Dunlap drill press questions
Dunlap drill press questions
Hey guys, new to the forum. I recently got a dunlap 103.23620 from my brother in very good cosmetic condition with a few little mechanical gremlins. It needs a good cleaning and oiling mainly.
My questions that I have pertain to the spindle pulley. Ive seen some pictures online that show the upper brass bushing that's pressed into the headstock sticks out about an 1/8". The pulley then rests on this surface on a thrust washer that's (supposed to be) pressed into the bottom of the pulley. Here are my questions:
1. What keeps this brass bushing from sliding down in the bore if the drill press is over extended?
2. My pulley is missing the pressed in thrust washer. Is this thrust washer steel or is it some sort of brass? Looking to make one and press it in.
3. There's a hole cast into the bushing housing. I'm assuming an oil hole, but oddly the hole goes to nowhere. There's not even a hole is the brass bushing, should there be?
If pictures are needed please ask.
Thank you.
My questions that I have pertain to the spindle pulley. Ive seen some pictures online that show the upper brass bushing that's pressed into the headstock sticks out about an 1/8". The pulley then rests on this surface on a thrust washer that's (supposed to be) pressed into the bottom of the pulley. Here are my questions:
1. What keeps this brass bushing from sliding down in the bore if the drill press is over extended?
2. My pulley is missing the pressed in thrust washer. Is this thrust washer steel or is it some sort of brass? Looking to make one and press it in.
3. There's a hole cast into the bushing housing. I'm assuming an oil hole, but oddly the hole goes to nowhere. There's not even a hole is the brass bushing, should there be?
If pictures are needed please ask.
Thank you.
Re: Dunlap drill press questions
Pictures would help, for sure.
One question. Do you know, for sure, that your description of things is correct? Don't assume a bearing must be press fit, as it may not be.
Welcome to the board!
Harold
One question. Do you know, for sure, that your description of things is correct? Don't assume a bearing must be press fit, as it may not be.
Welcome to the board!
Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
Re: Dunlap drill press questions
You were already welcomed by the best but I will do it anyway. Welcome!
The same goes with drill presses. Dunlap has a pretty long rocky history with Sears tools but that # 103 is supposed to mean ; King Seeley Corp. Good stuff. Not industrial but we dig a drill press. A wonderful essential tool. Things wear more and lubrication is essential with sleeve bearings. Since you already investigated that blind hole, it may be that bearing/ sleeve was already replaced. Clean and look at that hole. If there is any vestige of threads, then it was an oil port. That may mean it has porous bronze sleeve bearing which could absorb the oil in that pocket, if it was closed by a short set screw. The big other thing is the spindle drive key/slot. That needs lube or light grease or wears to unacceptable nub.
Yes pics. We know it must have thrust bearings of brass or bronze. Different types
The same goes with drill presses. Dunlap has a pretty long rocky history with Sears tools but that # 103 is supposed to mean ; King Seeley Corp. Good stuff. Not industrial but we dig a drill press. A wonderful essential tool. Things wear more and lubrication is essential with sleeve bearings. Since you already investigated that blind hole, it may be that bearing/ sleeve was already replaced. Clean and look at that hole. If there is any vestige of threads, then it was an oil port. That may mean it has porous bronze sleeve bearing which could absorb the oil in that pocket, if it was closed by a short set screw. The big other thing is the spindle drive key/slot. That needs lube or light grease or wears to unacceptable nub.
Yes pics. We know it must have thrust bearings of brass or bronze. Different types
Re: Dunlap drill press questions
Thanks for the welcome guys. This drill press is by no means industrial but perfect for my little home workshop. It's very tight with little wear and tear or slop in any bearings/pulleys. So it leads me to believe that this bronze bushing/bearing is original therefore confirming the possibility of it being porous and allowing the oil in slowly and when needed. The hole in the cast isn't threaded. According to a manual for this drill press it says to use 30 weight motor oil throughout the system so it's definitely possible.
As for my questions here are some pictures that should help explain them. The underside of the pulley should have a thrust washer pressed into the face of it which rides on top of the bronze bushing which is pressed into the headstock.
When I took the drill press apart that bronze bushing was flush with the surface of the cast iron. You can see wear marks on the underside of the pulley where it rubbed on the cast iron. I used a socket to tap the bushing up to where it's shown in that pic. My worry is that if I'm able to tap the bushing up, that the feed handle of the drill press is able to push it back down if the feed handle is over extended. I don't plan on overextending it but you never know.
Thank you,
Matt
As for my questions here are some pictures that should help explain them. The underside of the pulley should have a thrust washer pressed into the face of it which rides on top of the bronze bushing which is pressed into the headstock.
When I took the drill press apart that bronze bushing was flush with the surface of the cast iron. You can see wear marks on the underside of the pulley where it rubbed on the cast iron. I used a socket to tap the bushing up to where it's shown in that pic. My worry is that if I'm able to tap the bushing up, that the feed handle of the drill press is able to push it back down if the feed handle is over extended. I don't plan on overextending it but you never know.
Thank you,
Matt
Re: Dunlap drill press questions
I'm no fan of adding poor and less than well thought out permanent additions to any machine tool and it does destroy it's collector value. But everything is designed and built to match a selling point. Good well thought out improvements by the owner can make a so-so machine tool into something a lot better than the condition it left the factory in. From what I've seen adding a couple of proper hardened and ground thrust washers and the same for a thrust bearing would just make the factory OEM design a lot better. Might take some remachining to get surfaces back to being square and the correct size to the shaft to do it.
