CMT Spindle cutter head

[silky oak]

Hope this is of interest to some of you woodies,

I purchased a CMT cutter head approx 2 yrs ago,I have not used it to much,10 /20 times,maybe 1/2 hr duration,anyway the other day I had cause to use it,I set it up in the same way,checked and double checked,all guards on,now i'm a cabbie of 40 odd yrs,so when I switch on a spindle moulder I crouch down below the head for obvious reasons,in this case it paid off for the first time in those 40 odd yrs because all I heard was an almighty bang and so the cutters and the head flying everywhere,after I picked myself up and stopped shaking I inspected what had happened,the housing had blown completly out of the head leaving me with a $268.00 head that I can throw in the bin,and a bent spindle shaft,but most of all a very close bad injury.

When I approached the company I was told that my warrenty had run out,to which I replied ,mine nearly did to.

He then told me that he would give me 10% off a new head.
Really fella's I believe in these warrenties to protect the company,but thats as much as saying after the warrenty, it is'ent any fault of our if you kill yourself.
I would appreciate all feedback on this one cause I don't think it's good enough.

A very lucky woody

[QldWoodie]

You surely are lucky! I guess that caution just got some reinforcement.


the housing had blown completly out of the head leaving me with a $268.00 head that I can throw in the bin,and a bent spindle shaftI'm trying to understand what happened. I take it the shaper cutters didn't come off the cutter head, but that the cutter head either fell apart (how?) or got unbalanced or came loose from the spindle shaft and then hit something prior to further disintegration? Is the inside diameter of the cutter head the same as the spindle shaft or do you use reducers? For example, my cutter head has 30mm inside diameter but my spindle shaft is 1 inch, and I can see a problem if say the bottom reducer was missing or not centered when I tightened up.

I'd certainly appreciate learning more from your near-catastrophic experience. Can you post some pictures?

Qw

[silky oak]

To ensure that the cutters stay in the housing a wedge shape block is used between the cutters and the inhibitor as you tighten up the wedge shape block with a 4mm head allen key the cutters become jammed in.They say that what I did was tighten it up to tight and caused an airline crack,when I switched on it blew out the housing.

So the moral of the story is leave it slack.

[silky oak]

I will post some pics Qld Woodie

[John Saxton]

This is an area of concern "silky oak" and I too await your pics of the cutter head.
CMT do not offer up advice on torque required on tightening the knives and may find themselves in strife if they fail to address this moreover if the cutterheads can be subjected to minimal pressure.

I also have a set with knives and I'll duly approach with caution on further use with it.
However it is generally known that only well tightened knives in cutter blocks as a standard will suffice but if the cutter block is alloy or aluminium then stress's will take their toll over time.The older and better known sets are machined steel and are of course able to withstand the stress's implied.

Go out and buy yourself a lottery ticket Silky Oak ..you owe it to yourself.

Cheers :)

[QldWoodie]

.... it is generally known that only well tightened knives in cutter blocks as a standard will suffice Yes. I recently bought a new cutter block (Witox brand - supposed to be top quality according to Gregory Machinery) and there were no instructions on degree of tightness for this wedge. I use the allen key supplied. And recognizing that this wedge is what stops those cutters from coming off I (like all of us, I'm sure) have erred on the side of tightness. Now CMT are saying that if we overtighten we are likely to induce hairline cracks and the block could come apart on start-up?

Please keep us informed of any developments, particularly response from CMT. CMT should replace the cutter block IMO regardless of the warranty period. After all it didn't wear out!

Qw

[boban]

I would say you have further redress against this company. You have statutory rights beyond what they are prepared to give in the way of warranty. It has to be fit for its purpose as well as dealing with OHS issues.

Courts are too expensive but I would suggest a complaint to the Department of Fair Trading and Workcover in your state.

Give them hell....you have a right to be angry. What would your family be left with if the thing hit you. 10% off a new cutterhead....how generous. I was going to buy a CMT cutterhead set (kitchen door set) but after reading this, I think I'll look elsewhere.

[Gaza]

U are not the only one to have a close shave with a spindle, Today we were using our spindle at work with power feed and all, we were pushing 3x1 softwood though it then bang it all goes wrong.
The cutter we were using was being held in postion by collars, the cutter it self is soild tool steel (6mm thick) which has a rebate this rebate locks into the collar that has a pin in it. (one pin per knife).

One of the pins broke and the knife slipped forward till it hit the fence the spindle jamed till the knife broke, it was then spat to the back in to the dust hood. (lucky).

On top of this it broke the shaft away from the drive shaft on the motor, a 6mm pin had snapped.

Dont be stupid like me and use collars, use serrated back knifes, profiled to detail by your local saw doctor. (in syd Henry bros etc...) While not being as cheap as the CMT cutters i dont like the reports of the head breaking. It may be a manufacturing fault, they should give u a new one as its not a warranity issue its more a quality issue.

Thats my $0.02 worth

[silky oak]

You to were the lucky one also Gaza,Ive used those blocks before ,and they can make a mess when things go wrong,

I have just recieved a reply from CMT USA saying that they are sorry to hear that I had problems with one of there products,and they have forwarded the message on to there technical Dept in Italy.I wait their reply and I will keep you all posted.

I will have the pics on here tomorrow.

SO

[silky oak]

Her are the pics of the cutter head.

