Dempster Aunu-Oiled Rebuild

Share and discuss your windmill related projects.
User avatar
windybob
Posts: 3878
Joined: Mon Jan 14, 2019 5:59 pm
Location: Ames Oklahoma

Re: Dempster Aunu-Oiled Rebuild

Post by windybob »

ok well then this require some major surgery. The setscrew is easy to see. I don't recall if you have the hubs off or not. The setscrew is right under the brakedrum, and sometimes the drum gets in the way of removing it. If you can heat the outer hub (some) in the center by the shaft, and take a 1/2 inch thick, long rod, then you can hit the outer hub way down in the middle by the shaft, where it's thickest and drive it off. Then we can do a trick I learned a long time ago to get the brake hub off.
Call Dan Benjamin for parts. P M me for the phone number. IF YOU TALK TO HIM, AND HE HELPS YOU, THEN BUY FROM HIM. IT CREATES GOOD KARMA.
Wildcat
Posts: 17
Joined: Thu Dec 28, 2023 10:08 am
Location: McPherson, KS

Re: Dempster Aunu-Oiled Rebuild

Post by Wildcat »

I found the set screw under the brake drum. Haven't yet tried removing it. I haven't been able to remove the wheel and brace spiders. Don't want break any more than I've already broken.
You do not have the required permissions to view the files attached to this post.
User avatar
windybob
Posts: 3878
Joined: Mon Jan 14, 2019 5:59 pm
Location: Ames Oklahoma

Re: Dempster Aunu-Oiled Rebuild

Post by windybob »

I tried to explain how to start taking the hubs off. If you work on these things, you always take a chance of breaking something, it's part of it. But taking care, and using patience, is the trick. If something breaks, it 's part of the process or tryin to fix something. WHen you remodel a housem, or a room, you have to break a lot of stuff to get the remodel done. Not so much on a mill, but it can, and does happen. If you do not wish to take a shot at rmoving hubs like I reccomend, then we are at a stop point. I gave instructions on the outer hub, once you got that done, I will explain tricks for the inner hub. If you don't want to take a chance at possibly breaking a part or two, we can stop any time you want. If you follow my instructions, and for some reason break the case, I will GIVE you one.
Call Dan Benjamin for parts. P M me for the phone number. IF YOU TALK TO HIM, AND HE HELPS YOU, THEN BUY FROM HIM. IT CREATES GOOD KARMA.
Wildcat
Posts: 17
Joined: Thu Dec 28, 2023 10:08 am
Location: McPherson, KS

Re: Dempster Aunu-Oiled Rebuild

Post by Wildcat »

I’ll work on removing the hubs and let you know how that goes. Thanks for your help.
User avatar
windybob
Posts: 3878
Joined: Mon Jan 14, 2019 5:59 pm
Location: Ames Oklahoma

Re: Dempster Aunu-Oiled Rebuild

Post by windybob »

sure. anytime. I want this to be successful just as much as you. I like helping others.

Hit the hub down by the shaft. it's thick there. use a long 1/2 inch rod. I have never broken one hittin it there. And you don't have a tapered key to worry about. Things are in your favor!
Call Dan Benjamin for parts. P M me for the phone number. IF YOU TALK TO HIM, AND HE HELPS YOU, THEN BUY FROM HIM. IT CREATES GOOD KARMA.
Wildcat
Posts: 17
Joined: Thu Dec 28, 2023 10:08 am
Location: McPherson, KS

Re: Dempster Aunu-Oiled Rebuild

Post by Wildcat »

Well, I've removed the outer hub, break drum, and set screw. I'll have to make another set screw as I messed up the threads.
Break drum spring also broken. Not sure how to remove the very tight inner hub(end plate/oil seal assembly).All I've tried so far is driving wood wedges between the three flanges and tapped on the hub. Didn't want to bread the flanges. See attached photos.
You do not have the required permissions to view the files attached to this post.
User avatar
windybob
Posts: 3878
Joined: Mon Jan 14, 2019 5:59 pm
Location: Ames Oklahoma

Re: Dempster Aunu-Oiled Rebuild

Post by windybob »

well well! Great news. The setscrew is nothing. Don't need to make one, it should be a regular thread, so you can get a piece of allthread or a long-threaded bolt. The front plate is only held on with three bolts, nothing else at this point. take the 3 bolts out, and the internal spring will be pushing out on it, now that you have the setscrew out. There may be some sealer on it, but it should come out without much issue. Also, with the setscrew out, you might tap on an ear to get it to spin a little, maybe that can help get it loose. behind it is a concoughany of parts, but they should not all come flying out. You will have many questions once you get the nose plate off. Don't worry. We got this!
Call Dan Benjamin for parts. P M me for the phone number. IF YOU TALK TO HIM, AND HE HELPS YOU, THEN BUY FROM HIM. IT CREATES GOOD KARMA.
Wildcat
Posts: 17
Joined: Thu Dec 28, 2023 10:08 am
Location: McPherson, KS

Re: Dempster Aunu-Oiled Rebuild

Post by Wildcat »

Well after heating and pounding, got the end plate off. Shaft is pitted slightly as shown in the photo. All I've found behind the plate was a felt seal and corroded washer. Still can't budge the shaft. Sprayed lots more penetrating fluid and am letting it set for a while. No idea where to go from here.
You do not have the required permissions to view the files attached to this post.
mtblah
Posts: 2027
Joined: Thu Mar 26, 2020 12:09 pm
Location: new braunfels TX

Re: Dempster Aunu-Oiled Rebuild

Post by mtblah »

Inside the case , on the end of the drive shaft is a large nut, that nut holds the shaft , bearing s & spring in place
Of my memory is right there is also snap ring on that shaft
Keep patiently working on your project
It will be a great sense of accomplishment the first time you see that fan turn in the breeze
User avatar
windybob
Posts: 3878
Joined: Mon Jan 14, 2019 5:59 pm
Location: Ames Oklahoma

Re: Dempster Aunu-Oiled Rebuild

Post by windybob »

All that does not surprise me for a severely locked up Dempster. You are making progress, but slow, and that's fine. Everything you have done so far are steps in the right direction. That rusted washer is a flat tin washer that goes behind the seal (felt). inside the snout is a ring with a slot at the bottom that the setscrew went in. It's maybe 3/4 or 1 inch wide. you can run a small chisel around it and it will come loose. behind it is the outer bearing race. If I remember, you have a castle nut loose/off on the other end of the shaft. ok. Once you get that slotted collar out then the bearing will be all visible, and then we can get pretty serious about getting the rest of it apart.

Need to go in this morning for an infusion. Will be back later.
Call Dan Benjamin for parts. P M me for the phone number. IF YOU TALK TO HIM, AND HE HELPS YOU, THEN BUY FROM HIM. IT CREATES GOOD KARMA.
Post Reply