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Stevelr
02-23-2006, 06:00 PM
Anyone have any experience using variable speed DPs? (floor models)
What models would you recommend? I've looked at the new Delta's, but they have a terrible reputation for breaking. What about a used Rockwell 15" model 16-655?
Thanks
Steve

RayS
02-23-2006, 06:11 PM
Have used a clausing for years. No problems with it.

JCD
02-24-2006, 07:57 AM
If it is a Rockwell, pre Chinese, you are probably O.K. Rockwell made some nice drill presses in the U.S.

thistle
02-24-2006, 12:14 PM
I have a newer Delta drill press, too late i discovered that it was made in China and a total piece of junk .
Delta stuff went down the tubes when they started sending their stuff east to get manufactured

Stevelr
02-24-2006, 03:48 PM
Regarding the new Delta's, I have read a number of horror stories.
Check out the postings in Amazon.com Tool Crib under the listing for the bench version of their variable speed drill press.

TECHSHOP
02-24-2006, 08:55 PM
The new China Delta VS drill press have issues, is a under statement.

The earlier Tiawan made ones where "acceptable" as far as "reliablity"

The still earlier USA made Delta are pretty good, I have heard some "peace symbol" era tools may be hit or miss quality, but I would think a truely "bad machine" to have been "weeded out" to scrap or "fixed" by now.

Clausing and the USA made Powermatics (green?) are also good.

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Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

DR
02-25-2006, 05:10 AM
In my experience the variable speed DP's generally have problems with the drive mechanisms eventually. This includes the older American made models. Sometimes even when there isn't a problem the heads are noisier than I like on a DP.

Given a choice in today's world, I'd opt for a step pulley machine combined with a VFD for speed control.

Stevelr
02-25-2006, 07:51 AM
DR:

I agree noise would be a problem if the DP were a gear driven machine, but don't all the variable speed DPs use a system that relies on a belt for drive?
I've thought of the VFD option. I have one on my lathe, but there seems to be a signficant drop in torque when you go to slower motor speeds. I guess you could set a low speed with the belt/pulleys and use a high motor speed to maintain torgue. Why have the VFD at all then?
Thanks for your comments.
Steve

DR
02-25-2006, 10:03 AM
The variable speed drive I'm familiar with, like on a 20" Powermatic, uses a v-belt that's very heavy, thick and wider than a conventional one. It's noisy, vibrates if it's not run for awhile and has taken a "set" from non-use.

I also have the same setup on a 5hp milling machine head, hate it too.

Most of these type drives have an instruction sticker saying to run the machine through it's rpm range daily. Apparently to make sure the the variable sheaves don't stick in any one position. That's kind of a nuisance if you ask me.

With a VFD on a step pulley DP, you could use one of the lower speed pulley ranges and over speed the motor for the higher speeds. That might work better than having the loss of torque your're seeing when slowing the motor. A Baldor technician told me their new motors can safely be run up to 5,000rpm.

Another trick I used on a lathe with a VFD was to switch the spindle motor over to an 1150rpm model from the original 1750rpm. That gave a significant boost in low rpm torque while still allowing the high rpm turning.

Yet another trick is to go with a flux vector type VFD. These can be the sensor type with a feedback device monitoring the motor rpm or the sensorless type. Vector VFD's can operate motors near zero rpm with no loss of torque. The price has dropped so much in recent years, a sensor-less VFD can now be gotten for what a conventional VFD cost just a few years ago.

Anyway, you may have noticed I'm no fan of mechanical variable speed drives.

TECHSHOP
02-25-2006, 10:47 AM
Just to clearify my other post. When the newer China made Delta VS drillpress came on to the market the closed retail place I worked part time was replacing about 7 in 10 in the warrenty period, often a few days after they were sold. I didn't investigate the reason(s), just RTV. It may be something easy to fix, and worth a real low price to "look see."

The Tiawan Delta machine had a OSHA safety "defect" that was corrected with an additional part, had a open top above the pulleys IFRC, that limited sales to schools and such. I am reasonably sure that is a common problem with older machines.

I agree that any mechanical VS drill press is not "worry free". I think Clausing would be my first choice, new or used.

------------------
Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

JRouche
02-25-2006, 05:07 PM
I have a clausing 20" As DR said they are noisier than a step pulley drive but not any louder than my mill. She is a beast and wont slow down for anything. It also has power downfeed which comes in handy..JRouche

http://img.photobucket.com/albums/v366/Jrouche/drill.jpg

john hobdeclipe
02-25-2006, 07:40 PM
I had a Powermatic 1150 variable speed, about mid '70s vintage. After bending the spindle in a fit of abject stupidity, I replaced this drill press with a Powermatic 1150A step pulley machine. Between the two, I like the step pulley design much better...it's smoother and quieter. It works well for me, but I don't need super fine tuning of spindle speed for the stuff I do.

Both of these machines seem to be solid and well made, but the older 1150 is a bit heavier, and has a stronger base with a machined top surface.

cmiller231
02-26-2006, 07:52 PM
This past fall I was at a tool show and they had new Delta vari speed drill presses there . I pulled down the quill { great ! 6" travel}Could not believe all the side slop , I called a factory rep over to question it and the bone head said it was not that bad and to hold pressure down on the quill and it would be just fine


Chris