Restoring an old Jacobs 1800 Watt

[clintonbriley]

Cool,
So the springs on the blade shafts are torsion springs and not compression springs then.
That would keep any backlash in the gears from causing problems with blade alignment and
maybe reduce gear wear by keeping the blades from shaking.
Thanks Shadow

[Tom Sullivan]

I've been off line for a while, really busy with work and coaching high school soccer.  Just noticed the updates on the variable pitch hub.  I was wondering the same thing, Clinton, about the purpose of the springs on the blade mount shafts.  I had pretty much decided they were for the reason explained by Shadow, but was guessing.  Shadow, thanks for clearing that up.  My hub looks a lot "cleaner" than the one posted.  It must have been taken down, once not being used any more, and stored out of the weather.  I've been delayed getting my blades drilled out and just found out my shop's $1500 magnetic drill quit.  I sent it out for repairs on Friday and hope to see it back by the end of next week.  Not sure how I would "accurately" drill the blade mounting holes without  it?

Tom

[Tom Sullivan]

Well, I finally got to drilling my blades yesterday.  I took my drill press base off, put the press on a low work bench, leveled and squared it to the bench.  Since I have about fifty 25 lb. shot bags for my airplane work, I laid 100 lbs on the press to keep it from moving (it was pretty stable already).  Then I took an original blade out that was "mapped" for building the new blades, and verified I was straight to the drill press with multiple measurements.  I installed blocking and wedges to support the blade to the exact location required to properly drill the new blades.  Once everything was aligned, I secured the blades with 200 lbs of shot bags and started drilling.  I could only get just under 4" on the drill press for depth, so the process was repeated about 4 times (I pilot drilled to avoid drift with the big bit).  I imagine this process was streamlined at the Jacobs factory to be a lot faster than this.

My friend Larry delivered a finished slip ring to me on Friday.  I'll post pictures of that and the tail assy tomorrow.  I'm pretty much ready for paint now.

[Tom Sullivan]

I've finally gotten a wind power tab on my website for my wind turbine projects.  I uploaded a bunch of photos today for the Jacobs, if anyone is interested.

http://www.aluminum-solar-absorbers.com/wind-power-projects.html

We installed the slip ring into the bearing assy yesterday.

Time for paint.  Too bad it's not done, we're getting the best winds I've seen in months, today, and over the next couple days.

Tom

[clintonbriley]

Tom, nice job of restoring the tail assy on the jacobs.  The pictures are great, thanks for continuing to
document your work.  The winds here in lower Michigan have been very good too.  I've been meaning
to ask what are the steel plates that are bolted onto the sides of the original blades for?
Clint

[ginger48]

Per your photos, it appears your tail frame may be too short. When the tail is turned out of the wind (folded), the vane should extend out just past the tips of the blades.

[jacobs]

The original pre REA Jacobs tails were made in two lengths. The most common were 8 feet hinge pin to tip of tail, and then the 10 foot hinge pin to tip of tail.

[dnix71]

Shadow, I looked at your video. Why is there such a large gap between the blade hub and the front of the motor? Wouldn't that put extra stress on the front bearings?

Is it needed for weight balance?

[jacobs]

Why is there such a large gap between the blade hub and the front of the motor? Wouldn't that put extra stress on the front bearings?

Is it needed for weight balance?

The reason for the distance between the governor and the front cover is twofold. First is so you can service the front of the generator without removing the blades and governor. In the case of the 110vdc dual commutator generator, there's a set of brushes located there that you must to be able to service. Second, it's for clearance between the tips of the blades and tower. When using the original Jacobs windmill type tower, there's typically only about 8" clearance.

The bearings are large enough that the extra stress isn't an issue IF quality bearings are used.

[Tom Sullivan]

The tail is to the exact specs supplied to me by Kevin, measured off a turbine he has sitting on the ground.  The picture doesn't show the tail in the full yaw postion either, so there may be an illusion to the photo.

Tom S.

Per your photos, it appears your tail frame may be too short. When the tail is turned out of the wind (folded), the vane should extend out just past the tips of the blades.

