Cutterhead replacement questions.. Tersa / Byrd / Terminus

[Rick Fisher]

I am going to re-tool a 16" jointer and a 20" planer.. Both have 4" diameter cutter heads.

My present Jointer has a Tersa head ( not the ones above) .. Planer has a helical head. I actually prefer the Tersa over the Helical due to the ease of blade changes, especially on the jointer.

Anyway.. I got a quote on a Tersa head made by MBM and was actually shocked how expensive it is ..

A Tersa is $1500 Euro's ..
Which is about $2200 Canadian..

The Byrd Cutter head is about $1900 ish..

What I am wondering is .. Are Tersa heads only made by Tersa or MBM .. I would have expected that lots of companies would make Tersa style cutterheads ?

[Glenn Ancona]

Rick,
Unbelievable score on those two machines! I followed that thread and can't believe no one told you suck!!!
I believe that TERSA MBM is it - there's not much of a market but hopefully some one with more knowledge will chime in. Our 24 inch planer has a tersa It's the fastest blade change of any machine we own. once you have done it once you can change it quicker than a skill saw blade.

$ 2200 Canadian seems pricey so keep us posted. After hearing of you edge sander find a while back and now these, Im sure you will find them cheaper as deals seem to find you ?!? good luck on the rebuild. glenn

[jack forsberg]

Hi Rick

Can i asks what you don't like about the heads in there now? If i am not mistaken there a 4 knife gib head. A new head IMO has benefits for a planer as you would never need to adjust the pressure roller or bars as a knife change set the knifes in the same cutting circle every time. I guess my thinking is why a jointer as your going to send your work through the planer after. If your a full production shop i can understand. I just wondering if this is just not a case of new is better and i want to upgrade my machines? I guess What i am saying is I would take that money and get a used thickness sander as its more a finishing machine than a jointer or planer. What are you doing with the Old heads? I am seeing on a regular basis 37" sander going for the price of one of your heads. BTW you did real good on that deal Rick

jack
English machines

[David Kumm]

Rick, I'm with Jack here. I run an ITCH head that leaves a great finish but it is sweet to run a last pass through the WB with 180. If changing knives is really a pain you could look at the ESTA system for a few hundred and put the money into a WB. Single head combo unit Sandya 24" goes 3000-4000, any 37" might be some more but gives you tons of flexibility. Dave

[peter gagliardi]

I have a friend who has Martin machines with Tersa- he loves the quick change, but knife life he's not thrilled with. My suspicion is that the knives are so small that there is not enough steel there to dissipate the heat and they dull quicker than the regular planer blades.
I on the other hand sprung for new Terminus heads on my jointer and planer that are 90 and 70 years old respectively, the cut is phenomenal , and I can change knives in about 5 minutes and be back to work. I do however note that again, knife life is not as good as regular planer blades. The Terminus blades are about twice the size of the Tersa, but still not enough to dissipate the heat as well as old stuff. When I bought mine, they were about $150.00 per inch of cutting edge - so a 16" head was $2400.00 for a 4 knife setup. I really don't like the cobbled look of the Byrd head, but they say they work well.

[Peter Quinn]

Those prices seem about what I would expect give or take a little exchange rate variation. I've never used tersa heads, we have a bunch of terminus heads at work, I've heard of companies knocking off the knives at a savings but never the heads. Terminus leaves a great surface with good knives, blade changes are very quick relative to traditional knives. I have Byrd heads at the home shop, not as good a surface finish, but much quieter and less tear out on challenging grain. Not sure a full knife rotation on a Byrd head would be what I'd call quick, just looking at it there are a lot of chips to remove, clean, replace and torque properly. Could take longer than traditional knives on a per instance basis, I've been on the original side for over 2 years and I'm just getting ready to turn a few due to nicks.

