Breaking bits on baltic birch

[brian]

doing a project in 19mm Baltic Birch.
Started using a .25 two flute straight bit at 3IPS @ 15000rpm,that bit lasted 20 minutes.I noticed the bit showed signes of overheating.
Switched to a .25 up spiral same rpm but 2.5 IPS,that bit lasted 15 minutes.Rechuck another upspiral and slowed it down to 13000 rpm.and finished the toolpath.
I'd would use a larger bit but don't have the room.
Any suggestions on IPS & RPMs with 19mm Baltic Birch.
I just ordered some .25 compression & down spiral bits so I'd like them to last longer

[drodda]

You can't cut baltic in a single pass with a .25 bit for very long. I use a downspiral .25 and stepdown .25 each pass with a small offset. then I have the machine come bask and clean the edge in a single pass. I cut baltic all day at 1.67 IPS at 15000 to 19000 rpm.

[jhicks]

If one believes the "rule of thumb" on bit cut depth/pass = bit diameter, then one would take 3 passes at the optimum feed and speed. Increasing the depth will require adjusting either speed/feed/or both.
We cut 3/4" 13 ply all day with a 5mm straight 2 flute bit, 160 IPM, at .260/pass on a PRT. I assume an Alpha would push harder or run faster.

[butch]

Brian
I do some Baltic Birch - 1/4in and 1/2in. I use 1/4" Down spiral, 2flute bits from Centurion Tools. I run these at 2 in per second and 12,000 RPM. Haven't had any problems with overheating, and get fairly smooth finish.

Butch

[cmagro]

Brian,

By any chance did you get your bits from MCLS? I tried twice using their 1/4" downspiral bits and twice they broke within 20 minutes.

In any case run over to Lowes or something and pick up one there (or any other manufacturer). If it works fine using the same parameters you'll know it's a problem with the bit.

Christian

[wberminio]

Same here Butch.

Centurion Tools are the way to go.
Haven't had a broken bit since I started using them

Erminio

[brian]

Sorry I guess I should have elaborated,I am stepping down .25 per pass.
The 2 flute straight bit I got from Lee Valley.
The upspiral was a freud I know there not great bits,but I live in a small town with Ferry acess only so I don't have bit supplier at hand.I just ordered some bits from CMT and I hope they are an improvement.
Thanks Brian

[butch]

Brian
That is my step down also.
Here is the web and phone for centurion tools.
They are usually very quick in their response. I have tried several different bits, but have the best results from these folks. Besides, they are very nice to deal with.

http://www.centuriontools.com/
phone:540.967.5402

Butch

[drodda]

I use only Whiteside bits. They have always worked good for me and I find them at a very reasonable price from Alan at http://www.woodworkersworld.net

Got to watch out for them evangelical centurion guys. I am surpised Jack Jarvis has not posted here about them, He works on commision I think.

-D

[centurion]

First of all, who decided we are evangelical? Second of all, We do not pay anything to Jack Jarvis or anyone else who speaks highly of our cutters. We make all of our own cutters unlike some of the others out there. We take pride in what we make, and sell. We have been in business for 11 years, and have not had to pay anyone to say good things about us, This includes customers such as Thomasville furniture, Bassett, General Motors, Siemens, among a long list of others. No need to watch out for us, what we make, we stand behind, because we know what it is when it goes out the door.

Fred
Centurion Tools LLC

[myxpykalix]

If I had a nickel for everytime i recommended them i'd be sittin in tall cotton. I only recommend them because they make great tools and they are good guys to deal with. They don't pay me to recommend them (but i would gladly accept anything they want to throw my way...hint, hint).

Their tools speak for themselves and they are nice guys to deal with and in this day of "give me your money and get out the door" businesses, when you find businesses (like Shopbot) who are interested in keeping you happy you tend to want to be loyal to them.
But Dave I had bought some Whiteside profile bits for that waincoting i made some time ago and I do like their profile bits.

[wberminio]

I definitely agree with Jack.I called Centurion some time ago,without a CLUE about which bits to buy.
Fred took the time to explain the various bits and options.
I Still have one compression bit that I have used to cut over 100 sheets of 3/4"prefinished maple and cherry ply, including Perimeter cuts and blind dados ,it is still cutting very well.

Customer service is the name of the game for all of us in these times.
Fred, Thanks

And Keep it up!

Erminio

[bcondon]

Dave,
Thanks for the comment.

I mean what I am about to say very seriously:
Dave's comment had Fred reply in a very serious way and stating his commitment to his product..