[Tom Sullivan]

Tom, nice job of restoring the tail assy on the jacobs.  The pictures are great, thanks for continuing to
document your work.  The winds here in lower Michigan have been very good too.  I've been meaning
to ask what are the steel plates that are bolted onto the sides of the original blades for?
Clint

Clint,

Thanks for the comments!  As far as the wind, even the Breezy would have piled up some KWh's the last 3 days, but it's sitting on the floor at my dealership.  I picked up some good primer today from my hangar, some left over from an airplane paint job a few years ago.  Hope to prime parts tomorrow.  Spent all day today wrenching on my bird, trying to get the massive "once a year" annual inspection completed.  I may need the thing for business later this month.

 As far as the metal on the blades, this turbine was taken down from a camp north of me, and they had been patching the thing for years, and then it sat for many more in disrepair, before my friend Larry talked the owner into letting him take it down.  Out of 6 blades, from two turbines he was able to rescue, there was one blade that might have been usable.

Tom

[Tom Sullivan]

   Had a good weekend on the Jacobs Restoration, until late this afternoon.  Brought everything home to prep for paint.  I pulled both front and rear covers off the generator and sand blasted them.  I then pounded out the dents in the covers over a couple shot bags, and filled them with some filler to look nice.  Did the same with the nose cone.  Sand blasted all the cast mount pieces that attach to the generator.  I didn't like the tubular support on the tail frame (my welder wasn't real fussy when fabricating it), so I cut it loose and repositioned it nice and straight.  Ground and sanded the outside of the bearing assy and the tail structure.  Found the blades were too tight on the 1" drilled holes, so spent some time fitting them nicely too.
   When cleaning the blade actuating hub (first time this has got more than a casual glance) I found one shaft for the blades is loose, and the bearing nut on the outside is turned in farther than the other two by a lot.  So now instead of painting, I need to disassemble the hub / shaft and fix this problem.  Looking back to an earlier post by Shadow, he notes these are tapered roller bearing.  I guess I'll find out pretty soon. 

Argh!! 

Tom

[Shadow]

Yep, now is the time to check all 6 bearings in there.

If you loosen that outer nut and remove it, you can get in behind it between the housing and felt washer with a punch and tap the bearing to remove it. Then the Spring and felt will come out through the hole .

Loosen off inner set screw and whole shaft should slide through gear and out.

You'll notice on the one picture theres some red silicone, that is a factory weight that had loosend off,that is what persuaded me to tear it all apart. At slow rpms it went clik ...clik... drove nuts. I thought it must be a bearing. So found what it was and tightened it up and siliconed it and changed all the bearings over to greaseable ball bearing type bearings.

Your tapered bearings may be just fine but I had one bad one so decided the others may not be far behind.

After the hub was all reassembled I laid it out on a metal frame. Balanced it perfectly flat all the way around. Then installed all three blades and set the angle at 4-5 degrees then tightened everything down.

That way up on the tower I just need to slide the blades on and tighten . Already knowing they are preset to 5 degrees.

Hope this helps.

[Tom Sullivan]

Shadow,

I tore it apart last night; didn't take long.  I actually had time to prime (two part epoxy) everything else afterwards.  My outer bearings are sealed roller bearings (have no idea what the grease zerks are for at this location).  I see now that the springs on the blade shafts are torsional; they assist rotating the shafts back after speed induced blade pitch.  I was able to remove the outer bearings first, and then slide the shafts outward in the hub far enough to pull the inside shaft end out of the bearing, then pulled the shafts out of the hub with the gears on them (removing them inwards from the outer hub hole).  My inner bearings (taper roller) are pressed on the shaft pretty tight.  I was able to remove one with by placing the shaft/gear assy in a vice and using a punch to drive the shaft through the bearing.  The second one will require a press.  No possible way I was removing the gear from the shaft, with the tapered roller bearing on the end, while still in the hub.  I used a small crows foot bar to get the race out of the hub.
 A concerning find was flat spots ground on the three shafts where the gears attach.  I suspect someone in the past thought it necessary to do this.  Don't know if they had problems with the shafts turning in the gears once tightened?  I can rotate the shafts 180 degrees to avoid these flat spots so I have adjustment.  What's your thoughts?

Tom

[Shadow]

Hey Tom,

Sounds like youre moving right along.  Your outer bearings may have been changed over at one time. I popped the outer seal off my ball bearing type so the grease gets into the bearing.

Mine too has flat spots on the shaft. I think the reason they are there is so when you put it together with the gear tightened on to that flat spot, then your blades should be at the proper setting to face the wind.

