Rebuilding Dempster 10 ft no 12

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jjgag
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Joined: Sun Jun 23, 2024 11:28 pm
Location: Washington State, south king county

Rebuilding Dempster 10 ft no 12

Post by jjgag »

So I started to tear my Dempster 10ft no12 down tonight. In reading other post by Windy Bob he mentioned cutting the pins before you can unscrew the rods. Is this the two pins? Looks like someone just penned them over. If I cut them can I buy replacementss.

Next question. Do I start a new post every time I have a question about this rebuild or do I just ad to this thread what does the group prefer?
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Last edited by jjgag on Thu Jun 27, 2024 8:42 am, edited 1 time in total.
mtblah
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Location: new braunfels TX

Re: Rebuilding Dempster 12

Post by mtblah »

just keep adding to this thread , also your photos are great .
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windybob
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Re: Rebuilding Dempster 10 ft no 12

Post by windybob »

If the shaft is free, and working, then just grind off the pins, knock them out and remove the crosshead shaft. You can use almost any kind of pin to go back together with. Those pins are rather stress free.
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.
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windybob
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Re: Rebuilding Dempster 10 ft no 12

Post by windybob »

then you can loosen the setscrews to the guide rods tie (cast top part) by tapping under it gently with a hammer. ( small one required here. Big one required later ) Knock the guide rod lovknuts loose and then unscrew those. Take the bolt from the big gear shaft tie down bar out, and the crank gears will lift out.
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.
mtblah
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Joined: Thu Mar 26, 2020 12:09 pm
Location: new braunfels TX

Re: Rebuilding Dempster 10 ft no 12

Post by mtblah »

yes they will .
jjgag
Posts: 16
Joined: Sun Jun 23, 2024 11:28 pm
Location: Washington State, south king county

Re: Rebuilding Dempster 10 ft no 12

Post by jjgag »

Okay I gutted it and got the bull gears out. I took the nut off the wheel or sail end off the shaft and found the dreaded keyway. Now I need help getting the hubs off. Does the outer hub separate from the inner hub (brake hub) or pull it as one assembly?
There are three bolts that the main tube that bolt to the brake hub and one larger bolt that holds the brake together.
What should be my next course of action?
Last edited by jjgag on Thu Jun 27, 2024 9:09 pm, edited 1 time in total.
jjgag
Posts: 16
Joined: Sun Jun 23, 2024 11:28 pm
Location: Washington State, south king county

Re: Rebuilding Dempster 10 ft no 12

Post by jjgag »

Sorry you all need photos
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windybob
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Re: Rebuilding Dempster 10 ft no 12

Post by windybob »

Dempster uses tapered keys. unless the key is loose enough to slide on the shaft ( the flat side) it will not slide on the hub side ( tapered side).

I will speak from working on 8 ft mills. Never had a 10 ft, but I will assume ( at my risk) they are very similar.

UNder the front of the snout, there is sometimes a slotted setscrew with a nut. I do not see one here, so I presume you have a full-circle rubber oil seal which is the later improvement over the older felt seal. If you can see that oil seal in the front plate of the snout, thats good. There are 3 or 4 bolts that hold the front plate on the snout. Take those out. Also remove the cotter key that is through the castle nut on the end of the shaft next to the pinion. UNscrew the nut. In a perfect world, the hubs, shaft, and front plate should come out. The gears and spacers etc will be left behind. Looks like things are oiled up pretty good, so we'll see what happens. Keep in mind, the front plate may be glue (sealed) on the snout, so might try to seperate it from the snout. Sometimes if put a wedge or spacer between the castle nut and the inside of the case, as you unscrew the nut off the shaft, it can help push the works out the front.
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.
jjgag
Posts: 16
Joined: Sun Jun 23, 2024 11:28 pm
Location: Washington State, south king county

Re: Rebuilding Dempster 10 ft no 12

Post by jjgag »

Thank you Windy. I did see a rubber type washer looking item between the main tube and the brake hub. I appreciate the response. Now I have to wait 10 hours for work to end and I can start back on it.
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windybob
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Re: Rebuilding Dempster 10 ft no 12

Post by windybob »

Remember, NO hurry. Keep me posted. Hope all the info fits a 10 footer. We have a high water table here, so larger mills are not to be found, except if they are for decoration.
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.
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