Jack and Erminio (who I met at his Shopbot camp - and ordered the following week) strongly supported Fred and his company.

I am new to the automation side of woodworking and there is SO much to learn that posts like this help me cut through a lot of data by finding good products.

Time to go look at the http://www.centuriontools.com/ but I will also look at http://www.woodworkersworld.net .

I did just purchase Her-Saf v groove 90 degree bit, and a fine ballnose 1/16" tapered bit (for inlays) from MSC

[harryball]

I've referred people to Centurion Tools in the past as well. They are a quality company and they make quality bits. I have no problem referring anyone to them, I can't say that for every company with whom I've done business.

/RB

[wberminio]

Bob
It's good news about the your purchase.
Hope all is going well.
We are planning to have another camp this spring.Hope to see you again!

Erminio

[drodda]

Fred,

I was not calling you Evangelical, Just Jack as I am on a campaign to give him grief whenever possible and the opening came in this thread and I took it. If I had a nickel for every time Jack Pasted your name on this forum I would be a rich guy also. Yes he has your praise saved on his clipboard to paste at will.

While I have not tried any bits from Centurion, Fred posting in this thread might make me take a look at what they have to offer. I have to admit that it caught me off guard when coming back tonight to see what Jack wrote and finding your post here. Glad to see you browse the forum. I wish more manufacturers did.

What I can say is that I have used over 300 Whiteside 1/4" down spirals this year alone. I have never been one to use a bit till it starts showing it needs replaced. I like having super clean edges so I change my bit frequently. I have never had a need to look elsewhere for a new supplier.

I have never been a bargain shopper when it comes to things that spin at 19,000 RPM's in my shop.

-D

[myxpykalix]

dave,
It's kind of hard to put humor or sarcasm in print. I knew you were goofin, so i had to give it back to you..lol
With all this "free publicity" for centurion maybe i can go collect my nickels now...

Dave, in all seriousness, if you have bought over 300 new bits due to wear it would seem that those bits are dulling (to your standards) quicker.
I would challenge you to do a comparison using a centurion bit to a whiteside for the same length of time and see if the centurion bit doesn't outlast the whiteside.

[terryd]

Just remembered why I don't post here anymore

[hh_woodworking]

If you are looking for whiteside and onsrud and other brand check out this link great company and service. better prices. Want quantity call and ask for steve bellew he will help you out.http://www.ballewsaw.com
Ed

[gpari]

Going thru 300 bits might also indicate that one is doing a whole bunch load of work.

I'll chime in a little. I buy bits from Amana, Whiteside, Onsrud (very rarely, dealer network is a pain), Centurion, and even the dreaded Orange Box store favorites Frued. I have different needs from each bit, and each different material. I have found that there is no one "silver bullet" in terms of bits. Yes, Centurion bits are good, but for my last project, they sucked. The equivalent Amana bit lasted over 6400 holes, while the Centurion clogged, heated up and surrendered after less than 20 (that's right, Twenty) holes.

My point is, find what works for you, don't be afraid to try different bits, and by all means do your own experimenting. I have learned much more by DOing than reading.

Good Luck,

Gabe "No Loyalty Here" Pari

[drodda]

Good point Gabe, I was sent some bits from a company to try. They were supposed to be the latest greatest thing since sliced bread. I installed one and turned the machine on. When the bit started cutting everyone in the shop hit the floor. I have never heard such an awful sound before in my life. It was all I could do to crawl out from under the desk to hit the stop button.

I was anxiuosly awaiting the call from the sales rep for these bits. This taught me that not every bit out there are similar. I have found one that works for me, however I am also the type that has never done a chipload calculation in the three plus years of running my Bot. The wood finish and sound always tells me if I am in the ballpark. Find what works for you and your style of work. There are many companies out there that offer good bits.

[pfulghum]

Today I just cut 2 full sheets (4'x5') of 1/2" baltic birch...

CMT 2 flute DownCut (Always downcut on vacuum table).

1/4" dia..3/4" cut length ... 7/8" exposed from the collet.

1/2" pass at 13K RPM at 3"/s. Default ramps of .4.


My rules to cut by...


1) You want to support your bit in the collet as much as possible.
2) Make shavings not fine dust. Adjust RPM and/or speed until you cut SHAVINGS. This will help with heat build up. If the bit is too hot to touch after cutting, you need to adjust.
3) Keep the bit moving, make sure your toolpaths aren't being so precise that the bit is making very minute movements. I try at use .005 or even .01 tolerance following curves.
4) ALWAYS have a spare bit around (at least one, or have a woodworking friend that lives close)

-- Pat

[bcondon]

Can I ask for you to post your top bits that work really well for you and what material they worked well in?

