Byrd Cutterhead for Minimax CU300 Smart

[Frank Martin]

I have a 2006 Minimax CU300 Smart. I like everything about this machine other than the jointer/planer cutterhead that is Tersa. I had a carbide insert segmented cutterhead on another machine before and liked it better. Main reason for my desire to upgrade is tearout free surface regardless of feed direction.

Has anyone here done this before? I am looking to hear first hand experience about the effort/time needed to switch out the cutterhead and the improvement in performance. Also, the cost for the head. Would you do it again?

[Gregory Stahl]

I have a PM 180 with a Byrd head in it and an SCMI S520 with a Tersa. My 20" jointer has a Tersa in it as well.

My Byrd will tear out similiar to Tersa. I prefer my Tersa, much more economical to own. Break one insert in the Byrd and it will take several out with it.

If my Tersa starts to tear out, flip or replace the blades at a fairly low cost.

I would stick with the Tersa. Get a widebelt to sand your stock to thickness the last .05" instead of using the planer.

Best,
Greg Stahl

[Mike Hollingsworth]

Frank

I switched mine out last week. $1250 + $500 install. Very Pleased with results so far.

[Erik Loza]

Frank, what didn't you care for about the Tersa head, if I can ask? Just curious.

Erik

[Frank Martin]

I have a PM 180 with a Byrd head in it and an SCMI S520 with a Tersa. My 20" jointer has a Tersa in it as well.

My Byrd will tear out similiar to Tersa. I prefer my Tersa, much more economical to own. Break one insert in the Byrd and it will take several out with it.

If my Tersa starts to tear out, flip or replace the blades at a fairly low cost.

I would stick with the Tersa. Get a widebelt to sand your stock to thickness the last .05" instead of using the planer.

Best,
Greg Stahl

Greg, interesting to hear you have tearout with the segmented cutterhead. Wide belt sander is not an option as I don't have the room. In fact, I had a very nice oscillating drum sander but sold it to make space.



Frank

I switched mine out last week. $1250 + $500 install. Very Pleased with results so far.

Mike, can you tell me more about what you like better about the Byrd cutter head and why did you change? Is the Byrd head installation something complex that you paid a professional to install?


Frank, what didn't you care for about the Tersa head, if I can ask? Just curious.

Erik

Erik, my main motivation is tearout free results. I am thinking perhaps it is time to switch the blades, but I only ran about 300 BF of walnut, sapele and maple through it so far, which I thought is not much to dull the blades, but perhaps it is...

[Erik Loza]

Frank, what alloy Tersa knives are you running that you are getting this tearout with? My own experience and feedback from owners echoes what Gregory is saying: You'll get a better finish with straight knives than with segmented but alloy selection is critical.

Erik

[Frank Martin]

Frank, what alloy Tersa knives are you running that you are getting this tearout with? My own experience and feedback from owners echoes what Gregory is saying: You'll get a better finish with straight knives than with segmented but alloy selection is critical.

Erik

Erik, I am running M2 Tersa knives. Is it normal to start getting tearout after ~300 BF of walnut, sapele and hard maple most of which was the former two?

When I had a carbide segmented cutterhead I ran many more BF with completely tearout free results. I had other problems with that machine and that is the reason I switched to Minimax combo. I know Tersa has been around for a very long time and I like it too compared to the standard cutterhead due to easy knife changes, but I am surprised to hear that it would give the same tearout free results as a segmented cutterhead with carbide inserts. My first jointer was a straight blade standard cutterhead, which did give me tearout in expected situations. However, the segmented head was completely tearout free almost regardless of grain direction.

[Erik Loza]

Frank, have you tried HSS knives? M42 (Cobalt) would not be my first choice for those species.

Erik

[Mel Fulks]

I just looked at several sites selling TERSA knives. Don't see any mention of M2...only "high speed" and some named steels and carbide. If they were M2 they would say M2. What you probably have are knives "same hardness as M2" but low grade rubbish. A most common and dishonest ploy. The chrome steel is not real good either. Get the M42. If the knives were sold to you as "high speed" demand to return them for full refund.

[Mel Fulks]

Just found another site pushing "18 percent HSS ", that is so goofy it's probably from honest ignorance. I guess they mean T1 which is 17 to 18 percent tungsten and a good true high speed steel.

[Mike Hollingsworth]

Mike, can you tell me more about what you like better about the Byrd cutter head and why did you change? Is the Byrd head installation something complex that you paid a professional to install?


frank

Biggest improvement is noise. Big issue for my neighbors.
I use a lot of figured lumber and find that tearout is better with the byrd. We found that the bearings were shot, maybe that was the issue.

[Frank Martin]

I was speaking from memory regarding the knive alloy. I am pretty sure it is M42 instead of M2, as I know I chose cobalt thinking it is the appropriate one. Looks like HSS is more appropriate. I will try that next. Is HSS the all around better option or is there something that lasts longer before tearout sets in?

