Author Topic: Restoring an old Jacobs 1800 Watt  (Read 51106 times)

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B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #33 on: July 25, 2010, 07:58:00 PM »
I searched online for a diagram for the fly-ball type of jacobs governor without much luck.  Does the
flyball pitch the blades to feather or to stall to limit the power delivered to the generator in higher winds?
Does anyone have link to a flyball schematic or patent?
Clint

Pitch to feather. The blade actuated governor does so as well.

clintonbriley

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Re: Restoring an old Jacobs 1800 Watt
« Reply #34 on: July 26, 2010, 09:29:38 AM »

Thanks for the fly-ball patent link.  Lots of interesting designs out there.
Clint




B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #35 on: July 26, 2010, 09:32:03 PM »
Tom,

I'm not the greatest at explaining things, here's a picture showing the tail angle, roughly 3.5 degrees, the case is level. Your angle is probably going to be slightly different due to the lower hinge pin of your short case. I didn't pay much attention to the angle, brought the two angle iron pieces to a point, bend and check, bend and check the flat stock, the angle is what it is.

The brush holder is 5/16 plexi with a dado groove for the 3/4 plexi. Dado'd the 3/4 plexi to adjust the depth of the brush. Drilled/tapped 1/4-20 holes in the 3/4 plexi for the bolts.

Your blades look great! What did you use for wood?



Kevin

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #36 on: July 28, 2010, 08:20:40 AM »
Kevin,

   Thanks for more pictures and detail.  My friend Larry is building my slip ring assy, pretty basic project for him with his background.  I picked up the generator, attachment brackets, and blade pitch assy on Monday from Larry.  The Jacobs is his, but he has no location, nor will he build a tower or have a location to ever see it run.  It's mine to use for however long I want to use it, which will be until I get time to build a 17' or 20' machine.

   Anyway, I have everything at my dealership (not my home shop) so I can start fabrication of the bearing assy and the tail.  Will likely start on it next week, as I'm really busy at work right now.  With all the info posted here lately, and a few other sources coming through for me, I think I have enough detail to build all the missing pieces for the turbine.

  I made the blades out of pine, local pine I had sawed a few years ago and have dried for that long.  It's free, and I had no easy source for Sitka Spruce.  Since I intend to paint them with a good automotive paint, and cover the leading edges with an aircraft leading edge tape, I'm not too concerned about how well the blades will hold up.

   Glad the unit wasn't up last night.  We had 75 MPH winds go through here and a neighboring town got 5" of rain in a couple hours.  Speaking of that, I'm located in the U.P of Michigan.  Where are you at?

Tom


B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #37 on: July 28, 2010, 09:08:05 AM »
Tom,

75mph is just a breeze for that old Jacobs. One of my neighbors had one up for several years, it seen many 100+mph gusts.

I'm about 50 miles west of Denver.

I too have used a quality automotive paint and covered the leading edge with tape, should give you several years of service. Well worth the effort.

Look forward to your pictures of the Jacobs flying!

Kevin

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #38 on: August 06, 2010, 09:17:09 AM »
Kevin,

Any chance you could give me the height and width of the tail vane??  I have the bearing assy done, will drop it off with Larry to finish the slip ring.  I'll post a few pictures of the bearing assy when I get time.  I'm ready to start on the tail this weekend, but need the general dimensions of the vane.

   I plan to make the tail system like original, spring activated furling, mechanical (chain) to lock in place for normal operation.  I guess I'm curious why this seems to be a necessary function?  I understand that system allows for turning the unit out of wind in extreme wind conditions, but if I'm not around when those conditions present themselves, the turbine will not furl on it's own anyway.  If the unit has a problem that requires shutdown (generator failure, blade failure hub problem), I would drop the tower to service it anyway.  Anyone have thoughts on this???

Tom Sullivan
 

clintonbriley

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Re: Restoring an old Jacobs 1800 Watt
« Reply #39 on: August 06, 2010, 09:42:52 AM »
Hey Tom, the Mother Earth News interview with Marcellus Jacobs has been posted here before.  If you haven't read it I'm sure you would find it
interesting.  The interview is here.... http://www.motherearthnews.com/Renewable-Energy/1973-11-01/The-Plowboy-Interview.aspx

As I recall, Marcellus does mention the tail furling feature in the interview.  I was going to paste a quote from the interview,
but their website quit working before I found the pertinent part of the interview. 

Clint

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #40 on: August 06, 2010, 09:30:00 PM »
Tom.

