New router table top

[Tom Bussey]

I am finally getting around to a project I have wanted to do for a couple of years. I took the cast iron top off from an old Craftsman shaper. The large hole in the table was a 3 inch diameter hole. My largest raised panel bit was 3 1/8 in diameter so I bored the hole to 3 3/16th. Most of the Katana raised panel bits from MLCS are 3 1/8th inch diameter. There are some that are 3 1/2 inches in diameter but I do not have any of them but I have another router table that will swing them if I ever need to go that big.

I bored down to the shoulder that was existing. The casting has a boss for the opening otherwise the casting isn't thick enough. I milled a flat on the bottom and added a piece of aluminum to get the bottom of the casting I could get thickness to the same as the plate thickness on my older Woodpecker's router lift.

The pictures are of what I have now, but I will have to stick it back on the Bridgeport milling machine and a clear out a couple of ribs. I want the router lift to come up another 3/8th of an inch. Right now I can change cutters but is is a real pain. If I can get it up a little more it will be great. When I do that I am going to really check and see if I can possible drop the shoulder in the large hole down to .250 below the top surface. That will give me a little more room to drop the raise panel cutter down.

I have 5 other throat plates to turn down to fit the 3 3/16ths center hole. Also I am not sure I like all the material to the front of the table. After I build the cabinate to house the top and try it for a while I might just cut 4 inches off from the front.

I charted the holes in the router plate and made a print. The first picture is the print. The rest are just pictures of where I am at the present.

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[Tom Bussey]

Picture of the whole top.

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[Aaron Inami]

that's quite a job. Did you use a CNC mill to bore out the 3-3/16" hole? I never got into metal machining (though there was a point where I almost got a 1236 lathe). Is this going to be a larger project for building a router table cabinet?

[Keegan Shields]

Very cool! What did you have in mind for a fence?

[Mike Cutler]

Nice work!!!
I think you should give considerable thought to not removing the material in front of the cutter opening. It could come in handy some day.
There’s nothing saying that a back fence can’t be used with a router mounted in a table.
I’ve probably used a back fence just as often as the normal fence, with my shapers through the years.
Regardless, very well done.

[Tom Bussey]

To answer some questions. NO, I did not use a CNC for any of it, all manual. It already had a 3 inch hole, all I did is bore the hole out to 3 3/16ths. There was already a shoulder down to where it is now. I didn't know if I could go any deeper. But after turning it over I think I can.

I am currently making a new fence for it. It is a design than I have had in the back of my head for a longtime, about 15 years. So I started only to find out that Woodpeckers has something like it. So someone else also came up with the same concept. Any way I will have the fence how I want it. I was going to finish the fence this coming Tuesday, but I need to put it back on the milling machine and cut out a couple of ribs.

Where I work, they let me come in and use their machines on my time, so I go in on Tuesdays 7AM -12and work on my projects. I will do this until it get warm enough in my unheated shop to get back in in comfortably. Then I will be there instead of Machine Tool Engineering in Charles City Ia.

I will post more pictures here Tuesday.

I had pictures of the top and bottom getting machined but something happened to my memory stick. I will post new pictures of it happening Tuesday evening. Hopefully I will finish the fence also or at least some pictures of it as it nears completion.

Mike, I do not know what a back fence is. But a router in a table id basically the same as a Shaper in concept.

[Tom Bussey]

I gleaned up and waxed the table top today. This is what I had to do to finish it. I bored the shoulder .O81 deeper. and a couple thousandths bigger. I do not know if woodpecker still used aluminum inserts bit I had several and they all measures .250 using my micrometer. My first picture is picking up the center of the hole using my test dial indicator. Second picture is of my depth mike measuring the shoulder's depth and finding the amount the shoulder needed to drop. third is just a picture of the boring head ready to do the work.

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This is what .081 and a half thousandths looks like. and I had to put a step in the insert to fit it in the hole. Now there is no step. The first time I opened up the bore I didn't know for sure I had enough material to deepen the shoulder.

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Doing this allowed me to drop my largest diameter router bit down into the table. There is .032 clearance between th out side diameter of the bit and the wall of the table top. No room for error but I don't need an insert either.

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More to follow

[Tom Bussey]

I also had to mill out a coupe of small ribs. I had to turn it a couple of time to remove only what needed to be removed. I also got all of the woodpeckers inserts turned down to fit my opening, The fits are drop in so there is now way they will come out so I do not have to fasten them in gravity will hold them there.

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And because I removed a couple of small ribs it allows me to to be able to raise the router about 3/8ths if an inch more than before. Now I can do above the table top tool changes. The handle ( bar ) in the pictures is the quick like raise or lower wrench. When I raise it it also lifts the insert out of the top. I keep getting the wrong picture.

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I already know I will have to make the opening in a couple of inserts bigger but not by much so this kind of brings the conversion a 1/2 HP shaper top to a 3 1/4 HP router table top. I still need to mak a cabinate to put it on but I will have to wait until spring when it warms up to even start it.

I hope you enjoyed seeing this unfold.

[Bruce Page]

It is handy having the Bridgeport in the shop isn’t it. I’m doing a little downsizing and sold my Bridgeport right angle head and BP boring head this week on CL. I hope I don’t regret it down the road.
The table looks great.

[Aaron Inami]

Very nice. I never got into milling, but I am assuming there's a special process for turning the cranks so that the small cutter will bore a perfect hole.

[Wes Grass]

Yes. Its known as 'CNC' ;-)

There are a couple ways I've used for holes too big for the boring heads we had. One is to use a larger end mill, like 3/4", and trig out a bunch of coordinates at some angle, 5 or 10 deg. And then crank them all out. It results in a scalloped bore, but sometimes that's good enough. Or at least saves a bunch of time for the next method.

The other is a fly cutter. And hand adjusting the tool for the diameter you want by offsetting the table half the dia, and setting the tool to touch by feel. A good touch can hold a thou or so. Just have to remember to reset the table to 'zero' before making the next cut, or improper language can result.

[Tom Bussey]

Wes,
I understand what you are trying to say. And yes, you could do a large hole that way. But if you went every nine degrees you would have 40 X-Y positions. You would have to have a Digital read out I would never do it that way. and I can also understand the fly cutter concept, but that is a last resort if one didn't have a boring head. If I needed a hole larger than my boring head would do, I would just put in the Bridgeport boring head, which is bigger. And if I needed it larger than that I would put it on a rotary table.
I do not understand why you even wrote your response. Most people here on the forum can't trig anything out and that kind of work isn't done in my profession. And just so you know. Length of radius times the sine is the length of side opposite, and the radius times the cosign is the length of side adjacent.

[Wes Grass]

Every place I've worked was limited on the capacity of tooling. So you learn to improvise. Yes, cranking out all those 'holes' with dials is mind numbing. But with the DRO I have you just crank to zero as a bolt pattern. Harder to screw up, but just as tedious.

A rotary table with a piece the size of yours would also be a problem in the average shop. I heard somewhere of a RT being clamped to the bed of a lathe behind a Bridgeport, and the turret being swung around to it.

I dont work with anything that big, and never will.

I can think of plenty of other methods I've heard of that are even more bizarre.

Nice project, BTW.