On mine 2 of the blades worked out to be set about 5 degrees just by using that flat spot. But to get the 3rd blade to properly be set to 5 degrees it worked out I had to tightend the gear set screw right on the shoulder of the flat spot. So I rotated all 3 blade shafts 180 degrees and tightened them down accordingly. Hope you follow this.

There should be factory marks to replace the top retaining nut  that connects all 3 shafts and gears.

[Tom Sullivan]

Finally got some time off from the business to clean and prime the cast hub.  I've noticed some Jacobs have the fly weights painted the same as the rest of the turbine (silver), and some have them painted black.  Anyone know if this was an option, or fairly frequent practice in the field?  Also, my motor (not the end covers) is painted red.  I've seen a couple that way too.  I think the red breaks up the silver a bit and looks better.  Just wondering because I'm ready to apply the final paint.

One last item, anyone know where to get leading edge tape for the blades?  I can get some from my aircraft suppliers, but was wondering if there is another option, as I'm not sure how well that would work.

Tom Sullivan

[Shadow]

Not much help on the colors, mine was silver when I got it. The weights were black. I noticed on the photo where Mr Jacobs is standing on the tower with one it also has black weights.

My end covers are aluminum so I just polished them. I also have a set that were painted with aluminum paint. I painted the metal brackets on the blades black but I think they were originally silver.

My leading edges are thin copper , stapled on. I've never removed it

On Friday we had 30 mph winds most all day. When I got home I had to go shut the Jacobs down. The 48 volt battery bank was sitting at 60 volts with 36 amps still coming in. My Morningstar TS 60 has never worked properly.

I noticed in those high winds, you can tell when the weights are activated it makes a buffeting sound then slows considerably and starts picking up speed again. When it starts buffeting it vibrates the tail spring, thats about the only noise I ever hear out of it. And I'm not sure how to remedy that. I may paint the spring with black rubberized under coating?

[B529]

Finally got some time off from the business to clean and prime the cast hub.  I've noticed some Jacobs have the fly weights painted the same as the rest of the turbine (silver), and some have them painted black.  Anyone know if this was an option, or fairly frequent practice in the field?  Also, my motor (not the end covers) is painted red.  I've seen a couple that way too.  I think the red breaks up the silver a bit and looks better.  Just wondering because I'm ready to apply the final paint.

One last item, anyone know where to get leading edge tape for the blades?  I can get some from my aircraft suppliers, but was wondering if there is another option, as I'm not sure how well that would work.

Tom Sullivan

http://www.xzeres.com/index.php

I've bought leading edge tape from owner of this company, Robert. Let him know you are restoring a Jacobs, he rebuilt and sold them a while back. I believe the tape is helicopter leading edge tape, it is made by 3M, 3" wide.

Clean the edge with acetone before applying the tape.

Kevin

[SparWeb]

I get it from EB Peerless (can't say if they have a store near you) and of course this is aircraft/helicopter leading edge tape.  You can also mail-order from Aircraft-Spruce, easy to find website, quick delivery (I think you're in the US, otherwise check on the CAN distributors, and order by phone instead of e-mail).

The LE tape that I use is the 3M clear polyurethane tape - 1" wide 8671 and 2" wide 8672.  The clean base surface is an obvious requirement, but note that it also responds well to a pass or two with the hair dryer as you apply it - makes it tackier when it's cold outside.  Using it for years and it doesn't even appear to "think about" coming off the bare cedar blades.

[Tom Sullivan]

Thanks for the feed back on colors and LE tape.  I have some of the 1" LE tape from Aircraft Spruce on my Mooney I installed years ago to eliminate aluminum chaffing at the tight fit between my flaps and wing skin.  It appeared worn while conducting my annual inspection this past couple weeks and I had ordered new tape.  While removing it yesterdeay, I discovered it was NOT worn, so I, left the original tape on.  I also discovered it was much more pliable than I remembered.  Anyway, I have enough that was purchased for the bird to do the blades now.  Will likely use the heat gun to soften it a bit too. 
  With everything epoxy primed with a good PPG automotive paint, I painted the PPG silver on this AM.  Will paint back side of the blades, tail and tail frame tonight and can start on tail art.  This thing may actually fly this month.