I would prefer to have the ability to stop the machine if there was a problem, right now.  True it is unlikely you'll be around when there is a problem. Give me a single reason why not to have the ability to furl.

I climb all the towers I service, have yet to install a tilt tower. So for me having the ability to stop the machine is important. It's always calm when I climb a tower to service a machine, seems like more often than not the wind picks up while on the tower.

I've used a 1/8 cable opposed to a chain for the pullout, chain for the stop. Used this for a low torque sealed ball bearing swivel. http://www.petzl.com/us/pro/verticality/anchors/rigging-equipment-and-mobile-life-line-0/swivel
Have used an older version of this swivel for all the Provens I've install, works great.

Vane is 42hx30w.






« Last Edit: August 06, 2010, 10:23:07 PM by B529 »

dlenox

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Re: Restoring an old Jacobs 1800 Watt
« Reply #41 on: August 06, 2010, 10:25:02 PM »
Kevin,

Curious about your tail structure you are making - what size/thickness is the angle iron you are using?  I seem to recall that Jacobs used square tubing for this, curious as to the size difference.  Assuming that you are using the same length from pivot to end as well.

Dan Lenox

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #42 on: August 06, 2010, 10:49:46 PM »
Dan,

the angle iron is 1 1/2 x 1/8, the dimension used in every DC tail I've had hand and eye on.

Your 3rd picture on the 2nd page of this thread of a the current Wind Turbine Industries 20KW turbine is the only tail constructed out of square tubing to my knowledge, all Jacobs (DC and grid-tied) prior to this model I've seen used angle iron for the tail.

Kevin

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #43 on: August 06, 2010, 11:25:29 PM »
Kevin,

   I've dropped my Breezy down in 25 MPH winds with no issue. but now that I think about it, the unit was shut down and the brake was locked.  I had pretty much figured on making the tail furl, but was wondering if it was really necessary.  One reason why I was wanting to avoid it, my furling cable will need to 140' long.  I had already decided to use 1/8" cable; guess I will need to find a good price on that much footage.  The second reason I wasn't excited to do this, I will not need the cable for the 17' or 20' machine I eventually plan to build and install on this tower. So this will be a temporary addition to the turbine/tower assy.

   Thanks for the tail dimensions.  It appears the tail is stamped sheet metal ?  I was thinking about cutting one out of some light plywood and adding a couple vertical supports to make it more rigid.  Duplicating a thin / light weight steel one would be a bit more of a project for me.  Any thoughts??

Tom

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #44 on: August 07, 2010, 08:23:05 AM »
Tom,

don't see any reason why not to make the tail out of 1/2 - 3/4 ply. MDO would be a nice choice if you can find it.

The steel vain weights about 15lbs. Using ply would change the balance. I don't think that would matter, the Jacobs I had up for a while had a blade-actuated governor weighing half of what the fly-ball weighs.

To save some money on the cable, run 1/8 wire rope from the turbine/tail for the 15' or so to the swivel then a static (non-stretch) nylon rope to the base?

Your tower is 140'?

Kevin

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #45 on: August 07, 2010, 09:00:44 AM »
Kevin,

Thanks for the advice on the tail.

Yes, my tower is 140' tilt tower.  I got away without engineered drawings because I told the local code guy, who I get along with pretty well, that it was just a wind turbine tower.     ;)  Needless to say, there will not be any more of them this size in my county without a lot more paperwork.  Although I do not possess a PE Degree, my background in designing and managing the manufacture of log racks and log trailers made the code inspector a bit more at ease with approving the finished project.

There are some pictures of it on Gary Reysa's site;

http://www.builditsolar.com/Projects/Wind/TomTurbine/Main.htm

Thanks,

Tom

ginger48

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Re: Restoring an old Jacobs 1800 Watt
« Reply #46 on: August 08, 2010, 11:16:35 PM »

   It appears the tail is stamped sheet metal ?  I was thinking about cutting one out of some light plywood and adding a couple vertical supports to make it more rigid.  Duplicating a thin / light weight steel one would be a bit more of a project for me.  Any thoughts??

Tom

Any extra weight on the tail will, if you plan on long term use, wear the hinge pins more rapidly. I've seen hinge pins worn almost in half with the factory steel vane.

Shadow

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Re: Restoring an old Jacobs 1800 Watt
« Reply #47 on: August 09, 2010, 12:14:02 PM »
Hey Guys,

I just ran across this topic, dont get on here much anymore. Anyway I  have lots of good Jacobs info, photos, manual etc.

