[jamesyawn]

Perhaps overly bold of me to start a new topic on my first post... feel free to chastise me if this is the wrong thing to do...

But I'm looking for a table-saw blade that will cut a kerf 1/4th inch wide with a ROUND bottom. That's so a 1/4th inch dowel will fit in snugly and evenly, with a little Titebond and rubber-mallet persuasion.

So far, I've used:
Dado blade (round peg in square hole. Inelegant.)
Three circular blades together (slightly nicer square hole.)
Forstner bit applied tangentially (good result but labor intensive.)
Router table (tricky and labor intensive.)

The table saw is quick and easy for this application, and would be perfect if it would just cut a round-bottomed kerf. Numerous web searches have turned up no blades for this purpose.

I could have a machinist make me a custom blade, but wonder if there is something already available on the market.

Suggestions? Ideas? Rude remarks? I'm open!

Jimmy Yawn

 

[Steve Neul]

You might use a router on a router table which may get better results. You could just use a 1/4" bull nose router bits that would do it unless the dowel is swollen from exposure to humidity. To do that on a table saw you might have to get a molding cutter and grind a custom blade to fit your needs.

 

[Burb]

I'd suggest using a Core Box Router Bit, like this

http://www.grizzly.com/products/1-4-R-Core-Box-Bit/C1231

Mark

 

[mdntrdr]

Yep, 1/4" Core Box. :smile:

 

[woodnthings]

Crfatsman molding head

This one has a bunch of different cutters . Just grind the most likely one into a 1/4" diameter end.

http://www.ebay.com/itm/Craftsman-9...559?pt=LH_DefaultDomain_0&hash=item3387b45d0f

 

[cabinetman]

Perhaps overly bold of me to start a new topic on my first post... feel free to chastise me if this is the wrong thing to do...

Not really the wrong thing to do, but we have an introduction section where you can say a few words about yourself. If you fill out your profile in your "User Control Panel", you can list any hobbies or other facts. You can also list your general geographical location which would be a help in answering some questions.

I also vote for the core box router bit. That would be the best method IMO. Saw blades don't have the width in their tooth design for ¼" wide profiles. It would likely be very costly to have one made.

Using one of the moulding knives for a table saw moulding head and reshaping it to make the groove would be difficult with DIY home type tooling.

.

 

[knotscott]

Welcome James. I don't know of any saw blades that exist that will give you a rounded 1/4" profile. A molding head cutter may have a profile that will do it, but I'd think the core box router bit that others have suggested would be the path of least resistance.

 

[4DThinker]

Split the job. Cut 1/8" deep slot with the table saw, 1/4" wide. Use the core-box router bit set 1/4" deep to run down the same slot. Easiest on a router table with fence, but can be done with a hand-held router and a straight-edge guide.

 

[FrankC]

Not sure of application, can you just glue 1/2 round molding to surface of board:
http://www.superior-dollhouse-miniatures.com/miscellaneous-building-materials/30737-half-round.html

If you are burying it then use a router in a table and an appropriate bit as suggested.

 

[woodnthings]

This will work

Just bush it from 3/4" to 5/8' for the table saw. Use or make a wider throat opening for the insert in the saw.
It may not be a large enough diameter at 2 /5/8" but the depth of cut is unknown....

C2046 Shaper Cutter - 1/4" Flute, 3/4" Bore

http://www.grizzly.com/products/Shaper-Cutter-1-4-Flute-3-4-Bore/C2046

Your Price:**$25.95

In Stock​

(Click for showroom pickup)

 

[jamesyawn]

1/4th inch round-bottomed kerf

Thanks for the excellent suggestions. I'll get one of those bull-nosed bits next trip to Home Deep Hole.

I've done the two-pass thing with the table saw then Forstner bit, but it's a pain to get the work aligned perfectly 62 times for rack (cookie/cake/bread-cooling racks.) It took 90 seconds on the table saw to make nicely-spaced square kerfs, 90 minutes at the drill press to make them round. The router bit should be much quicker.