Tom

[Tom Sullivan]

I am assembling my variable pitch hub with new bearings, and have come across a few issues.  The felt washers for the inner seals were pretty rough, with the outer ones that go into the shaft/bearing adjustment nut the only ones looking good enough to reuse.  I replaced the inner seals with a Teflon washer cut to fit the application.  It fits pretty nicely and should hold most the grease in the bearing cavity.  The seals at the outboard point of the housing (inside the housing though) were damaged by the shaft springs.  When taking it apart, I found the springs were pushing into the bearing cavity, through the felt washers.  Since the outer bearing is a sealed ball bearing, I thought the need for a "tight" seal was less necessary.  I elected to make a Teflon washer to cover the outer housing shaft hole, and added a steel washer to avoid the spring pushing through the Teflon one.



When installing the outer ball bearing, I thought it should be driven up to the shoulder on the shaft (seems like the logical location), but found it very tight once within 1/2" of the shoulder, and the shaft starts binding up.  Looking at the "witness marks" from the previous bearing, it's evident the old bearing were located back from the shoulder too.



Once the shaft and outer bearing is installed, you can see the bearing is 1/2" back from the shoulder on the shaft (I have a file handle holding the spring & washers back).  Looking at it, at this assembly point, it's again evident the old bearings were not to the shoulder, or the springs would have not been able to penetrate the bearing cavity.



Looking at the outer adjustment nut, I would be running them in pretty deep if the bearing was up to the shoulder too.



Hope someone can give me some guidance on this??

Tom Sullivan

[SparWeb]

What about the bearing cavity in the housing?  When the bearing is inside the cavity does it come up to a shoulder in there, which would also dictate how far the bearing slides in to the shaft shoulder?  It also occurs to me that if you start with a 1/2" space, after a while of spinning the shaft shoulder would eventually pull down to the bearing. 

Wait a second, didn't you change the tapered roller bearings for Conrad bearings?  Gotta look back through the earlier entries of the thread to see where you mentioned that.  If that's what you did, then that's your answer.  Conrad bearings are not designed to take thrust loads.

[SparWeb]

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

I see it was Shadow that suggested that.  How did you deal with the radial forces on the ball-bearings?

[Tom Sullivan]

I was wondering about that too (shaft moving down the bearing after time), but the unit came apart that way and had run for years like that.  I'll mic the shaft and see if there is taper to it at the bearing surface, causing the extreme force to run the bearings up any further.  Otherwise, I guess I can machine up some spacers.

Tom

[Shadow]

Hey Tom,

  My bearings are identical to the ones you show in the picture. Mine were pressed on right up to the shoulder and after I removed them and reinstalled I tapped them right up to the shoulder again.

 In your first photo it appears to be a 'ghost'mark where the bearing was. But that could have been a tapered roller bearing mark.

I believe these all came originally with tapered roller bearings thus the adjustable crush nut.

When you put your bearing on it needs to go on quite aways and the adjustable nut turned in quite a bit or you wont get your blades on.  When my blades are installed the blade comes to within a 1/4 inch of the nut. So if you left that bearing out 1/2 inch away from that shoulder you may not get your blades on. But you could measure and see.

I drilled a tiny 1/8 ?  inch hole in the side metal seal of each bearing, then pumped in synthetic grease with a needle. I was surprised at the old crap that pushed out. Then Leave that hole facing the adjustable not so when I pump grease in a certain amount goes inside the bearing.

These bearings should last for almost ever when you think then never make a full turn. They just simply rock back and forth  not even a third of a turn.

Hope this helps.

[SparWeb]

Why did you switch from tapered roller to ball bearings?

I don't think the size of ball-bearings you are using allows the amount of thrust load that WT blades extert.  The tension load is surely more than 1000 pounds.  The difference in thrust load capability is about 4:1 between these two types of bearings (off the top of my head).

[Tom Sullivan]

Shadow,

   I put a mic on the shafts and they were exactly 1" throughout the bearing surface.  I sanded them down pretty good, greased the shaft a bit, and was able to drive the bearings in until they bottomed on the shoulder.  The hub had the exact same bearing combination when I disassembled it.  I don't disagree with Sparweb about the tapered bearings having a much higher rating, but ironically, the only failed bearings I had in the hub were the tapered ones.  All three ball bearing were in good shape.

   I ordered a self adhesive "layover" for the lettering on the tail.  I didn't want vinyl letters, as they are supposedly only good for about 5 years.  Would much rather paint the lettering on.  Not too much left now.

Tom

[Shadow]

Good Job there Tom,

Mine was the same way, had onr inner tapered bearing shot so replaced all 3 . The outer roller bearings are nice and tight and seem fine.

