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I need to purchase some 1/4" shank spiral down-cut bits and I can't seem to find them.......

1) So my questions are where do you get yours?

2) For routing rosette channels is a down-cut bit better than an up-cut bit?

3) I have used the 1/8" bits from Stew-Mac and have yet to wear one out. Stew-Mac offers a 1/4" collet for use with Laminate trimmers which is what I will be moving to for rosettes. Does the use of the collet increase the potential for runout and would I be better with 1/4" shank bits?

Many thanks!

Hesh buddy, You can get them at lowes.They are made by Bosch and work great for me.They cut alot cleaner than a straight one does for sure.Especually at the top side of the cut.And it would be better than running a collet adapter.They were $17.98 and i picked up 3 .Two 1/8" and one 1/4" cut with a 1/4" shank. The 1/8 is also good for doing bridge channels as well.That's why i got two 1/8".I don't use the rosette one on any thing else.

It looks like the SPPRC from LMI is a downcut.

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https://soundcloud.com/jeffreylsuits/he ... -runnin-13

The accuracy of a collet depends on the collet and the chuck, so it's hard to say if you're gaining much or not using a solid-shank tool. A good collet system definitely has way less runout than most routers. (About half of the tools in the Fadal are in ER collets!)

I've found that the smaller the bit, the less chipout and tearout you'll get. If I'm cutting cosmetic areas like rosettes, I'll go with the smaller cutter and two passes every time. A really really sharp 1/8" upcut will give you a cleaner (real) cut than a normal downcut, even though there will be little fuzzies around the top edge of the cut. The 1/8" carbide mills for aluminum tend to be really sharp. The house brand ones from USA Carbide are super sharp (bright finish). 1/8" is sort of a weird transition point...below that there's little benefit to down-spiral bits VS adding RPM, but there is benefit to down-cutting 1/8" and bigger cutters.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Hey Hesh,

Have you checked Carbide.com?

Here are search results for all downcut spiral, solid carbide router bits, all manufacturers that Carbide.com handles: search results

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Try this link:

http://www.mlcswoodworking.com/shopsite ... solid.html

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Peter

That's a great find: a woodworking bit supplier who isn't ripping off their customers! The prices are quite fair IMO, and they're inline with the price of the same product (carbide end mill) from a mill supplier. Contrast that with the 200% markup Amana puts on a standard 1/2" carbide cutter when they call it a 'router bit'!

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

This company has decent prices as well www.eagleamerica.com

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John Ressler

i got mine at lowe's too.

To highjack some, is there any advantage to "climb cut" the outside and inside edges of the rosette, or is it impossible to climb cut since we're "plowing" through?

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Hesh,

I think the downcut spiral bit allows the wood surrounding the cut to support the little wood fiber victims as they're being sheared off, as opposed to upcut. Probably very noticeable if your bits start to get dull. I think the upcut bits could tend to pull fibers up with it.

Darrin

Thanks everyone I am good-to-go with a source now!

Darrin that makes sense to me too. What I do know is that the down-cut bits that I have used for several years now have always made super clean cuts that I have been happy with.

Andy good question - hopefully someone with an answer will weigh-in.

hey hesh, i know you said you are good to go, but i just wanted to second mlcs as a great supplier. they deliver anywhere for free and i have been happy with everything i have purchased from them.

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sweat the small stuff.

Thanks Heath my friend!

I wouldn't buy router bits from MLCS. I did it once and all the bits I received are second rate at most, and dull. You get what you pay for.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Hey Hesh, I went through a bit of this just last week. You should be able to find my thread not too far back. I was looking at getting some fine bits to cut narrow perfling channels for a rosette. I spoke to two suppliers who told me not to use the really fine 1/8" bits in my Porter Cable 7310 as the runout would be too large and the bit would break. I'm still not sure I would break it cutting soft pine at a shallow depth, but I decided to stick with 1/4" shank. I was able to find a two flute straight 1/16" cutter on a 1/4" shank at Amazon: http://www.amazon.com/gp/product/B00004T7B2. I don't think you will find a spiral down cut on a 1/4" shank smaller than 1/8". If you do, let me know.

I don't know what kind of laminate trimmer you have, but I was told by PreciseBits that they will have an actual 1/8" collet for the Bosch Colt by the end of the month. That would be very cool.

Ken

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http://www.casperguitar.com

The climb cut side of even a slot will be cleaner than the conventional side, so you should try to climb cut the two perimeters of the pocket.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Thanks Bob, that's kind of what I was thinking as I was going through it in my head.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I don't think that I agree with climb cutting a rosette channel but I certainly agree with climb cutting binding channels.

None of my rosette channels were ever done with climb cuts. I would think that when climb cutting a rosette channel one has to make some plunge cuts which in my mind are more risky than not climb cutting. The climb cuts would be made in a visible location too - again more risky IMHO.

My rosette channel cuts are always started at the top under where the fret board extension will be and this is where my adjustments to my router base are made too. A sharp bit, going slow, multiple passes taking off a little wood each time and I don't see the need for climb cuts with rosette channels.

Also after each cut I lift the base and vacuum the dust because if the base, during multiple passes, starts riding on dust the bottom of the channel will not be flat because the dust raises the bit height slightly.

I brought this up because I've seen a few rosettes lately that have tearout on the soundboard. My kit from stew mac had some tearout I didn't notice until the rosette was inlaid and I've seen a pics here on OLF with some tearout right where you'd expect it with a standard cut.

The plunge thing could be an issue though, you're right. My jasper jig is mounted to a plunge router so it's not an issue there, but my W-K jig will be on a trimmer so it will be an issue there. I'll have to ponder that a bit. I guess if the W-K jig is as accurate as they say, you could plunge with the knob one full turn from where you want to be (.050") and then sneak up on the line.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I think you're confusing climb cutting with 'cutting downhill' (as shown on Stew-Mac and recommended for cutting binding). A climb cut is just a cut where the feed is the same direction as cutter rotation, VS a conventional cut where feed is counter to cutter rotation. No extra plunges needed.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Hi Bob - I don't understand what you are saying so are you saying that all cuts start under the fret board extension? If so are you advocating a clockwise rotation of the router in the circle cutting base going all the way around, partially around?

I always start my cuts and make my adjustments under the fret board extension and rotate the router clockwise completing an entire circle. I also make my first pass shallow and not at the final edges that I want the inside or outside of the channel to be at.

Do you really think that for a rosette if using say a 1/8" sharp bit that it matters?

If I'm remembering my directions of rotation correctly, you could climb cut the outside of the ring by starting under the FB extension and rotating anti-clockwise and climb cut the inside of the ring by rotating clockwise.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Andy: Yes, those are the right directions for climb cuts.

Hesh: I'd say that a climb cut helps quite a bit on anything over 1/16". You can probably get by without it 9/10 of the time, but it's that once in awhile where it would have made the difference where you'll notice .

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

If you cut and inlay your rosette a little deeper than needed and then inlay your rosette while the top is thick you can then sand down to the inlaid rosette, obviating any tearout on the surrounding spruce you may encounter. Climb cut or conventional cut won't matter as you are sanding away the top anyway.

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Sylvan
http://www.wellsguitars.com