[Erik Loza]

Frank, in my experience, HSS knives give the best finish quality on figured species but also, a lot of that has to do with the wood itself. For example, you could easily dull a fresh set of HSS knives by running dirty wood through the planer. Or, I have seen particular pieces of wood that a spiral head would rip out just as much as any straight-knife head.

IMO, the best thing about a Tersa head is that you have (unlike spirals) numerous knife options, specifically for the reason you are mentioning. Would you own just one table saw blade? One bandsaw blade? This is not meant as a criticism but I am always puzzled when owners just "keep the knives that it came with" in there for years, then wonder why cut quality deteriorates and why the head gets noisy. All it takes is a few dirty boards to dull down a set of fresh knives and then, of course the results are not great. For example, I would hang onto those dull knives and use them when you want to skim some dirty stock. The finish quality won't be great but they'll work fine for dimensioning. Then, just swap in a set of sharp knives for finish work. That's the advantage Tersa has over every other system: You can swap them all out moments, so why not take advantage of it? Just my 2-cents as always,

Erik

[Frank Martin]

frank

Biggest improvement is noise. Big issue for my neighbors.
I use a lot of figured lumber and find that tearout is better with the byrd. We found that the bearings were shot, maybe that was the issue.

Hi Mike,

Thankfully I don't have a problem with neighbors. I also run a cyclone dust collector so there is noise anyway.

Based on Erik's recommendation I will go ahead and try HSS. If I eventually decide to go with Byrd, I will reach out to you.

Hope you enjoys yours!

[Frank Martin]

Frank, in my experience, HSS knives give the best finish quality on figured species but also, a lot of that has to do with the wood itself. For example, you could easily dull a fresh set of HSS knives by running dirty wood through the planer. Or, I have seen particular pieces of wood that a spiral head would rip out just as much as any straight-knife head.

IMO, the best thing about a Tersa head is that you have (unlike spirals) numerous knife options, specifically for the reason you are mentioning. Would you own just one table saw blade? One bandsaw blade? This is not meant as a criticism but I am always puzzled when owners just "keep the knives that it came with" in there for years, then wonder why cut quality deteriorates and why the head gets noisy. All it takes is a few dirty boards to dull down a set of fresh knives and then, of course the results are not great. For example, I would hang onto those dull knives and use them when you want to skim some dirty stock. The finish quality won't be great but they'll work fine for dimensioning. Then, just swap in a set of sharp knives for finish work. That's the advantage Tersa has over every other system: You can swap them all out moments, so why not take advantage of it? Just my 2-cents as always,

Erik

Hi Erik,

I will go ahead and get some HSS knives. I hope I end up solving the tearout problem. I did get better results initially, so perhaps the problem is dull knives. Too soon may be but not a difficult problem to solve with easy change knives.

Thanks for the help.

[Erik Loza]

Sure thing, Frank. I think you will be surprised at the difference with a fresh set of HSS knives.

If you are not already aware of these guys, a great vendor for Tersa knives...

http://www.wmooreprofiles.com/c-1007-hss.aspx

...Looks like $17.25 per knife for your machine. Best of luck with it.

Erik

[Mel Fulks]

M-42 IS a genuine high speed steel. No high speed steel should be bought without more designation than "high speed". I have not used M42. M2 and T1 will both give a better surface than what is usually sold under just "high speed".

[mreza Salav]

in my experience HSS gives a better finish because it can take a sharper edge but it dulls faster too; carbide on the other hand stays sharp longer but doesn't give as sharp an edge as HSS.

[Frank Martin]

Sure thing, Frank. I think you will be surprised at the difference with a fresh set of HSS knives.

If you are not already aware of these guys, a great vendor for Tersa knives...

http://www.wmooreprofiles.com/c-1007-hss.aspx

...Looks like $17.25 per knife for your machine. Best of luck with it.

Erik

Hi Erik,

I got my Tersa knives from http://www.tersaknives.com/M42_c_13.html. The specific knives I have are called M42+. Here is what they say about these:
"




M42+


M42+Tersa™ Planer Knives are a HSS knife with a slightly different angle to the blade that makes the knives more durable and a perfect match for use on hardwood like maple or oak. "




So, looks like these knives are supposed to be more durable than the plain HSS, but perhaps with a compromise on finish quality.

[Erik Loza]

....So, looks like these knives are supposed to be more durable than the plain HSS, but perhaps with a compromise on finish quality.

I'm not any expert on metallurgy except to say that "yes", the Tersa knives labeled HSS have always had the best finish quality for me. But again, take care of your knives. My wife has a beautiful set of kitchen knives but if I use one to open a box from Amazon, of course it gets dull. This is why you have box cutters or pocket knives in addition to really good knives.

Erik