I hadn't known the Dunlap drill presses were sold by Sears, but your first post with that number seems to always indicate something sold by them. Sears in the U.S. did or maybe still does have a great number of exploded views of all the parts for items once sold by them. They did or still do have even some limited parts availability for the Atlas horizontal mills. It's not impossible they might still have a few for your drill press, or at least that exploded view for what was there originaly. It's been some years since I last checked there parts drawings though. Going to a Sears webite after Googleing for Sears replacement parts and then plugging your Drill Presses part number into that should bring up anything they still might have.
That hole isn't tapered is it? If so it wouldn't be much. But if it was drilled at the factory as well as part way into that sleeve bearing and then taper reamed a taper pin might have been used to hold that sleeve bearing in place. If the bearing was replaced at some point that person may not have bothered to redrill the bearing and reuse the taper pin. Only guessing at this point about that. But taper pins were pretty common on equipment of that vintage.
I hadn't known the Dunlap drill presses were sold by Sears, but your first post with that number seems to always indicate something sold by them. Sears in the U.S. did or maybe still does have a great number of exploded views of all the parts for items once sold by them. They did or still do have even some limited parts availability for the Atlas horizontal mills. It's not impossible they might still have a few for your drill press, or at least that exploded view for what was there originaly. It's been some years since I last checked there parts drawings though. Going to a Sears webite after Googleing for Sears replacement parts and then plugging your Drill Presses part number into that should bring up anything they still might have.
That hole isn't tapered is it? If so it wouldn't be much. But if it was drilled at the factory as well as part way into that sleeve bearing and then taper reamed a taper pin might have been used to hold that sleeve bearing in place. If the bearing was replaced at some point that person may not have bothered to redrill the bearing and reuse the taper pin. Only guessing at this point about that. But taper pins were pretty common on equipment of that vintage.
Re: Dunlap drill press questions
One thought occurred to me, assuming I understand the bushing problem. If it is capable of being displaced by the spindle, a fast and easy fix would be to replace it with a shouldered bushing, which would prevent it from being pushed deeper in the cavity.
Harold
Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
Re: Dunlap drill press questions
Pete, I do have a copy of the original manual for this machine. The exploded view doesn't show any type of pin that would secure the bearing in place.
Harold, I too though of having a bushing made with a shoulder on it however, the shoulder would rub on the two flats of the underside of the pulley where the thrust washer goes. I think for the time being I'm going to remake a thrust washer for it and reassemble and keep an eye on everything if it doesnt move then the problem is solved.
Still curious about that oil hole and the fact there is no thru hole. I'd love to hear from someone that has one of these units it has taken one apart.
Just so everyone understands, this is a pic of the same pulley with the thrust washer installed. You can actually see where the pulley rests on the bronze bushing.
Thanks again!
Harold, I too though of having a bushing made with a shoulder on it however, the shoulder would rub on the two flats of the underside of the pulley where the thrust washer goes. I think for the time being I'm going to remake a thrust washer for it and reassemble and keep an eye on everything if it doesnt move then the problem is solved.
Still curious about that oil hole and the fact there is no thru hole. I'd love to hear from someone that has one of these units it has taken one apart.
Just so everyone understands, this is a pic of the same pulley with the thrust washer installed. You can actually see where the pulley rests on the bronze bushing.
Thanks again!
Re: Dunlap drill press questions
That oil hole in the bearing boss would allow oil to gravitate through the porous bronze. What I don't understand is radial support for the stack pulley. It appears that the belt pressure is bearing directly upon the that upper sleeve bearing and the spindle shaft. I guess that is the radial support.. So then, yes to what Harold said. A flanged piece atop the sleeve bearing to allow it to sink to its depth and only slightly flanged at the top, so it rides inside those flats.
Re: Dunlap drill press questions
Best guess is the shaft would be a standard size. If so straight and flanged oilite bushings are a standard over the counter item. Oilite bushings if there not seriously worn can also be recharged with oil simply by blocking the bottom off with a finger, filling to the brim with oil and trying to compress the oil at the top with your thumb. That's guessing the bushing has a small enough ID to block the holes off with normal sized fingers. If it works you should see oil weeping out through the porous bronze on the OD. Thick oil like 90 wt gear oil is far too thick to use and the sulpher in it can react with some alloys of bearing bronze.
Re: Dunlap drill press questions
I found info at Vintage Machinery and that is the very cool design from King Seeley. I think a proper spacer is all that is needed now. I didn't realize how it worked at first. The actual spindle is 6 splines and is in a quill tube. The bearing in question, doesn't bear onto the actual spindle. it bears on the quill tube and the only problem is that small area between the driven pulley and the top. Cool drill press and I got to thinking about my Craftsman at the right of a bench. It isn't styled like yours but the head casting is 103 11407. It is also 6 spline drive and works the same way. This one has been a good drill press too.
Re: Dunlap drill press questions
I really looked but there is no Sears emblem/plate on mine. The table is more a practical build with troughs within the outer edges. This is the type with a full metal cover and there is a tall section above the spindle. It also appears the head casting is shorter but appears a ball bearing at the top. Whatever; I never did more than oil it and put a reverse switch on the motor (for LH drilling).
Re: Dunlap drill press questions
spro thanks for the info. Glad I didn't go ahead and just drill a hole in the bushing. The only thing I am worried about, which i mentioned before, is if the drill press arm is over extended and forced down. A positive stop like Pete mentioned would definitely eliminate the possibility of that happening. One thing that u thought of doing was pulling the bushing out and maybe cutting some sort of retaining ring groove in it and using a retaining ring as a shoulder. Or even if it's a shallow groove, I could use a wire, kind of like a piston circlip. Where the circlip would sit is in a beveled groove so it would wedge into place and never move. This would be my last resort if the bearing happens to slide down after use.
I'm going to test the bearing by pressurizing the oil fill hole slightly. That's a good idea.
I'm going to test the bearing by pressurizing the oil fill hole slightly. That's a good idea.