SO

[Wood Butcher]

I use similar cutter heads at work. Because of the centrifigal force exerted on the wedges you do not need to tighten the grub screws excessively. the wedge gets thrown outwards when the cutter starts to rotate further locking the cutters in place. But, considering that the bodies of those are supposedly made out of high grade alloys I cannot see how you could cause hairline crack unless you used a rattle gun to tighten the screws. I think that CMT has a lot to answer for in this case.

[silky oak]

Recieved a email from CMT Italy 8 days and 1 reminder.

They say that they cannot comment untill they have inspected the cutter head,and they say that I have to send it to Italy.


Regards

SO

[Iain]

The onus falls upon the seller of the unit not the manufacturer (in this instance), take it back and tell them to send it back to Italy or approach your consumer affairs.

Looked at your address, Office of Fair Trading up there, heres a link
http://www.fairtrading.qld.gov.au/oft/oftweb.nsf

[John Saxton]

As a consequence of "SILKY OAKS" pictures I will now resort to using my other set of machined steel(coming in late here have been away from home again ...sigh) cutter head and cutters until such is the response eagerly awaited by their OZ clientele from CMT. :(

For the outlay some of the steel machined cutter heads are looking more attractive ...better than adding grief to your own family :mad:

Cheers :)

[silky oak]

Sent the cutter head to Italy today,at CMT expense,for there inspection and comments.
I eagerly await there response,and I will keep you all posted.


SO

[silky oak]

I recieved a reply regarding the cutter head,it seems that it was my error according to CMT,I have written back to ask what they will do about the problem apart from replacing the part.

I think everyone who uses this tool would want to know how safe it will be in the future,I have also asked ,if they are going to take responsibility for the repairs to my spindle moulder.

Email attachment from CMY

[silky oak]

Recieved email from CMT.

As I imagined they imply that the error is down to me,they say after inspection,they conclude that the cutter has crashed into something ,or that the wedge screws have been tightened to tight,but to Quote them (To keep our client happy we will send you a new cutter head) they refuse to take responsibility for the damage to my machine, or take onboard the flow in the aluminium being able to break.

What next I ask myself

SO

[silky oak]

CMT have told me that they are not resposible for the damage to my Spindle moulder shaft.

I was just wondering if anyone else here has had simaler experience.

CMT say that I tightened the cutters in to tight,but I wouldent have imagined that you could by hand with a small allen key.If so I dont believe this to be a very good tool.

Any comments.


SO

[Gaza]

Have you changed your shaft yet?

i had to change one the other day at work took longer to get the big nut off with a plumbers wrench then to change the whole thing over. i was suprised how easy it was.

[CC Sawmilling]

I was about to buy CMT cutters for my machine this week now re considering. any advice on better! cutters ?

[Greg Q]

You might try Leuco or Leitz brand, Omer and Pela are supposed to be good too. Felder sells re-badged Leitz that is pretty good. They also have alloy
heads under the "Hammer" range, but I think I'll stick with steel.

I bought a nice looking cutter on eBay from the UK, but the seller would not
retreat from his 50 pound shipping fee, so watch out for that if you go down that road.

Can anyone tell me if the CMT insert cutters are actually carbide? Carba-Tec seems to think so, but every other make is HSS.

Greg

[Siver Ash]

The same thing just happened to me. Unfortunately the chunk that broke hit my arm.
Lucky to still have it.(my arm)
I don,t want 10% discount on another one.
I will never put on another alloy head.
This thing blew apart by itself, there was no load being applied at the time.
The wedges were only done up hand tight.
The discoloration in the break would indicate a flaw in the metal.
How many more "killer bombs" are out there, I wonder?
Photo's will follow when I figure out how to download them.

[fletty]

Hi Silverash, welcome to the forum and I hope you are OK!
I have a spindle moulder and a CMT cutter head ... and the whole thing scares the daylight out of me.
The concern started on day 1, I bought several JET machines at the Sydney WWW Show and Major delivered and assembled them all (thanks Paul).
The moulder was the last that I started to 'play' with. It has a reversing switch and was left for me with the switch in the REVERSE position. I turned the moulder on and satisfied myself that REVERSE was the right direction to feed workpieces from right to left as I do for my router tables. This worried me because, if I had set it up myself, I would probably have put the first piece through in FORWARD and probably lost my nerve for ever as the workpiece shoots out through the shed wall.
I used it almost exclusively with large router cutters at 10000rpm and slowly built up my confidence before buying the CMT cutter head and some blades and limiters. I did this because my experience with CMT router bits and blades was excellent. Then I saw this thread and started to lose my nerve!
so, back to router bits...
the next burst of bravery had me buying a single piece cutter, steel body, tungsten faces, no kickback design, and fitted it to the spindle to make the top for 'Lucy's Box'. Refitted the spindle shaft rather than the router collet ... and found that the single piece cutter was set up for rotation in the opposite direction and I'm not going to start feeding from right to left!
Are these machines and cutters really beyond the scope of us weekend warriors?
Fletty

[Stringy]

after investigating these cutterheads I purchased a IVA steel cutter head from Henry Bros saws in Sydney for about $100.

The IVA, CMT, Freud and others all take the same cutters and limiters, with absurd price variations. Paid $24 a set (cutters and limiters) for Freud cutters which I have had no issues with other than they had to be ordered from Italy.

Also have Freud RS 2000 and RP 1000 cutter sets which I am pleased with at only $275 a set.