I’m trying to hone down my research for a blade that with truly flat kerf to cut box corners for spines in thin walled material. I’ve looked at the Forrest WW10401125 (@ about $150) and the Holbren TS2000 (@ $119). Anyone have an opinion, or other suggestions for blades with high tooth count ?
Discussion Forum
Get It All!
UNLIMITED Membership is like taking a master class in woodworking for less than $10 a month.
Start Your Free TrialCategories
Discussion Forum
Digital Plans Library
Member exclusive! – Plans for everyone – from beginners to experts – right at your fingertips.
Highlights
-
Shape Your Skills
when you sign up for our emails
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. -
Shop Talk Live Podcast -
Our favorite articles and videos -
E-Learning Courses from Fine Woodworking
-
-
Replies
Use a dado blade cutter?
“[Deleted]”
The Freud Heavy Duty Rip blade has flat teeth. I use it for grooves all the time. Also great for thick hardwoods. https://www.freudtools.com/products/LM72M010
Ditto the blade mschlack linked.
I also use the Freud box cutter set. It has 2 8 inch flat bottom blades. Use 1 blade for a 1/8 groove, or 2 blades for 1/4 or 3/8, depending on which order they are on the arbor. It makes a truly flat bottom, no matter the width.
Re. Freud Box Cutter set. I just checked the spec on the SBOX8...I didnt see a 1/8" blade with it? Are you using an older model?
I also have the Freud Heavy Duty Rip as mschlack recommended, although it is not "high tooth count" as it has 24T, it seems to work fine for splines and its a dead flat/square cut and might well be the "standard"- I got it because Bob Van Dyke recommended this option for cutting flat bottomed grooves, spines, etc. (as well as for heavy ripping) in an article on table saw blades. I have Forrest box cutter blades, which are like much the Freud's John_C2 mentions - very handy to have, e.g. 8 inch blades, which also have 24 teeth and use them to cut rabbets and grooves. I haven't ever used these to cut splines although they would probably work ok.....even with a 3/4 inch sled base on the jig and only being an 8 inch blade, it would probably make cuts deep enough for splines.
My experience with a truly flat top tooth table saw blade is with the Forrest 10 inch. I have definite success using the Forrest product.
Without any actually trials, I'm skeptical of using a rip blade to cut corner kerfs in 1/4" box side material. Ditto for the idea of using a dado blade. I'll give the dado blade a try in the AM to see if my fears are founded.
I looked at the Freud Box Cutter set, but I'm now thinking about just having an older blade recut with flat teeth.
In any case: THANKS for all the input.
Just to get a clear understanding.....
Are you talking about making box sides with mitred corners into which you want to cut a thin groove to insert a matching spline for strengthening the mitred corners?
If so, most table saw blades are going to be too wide. But ...
If it would go into your saw and stick up enough above the table top, you could use one of the small (typically around 6" diameter) saw blades made for small hand-held circular saws. I have a Makita that takes blades with a 6 & 1/4" diameter that have a kerf of only 1/16". They come as both rip and cross-cut blades.
At that width, does it matter if the saw teeth make a dead flat bottom? Probably not, as any spline used is likely to be lifted only a teeny amount by a slightly-peaked saw-cut bottom; and that peak will probably compress to flat if you push on the spline a bit.
********
An alternative might be to use a fine-tooth tenon or dovetail handsaw to make such a kerf. All you need is a steady hand and a good eye. :-)
Another alternative is to do without splines and instead glue the mitred corners via a pre-sizing with watered-down glue before gluing up with the thicker stuff. Such mitre joints are quite strong just from the glue.
********
Yet another alternative is to use cross-corner splines, which are more visible but provide a decorative addition to box corners. I just made myself a fancy jig to cut those with table saw or router table.
Lataxe
Seriously!!!
If any decent rip blade doesnt cut a flat bottom kerf something's wrong in the universe. Many companies make dedicated box joint sets. Buy one!
Not sure how you think woodworking is different in your plane of existence but box joints are fairly crude anyway and asking for advice means you havent really tried enough. Dedicated factory machines historically cut them enmasse, quick and rough. Repeat - rough.
Too much analysis and hesitation. Must be some kind of engineer. Stop thinking about little minutiae. Get busy, suck it up, stop asking the basic repeat questions, and just try it.
Seriously? He did not ask about box joints.
I wouldn't think the dado blade will give the results I think you are looking for, my dado doesn't cut dead flat....I know the rip blade will work very nicely for splines (or keys) on the outside corners or inside splines on 1/2 inch or so stock. When you said splines in thin-walled, I guess I wasn't thinking as thin as 1/4 inch....haven't tried on a box corner that thin. Let us know what you end up with.
Sorry all....I'm obviously still trying to find the right balance between brevity and detail in an initial post. I wasn't trying to be either obtuse or overly fussy.
