, that removes this from the DIY, as the law will require the use of a licensed contractor.
More circuits is a completely different issue from "more service."
In California, you can be a "homeowner contractor" and , with permits and inspections is perfectly legal.
If this is a rental you are not a "homeowner", for permit purposes.
RE: homeowner contractor.
On at least one part of the other coast, Delaware, a homeowner can be permitted to do their own electrical work, in their own home.
Homeowner is issued a "homeowner's permit", all phases of electrical work are allowable with this permit. From wiring an addition to a complete electrical service upgrade. The permit allows the work to be inspected.
Restrictions: No swimming pool or spa electrical work. House cannot be currently for sale or rent.
"Currently" is the operative word - if the home is vacant or occupied by the homeowner, the "homeowner's permit" is valid. If the house is currently listed for sale or rent, the permit is not valid.
As soon as the electrical work is inspected and passed - homeowner can do anything he wants with the property - sell or rent.
JimNever underestimate the value of a sharp pencil or good light.
"AC (20A), electric range (40A), electric water heater (30A), electric dryer (30A) -- could easily be 100A."Dan
Your statement is what most homeowners believe. Adding up the circuit breakers amp rating is not how NEC does load calculations. The calculations are base on watts per square foot and types of loads. My guess for this house is closer to a 70 amp panel being required, but I think 100amp is minimum for SFD.
I'll admit that the numbers are the protected values, which are 20-30% higher than worst case normal operating currents, but it's easy to conceive of situations where all those appliances would be operating at once. To ignore that scenario could produce a very expensive problem for the HO.
The mark of the immature man is that he wants to die nobly for a cause, while the mark of a mature man is that he wants to live humbly for one. --Wilhelm Stekel
I evaluated it all.Many circuits are already over-drawn. Im a carpenter by trade, but I have experience in all phases of construction, I traced and noted every circuit , and if you include all of the constant demand , there is no room for intermittent demand ( like hair dryers and toasters ,ceiling fans ,etc. ) Its a vacant rental being upgraded ,(basically new everything.)and we dont want to hear about all the circuits popping like popcorn when a renter moves in...who knows what a renter will want to run on these already full circuits.
Another possible reason to replace the panel is if it is a Zinnsco or PushMatic. Both were commonly installed in tract housing at the time yours was built and both are notorious for failure to trip properly when they should or, in Zinsco's case, arcing at the breaker/bus connection.BruceT
You're insane.
100 AMPS won't run the hot tub (50A) and the inline water heater (120A) much less anything else.
My doghouse has a 100 A sub-panel, because he gets a little out of hand with holiday decorations.
That's the trouble with general answers. The only way to judge whether a service is adequate, or if an upgrade is warranted, is to have a licensed master electrician perform a load calculation. If the structure is already existing, the calculations need to be confirmed by actual measurements.
The trouble with some of the replies I've had on this thread is that they are simply adding breaker sizes ... which is NOT the way services are calculated.
This is something that calls for 'professional judgement.' A pro is hired for his judgement more than anything else. He's not just some guy with a tool belt.
I don't see our original poster adding loads ... just circuits. There's no reason his existing service won't be adequate. Yet, I haven't been to his place, so I don't know this for sure. To be sure, I need to be there, to measure what he's actually using, and do a load calc.
I think I can give general answer for my area of Southern Calif.
I have seen 400 amp services, (with 3 phase of their elevator) for mansions around Beverly Hills down to 30 amp glass fuse in South Los Angeles.
The most common problem in most 70's home is a kitchen appliance trips the circuit breaker. In the 70's NEC required 2 kitchen circuits, a separate circuit for washer/dryer, dishwasher and garbage disposal. Typically, the HO has a problem when the Microwave, coffee maker and refrigerator is on the same breaker.
If half size breakers do not fit or no can do, an easy fix is to add another kitchen plug to the garbage disposal or dishwasher circuit. It may not meet NEC code requirements, but most people do not use everything at the same time.