The molding blade looks like what I originally had in mind, and would do it all in one pass. I might impose upon my machinist buddy to make me custom tips, or re-shape an existing tip.

Thanks again!
Jimmy Yawn
[email protected]

 

[jamesyawn]

C2046 shaper cutter

Apologies, I did not see this item before making my last post. (Darned modem connection... pictures load sloooow.)

It would be perfect... if my table saw would raise up that high. Just measured, and the spindle (center) only comes up to within 1.425 inches of the bed. This particular blade would only reach up 1.3125 inches, below the bed of the saw.

So do I need a better table saw? Perhaps better question is...what type of machine is this sort of blade used in? Maybe that's what I need.

Jimmy

 

[Alchymist]

Apologies, I did not see this item before making my last post. (Darned modem connection... pictures load sloooow.)

It would be perfect... if my table saw would raise up that high. Just measured, and the spindle (center) only comes up to within 1.425 inches of the bed. This particular blade would only reach up 1.3125 inches, below the bed of the saw.

So do I need a better table saw? Perhaps better question is...what type of machine is this sort of blade used in? Maybe that's what I need.

Jimmy

Shaper -
http://www.grizzly.com/products/3-4-HP-Shaper/G0510Z

And yes, that would do the job....

 

[woodnthings]

Yes, it is a shaper cutter

Shaper -
http://www.grizzly.com/products/3-4-HP-Shaper/G0510Z

And yes, that would do the job....

BUT, shapers only work on the edges of panels/boards.
To make the rounded bottom kerfs in the middle of a board on the face or in the middle of a panel, a shaper won't work. :no:
So, we are back to square one.

It's possible you could use a circular saw which will get you more blade out of the base, but that would be an "experiment"considering the bushing and thickness of the cutter and all.

The thing I like about the shaper cutter is the large amount of gullet which allows for easy chip removal and it will be turning a lot slower, less chance of a burn out. But I'm afraid the dang thing is just too small around to work in the table saw. HMMM I wonder about a RAS. which has very little "machinery" below the base of the motor's shaft/arbor.

What's the required depth of the cove? Sounds like about 1/4"...
Maybe it could work, but then you are limited by the cross cut capacity of the RAS. usually about 15" or so.

 

[cabinetman]

With a shaper, the bit cuts horizontally. Depending on the specific machine, how high the bit can be raised would depend on how far off the table the groove could be placed. For some items, the groove could be positioned higher than what would be considered the edge of the board.

.

 

[jschaben]

So far, I've used:
Dado blade (round peg in square hole. Inelegant.)
Three circular blades together (slightly nicer square hole.)
Forstner bit applied tangentially (good result but labor intensive.)
Router table (tricky and labor intensive.)

Jimmy Yawn

Hi Jimmy - I don't understand what kind of issues you had with this, router table would be my first choice unless the board was to large. :blink:

 

[rrich]

I've seen them at woodworking shows. They are similar to the molding head cutter.

Spendy! ($300) range. They are purple in color.

If you have an old dado blade set, you could get the outside blades sharpened to the 1/4" that you need.

 

[rrbrown]

Why all the overthinking guys?

Routerbit is the best and cheapest solution offered.

 

[GeorgeC]

Why all the overthinking guys?

Routerbit is the best and cheapest solution offered.

I am with you. A 1/4" cove bit should be all that is needed.

George

 

[woodnthings]

It's not overthinking

Why all the overthinking guys?

Routerbit is the best and cheapest solution offered.

I am with you. A 1/4" cove bit should be all that is needed.

George

Of course a router bit will work. It's about alternative methods. If I had 500 grooves to make, spaced 1/2" apart on pieces 3 ft long, I'd be looking at a different method. BUT we don't know what the application is.

If I could get that shaper cutter to fit my saw, I'd use it and for $26.00 it ain't all that exspensive, maybe less than what the router bit would cost, I donno? Try to find an 1/8" radius cove bit, I couldn't on Amazon or from Amana.... :no:
Because of the small radius it will probably heat up and dull pretty rapidly, depends on the quality and the length of the run.