 I soaked all my felt washers in Varsol until they softened and was able to remove the hard crusty stuff. Then I soaked in gear oil, squeezed most of that out and coated with synthetic grease. They seem nice and pliable now.

These machines are relatively simple but very well thought out. Yesterday I climbed up and checked everything over. I could wiggle two of the blades enough to think they should be tightened up . So I removed the back plate and noticed the movement was the mesh in the gears. So I loosed the inner set screw for adjusting the twist on the blades. (I had previously marked the blade alignment with a paint marker in case I accidently twisted the blade.) I then tapped the brass gear towards the center to mesh the gears back in tight. Then retightened the set screw and went to the next one.

 I regreased everything, checked all nuts and bolts. Everythings good.  But today after reading your previous post again I maybe adjusted the wrong thing!  Maybe I should have checked that outer adjustment nut to see if it needed turning in which would suck the blade shaft back in towards the center hub?  Maybe the whole shaft has moved outwards and not just the brass gear?

After I pressed the bearings on I filled the cavity with grease but didnt overtighten the adjusting nut, cause I thought it would just push all my grease out. But now I'm thinking the bearing may have moved outwards.  Back up I go.

[Tom Sullivan]

Shadow,

Was you movement in the twisting axis or in and out of the shaft?  If it was in the twisiting axis, then the spider and gear contact was your culprit.  If in and out, then a bearing adjustment was required, much like a wheel bearing.  I tiightened my bearings up pretty tight, and then backed them off, like I do when performing wheel bearing adjustments.  If you had two loose blades in the twisting axis, couldn't you also look at tightening the spider gear, even if you needed to loosen the one that was tight?  Guess it doesn't matter, but if we run out of room sliding the shaft gears up, we can always go back to tightening the spider gear.

I finished the lettering on one side of my tail vane last night.  I didn't use vinyl; I painted the letters on.  Picture posted below.  I also added a picture of the partially finished hub, with the 2 generator cones and the nose bowl in the background, with fresh silver paint.

Tom

[Shadow]

Very NIce Tom,

Wow you do very professional work!  This unit will serve you very well for years.
 
 Yes my looseness was in the twist. In very slow winds when the blades are barely turning you'll hear a clik every now and then. Upon inspection I could see the shaft gear was slightly out of the larger gear . So I tapped it back in tight. But It could have came out for two reasons. One from the gears conical shape working against each other and simply slid it on its shaft outwards.(Which I remedied) Or I got thinking afterwards if the outer ball bearing moved on the shaft, or the whole shaft moved a 1/8 inch out it would appear as the same symptom. Right?  I'll do some more checking.

[Tom Sullivan]

Thanks for the kind words.

   On the slop at the bevel gears, you are correct.  Any looseness in the shaft tension on that inner bearing will also creat side slop on the gear, because the inner bearing is a tapered bearing.  If in doubt, you may want to loosen the jamb nut on the shaft gear before trying to tighten the outer shaft/bearing tension nut.  If the bearing preset was the culprit, and you tighten the shaft nut now, you will place undue stress on the gear and spider.

   Thinking about Sparweb's comments, and the fact that my ball bearings were not pressed to the shoulders, that might be the actual reason the tapered bearings failed.  The ball bearing on the shaft may have slid up some, after intitial bearing adjustment, and the tapered bearing was no longer tight in the race. 

Tom

[SparWeb]

I looked up Jacobs' orginal patent yesterday.  Looking it over I see the identical machine as you have on your desk...  with ball bearings in it.  Maybe those tapered rollers were an attmept to "improve" the machine by the last person to service the machine. 

Tom, everything looks great!  Thanks again for all the pictures.

[12AX7]

Hello...

Tom, I've never seen a "Jacobs" let alone the insides of one.  I've followed this thread (though not carefully) and have a "silly" question.  Maybe I've missed it in the text, but...
The miter gears (Brass?) are part of the system that feathers the blades at the same  angel??
Could you post a pic or three that show what/how they mesh with and how/if they tie into the yoke/fork castings?    I can see that these yoke/forks extend outside the main housing.  What/how do they tie into outside the housing?
I've looked at a few of the Jacobs patent drawings but get lost trying to figure it out (maybe I've been looking at the wrong drawings).
I'd also wouldn't mind seeing some of your "before and after" pics, side by side.

I'd also like to give you an "at a boy".   Very nice work, great pics!

ax7
Mark