When I have parties, there may be 4 crock pots, 5 warmer trays, coffee maker, hot water air pot and tea pots, I run a heavy duty cord to the dishwasher and garbage disposal circuits.
My house was built in 79 and all I have is the 2 20 amp small applicance circuits.On that I have a CT MW, toaster, trash compactor, GD, hot water dispenser, DW, and refrigerator. Then a blender, coffee mill, and hand mixer. But those are all relatively small loads.I have not traced out what is on which circuit. I know the trash compactor is on the same circuit as the MW as the light dims when the compactor cycles.But other than the DW and the refrigerator everything is such a short cycle that I have never had a breaker trip..
William the Geezer, the sequel to Billy the Kid - Shoe
Hi
In 1997 I got a permit and wired whole house and only had to move on switch away from a shower. I put a 200 amp panel in for my wood shop and ran a 100 amp to house. Payed a journey man to run sub panel. He found a major mistake I made in the first panel and the inspester did not pick up on it.
Now here in Sask CA we can only work up to the panel and you need a journyman to do panel work.
Some of this stuff is easy but!! your insurance company may not pay if you did the work your self! I would rather pay an electricain that dicker with an insurance adjuster and day of the week. Some stuff like Arc faults are just hard to swallow but most codes are dumbed down so much to protect any idiot from themselves.
Read the insert with your hair dryer, do not use in shower, do not stand in water, don't use under the influance of Drugs or alochol. Each statement is made from a lawsuit filed by some one who just can't think. Period.
Why to they not have a" do not lick" disclaimer on 9 volt batteries or do not lick on steel poles in freezing weather?
I used to think the writing on an gas welding gauge "do not oil" was dumb, How many guys went up in smoke before they realized not to oil the gauge.
Some days you wake up looking to learn something, some times the knowledge gets jammed down your throat. Chose you battles carefully. A good night sleep beats the hell out of shelling out for paying for peace of mind. The bill for the electrician will be small in the big scheme of things. And ripping out completed work for one mistake will make that bill look smaller every day.
Around here a 200 amp panel is just a few more dollars than a 100. All but the cheapest idiot will save 50 bucks. Put in the 200 and leave a few spots for future needs.
Stay warm stay safe
BB
When did insurance companies start going after people for shoddy work? I think you are mistaken here as my father in-law is into insurance and he says no way they do that. If your shingles blow off, they do not go check on how many nails were holding the shingle on and then go after the roofer or homeowner right?
When they have to flip the bill for shoddy work.
Someone show us one example of this happening of going after a homeowner or a trade for bad work.It doesn't happen.If they catch you burning the house down, that is different. If it is because your mother wired a ceiling light wrong, they don't do that.
Edited 12/19/2008 10:35 pm ET by Westcoast
Here in NC a homeowner can pull a permit for some pretty serious electrical, the Dept of Insurance is behind you if you have a permit and proper inspection by the AHJ. Go it on your own without the above and your insurance Co can beg off paying if it proves that is what burned you out/damaged. Samething structurally I believe.For those who have fought for it Freedom has a flavor the protected will never know.
So if you buy a 1 year old home and the previous owner ran an extension cord through the attic for a new hood fan and the house then burns down, the insurance company is coming after you??Find me one instance of an insurance company going after a homeowner for unpermitted work and then proving it.
I have ask and ask for people to show me in their polices where there is an exclusion for HO DIY work, unpermitted work, uninspecrted work. And no one every has.In fact I have gotten replies from people in the insurance business indicating that there are no such exclusions. In fact one told me that they insurance against stupidity.Now they can and will try to recover looses from a 3rd party. And if it is clear that there was gross negligence it does not matter if was inspected and permitted or not..
William the Geezer, the sequel to Billy the Kid - Shoe
Bill you're exactly right, they insure against stupidity.If you take off the railing around the stairs and your mother inlaw falls 10 feet (what a shame) they still cover you as part of the liability end of things.