Mine is a Jacobs 110 volt DC 2500  watt. Which I've changed to 55 volt to charge my 48 volt battery bank. I have a couple 32 volt Jacobs.

Been flying The Jacobs since about april and am very  impressed with its performance. Seen lots of 40 amp-60 volt days.

I was missing the slip ring assembly, so built my own. if you want to email me I'll send what I have. sbakken(at)sasktel.net

I've tried posting photos on here lately with no luck.

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #48 on: August 09, 2010, 07:01:24 PM »


Any extra weight on the tail will, if you plan on long term use, wear the hinge pins more rapidly. I've seen hinge pins worn almost in half with the factory steel vane.
[/quote]

The hinge pins wearing prematurely is really a non-issue. I too have seen a couple pins half way worn. Here is what I know, my neighbor had a Jacobs up for over 9 yrs, no wear on the 5/8" hinge pins what so ever. Here's what I don't know, what is the history of those worn pins. I'm guessing lack of maintenance, maybe pull out cable and or tail spring broke, tail was rotating working on those pins.  I imagine after the rural electric was put into place most of the DC Jacobs started to slowly rot away. Keep in mind we can be looking at pins that are 60-70yrs old.
« Last Edit: August 09, 2010, 07:08:32 PM by B529 »

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #49 on: August 09, 2010, 07:03:38 PM »
Hey Guys,

I just ran across this topic, dont get on here much anymore. Anyway I  have lots of good Jacobs info, photos, manual etc.

Mine is a Jacobs 110 volt DC 2500  watt. Which I've changed to 55 volt to charge my 48 volt battery bank. I have a couple 32 volt Jacobs.

Been flying The Jacobs since about april and am very  impressed with its performance. Seen lots of 40 amp-60 volt days.

I was missing the slip ring assembly, so built my own. if you want to email me I'll send what I have. sbakken(at)sasktel.net

I've tried posting photos on here lately with no luck.

Shawdow, is your 110 volt case a dual commutator? Or did you rewind it?

Would you happened to have a blade actuated governor you are willing to part with?

I have a lot of other spar parts if you need anything, slip rings, various castings......

Kevin
« Last Edit: August 09, 2010, 07:10:52 PM by B529 »

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #50 on: August 09, 2010, 08:23:42 PM »
Shadow,

   I sent you an email where you can forward pictures.  I have custom built a bearing assembly, and my friend Larry, a retired Electrical and Mechanical Engineer, is building the slip ring to fit my bearing.

   I final sanded the blades this weekend and hope to drill them later this week.  My steel arrived for the tail; expect to get going on that tomorrow.  I found some old sign faces I removed a few years ago from a sign at my dealership that were made of 1/2" MDO Plywood, and were in real nice shape.  Will try to build a tail out of one of them.  Based on some research this weekend, looks like the weight of 5/8" plywood would match the steel blade, the 1/2" might be a bit lighter.

   Believe it or not, I found two local scroungers that had wire for me too (the 8 ga for the 120 volt is too light).  Both guys offered it for free.  I was looking at considerable expense for this phase, so I'm pretty excited to avoid that cost.

Tom

ginger48

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Re: Restoring an old Jacobs 1800 Watt
« Reply #51 on: August 09, 2010, 10:30:32 PM »
When the hinge pins are severely worn, usually but not always the longer tail was used adding additional stress to the pins. A long tail creates additional stress, similar as using a heavier vane. If both a long tail and a heavy vane were used at the same time, particularly in a dusty dirty environment, the end results unquestionably would be catastrophic.   I've seen badly worn hinge pins on machines after only 20 years of use without a heavy vane. If you can't do it right, wait until you can. You'll be glad you did.

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #52 on: August 10, 2010, 01:08:54 AM »
Ginger48,

Not sure if you're advising me or one of the other posters in this string.  My tail will actually be lighter than the original steel one.  In addition, we fabricated a piece of 3/4" bar stock to fit over the pivot pin, greatly increasing the contact area between the tail structure and the pivot pin.  (I'll be posting update pictures fairly soon).  I have no concern of wear when considering the above two features of this restoration, especially considering the original pins are worn less than 5%, after somewhere between 40 and 50 years in the air.

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #53 on: August 10, 2010, 01:40:56 AM »
Clinton,

I finally got a little time to read the Mother Earth News interview with Mr. Jacobs from 1973 about his wind turbine business.  At one time he had 260 employees working for him, producing 8 turbines per shift (3 shifts a day).  His sales of the wind turbines generated over $50 M, in 1935 to 1950 dollars!!!

