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I have a 1.25hp Craftsmen fixed base router and table. Is there a way to build a plunge base for a fixed base?
Or another method to "plunge" into a surface with this equipment?

If you have access to a machinist's shop, you might be able to pull it off. However, the tight tolerances demanded to have a router plunge without having any travel or error are probably unatainable if you don't have the proper tools. It's probably better just to bite the bullet and buy one if you really need it.

That being said, I have an older Black and Decker Professional series router that has a depth of cut adjustment that is set on a micro knob. If I loosen the wing-nut that holds everything just so, I can use it as a plunge base, if you will. Works great for me and there's no travel since I just slacken everything just enough to get the router moving without inducing rocking with the base.

What is it that you're plunging into, exactly (question mark)

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I'm sure it is. But i'm not that smart enough to think of a way. I know there are plunge base out there that can be purchased for removable motor type routers.

A router table is designed for through cuts, side and perimeter cuts, and light shaping. It's not really designed for plunging. If there's a specific closed route application you need to cut, you're better off using a plunge router and a template rather than trying to rig up a router table for something it's not meant to do. And attempting to jury-rig a high powered, high speed cutter, is not recommended. There are bases made for plunging, and though they may be expensive it's worth waiting until you can get your hands on the right tool for the job.

And sorry to digress, but Alain - the signature, is it really necessary? I certainly appreciate the irony however, in that the quote is so often used in ignorance of it's author, the Marxist, socialist playwright and philosopher George Bernard Shaw. Something tells me the author's intentions may be misconstrued when taken out of original context.

My apologies for the sideshow folks, but I was a bit irked. I'm through now.

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Eschew obfuscation, espouse elucidation.

Unfortunately, the model router that I have there was not a plunge base sold for it. I'm currently designing a spring loaded "plunge" base for my fixed base router with the sub base removed.

Here's my corollary : "Every time you take from Peter to give to Paul, you end up with a sore Peter!"

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JJ
Napa, CA
http://www.DonohueGuitars.com

David, I’m sorry if my signature line has caused you angst or a rise in your blood pressure. It was certainly not my intention to rattle any cages, as it were.

Indeed, I’m very much aware that this is a GBS quote. Unlike North Carolina representative, Virginia Foxx (R), whom, while addressing the legislative assembly and haranguing President Obama’s economical stimulus plan, wrongfully attributed this pearl of wisdom to Samuel Clemens, I am a Shaw fan and I have read many of his works.

The quotation in question appeared in Everybody’s Political What’s What (1944). It tickled my fancy and for me, it had no bearing on today’s dire economic straights or all the kerfuffle surrounding it, was not intended in any context, nor was it proposed as a criticism on the present Administration. However, I can see that it does have a political connotation, and for that reason, I have decided to remove it lest I incur the ill will of the more astute and politically sensitive amongst the board.

To answer your question, no, it certainly was not necessary. Do I believe it is advisable to steal from the rich to give to the poor? I’m sure it is not for me to pass judgement on matters that far eclipse my understanding and this forum certainly wouldn’t be the pulpit from which to proselytize.

Again, I’m sorry for disturbing you and I remain, sir, with assurances of the most profound respect, yours very truly.

Alain

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

OH, so true, now a days we should really protect all of are rights

You're way ahead of me there Alain. I made it through half of one of his books about 15 years ago, and that's about it. You just caught me in a particularly pissy mood when I saw the quote in your signature, and didn't feel much inclined to practice restraint (it's great stress relief be an ass every now and again). Politically, I've got a pretty itchy trigger finger, and that line just seemed to run very close to the vien of some current tensions. No harm, no foul, all's well.

DG, welcome to the forum. Politics are off limits here of course, but once in a while things come up. So long as it's between friends who have known each other here for a while it'll generally blow over fairly quickly, and all will be calm again, or relatively at least. If it gets particularly bad, sometimes discussions have to be closed, and a private thumb wrestling match arranged to settle things up. Just as a caution to a newer member, tread lightly when you see things like this. Some folks around here have some pretty tough thumbs.