On another forum, one of the members has documented numerous such instances in New Jersey. Examples have included:
1) Settlement greatly reduced, covering only the part of the house that was orignally there, and not the addition that was done without a permit;
2) Insurance claim leading to prosecution for an electrical upgrade, done by unlicensed 'side working' tradesman; and,
3) After a claim was submitted, the policy being cancelled, and premiums refunded, as the various non-permitted additions, etc., allowed the insurance company to claim that the house that burned was not the house they insured.
How do they determine which owner did it? Lets say the house has sold 4 times in the last ten years, who would be responsible. And what if you actually bought the house and had no knowledge of an illegal electrical upgrade?
That's not how it works ... plus, this is where the lawyers make their money. They love raining unanswerable questions ... lets them run up the billable hours!
What happens, first of all, is that a claim is denied. Or, a reduced settlement is offered. Disagree? OK, now YOU get to sue, and have to prove them wrong. Chances are, their pockets are deeper than yours, and they'll litigate until yours are empty.
Secondly, the investigators are no fools. The check the records; they check for permits filed, sale records, tax records, home inspection reports, even look at other properties you may have had. They also can date parts; for example, the 'yellow' reomx hasn't been around all that long. They know when certain methods were prevalent; when was the last time you saw a rubble foundation used?
More specxifically, it's pretty easy to tell when the single floor ranch they insured was really a two storey, with basement, home base business, and commercial workshop when the claim is filed.
This board is filled with all manner of folks who consider themselves expert at their trades. Well, investigators have their trade as well.
In my experience, most insurers are pretty straightforward ... but they have absolutely no tolerance for game-players.
I was involved in ther repair of a rental that had a fatal fire. While the cause was purely accidental, the landlord wasted no time getting clever. To no avail; the insurance company stepped right in and took over the repairs. As I said, they're nobody's fool.
Thanks for picking up the answer, I had no direct case to cite, just comments from licensed contractors, the head county building inspector, and a cousin who just retired from the NC Dept of insurance. Figured that was enough for me here in the east.
I agree that prosecution might be hard but like you elaborated, the insurance company can pretty well grab onto anything and fight it. Do not think I said anything about prosecution by the way.For those who have fought for it Freedom has a flavor the protected will never know.
Thank you for all the insight, and it certainly all makes sense to me.My Father inlaw (married to an outlaw!!) feels that there is a lot more shady insurance companys down in the U.S. than there is here in Canada where we are. He says here the insurance providers do nothing of that sort and just raise rates accordingly to risk.On a side note, My daughter is in university and lives in a small and illegal basement suite. There is sketchy plumbing, wiring, egress requirements, the whole fandango. I called the city building dept. where she is going to school and they admitted there are thousands of illegal suites and they can't do a damn thing about them. Tried to get through to someone at city hall but no one has responded to messages and emails.Makes me wonder why we try so hard to do good work and be professional when there is so much b.s. going on with everyone else.
You can add another 100 amp box or just get a 200 amp box. The price of copper has come down so now would be a good time to upgrade. You might want to look at making room for an inverter in case you want to upgrade for solar panels. I have 30 amp breakers for my garage so my tools are running cool even if the street lights are dimming when I through the switch.
There's a difference between non-permitted work and properly permitted work done by the HO.
The mark of the immature man is that he wants to die nobly for a cause, while the mark of a mature man is that he wants to live humbly for one. --Wilhelm Stekel
I'm sure things are different in CA, but I am in TX and just did a service upgrade and complete rewire to my 1950s house.
You will probably need to get a permit, install your new panel/service and pass an inspection. They will release it to the utility company so you can call them and have them move their lines onto your new equipment.
You should do a load calculation as others have suggested, or get an electrician to do one for you. You can use this worksheet: http://www.taunton.com/finehomebuilding/PDF/Free/Service_Feeder_Calculations.pdf
I had a 100 amp main panel and after a load calculation replaced it with 150. I had to run about 65 of feeder so going with 150 instead of 200 saved me a bit of money. 200 amp panels are easier to find, and seem to be the standard so I would do this unless you have a good reason not to.
