Bridgeport Quality

I bought my Bridgeport mill new in 1981. Today I just finished power tapping a bunch of 5/16-18 through holes in .5 thick 7075 aluminum.
With the mill in low range at 250 RPM. I just put the tap in the drill chuck, turn the spindle on forward till the tap is through and then plug reverse the motor and back the tap out. I can't even begin to count how many holes I have tapped this way on this machine. I have never overheated the motor or switch gear and they are still original. The motor has the "tropical insulation" in it so I guess that means it can stand hot humid running. I don't know if a new Bridgeport today would hold up as well, I hope they would. I do know of more than one import mill that has cooked a motor and/or the switch gear. Eric
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I came across a pallet of five burned Excello motors.

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Remember motors can be rebuilt. Sometimes the fix or frame is worth the trouble.
The newer wire has better insulation (higher voltage and life) making the total wire smaller - and the whole winding fits in nicely. Only better.
I used to know a motor repair man. He did a large business on custom housings that only came with this machine from the factory.....
I was helping him with the burnout oven design.
Martin
On 4/14/2015 9:14 PM, Ignoramus7898 wrote:

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On Tue, 14 Apr 2015 21:14:10 -0500, Ignoramus7898

I'm not surprised. I have ran Excello mills and hate them. But I know folks who love them and think they are the best. Eric
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CNC is little help without a CAD file, which you don't have when making repair parts.
Segway's experimental parts were mostly made manually, cut-to-fit, on a CNC Bridgeport and lathe. I rarely saw them running CNC files, usually an engineer was working from a sketch and inventing the part on the fly.
The files that castings had been made from didn't help without the production machining fixtures to position them. I had to reconstruct their hole patterns relative to locatable reference features, then locate and center-punch new holes with a height gauge and dividers while they weren't stressed by clamping. Thin-walled plastic injection moldings were particularly difficult to clamp securely enough without distorting them.
Expensive CAD seats were in heavy demand. The only one I could borrow was for the powerful but quirky circuit board design program which didn't talk to SolidWorks or the milling machine. It was quicker to just manually mill a one-time part from the drawing while the machine was free than to manually translate and enter the G code.
There was a considerable speed advantage in being able to make non-production stuff in-house rather than cleaning up the drawing enough to send it out.
-jsw
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