[Duane Bledsoe]

I’ve read that my DW618 router will spin a 2-1/2” raised panel bit if taken slowly and the wood not pushed fast through the cut. What’s the largest bit I could use and not have to consider it a compromise? I’ve been looking at some 1-1/2” bottom cleaning and bowl bits for freehand use and with potential built jigs.

 

[DesertRatTom]

I wouldn't consider using a 2.5 inch bit freehand, far too much danger of it flying loose and heading at high speed to a major artery. Big bits are for table use.

The power of the router makes some difference, of course, but it helps to cut several times, taking off a little more each pass. I limit myself to about 1/8th per pass by leaving the height pre set, and moving the fence back a little after each pass.

 

[Duane Bledsoe]

Sorry, I wasn’t very clear on what I meant. That’s what I get for rushing my post while trying to leave the house. What I meant was I know the 2-1/2” bit can be used in my router and in a table, but it seems like a compromise because I can’t just put it in and use it without giving it another thought like I can a 1/2” roundover. That got me to wondering what’s the largest bit I could use and not really have to worry that the router isn’t strong enough to spin it well? I’m wanting to pick up a bit that I can use for a planing jig. I want to make a jig that allows me to pass a board through and run my router over it to thin it down. I was looking at a bowl carving bit or a bottom cleaning bit and I found them in various sizes in 1/4” increments. I figured 1-1/2” would be large enough to be servicable while not being too stressful on the router.

Also the bowl carving bit seems less likely to leave lines than the bottom cleaning bit would. Any thoughts on this?

 

[Duane Bledsoe]

Was just recalling, I have a rabetting bit that would be along the lines of this in terms of size and weight. If it works then a bowl carving bit would also work. So I guess I just need to get one and start building a jig.

 

[Cherryville Chuck]

It's not necessarily how big a bit as much as it is how deep a cut and how fast a feed speed Duane. You can compensate for the lower horsepower. I've run 1.5" bits in a 3+ hp router for leveling and I don't recall even having to go that slow but I was probably only taking off a 1/16th.

 

[Duane Bledsoe]

That’s what I want to do, but I only have a 2-1/4 HP router. It would be really great if I could run up to 2” bits. Do you think a DeWalt DW618 would handle a bit that large while shaving off a 1/16” of wood, ran on the slowest speed setting the router has?

 

[Stick486]

in all of this is the information for you to make up your own mind...

.

 

[sreilly]

Duane it's best to go over the information Stick is referring to and understand it before attempting anything like this. I have a 2-1/4HP Bosch and it can do raised panel cuts just fine but the speed needs to be adjusted for the bit size and the face amount/depth needs to be appropriate for the router by making repeated cuts. Look for a speed chart for your router that explains the speeds vs bit diameter. But certainly look at the above info Stick refers to. It would be a mistake not to.

 

[harrysin]

This 1 1/4" dish cutter, second shot, has had regular use in hand-held router and as has been said, there is little chance of lines between cuts compared to a bottom cleaning bit which must be set absolutely square to the work-piece.

 

[DesertRatTom]

If the material isn't flat, bowedor twisted, you'll need to prop it up in order to flatten it uniformly across the full width. You will also want to have a jig to guide the 618 router as it flattens the top. If you have a good #4 or #5 hand plane, you could shave down the high spots on the inside of any bowing to help level it so it is stable on the work surface. Stick's pictures show the router running on a pair of bars.

The two pictures show variations on simple router sleds. Note that the outside long edges have an added piece on each side to restrain and guide the router as you move it across. Once the workpiece is planed or propped up, you adjust the depth of cut by raising or lowering the bit. Go lightly in small steps until a straight edge show's it is flat on one side. If you have a planer, you can level the other side, or flip it over and use the router to cut the otherside til it's flat. You will still need to do a little sanding and scraping to have a finished surface. You'll need to buy stock somewhat thicker that your desired finished thickness.

Harry's Router Sled jig uses metal bars to keep the bit cutting level all the way across, the pictured designs use some very flat Baltic Birch ply for the guide's runners. The smaller edge guides reinforce the jig and keep it flat. The opening needs to be a little wider than the biggest bit you plan to use. The opening doesn't need to be adjustable since the outside guides need to be a close fit to the router base.

Notice that the picture with the slab shows use of wedges to level off and keep the slab from rocking.

It is flattening the second side that renders the piece parallel and usable. Note that in the second picture, the maker used aluminum "L" bars.

 

[Gene Howe]

I just finished a flattening job on a slab of mesquite. Used a cheap 2" bit @ 1250 rpm in a Freud 2000 rated at 3.25 hp. Judicious use of wedges insured level cuts. Even so, I don't think I ever went deeper than a 32nd of an inch. The slab is live edged but, approximately 18" X 24". Took about an hour and a half per side.
Thought about using the bowl bit, but it is only 1 1/2" wide.
If the stock has one good flat face and is small enough, a planer would be my first choice.

 

[TwoSkies57]

With the popularity of slab lumber in recent yrs the market has been taking advantage of the trend with DIYers. I got slab lumber around here like it was 2x4's.. or so it seems. Anybody with a dead tree in the back yard is having it milled into slabs and asking crazy prices....oh well,,, gonna be lots of great deals to be had in a couple years.
Unless they hear of "air dried" lumber..Yikes...

any hooooooooo... I've seen planer bits up to 3"'s in diameter..the bit itself looked kinda iffy at best. wouldn't touch it with a 6 HP router. Personally, 2"s is about the max I'd go to or be comfortable with. And the more mass the better. Infinity has a new one that fits that bill nicely at around 100.00 with a 2' cutter. Amana has a 1 1/2" carbide bit with replaceable cutters for *GULP.*.....in the 180 neighborhood. Not my neighborhood, thats for sure...*L* Whiteside has a really nice spoil board bit for around 70 bucks. (not sure if it qualifies as a cross over or not??)

Not a big fan of bowl bits only cuz by the time you take into account the radius and overlap you're probably cutting well less than 1" worth of material with a 1 1/4" bowl bit. In the end, the set up and the jig used are every bit as critical to success as the bit being used. IMHO...A 2 1/2 hp router should be plenty big enough,,, just let the router tell you how fast and how much you can get away with.

just my 2 cents worth...

 

[harrysin]

As nice as your jigs are, the ski mounted router is far more versatile..

 

[Gene Howe]

Harry, I totally agree. Just gotta get in gear and build one.