Call your city and/or utility company, they should be able to point you in the right direction.
I did, and it's pretty straightforward. If it's vacant, you can make it easy and have them pull the service from the old box, put in your new panel next to the old one, and use the old one as a big junction box after you gut it. I replaced nearly all the wiring in my house instead to the new box, cutting over one circuit at a time.
Your first call to SCE will be to the planning department. They will send someone out to check out what is existing, like your feeder lines, and tell you where you can place your new service panel. They will give you, or place a sticker where it's OK to put your new service panel. Keep that sticker - your local building inspector will need to see it to verify you weren't a dork and put it where it didn'tbelong. You will then put in your new panel, and rerun all the lines or jumper them over from the old panel if it is dead. Then your local BI will look at it and say you are clear for SCE to connect it. Then you call SCE again fo the hookup. It's likely they will run a new feeder line - might even run a new one to your neighbor too, just for kicks.
BTW, as far as capacity goes, I'm with everyone else. While I was cutting over circuits from my old panel to my new one, the entire house was powered off a single 40 amp breaker. Never tripped. Electric oven, laser printer & computer, heated dishwasher, never an issue.
Tu stultus es
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
> BTW, as far as capacity goes, I'm with everyone else. While I was cutting over circuits from my old panel to my new one, the entire house was powered off a single 40 amp breaker. Never tripped. Electric oven, laser printer & computer, heated dishwasher, never an issue.Agreed, I did the exact same thing. 40 amps powered almost everything for me as well for the better part of a year while I moved each circuit over one at a time.
Thanks for your post. The other main respondent to this thread was so incredibly "rigid", and unhelpful. Although he did mention performing a load calc--which anyone can do.You laid it out very simply, that is all the guy who was posting the question was looking for. There is a strain of electricians who believe that electrical work should only be done by "electricians". They so need to get over it, this ain't rocket science.
It may not be rocket science, but have do you know the National Electric Code?
Try selling your house with multiple and serious violations. Do you know what is required of you to have a properly grounded "new" 200A service? Adding a plug or two isn't out of the ability of most people. Uprgrading a service under NEC guidlines correctly is. Card carrying journeyman have to complete a four year school with their apprenticeship.
How many grounding electrodes are required, and what size grounding electrode conductors? What size conductor for a 30A OCPD? Is your house a single phase or three phase system? Where are GFCI required? And AFCIs? What is a main bonding jumper and where are they required?
If you can answer these questions, than a service upgrade might be a peice of cake. If you can't, you had better call an electrician.
Ya that's all fine for journeyman electricians to know that stuff. My brother (a bean counter) just did his house and he had no knowledge whatsoever. The inspector told him what books to use and go buy, he read through them and re-wired his house.
Inspector came back to check it out, found one wrong size staples on two wires which even he said wasn't critical, they changed them right then, then checked everything out and went over it all with him and that was that.
A homeowner doesn't have to know the national code, the inspector does.
Edited 12/16/2008 10:16 pm ET by Westcoast
"A homeowner doesn't have to know the national code, the inspector does. "That varies a lot by the inspector. Both on how much they know. Ask BB about his electrical inspector that got the job from his BIL after he fail as a Wally World greater.And also by the amount that they are willing to help and guide..
William the Geezer, the sequel to Billy the Kid - Shoe
Just how many single family houses have you encountered with 3 phase power?
JimNever underestimate the value of a sharp pencil or good light.
It was a trick question. But believe it or not, I encountered a condo unit with three phase power today. Next question...............
Electricians are outrageously underpaid where I live. At least the commercial workers. Yes, alot of work gets done under the radar. In my locale, a permit is not required until you start dabling with the service. Circuits can be added by a homeowner, but any other type of service change requires a permit. I make good money doing electrical work on the side.
