Today in the shop (powerpro routing)

[ryanbp01]

At the risk of sounding stupid, what is the difference between under table routing and using the overarm pin router? The reason I ask this is to become better informed about doing a possible Power-Pro conversion.

BPR

[JPG]

At the risk of sounding stupid, what is the difference between under table routing and using the overarm pin router? The reason I ask this is to become better informed about doing a possible Power-Pro conversion.

BPR

Location of router/motor/bit.

Location of pin.

[SDSSmith]

At the risk of sounding stupid, what is the difference between under table routing and using the overarm pin router? The reason I ask this is to become better informed about doing a possible Power-Pro conversion.

BPR

I would say one major difference is the reference surface. For under table routing the reference surface is the same as the surface being routed. Just the opposite in over arm or above table routing.

[fjimp]

For me it is preference. As I age I find I am more comfortable being able to track cutting blades. Below table limits my view. Jim

[heathicus]

Reible, I learn something every time I read your posts. Thanks for sharing your knowledge!

[reible]

If front rear 'adjustment' is needed, a counterbored slot(and cap screw) with flat bottoms would work better than a tapered counter sink. May have to grind down the head to minimize height.

Lack of material thickness(insert) may make it impractical.

I wanted to use the same screws as all table inserts.

In fact my guess about how close the flipped table would align was with in about a 1/4" so my choice to make the slots this dimension was flawed.

The alignment is really two parts, the in and out or carriage adjustment is never going to be an issue. The left/right location has no adjustment except for the bolts that hold the table on. But it makes no sense to change your alignment just to use an insert. The slots on the table insert sounded like the way to go and had I done a better job of it would have been fine.

The process I used to locate the hole was to fit the insert in the table and then use a 1/16" drill bit to drill a through hole. I started by drawing a center line on the insert and using that for the starting of the process. I was set up in the motor below router position shown here when I drilled the hole.

[ATTACH]19255[/ATTACH]

I then rotated the table to the router above (drill press) position. When I compared he hole position with the location of the bit it was actually about lined up with the edge of the hole. This could have been more like 1/32" difference, far closer then I ever expected.

[ATTACH]19256[/ATTACH]

By this time the slots had been done so there was no going back. I loosened the screws and move the insert to align with the bit and tighten in place to start the drilling process. A slightly over-sized hole would have worked in this case so long as it would hold the insert in place.

Ed

[reible]

As always Ed, well thought out and well executed. Thank you for sharing. I am curious about the larger template guides, who makes them and where did you get them?

Sadly the place I was able to get the template guide in 1/16" steps will be going away soon. They have some brass left on clearance until the first of the year when they close up operations.

http://www.oak-park.com

A second source is lee valley but they do not have as many sizes as oak-park use to. The template guide in 1/16" steps can be use to do a pass at one size larger then finished size then switch for a finial finished cut. Since you use only 1/2 the template dia. that equates to doing a 1/32" final pass.... sweet.

The oak-park set was/is not cheap, they use to list for I believe $12.95 ea, about $3 less when I last looked.

Ed

[reible]

At the risk of sounding stupid, what is the difference between under table routing and using the overarm pin router? The reason I ask this is to become better informed about doing a possible Power-Pro conversion.

BPR

It looks like you have your answer in previous posts but I want to cover one more thing for you so you can make an informed choice if and when required.

The shopsmith can be used as a overhead or as a below the table router. It is not a pin router. Yes it has some of the aspects but lack an extremely important detail, that is the ability to lock the depth with the handle. On an OPR the lever that allows for the vertical movement also twists, the twist lock and unlocks the depth. The shopsmith would require you to have a third arm to do the locking... I'm guessing you don't have a third arm.

If you want the pin router option you will want to direct funds for that, other funds for the shopsmith dual tilt and powerpro for a below the table router function.

Ed

[dusty]

I wanted to use the same screws as all table inserts.

In fact my guess about how close the flipped table would align was with in about a 1/4" so my choice to make the slots this dimension was flawed.

The alignment is really two parts, the in and out or carriage adjustment is never going to be an issue. The left/right location has no adjustment except for the bolts that hold the table on. But it makes no sense to change your alignment just to use an insert. The slots on the table insert sounded like the way to go and had I done a better job of it would have been fine.

The process I used to locate the hole was to fit the insert in the table and then use a 1/16" drill bit to drill a through hole. I started by drawing a center line on the insert and using that for the starting of the process. I was set up in the motor below router position shown here when I drilled the hole.

[ATTACH]19255[/ATTACH]

I then rotated the table to the router above (drill press) position. When I compared he hole position with the location of the bit it was actually about lined up with the edge of the hole. This could have been more like 1/32" difference, far closer then I ever expected.

[ATTACH]19256[/ATTACH]

By this time the slots had been done so there was no going back. I loosened the screws and move the insert to align with the bit and tighten in place to start the drilling process. A slightly over-sized hole would have worked in this case so long as it would hold the insert in place.

Ed

This is very interesting and I think impressive. It leads me to conclude that the main drive line is located precisely on the centerline between the main table uprights. One could also conclude that there is no slop in your drill chuck. There also can be no slop in the carriage when locked in position.

Like I said, I am impressed.

Just wondering, Ed. Did you enlarge the mounting holes in your trunnions. My guess is that you did not. For those of us that did, achieving this degree of alignment would be a bit more difficult.

HOWEVER, it seems like you could loosen the trunnions bolts and reposition the table such that it would align perfectly in both configurations.

[algale]

When I went to setup I knew the tie bar guard would have to come off, same if you want to use the drum sander from below. That is just 2 fasteners and only takes seconds but it has to be done.

Ed,

Thanks for the tutorial. It makes perfect sense the tie bar guard has to come off for this under table operation but is that spelled out in the instructions for the double tilt upgrade? (Any Mark 7 owners care to comment on whether it is part of the Mark 7 instructions?)

My other question is whether you will be reinstalling the tie bar guard for normal operations (say table saw)? And, if not, can you let us know whether you notice any degradation in dust collection efficiency without the tie bar guard. I find I am constantly catching the tie bar guard on the lower blade guard when setting up for sawing operations and I would love to do away with it in its entirety if it doesn't degrade dust collection performance significantly.

Al