drill press for pp or semi-pp
03-18-2008, 10:35 AM
#1
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Thread Starter
Join Date: Feb 2005
Location: Kissimmee FL.
Posts: 1,579
wich model/brand do you reccomend or use to cut out your pp or semi-pp???
i was looking at a bunch of floor models. but they might be an over kill. and some of the bench tops look real nice and can save some space. but do they have the power? and can you even fit a housing in there?
what do you use???
i was looking at a bunch of floor models. but they might be an over kill. and some of the bench tops look real nice and can save some space. but do they have the power? and can you even fit a housing in there?
what do you use???
03-18-2008, 10:44 AM
#2
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Join Date: May 2003
Location: Albany, NY
Posts: 72
I picked up a combination horizontal/vertical mill from the 50's and I'm gonna use that. It's a little more accurate than a drill press. It's a big hommer of a thing, and takes up a lot of space. It's got about 10hp.
Originally Posted by sen2two' post='896736' date='Mar 18 2008, 07:35 AM
wich model/brand do you reccomend or use to cut out your pp or semi-pp???
i was looking at a bunch of floor models. but they might be an over kill. and some of the bench tops look real nice and can save some space. but do they have the power? and can you even fit a housing in there?
what do you use???
i was looking at a bunch of floor models. but they might be an over kill. and some of the bench tops look real nice and can save some space. but do they have the power? and can you even fit a housing in there?
what do you use???
03-18-2008, 11:46 PM
#5
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Location: Savannah, Ga
Posts: 2,763
In all honesty, I wouldnt trust the accuracy of a drill press for boring PP's. Drill presses are designed for straight drilling with no side loading of the bit. Thats all fine for the initial part of the cut, but once you get to the face of the rotor housing, you will have part of of the port being cut all the way through before the rest. It will be hard to maintain accuracy in the port with a hole saw during the last bit through the housing face. And if you plan on using an interference fit aluminum sleeve, you will have to have the hole bored anyways, which you cant do with a drill press. Its just not rigid enough.
I just got that milling machine this month, previously I had a jig used to hold a rotor housing on my lathe. That is certainly a cheaper option for getting the rigidity necessary for boring, but you will still need a jig as well as a way to hold the boring bar in the lathe head. Ill get a pic of that jig if you are interested.
Id like to see someone prove me wrong and come up with a cost effective way to bore out PP's, but I have yet to see anyone successfully do it without at least a lathe and a jig. I think the rigidity required to bore the hole to an acceptable tolerance is not attainable without specialized machinery, be it a lathe with a jig to put the housing on the table, or a milling machine.
I just got that milling machine this month, previously I had a jig used to hold a rotor housing on my lathe. That is certainly a cheaper option for getting the rigidity necessary for boring, but you will still need a jig as well as a way to hold the boring bar in the lathe head. Ill get a pic of that jig if you are interested.
Id like to see someone prove me wrong and come up with a cost effective way to bore out PP's, but I have yet to see anyone successfully do it without at least a lathe and a jig. I think the rigidity required to bore the hole to an acceptable tolerance is not attainable without specialized machinery, be it a lathe with a jig to put the housing on the table, or a milling machine.
03-19-2008, 07:44 AM
#6
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Join Date: Jun 2004
Posts: 524
Drill presses are better than hand drills in that you can put more load on the bit. It's amazing how you can use a hand drill and do nothing but burn the bit up 'cos it's not cutting, then put it all in a drill press and REEF on the handle (I mean, pull the handle gently in a sane and responsible manner) and it cuts like butter.
But they are not accurate. They have weenie spindle bearings and the bit can walk all over the place.
Mills on the other hand have big huge beefy bearings and thick shafting and precision bedplates and they will put the hole exactly where you want it to be, or at least they will put it exactly where you set the machine up to put it. (Oops!)
I've used a drill press before and it took a lot of setup time and it was still not very accurate.
But they are not accurate. They have weenie spindle bearings and the bit can walk all over the place.
Mills on the other hand have big huge beefy bearings and thick shafting and precision bedplates and they will put the hole exactly where you want it to be, or at least they will put it exactly where you set the machine up to put it. (Oops!)
I've used a drill press before and it took a lot of setup time and it was still not very accurate.
03-19-2008, 07:59 AM
#7
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Join Date: May 2003
Location: Albany, NY
Posts: 72
the sideloading thing is why I bought mine... I also use it for making 3mm slots in rotors, and lots of other things... I got mine off ebay for $500. I have a drill press too but I would not do the pp on it. I'll try to find pictures of it tonight. The only issue I have is that it's huge, and takes 3phase, so I had to get a converter.
03-20-2008, 01:00 AM
#10
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Join Date: May 2002
Location: California
Posts: 22,465
Originally Posted by heretic' post='896816' date='Mar 19 2008, 04:35 PM
But ports are like the Internet. They aren't trucks, they are a series of tubes.
And tubes are round, so you have to make a round hole.
I learned that lesson the hard way.
And tubes are round, so you have to make a round hole.
I learned that lesson the hard way.
yeah true, i guess the port opening is the only real not round bit