Yes Lataxe, the question about a flat cut came out of wanting to cut kerfs for decorative contrasting spines in corner miters of boxes with wall thickness down to perhaps a 1/4". (Thanks for the detailed suggestions.)
While I spent 50 years as a jeweler (not an engineer) I don't think my arm and eye is steady enough to cut them to my satisfaction by hand.
Only loosely related: I have cut a number of box joints; they came out quite nicely, thank you.
If I'm understanding, you want to cut splines across a miter joint after its been assembled, correct?
A jig that also functions as a zero clearance is one option. Another is leave the sides thicker, allowing you to plane off, removing (hopefully) any tear out. Also a scribe mark helps.
Another option might be spiral router bit?
I use this blade from Lee Valley
Safety Rip Blade
Item 15T9024, Safety Rip Blade, 10" x 24 tooth
It works well with no gap.
Yep, I had always planned to make and use a 45 jig to hold the boxes when I cut the decorative corner splines; that was no small part of the reason I was asking for input on blades. I didn't to go to the trouble of making the jig for a zero clearance cut with a blade I wasn't fairly sure would be the best for the job.
Yesterday I sent an older 10 x 40T ATB blade (3/32" kerf) out to a sharpening service. They'll re-cut it with flat teeth...$20. Seemed worth the try. They warned me about reduced blade life due to the reduction in tooth size, but all I have ever wanted to a blade to cut shallow flat kerfs in box corners. It may take up to 10 days for it do get back to me; will report the resulting cut.
I add my two cents.
There is no reason why a ripping blades has to have a flat cut, it is designed for through cuts after all. Dado and box-joint blades are designed to be used in pairs and have dedicated positions, left and right, not to be used individually.
You want a cross-cut blade with a flat tooth geometry. You might be better off looking at a combination blade with flat raker teeth like this.
https://www.freudtools.com/products/LU84M011
Just a suggestion
There's no such thing as a flat top crosscut blade.
Dado blades are different animal altogether.
CMT makes a really nice affordable flat kerf blade CMT Orange Chrome 10” Carbide Rip Saw Blade, 24 Teeth, Flat Top Grind (FTG)
The potential problem as I see it, is that you want the clean cross-cut with a flat bottom. Most of today's cross-cut blades use a high alternating top bevel tooth set to achieve a clean cut across the fibers. Ripping blades, while having a flat tooth or teeth can provide the flat bottom but don't always cut well in a cross-cut situation. For spline cuts in thin materials, you could use an 1/8" straight router bit.
Just another suggestion
Is it possible to take a good rip blade with a typical tooth profile (which leaves a valley in the middle of the kerf) to the people who sharpen the blades and ask them to grind down the "peak" teeth to the same height as the flat teeth?
Speaking from no experience whatsoever it seems like it should be even easier for them to do that than to sharpen different teeth for different profiles.
Are there any serious downsides to that? I'm not even sure why rip blades don't normally produce flat-bottomed cuts.
Mainly because the "bottom of the cut" does not exist for a rip. Rip blades are designed to give a "pretty smooth" finished surface with no tearout. The peaked teeth of the ATB act as scoring blades just ahead of the flat top stock removal teeth. At a premium you gan get a "glueline" blade that boasts an even better finished surface. I think the glueline blades are just slightly backbeveled down the carbide to reduce side-tooth contact, but please post the correction if I have that wrong.
My original question was in search of a blade to purchase that would give me a truly flat kerf for decorative splines on the mitered corners of small boxes. With all the ensuing input and some other research, I ended up sending an existing 40 ATB with 3/32" kerf blade out to a local sharpener to have all the teeth all ground flat.
Yesterday I made up a quick 'n dirty jig and cut a few "test" miters on two boxes; one with 1/2" sapele, the other with 1/4" redwood. Here are some photos. (The poplar spline is just slipped in for the photo).
I'm happy with the result. Blade "sharpening" cost $19.00, and result fits my needs nicely.
One again, thanks for all your comments and suggestions !
Sweet! A nice thread too... Not many stay on page 1 for 17 days!
Excellent.
Regardless of tooth count, adjust the blade height just enough to clear the top edge of the board.
Mikaol
Have had good luck with Ridge Carbide, doing exactly what you describe.
10" x 40T STR +15 Hk 094 / .125" TS2000 Flat Top Box Joint blade
$139, and I used a 10% coupon I found on YouT...
Years ago, when I had some blades sharpened, the fellow had several used blades for sale that he offered to sharpen.
I picked out a 60 tooth Freud and asked that he grind the the tops flat. He said all rip blades are flat topped but not necessarily truly flat.
He did what I asked and this blade cuts some really nice box joints on 1/4" material - best part is it only cost about $15.
This forum post is now archived. Commenting has been disabled