Are you saying the Griggio planer has the spiral head? I'm wondering if that is the spring steel one piece blades such as used on older Casadei Machines? Those leave the best surface I've ever seen on a planer......for about 20 minutes, at which point the edge starts rolling and chipping. Not much blade life at all, every little spec of sand or hard knot does them in, and the knives have gotten real expensive of late, like $240 per change for a 2 knife head. They are disposable and a real bear to change, we let them go WAY too long between changes due to $$$ and PIA factors. Oh but when they are new, its glorious, like a freshly hand planed glowing surface smooth like butter. Certainly serviceable in the short run, particularly in a one man or small shop.

[David Kumm]

Rick, I forgot you all ready have a Sandya Win. Dave

[Erik Loza]

I would go for the Byrd head. Yeah, it is a grip of $$$ to buy just a Tersa head for a big machine like that. I likewise prefer actually using a Tersa machine over spiral/helicals but it's an arm and a leg to buy just the head. Doesn't make any sense unless the machine came with it in the first place. Just my 2-cents as always.

Best,

Erik Loza
Minimax USA

[J.R. Rutter]

Congrats on the machines.

I have Terminus heads for my moulder, Tersa in the jointer, and Byrd in the planer. If you want a "finished" cut, the full width knives are nice. But they do not stay fresh for very long and get very noisy as they dull, so budget for fairly frequent changes. For the jointer and planer, I would personally go with spiral insert. You get longer life, quieter operation, and close to the quality of a straight knife. As an aside, I don't think that EU regulations allow this type of head in a jointer due to the remote possibility of a fractured insert being ejected out the top of the machine.

The only time that I have a finish cut off the jointer/planer is on edge grain like frame parts, door edges, etc. Any head is capable of doing this. The Tersa or Terminus is slightly better for this until it gets a bit dull and then is more prone to tear out in tricky grain.

[Jeff Duncan]

I might look into wether you can get an OEM grinder for your planer? I have one on my SCM and I would never go back to any other system. They're harder to find for jointers so I'd probably go with the Byrd head there, unless there's some special reason you want a Tersa head?

good luck,
JeffD

[Rick Fisher]

Really great feed back .. I googled Esta .. Never seen it before.

I am getting rid of my present jointer and planer after the restoration is done.. My existing jointer has a Tersa.. Existing planer is helical insert..

I actually prefer Tersa but as Eric said, I cant see how the cutter head alone is worth that kind of money.

I am going to look into the Esta system.. I am going to the woodworking show next week, hopefully they will be there, I need to get this happening ..

[Peter Quinn]

Reread your OP Rick, I take it you have straight knives in the Griggio planer? Then the esta system makes sense to me. I misunderstood and though you might have one of those Italian spiral heads with flexible one piece knives. Couldn't use Esta there.

[David Kumm]

Rick, ESTA has a little of the same thin knife problems on a planer that big but they make high quality knives that are reasonably priced. Felder used that system and still does although they are moving to their Silent Power spiral head. Talk to esta or the disposablade people about whether the jack screw or cutterhead type are more appropriate to the machine. It may be in that application that the holders that index off the head might work better. I don't like those on a jointer but you have to be careful you don't get crud in the slots whereas the planer might be fine indexing off the head. Dave

[Rick Fisher]

Hmm.. Hopefully ESTA will be at the Woodworking show in Vegas.

The Byrd Cutter head for the Jointer is 4.64" in diameter and weighs 62 Lbs ..
Apparently the planer is the same basic design except for length.

[Joe Calhoon]

We have Tersa in our four sider, planer and jointer. I found the M42 disappointing unless just running softwood. We have gone carbide on the four sider and planer. We can get 4 to 6 months on the four sider before turning the knives depending on how busy we were. The cut when they start dulling is still very good. Carbide prices are scary going in but it works out to be the best value for us. I am in the process of trying some diamond coated standard Tersa knives from Zuani and will see how that works. The cost of the coating and knives is less than carbide.

We tried Esta knives in a SCM planer several years ago and found them not so easy to change, poor cut quality and they dulled quickly like the standard Tersa. I felt the straight knife with grinder was better than that. I would not go back to a straight knife machine after having Tersa.
Joe