Thanks for the awesome link.  That's definitely a link worth reading for any Jacobs Wind Turbine fan!!

Tom Sullivan

dlenox

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Re: Restoring an old Jacobs 1800 Watt
« Reply #54 on: August 10, 2010, 04:17:03 AM »
Tom,

You may want to consider using some urethane bushings over the tail pivot pins.

It would save a lot of wear due to metal on metal, plus there are a ton available for things like automotive sway bars and control arms, a lot of them are between 1/2" - 3/4" ID, perfect for the tail pivot application.

Dan Lenox

ginger48

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Re: Restoring an old Jacobs 1800 Watt
« Reply #55 on: August 10, 2010, 07:34:44 AM »
Ginger48,

Not sure if you're advising me or one of the other posters in this string.  My tail will actually be lighter than the original steel one.  In addition, we fabricated a piece of 3/4" bar stock to fit over the pivot pin, greatly increasing the contact area between the tail structure and the pivot pin.  (I'll be posting update pictures fairly soon).  I have no concern of wear when considering the above two features of this restoration, especially considering the original pins are worn less than 5%, after somewhere between 40 and 50 years in the air.
I was commenting on the discussion about using 1/2" or 3/4" plywood for a tail vane and recommending the assembly be kept as light as possible.

clintonbriley

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Re: Restoring an old Jacobs 1800 Watt
« Reply #56 on: August 10, 2010, 09:35:54 AM »
Quote
I finally got a little time to read the Mother Earth News interview with Mr. Jacobs from 1973 about his wind turbine business.  At one time he had 260 employees working for him, producing 8 turbines per shift (3 shifts a day).  His sales of the wind turbines generated over $50 M, in 1935 to 1950 dollars!!!

Hey Tom,
Oh yeah, those are some very impressive numbers!  Joseph and Marcellus Jacobs were definitely a couple of brilliant guys.
Clint

Shadow

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Re: Restoring an old Jacobs 1800 Watt
« Reply #57 on: August 11, 2010, 01:17:09 PM »
Heres a link to the Jacobs I restored.

http://www.youtube.com/watch?v=1Mlgq4dsdV4

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #58 on: August 11, 2010, 01:56:48 PM »
Dan,

Good suggestion on the bushings.  Will look to see if I can find some.

Stan,

Love the video!! :)  With the original style tower, if looks like I was zapped back to the early 50's when viewing it.  I like the demonstration of yawing the tail for shutdown.  Seems to work quite well with the winds you were getting that day.

Thanks for sharing!!

Tom

Tom Sullivan

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Re: Restoring an old Jacobs 1800 Watt
« Reply #59 on: August 11, 2010, 02:14:37 PM »
   Making great progress on the Jabobs.  Cut out and sanded the tail vane a couple nights ago.  We got the entire tail "metal structure" built yesterday, and installed a yaw spring (found a good spring at Tractor Supply) today.  Tested the yaw function and it works good.  Just need to install the "spring protected" yaw stop cable.  Decided to check the blades for balance.  Good thing I did.  I guess laminated pine, with a few knots, is not the most consistant blade material in weight.  I weighed them at the tips and the base.   I drilled holes in the end of the blades (on the airfoil area of the tips), making the holes larger at the bottom of the hole than at the edge of the blade.  This keeps the lead shaped like a bell, not allowing it to come out of the blade unless melted out.   I then melted lead into them until the scale was within 10-15 grams of my heaviest blade.  I will finish over the lead filled holes with some bondo or a fiberglass epoxy/ micro ballon mix.  As for the mounting end of the blade, I think I can add weight pretty easy after the hardware is installed; that's where I found some "balance lead" on the old blades.

   Just an interesting note; I weighed the blade attach hardware, wondering how consistent the forged aluminum castings were.  With weights in the area of 185 grams, I was amazed two were a gram apart, and the third was only 5 grams more.  Pretty amazing for 1935 technology. 

I'm almost ready to start painting.  I'll try to post some pictures soon.

Tom

Shadow

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Re: Restoring an old Jacobs 1800 Watt
« Reply #60 on: August 11, 2010, 02:43:54 PM »
All the technology from that era amazes me. I weighed my 3 blades and 2 were virtually identical and the third required about 6-8 grams. I was told they used to sort blades according to weight this kept a set of 3 consistant.

Mine seems to be very well balanced, in high winds the tail spring will vibrate a liitle bit, thats about the only noise you ever hear other than the swish of the blades. And I'm not sure how to rectify that.

