Thread: Help with routing Square dog holes using a template

Don't really know a lot about spiral bits myself; never felt the need myself.

I can tell you that what you're doing is awfully hard on a 1/4" shank cutter of any sort.

I'd recommend only 1/2" shanks for heavy duty or deep work, including your template following. Maybe a 1/2" shank 1/2" top bearing flush trimmer with a slight up or down shear. In other words not actually a helical spiral, but just a slightly less or more than 90 degree slope to the cutting edges, ditch the guide on the second router and just trust the top mount bearing to keep it on the straight & narrow path for your finishing "climb-cuts" against the template.

As already mentioned, a sacrificial backboard will eliminate almost all spelch when trenching across grain.

Thanks for your input.
The first bit clearing out the waste is 1/2 inch bit with a 1/2 inch shank. The template bit sounds like I need to beef up to the 1/2 inch shank variety.

This article from shop notes shows the operator taking light bites to clear the waste and then full depth passes with the template bit. Can somebody confirm that the template bit drawing is correct in that at less than full depth the bit won't cut the template. I guess this would work if the bearing was slightly larger than the cutter ?

Paul, a less than full depth pattern bit will be fine. The bearing rides on the template for the first pass then on the routed surface for the second pass. I'll check my router bits and see if I have something that would suit. I know I have a couple of pattern bits but I can't remember what size shank they are.
I see what you mean about the drawing. Yes you would damage the template if you hit it. A much better idea is to use the template guide in the router with a spiral bit for hogging out the bulk of the waste.

I just checked and I have a CMT 1/2" shank, 3/4" dia, 1" depth of cut pattern bit. I can drop it in the post if you want to try it.

Thanks for the offer. I'll keep it in mind.

Originally Posted by NCArcher

I can drop it in the post if you want to try it.

Are you kidding? Didn't you see what he did to that other bit?

As a suggestion, why not use a template with a calibrated oversize on the dog hole opening, and normal template guides. Use a 1/2in shank bit and two template guides of different sizes, one set to compensate for the oversize opening in the template, and the other 1/8th larger.

Use the larger guide to hog out, because it is larger, it will hog out a smaller area leaving 1/16in left along the dog hole sides. Swap to the smaller guide and finish to final size allowing for climb cuts where the bit would otherwise cause breakout, and normal cuts at the other end.

No need for pattern bits etc, single router bit for the job, and a 30 sec or so change of template guide to transition from hogging to trimming. Bit can't gouge the template as long as the template guides are inside the template opening while you plunge or raise the bit if the router base is resting on the template.

With spiral bits, there are two basic types, upcut and downcut, and one special, a compression bit, which is a combination of both, in a single bit. An upcut bit has a spiral in a similar direction to a normal drill bit, and is intended to draw the chips out of the cut, at the expense of potentially causing breakout at the surface the template or router base rides on. A downcut bit has a reverse spiral and minimises surface breakout at the expense of trying to retain the chips in the cut rather than ejecting them. The compression bit is a special case with an upcut at the tip transitioning to a downcut at the shank. This is used for cutting sheetgoods and is arranged so that the shear angles mean that at each surface the shear angle is directed towards the core of the board which backs up the cut and minimises breakout on each surface.

Thanks Malb. I thought I would make two templates just in case so it's definitely a method to try.
I am assuming that there may be potential for some slight variance in width when swapping templates even if I was careful.
The bit I have is a spiral up cut.

I have isolated all but 1 of the problems now with the triton router. The remaining issue is that I am having some problems with the plunge lock when using the router in the hand held mode. I have locked out the round plunge mechanism using the plunge selector lock. I am using the plunge selector lever. However I am not getting a good result. To the point where when I am in the middle of a cut the router will move up or down as the plunge lock releases on its own. This happens more so when I am doing a climb cut and the brass screw that is locked by the plunge selector seems to vibrate loose. I have removed the brass screw and the end is flat. Should I be using the lever or am I better off using the geared plunge selector?

Originally Posted by Pac man

... I am in the middle of a cut the router will move up or down as the plunge lock releases on its own. This happens more so when I am doing a climb cut and the brass screw that is locked by the plunge selector seems to vibrate loose. I have removed the brass screw and the end is flat. Should I be using the lever or am I better off using the geared plunge selector?

The plunge lock lever has an hexagonal head onto which the thumb lever fits and is held there by a screw. The position of the thumb lever is, therefore, adjustable relative to the screw shaft itself. Perhaps the lever needs adjusting counter-clockwise so that you can exert a more positive pressure towards the end of the lever throw - that would be my first port of call regarding the plunge lock vibrating loose ( see the exploded parts diagram to be found at http://www.raygirling.com/tra001.pdf - items 71 - 75).

I use the rack-and-pinion mechanism to reach the plunge depth, more often than not. Once I do reach it (as determined by the use of the plunge depth stop), I then lock it with the thumb lever, thereby giving a very stable retention of the set depth.

HTH

Ray

Originally Posted by rayintheuk

I use the rack-and-pinion mechanism to reach the plunge depth, more often than not. Once I do reach it (as determined by the use of the plunge depth stop), I then lock it with the thumb lever, thereby giving a very stable retention of the set depth.

HTH

Ray

I don't have a Triton but I lock my Makita a similar way. I screw down the depth adjustment till it hits the stop then lock it in place with the thumb lever. (Although I cant remember the last time I took it out of the UniLift )

Thanks Ray and Tony. Looks like it's belt and braces when I try this tomorrow.

Also read Rays post that Tony linked to in Flettys "ouch" thread and discovered that the collet issues I experienced are because I have the older TRA001 collet design. Ray does it affect the 1/2 inch bits or more the 1/4 inch or its both?

I also gave gave the end of the brass a sand to make it a bit grippy so hopefully that helps.

Originally Posted by Pac man

... I have the older TRA001 collet design. Ray does it affect the 1/2 inch bits or more the 1/4 inch or its both?

The older (known as "Hitachi-style") collet suffers from very shallow shoulders and a very coarse thread. Effectively, this means that the high 'gearing' of the nut thread requires many times the effort to tighten than if the thread were finer and the shoulders sloped more. Adding a reducing sleeve only compounds the problem. The newer (known as a "self-releasing") collet has just those features and as well as being easier to tighten properly, it is also easier to release, although the action required seems strange at first.

When removing a cutter from the newer collets, release the nut until it feels slack, then give it an extra turn to release the bit. It doesn't feel right at first, but whatever you do, don't try to pull a cutter out of the newer collet until you've undone it for the second time, or you will shred your fingers!

The main additional benefit, in my view, is that you can then have dedicated ½" and ¼" collets, removing altogether the need to use a (sometimes dangerous) reducing sleeve.

Ray

Well tomorrow never came...
however today I was able to finish this off.
i think that I have had enough template routing for a while.
4 templates, 2 template bits and a new router and its done.Thanks to those that helped

My router base has one straight edge built in (not external fence). You can easily make straight edge base from 1/4" thick plastic or wood. Just be sure to center it perfect.