As to your plunge base, that can be a tricky thing to make work well. You really need a pretty tight, solid, and precise vertical travel, without which you can end up making some pretty ugly cuts. Good luck with it, and above all, keep safety as your first concern when making or modifying tools like this.

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Eschew obfuscation, espouse elucidation.

Well, I made the opposite of a plunge "router" (if a Dremel can be considered a mini-router.)

This design keeps the bit into the plunged position until the bit is retracted.

With the spring functionality reversed, this could be made into a plunge router. The key is 2 pieces of nesting/telescoping brass tubing (a cheap linear bearing) of different lengths, one piece epoxied into the wood. The (flathead) bolt that comes up through the base snugly fits inside the inner brass tube (I even put some epoxy on most of the threads, to make it fit without slop.) Atop the upper springs are washers (spring stops) and an acorn nut. Works pretty slick.



Another possibility I've thought of would be to put a thumb lever on this, to retract the bit, or to ease down (plunge) the bit into the work. For a larger router or even a laminate trimmer, you'd probably need to use larger bolt and tubes, or perhaps just use 4 rather than 2.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Hey guys!
David, thanks for the advise, I'm definitely not very political, although I think I would make a great polititian. It's all show biz. LOL

Dennis, That is an awesome design, Its pretty much exactly what I was thinking. Acouple of question though, On plunge base routers, is there a lock to set your depth after you have "plunged" the surface. Also once I have plunged the surface(however possible)could I just use my fixed base at a shallow depth to continue the routing? Like if i drilled a shallow 3/8" hole then used a 1/4" straight bit, starting in the drilled hole to start the routing.
Thank you guys for all your help!
Daniel

Hi Daniel,

Sorry, I didn't see your reply.

Hmmm... Plunge routers generally do not have a "lock", so that you can retract the still spinning bit whenever you want by releasing your downward hand pressure. But I'm not sure that was your question, and you may be wondering about setting a depth stop. Plunge routers usually (always?) have some sort a sort of "stop" that allows you to pre-set the desired maximum depth of the plunge, and a spring (or springs) to allow you to relax the downward pressure brings the bit back up.

The reason that I made my rosette cutter a "reverse plunge router" (still don't know what to call it), is so I would not have to fuss with downward pressure to make the cut, and I could then concentrate on holding the jig lower with both hands, to get more control over the bit as it advances through cuts that are against the grain as well as with the grain. So, in effect, I do "lock" my router in the plunged position (well, it is held down by springs), and I only need to worry about retracting the bit. The depth stops for the unit I made are the nuts just below the plunge platform (curly Maple.) To keep the stop nuts from moving on their own, I could have used nylon lined (Nylock) nuts there, or a pair of nuts ("jam nuts"), but for reasons I can't remember, I used springs which does keep the nuts from turning on their own.

One of the big issues that is solved by a plunge router is to eliminate the kick associated with the overall tool on startup. ("Soft start" have less of a kick, but there will always be a little.) You can also neatly stop routing whenever you want without fumbling for a switch, and eliminate the bit wiggling in the work at shutdown, by retracting the bit from the work before shutdown.

Yes, if the area to be removed is large enough, you could do that. Careful on startup that you do not make contact with the side of your drilled hole before you are ready, as that may cause a drastic, out-of-control cut. A foot switch would help with that, and maybe full safety goggles rather than glasses so you can get your eyes close to the work. I have also used a router with a standard base to make a "tilt plunge", where you contact one edge of the base, turn on the router, and tilt it into the work. Obviously, you need to have some leeway to do that successfully, as you'll rarely ever get clean entrance and exit of the bit (unless you trap a square router base between wood stops or a template. If you are going to use a standard base and tilt plunge, cut, then try to lift straight up or tilt out the still spinning bit, I'd recommend you practice on scrap of somewhat the same density before trying your good wood.

HTH,

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia