16 replies to this topic

[harrismetalsmith]

Hey Nazel owners, would you mind chiming in on this picture of my bottom valve on my 2B?
I am wondering about the holes and grove on the end. I think this may be a later modification of the valve. For exhausting extra air. I say this because when I first got the hammer the cushion plug was way too long and instead of engaging the the bushing with a precision fit of a few thousands it was undersized by about a 1/4", and it was about 10" long. I think instead of allowing the cushion plug to cushion the top of the ram stroke they made that stupid plug, out of steel no less, and used the holes and grove in the picture to exhaust the extra air.
The hole travel path goes from the main valve portion travels down through the valve to the grove on the end and gets dumped into the crank rod cavity below the bottom piston housing. In other words it gets dumped outside the pressurized portion of the machine, for what reason? I am thinking this is the main reason I have not been able to get the ram to draw up when I first power on. The only reason I can figure is that when they had the pedal all the way down, at full ram stroke, with the crappy cushion plug fix, they needed to exhaust some air to keep the ram from smacking up top.
Just wondering out loud. Want I really want to know is if anyone else has holes and a grove like that in their bottom valve.
I know from the patent info I posted earlier that they changed the design over the years. My hammer is a Nazel, not a later Lobdell or United. Serial # 1284
Also curious about the year of manufacture. I f anyone has a serial # close to mine and you know anything about it's date, please let me know. I think it's 1930'ish, not sure.

 Nazel valve 1.jpg   349.71K   71 downloads


 Nazel valve 2.jpg   257.96K   61 downloads

Bring on your thoughts.
Thanks for any help!!!!

[Dave Hammer]

Email coming your way....

[harrismetalsmith]

Dave, thanks for any info.

I sent the valve sleeves out to be precision honed, they wound up cylintricaly grinding them because the slots are so large, the hone would slip through. I have brazed up the valves themselves, once the sleeves come back, I will turn them down, and lap them into place. Hopefuly this was a large part of my problem, air leaking around the worn out valves. If I still cannot get the ram to draw up, I am going to temporarily plug that hole with some UltraBlack, and see what that does. Bob Bergman suggested to temporarily plug it in an e-mail.
An interesting note on the valve sleeves, the honing guy said they are not regular cast iron, he said they had a high nickle content in them.
I will post some pictures of the process.

[harrismetalsmith]

 Valve lapp.jpg   374.81K   56 downloads

Yesterday I finally put the valves back together. As I posted earlier the valves were sent out to be profesionally cylintricaly ground. The guy told me the one larger one had a slight " belly" down the lenghth of it. They were dead on when they came back.
First I brazed the valves with low fuming bronze rod. Then I turned them down on my lathe to within .001 to .002. I re-installed the sleaves into the machine and then lapped the valves into place. After putting on the covers, I powered up, and.................
The ram finaly drew up into the housing!!!! It also now has good control in the planishing, light blows, another thing it didn't do before. I am PUMPED!!! This has been a way long process, and I can see light at the end of the tunnel. I still have a shake to take out of the main crank shaft, and get a new round belt to the oiler. I am manualy cranking the Manzel oiler during testing. Later on I will post a video.

 Turned valve.jpg   347.09K   52 downloads

[John Larson]

Congratulations, Matt. I know it has been a long process of laborious investigation.

[harrismetalsmith]

Hello John,
I just read your blog, very nice. Thanks for the encouraging words. It has been a VERY LONG process.

[harrismetalsmith]

 brazed valve.jpg   400.36K   69 downloads

 ground valve sleeves.jpg   162.87K   62 downloads

Here are a few more pictures of the valve re-build. The first shows the valve after brazing, ready to turn down on the lathe.
Ths second is an inside view of the valve sleeve, before lapping in the valve.

I was able to get the knock out of the main crank shaft. turns out the back bearing was shimmed .010, which I reduced to .004. The front bearing was shimmed a crazy.045. I reduced it to .008.
The beast is getting in shape!

[John N]

Keep an eye on the temperature of the crank bearings. Ive rebuilt a few hammers that were shimmed to compensate for a bent crank. Put the bearings back to standard clearance and they run hot, pick up or whatever.

[harrismetalsmith]

John N, on 17 September 2010 - 10:05 AM, said:

Keep an eye on the temperature of the crank bearings. Ive rebuilt a few hammers that were shimmed to compensate for a bent crank. Put the bearings back to standard clearance and they run hot, pick up or whatever.

John N.
Thanks for the heads up. I will keep an eye on that. I think the crank shaft is slightly bent. About 20% of the teeth on the flywheel had been damaged by something. Maybe at one time the crank shaft and flywheel took a hit.
I have it set up to run on a clutch type belt. My phase convertor is not powerful enough to start it cold, without the motor spinning.
However, it does seem to be running much better after re-shimming.
Do you have alot of experience with Nazels?
Thanks, Matt

[Dave Hammer]

Matt

Are you aware that you can unload the compressor so when you start the motor, it has less load on it?