No, most homeowners don't need a copy of the NEC. Most carpenter's don't carry a copy of the National Building Code, either. Every electrician that I work with is required to carry the latest NEC. The sole purpose of the NEC it to protect people and property from the hazards related to electricity. That is serious business, and so is rocket science. The number one cause of house fires in the United States is from an electrical system malfunction. In fact, as much as 80% of house fires are from a fault of some kind. I think people need to understand more about electricity than they do, but take baby steps. I've done quite a bit of framing before, even some rafters, but I'm not going to fool anyone into thinking that I can build a house on my own.
Edited 12/17/2008 8:08 pm ET by arcflash
i agree with you. on the flipside, the supply of electricians is being artificially kept low. You never, ever see positions for electrician trainees. you do see journeyman electrician positions advertised.try getting into an electrician union apprenticeship position. they don't exist, unless you have a connection.in the meantime, in my state, more and more regulations are being imposed, making it harder for non electricians to do electrical work.this is great for electricians, as it drives the value of their services up, but everyone else gets a raw deal. a lot of work probably gets driven underground.it does not seem like anything is being done to address the growing shortage of trainees into this field. This is the most lucrative of all the trades, and the hardest to enter.where i live, all i see, are a middle aged guys, working alone as electricians. they never have an apprentice.if you have ever visited the jlc electrical forum, the attitude these guys have is mind blowing. you have got to be kidding.change an oulet--please, give me a break. you so need to get over yourself. the more restrictive electrical work becomes, the more off the radar work that will happen.
I got into construction after 22 years in science/tech field...began with 3 years of after work and weekend construction trades classes before starting a seven year career change apprenticeship(learning experience) then going on my own. During those first 4 to 5 years I just kept my mouth shut and tried to learn all I could while working with all kinds of residential construction types...electricians more often then not were the ones who "thought" they were so much more intelligent then everyone else on the job. Truth is most, but certainly not all, were not exactly the brightest of bulbs. Significantly overpaid compared to their actual ability, especially in those who were in their first 5 to 10 years in the trade.
Maybe it's me, but some of the comments made in this thread toward the "anyone can wire up their shack" are dangerous. What electricians do isn't really rocket science (I'm not belittling them), but there is a lot to know. It's the "subtle details" that aren't really covered or explained very well in the DIY books that get the DIYer into trouble. You're in a position where you don't know what you don't know.
I can give two reasons why inexperienced people should hire an electrician: 1. You're liable for your work, not the local inspector who may range from top-notch to moron. If you get top-notch, refer to #2, if you get moron, you or the next person who owns the house might suffer some unfortunate consequences of any work not done properly. And these consequences can end up with you visiting the lawyer, and perhaps (as the defendant) paying out multiples of the "savings" realized by not hiring an electrician. You can claim that the inspector signed off as the work being okay, but it's still your butt. So "work for free, and still pay dearly" comes to mind. 2. If you don't really know what you're doing, top-notch inspector politely infers you're a moron, gives you a lengthy checklist of "fix this" items, and goes away until his/her next visit. That "fix this" list can get expensive, both labor and material-wise. And depending upon your locale, those subsequent inspector visits may not be free...
This might helphttp://gfretwell.com/electrical/2005loadcalculator.xls
can give two reasons why inexperienced people should hire an electrician
Have to be careful here, by the same extension, a person could argue that it would be better foir the inexperienced to hire an electrical engineer--after all, that's te ultimate "design" authority.
Now, I think the argument could be best made that an electrrical contractor can be the best choice.
But, I also know EEs that are cheaper to rent than JM electricians.Occupational hazard of my occupation not being around (sorry Bubba)
Wife cared for the child of an EE.
He wanted me to finish the job he started finishing the basement of his 1995 house.
Wire size was OK but he just drilled through his floor joists where ever he wanted.
The plumbing sub hooked the hot water to the cold supply and vice versa.
Client wanted a quiet bedroom (w/legal egress), rec room, furnace, storage and to top it all off a combo bath, laundry and darkroom.
Elec sub did OK but inspector wanted an extra duplex.
So the GC (me) corrected the plumbing, ran the extra duplex, cut the concrete slab for drain (found nice rental ducted exhaust fan--still go there do to that), poured concrete over drainage cut, ground it smooth and installed sheet vinyl flooring.