 I read where the tail spring idea was to assist the wife or children to be able to crank the wind gen. out of the wind if a storm was approaching. All you really have to do is unlatch the crank and hang on, the spring does the rest even in high winds.

dlenox

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Re: Restoring an old Jacobs 1800 Watt
« Reply #61 on: August 11, 2010, 03:36:59 PM »
Shadow,

Actually the tail spring is setup as a failsafe mechanism!  The Jacobs interview mentions this feature.

To make power the cable needs to be retracted and locked to maintain the 'normal' tail position.

If the cable coming down the tower broke then the tail would actually revert to the furling position.  Marcellus mentioned that other turbine manufacturers did this the opposite way, and if the furling cable broke then the users would have no way in which to manually furl the machine.

Dan Lenox

Shadow

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Re: Restoring an old Jacobs 1800 Watt
« Reply #62 on: August 11, 2010, 05:01:01 PM »
You are absolutely right Dan, I think where I got my info was just a magazine article telling about the different features of the Jacobs.   The author mentions the ease which anyone can turn these in and out of the wind.

Another good idea he has is the set of grounding brushes on the main shaft behind the prop. They go to a ground to dissapate any static picked up by the blades. These brushes are credited with saving  both the generator brushes and bearings from the negative effects of static.

B529

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Re: Restoring an old Jacobs 1800 Watt
« Reply #63 on: August 11, 2010, 08:33:57 PM »
Tom,

regarding balancing your blades, it is very important for the blades to have the same "moment".

How Jacobs originally balance the moment was he would place two blades on a jig across from each other like a teeter/totter, then add weight so they were balanced to each other. It is not a good idea to just add weight wherever.

Another way to get the same moment from blade to blade, weigh all three with bracket/hardware/ paint/leading edge tape..... Put a piece of flat stock (1/8" or so)in your vise. Balance the blade on the flat stock. For example, 23" from the root is the balance point. Go to the next blade, place a line/mark at 23", add the necessary weight to match the 1st blades weight, slide the weight up and down the blade until the blade balances at 23". Both blades will have the exact same moment and center of gravity. I've used tire weights, the kind that look like hershey chocolate bar segments. Screw/silicone them to the painted blade. This method has worked well for me. Learned this way to balance blades from a grid-tied Jacobs manual and a good friend who service/maintains a few Jacobs machines for the last 20yrs uses this method.

I have a soft spot for these old Jacobs. I service industrial woodworking equipment for a living. Most of the equipment I service is older than me, I'm 47. I service a couple Oliver 24" planers that are over a 100yrs old, they are amazing pieces of equipment. What I've always appreciated about the old woodworking equipment and the Jacobs turbines is they were built in an era craftsmanship, they were built to be rebuilt and they were built to last. Gosh, I sound like my grandpa.

Nice video Shadow, thanks for posting the link. Congratulations on getting it up, sure it will give you many years of service.

Kevin

clintonbriley

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Re: Restoring an old Jacobs 1800 Watt
« Reply #64 on: August 20, 2010, 01:50:44 PM »
Hey Tom (or anyone who knows),
In this picture there are springs on the blade shafts.  These aren't in the patent drawings.
It looks like the springs are there to push on the gears to keep them meshed tightly to
reduce backlash.  So then are the gears floating on the shaft and if so, are the gears and shafts
simply keyed or are they splined?
I'm also curious to know what type of bearings are used on the blade/gear shafts.  Are they
ball bearings or are they tapered roller bearings?




Thanks,
Clint

Shadow

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Re: Restoring an old Jacobs 1800 Watt
« Reply #65 on: August 21, 2010, 02:45:38 PM »
Hi there,

The springs are there to return everything to its normal run position. The cone shaped springs keep the weights tight against the housing until centrifugal force overcomes the spring pressure letting the weights move out. As the unit slows down the springs pull the weights back in.

The round springs on the shaft keep the blades tight in a a preset position , mine are 4-5 degrees to the wind.When the weights move out they twist the blades to a different angle to slow things down. After slowing down all springs pull evertthing back into normal run position.

The bearings are tapered roller bearings that can be greased. I changed mine over to ball bearings that can still be greased.

To manually changed the pitch on the blades ,there is a set screw on each gear that you loosen off . Then twist the blades to desired setting and tighten down.

Then when you reinstall your blades you just slide them on over the shaft, push a bolt through and tighten, also tighten a small set screw on the innermost part of the blade and your done.