[harrismetalsmith]

Dave,
No I am not aware of a way to take the load off the piston. Is that the ball valve setup on the side of your 3B? Do you hook that up to the plugged pipe thread hole between the valves?
Yes I would love to know of a way to do that!
Thanks

[Dave Hammer]

Matt

Yes... And this is thanks to others on these forums. I only learned about doing this a few months ago. Remove the plug that is between your valves on the linkage side. Install a pipe nipple with a large ball valve (the nipple has to be long enough to get the valve beyond the linkage. Open the valve before you put power to your motor, let the motor get up to speed, then close the valve. It's noisy, but it unloads the compressor. Obviously, you could add more plumbing to make it less noisy.

[harrismetalsmith]

Dave,
Thanks for the info. I removed the plug just to test that, and while it made it easier to start the motor, I still think I am going to have to clutch start it for now. My phase conveter is a bit redneck. I am using a "pony" motor to get my 15 h.p. spinning, and them throwing power to the 15 h.p. It works for now, I would like to refine my phase convertor, and get more starting power.
I am going to use that ball setup valve anyhow, because it takes strain off the motor start, hopefully prolonging the life of the motor. I have the 2B running on a 1200 rpm, 7.5 hp motor. Those low rpm motors are hard to come by, so I appreciate the info to make it last.
Thanks,
Matt

[Dave Hammer]

If you are having start up issues for a 7.5 application motor using a 15 HP converter, I would guess (assuming the motor is good) you have a problem delivering power to the 7.5 HP motor. A 7.5 motor should start, under any appropriate load, easily on a 15 HP converter.

Have you measured the voltage at the 7.5 HP motor? I'm no expert on this stuff, but I've read that the power may not be "balanced" very well (across the three legs) when the generating motor is "pony started" (and there are no capacitors for balancing the legs involved). I don't know what the power impact is on application motors, but it certainly can't be optimum.

I bought a "black box" from Anderson Converters "http://www.andersonconverters.com" for my converter, then provided my own motor. Click on their link to rotary converters, then page down to a price list for rotary panels. Today's cost for a 15 HP panel is $299 (plus shipping). If you want a remote start capability, I think it adds $100. You can build a panel cheaper (in $ cost), but you may end up spending a lot of time getting it working (based upon the experience of several of my friends).

One other thing.... Have you tried switching around the wires at the 7.5 motor (which wires are connected to the leads from the converter)? It doesn't matter which direction that motor runs and sometimes I've noticed the motor will (start and/or) run better with one wire hookup combination over another. Everyone tells me it shouldn't make any difference, but with some of the 3-phase motors I have used, it makes a HUGE difference. I just make up a chart of the wiring possibilites, and run through them to see where I get the most power (visually and audibly observed). If someone has an idea why this should make a difference, I am all ears.

Also.... Are you sure you are getting acceptable voltage levels at your application motor? If you measure the voltage and it is low, check the wire gauge against the distance the converter is from your single-phase power panel AND the distance from the converter to the 7.5 HP motor. If the wire is not of sufficient gauge, you will have a voltage drop across the wire, and may not be delivering enough power for the motor. I had issues with this when I wired for my 3B. I've been told acceptable voltage drop is 3-4 percent. The guideline for increasing the wire gauge varies, depending upon where you read it. I have seen that you need to increase the wire gauge one unit for every 50 or 60 feet of distance (beyond the initial 50 or 60 feet). You can find an online calculator at http://www.csgnetwor...resizecalc.html to get a recommendation for the gauge of wire you need.

[harrismetalsmith]

Dave,
I appreciate the info. I saw Anderson, on ebay, and wondered if they are worth it. I will probably drop the $ on your recomendation. I know the three legs are unbalanced, I just got sick and tired of trying to balance it with capacitors. I'm a blacksmith not an electrical engineer.
I have the correct size wire running to the motor. I also checked it with your link.
I have measured the voltage, acording to the meter, the "fake" leg is high.
I think I read in another post that you are running your Nazels off a 15 hp converter? Is your 3B motor a 10 hp? Is that correct? If so I will add the box from Anderson, and I should have no trouble with the 7.5 hp on my 2B.

[Dave Hammer]

Yes, the motor on the 3B is 10 HP. It starts fine with the 15 HP converter.

[Phil Krankowski]

Careful with that calculator, it will give too small a wire for some situations, so check minimum wire recommendation and make sure. Seems good for long to very long runs though.

My test was a 6 foot run at 200A, 208V or 240V, it returned #12 wire, so it is at least obvious in being wrong in that case. (such as a sub-panel, and wrong as minimum code goes)

Phil