Mill drill versus drill press? Drill press runout?

[Highpower]

You'd need a JT reamer to clean up your drill press taper. They're scarce to non-existent:
http://bbs.homeshopmachinist.net/showthread.php?t=29290

John

Ummmm..... http://www.mcmaster.com/#reamers/=hj56bu

[jgourlay]

Magpie, from somewhere else on this board I found the Houston area club's details. So I'll get involved there!

Funny you should mention CL. Just this weekend I saw an add for a 1972 Delta DP that looks very suspiciously like the one I had. So close, in fact, that I wouldn't be surprised if what delta did in the early 2000's was to send the blueprints to their chinese factory. Hmmm...

What you said is so true. I paid top dollar for this thinking I'd never have to mess with it. This was the first 'machine' I ever bought, and was bought in fair state of ignorance. It had .005" runout from day one. I thought, at the time, that was normal.

18 or so months after purchase, I took a new job at a company that had a 1940's vintage Drill press. The machinist chucked up a peice of 1/2" turned bar stock in it and a dial indicator for me. Runout was.... .000", with just a barely perceptible wiggle. But...mine was good enough for woodworking.

I just never figured I'd ever be in a position where I'd have to rip the guts out of it. Wife wants a new entertainment center, and new wooden stairs, and hardwood flooring instead of carpet upstairs. Christmas is coming. But I'm sure you understand how intolerable it is to allow a broken machine to compost for months in the shop, unfixed.

Find a local metalworking club in your area. Or find a member here who lives close to you. (It would be helpful to post your location.) Borrow a Morse taper reamer to clean up your spindle taper. It shouldn't be a Jacobs taper unless the spindle has a male taper on the end, in which case it's easy to stone off a burr.

It isn't impossible to stone off a burr on a female taper either, just need a round stone.

If your Delta is one of the old ones from the '30s, '40s or '50s then it might be worth keeping. Once the name got sold to China you're just buying garbage and their "gold plated best" model is still just garbage. There is a place for cheap machines that are a misery to use but not a drill press that gets used all the time. I might watch your local craigslist for a decent deal on an '80s or '90s Taiwanese DP. Perhaps the best of those was the Jet 17-MF. Those generally worked OK. Have a look at this:

http://www.tinyisland.com/htbdrillp.txt

Though it was written in 1998 it seems to be still applicable.

metalmagpie

[jgourlay]

High Power,

Thanks but I probably wasn't clear. The DP spindle has a *MALE* Jacobs Taper 33 sticking out of it.

Ummmm..... http://www.mcmaster.com/#reamers/=hj56bu

[gwilson]

If it has a MALE #33 taper,just carefully file off the high spots caused by the gouge. Don't get carried away,just carefully eliminate the high spots. The accuracy will not be affected if you don't file all over the taper.

I also suggest getting a decent chuck. I had a Delta Asian made drill press at work with the same problem runout. I put a real Jacobs chuck on it,and the drill press ran quite true. The Asian chucks are never very accurate.

[Paul Alciatore]

So, in the 'homeshop', what do most people do when they need to pop a hole in the end of a piece of wood or barstock that is tool long for the lathe (or two fat to feed-through)?

Do most folks have both DP and Mill?

I suspect that most here do have both a drill press and a mill. I do and hope to get a second drill press in the future. But, that may not be you.

As for drilling the end of bar or other long stock, yes some mill-drills can have the head rotated about their ROUND column to a position where this can be done off the edge of the table. However, no manufacturer does or will provide a guarantee of this ability in the specs. At least, I have never seen it and I have read a lot of them. Unfortunately even asking their sales personnel about this may not bring accurate answers. If you plan to go this route, I would advise you to check out the machine in person before purchase. Clamping it would still be a problem.

As for your concerns about the quality of a mill-drill, I have purchased and used two import models, both from Grizzly. There was some set up time as you would expect, but both did work as delivered and I was not disappointed in their rigidity. Accessories are needed: vise, clamp sets, collets, etc.

If I were faced with such a job, I would probably use the lathe. If the stock is small and you only need a axial hole in the end, the stock can be passed through the headstock and drilled with a drill chucked in the tail stock. But I assume you already know that. That is the easy way. Caution, if you do it this way, be sure to restrain long stock as it can bend and whip about the shop if it is more than a foot or two out of the rear of the headstock.

For larger stock and off center holes I have a milling table that I made for my SB lathe that allows long stock to be clamped horizontally.



Although this photo does not show it, with this table I can drill or mill features of almost any description on the ends of long stock. Some outboard support may be needed. A more conventional, vise type milling attachment for the lathe would also allow such work to be done. Of course, the down side is longer set up time and it is definitely on the light duty side for milling. On the plus side, the length of such stock is only limited by the walls of your shop, not the distance to the floor.

[jgourlay]

Thanks, I'll do as you suggest.

If it has a MALE #33 taper,just carefully file off the high spots caused by the gouge. Don't get carried away,just carefully eliminate the high spots. The accuracy will not be affected if you don't file all over the taper.

I also suggest getting a decent chuck. I had a Delta Asian made drill press at work with the same problem runout. I put a real Jacobs chuck on it,and the drill press ran quite true. The Asian chucks are never very accurate.

[PaulT]

High Power,

Thanks but I probably wasn't clear. The DP spindle has a *MALE* Jacobs Taper 33 sticking out of it.

Its very likely that you are just seeing the chuck end of a dual end tapered arbor that is inserted into the drill press spindle, the spindle likely has a female MT taper.

Take a close look to see if there is a split line visible. If so you could remove and replace that arbor. If its been stuck in there for a long time it may require a soak with something like Kroil and then some heat to help loosen it up.

Paul T.
www.power-t.com

[jgourlay]

Paul, thanks.

I do so wish that was the case. I have confirmed on the parts list exploded drawing that it's a JT machined into the spindle.

[dian]

a bt whatever taper machined onto a spindle:

http://i973.photobucket.com/albums/a...ndian/x075.jpg

[Gary Paine]

Paul, thanks.

I do so wish that was the case. I have confirmed on the parts list exploded drawing that it's a JT machined into the spindle.

If you have a steady rest, a 4 jaw and a good dial indicator, and if you have the spindle out of the DP, it is a fairly easy matter to check the taper for truth in your lathe. By doing that first, you can assure yourself whether you need to spend money on a replacement chuck. If you find any runout, or if the taper didn't stone to satisfaction, you can take very light cuts to get the taper clean and running true in the same setup. Without disturbing the setup, you can then reattach the chuck and measure it's runout as well. I've done this subsequent to straightening a DP spindle with excellent results.

If the DP is not disassembled, you can still check your stoning work on the taper using an indicator to measure radial runout.

Also helpful is the use of Dykem or similar marking fluid applied to the chuck inside taper. It will transfer to the spindle taper at the high points and show you where to remove material to get the fit right. Although this hand fitting will result in a good fit, it will not always correct inherent runout like the lathe would.