It would be ok also to say that xxx bit did not perform well in this application. This allows us newbees to get a direction.

In my case, I plan on using black walnut and yellow birch for an inlay projects... I bought a 1/16 bit 7 degree bit to try. the inlay is pretty fine...

==

V bits for signs. I purchased from Her Saf with replaceable carbide 1.25 w/ 120 degree

==

also bought starter kit from Shopbit (onsrud bit set)

===

The intent is not to bash a manufacturer but to get data. Fred may learn that someone had an issue with one of his bits which he know does well but there an issue either with application or speed/feed.

thanks

[ron_varela]

I have gotten a lot of email asking me what router bits are the best and what do I think are the best to buy, well for one a router bit to me depends on the steel used to make it is the most important because this will tell you the life of the bit and second is the speed you use to cut material.
My rule to choosing a bit depends on what final depth I am cutting and not the material I am going to cut, If I am going to cut or engrave something I first think about the final depth, if I am going to cut only ½ inch into the material and I want to use a ¼ inch bit I cut it in 2 passes and only use a ¼ bit 3/4 inch in length.
If I am going to cut material 1 inch deep and use a ½ bit I cut it in 2 or 3 passes depending if my machine can handle the pressure and the bit length is only 1 ¼ inch. You will find that you will break more bits using the wrong length because the pressure that is applied to them, the bit can only cut as fast as it is allowed, you put too much pressure on it and it breaks, you cut to slow you burn the material and burn up the bit do to heat, cut too fast and you burn or break the bit. I have only broken 1 bit in the last 10 years using my shopbot because as an old woodworker and using hand held routers one learns what speed and pressure is needed to finish the job correctly. So my advice would to use the correct router bit length and do not cut more in one pass then the diameter of the bit per pass. If your bit is 3 inches in length and you are only going to cut ½ inch into material push the bit up into the router so you only have ¾ inch of the bit showing and you will have a better chance of not breaking bits.
As for what is the best bits to buy and from who depends on what you want to spend, I have tried many different company’s and found that only good steel is the way to go, I found that price depends on what the company’s markup is, in the last 10 years I could not find any difference in cutting from an $10 ball nose bit with good steel and the same bit from a brand name at $40.00 and not knowing if it is good steel. It like buying a TV, you want to buy a 19 inch screen and you have 20 models to choose form and 20 different prices, but in reality you are just paying for a brand name because all the components are most likely made from the same manufacture, this is the same with router bits, most router bits are made by machine and most are made with the same type of machine but with different types of steel.
I have tried router bits from pricecutter.com and from other brand names and found that the steel make all the difference, so in some cases cheaper price and better steel is the best bargain around.
Just my 2 cents worth.

[jamesgilliam]

Thinking back over the last seven years I remember one of the first projects I did was a cabinet for my daughter. After about ten feet the solid carbide bit I was using snapped at the collet, and my thought was this is going to be an expensive hobby. Then it hit me, what about end mills for steel? Being an old oil field machinist I just figured they had to be tougher because they cut steel and other metals. The next day I went to my local supplier and bought two of the least expensive ones they had. Now they are almost all that I use. Feed rate is slower for x and y in wood, but not being a production shop it does not matter me. I cut 1/2" baltic birch in a single pass all the time, and 3/4" in two passes with a 1/4" bit. Sometimes my machine time runs a little long cutting at 1" per second, but to me the important thing is the quality on the finished cut, not speed. I do very little sanding on the final parts, and when I start seeing any "fuzzies" as my wife calls them on the parts I change bits. Usual life of them is around 6 sheets of material.

[gabepari]

I've cut over 30 sheets of 1/2" and 3/4" Baltic Birch with the same 1/4" compression cutter from Centurion (not preaching, just stating the brand of the current cutter in the queue, although they have been better than my Amanas). The pointy end of the bit is a little worn and pulls "fuzzies" upon ramped entry, but once it's plunged and cutting it works just like the 3rd day after it was new.

I usually use a 3/8" compression for Baltic Birch, but when I need 1/4" for nesting I cut 3/4" BB at 5ips 13K rpm, .600 deep climb cut first pass then .010 into the spoiler in the conventional direction. 1/2" BB at 6ips 13K rpm, .400 deep climb cut first pass then .010 into the spoiler in the conventional direction.

These numbers have seemed to work for me. I'm sure I could fine tune them a little. But each panel is always different, each day is different and I'm too busy cutting


Gabe