Owners happy as hell. EE glad I did work and not him. Had a great house warming party. PS-- Deducted amount paid to subs after I presented them with MY bill. So much for EE's. TyrThings are not always what they seem; the first appearance deceives many; the intelligence of a few perceives what has been carefully hidden.... Roman Poet Phaedrus 15BC–50AD
Wife cared for the child of an EE. <LOL>
So? so did my wife, and DIL. <G>.
IMO, codes originally maybe were to protect the ignorant homeowner, they are now primarily for the purpose of enriching manufacturers (e.g arcfault breakers) and protecting political entities from extortionist litigation. Much of NEC is simply to have a one size fits all set of guidelines.
To make a broad statement, anyone can learn enough to do about any job they are physically capable of doing. Then ya gotta trade your time vs. $$ and desire to learn how to do stuff. Once you learn it, you have it the rest of your life.
Unless disabled, about the only thing not DIYable is internal surgery on yourself (ya can't operate unconscious)
BTW, have occasionally tripped 100A sub panel feeder breakers on own house , and often trip a 50 A breaker to the welder circuits on hot summer days.
EE types may or may not be the best source of information or design for residential applications. Ninety five percent of the EE types in my area couldn't wire up their thermostat, let alone change out an appliance outlet. When it comes to electrical, power circuits are in a different subclass of electrical and not an area where many schools place their emphasis. What has been said here is for the most part very very true. Unless your familiar with the NEC and you've got some construction/electrical trades knowledge, it's really to your advantage to get a qualified electrician to work on your home. A huge mistake would be not getting a permit and having the work signed off by your local building inspector, regardless of who does the work.
"While I was cutting over circuits from my old panel to my new one, the entire house was powered off a single 40 amp breaker. Never tripped. Electric oven, laser printer & computer, heated dishwasher, never an issue."Old breaker failed in the closed position? :)BruceT
Well Duuuuuh! Of course, the glow off the breaker helped light up the panel when i was working at night ;)
Tu stultus esRebuilding my home in Cypress, CAAlso a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
Come to think about it, those Zinnsco's might have been the first "arc-fault" breakers.BruceT
I agree with getting a licensed experienced electrician in to give you the direction and specifics, but it sounds like with your experience you can do the job. Tell me what to wire and do, and I can wire it up...you sound like the same kind of fella.
Anyway, are you sure you can't just add a 100 amp sub-panel? A more accurate load calc would probably get you there. I have a 100 amp panel and filled the darn box up quickly too. I also have a gas furnace, but an extra AC unit and electric heat bu that sucks up the panel space...if I had only known at the time about twin breakers or doing load calcs!
Point is that everything is safe and works, except my lights dim from time to time when you turn on the garbage disposal, or the fridge kicks on...yeah some things were done kind of haphazardly, but the house isn't overloaded and we have a micro, toaster oven, electric just about everything (except gas WH & Heat). You shouldn't have any problems running the 100 amp panel and subbing it off or putting in twins breakers.
The NEC load calcs says your house will work with a 100 amp panel. If you need more circuits you just get "half-size" breakers to add more.
A 100 amp panel is good for your house with A/C, electric dryer And electric water heater (which I'm sure you dont have them all).
Call any electrician, he will gladly charge you for 125 amp or 200 amp, they will never say "100 amps is good enough", cause they will not make any money.
Somewhere online is a NEC load calculator.
"If you need more circuits you just get "half-size" breakers to add more."Panels have rated limits on both the number of slots and the number of circuits that they can have.For example a panel might be rated 30/40. That means that it has 30 slots, but only 10 specific ones can accept tandems.other panels might be 20/20 which means that it has 20 slots and can't accept tandems in any slots.I suspect that the old panel has is probably even smaller and at that age possibly an obsolete brand.And it won't have enough holes int the neutral and ground busses.Most likely replacement is a better option..
William the Geezer, the sequel to Billy the Kid - Shoe