Domino 5mm Cutter cutting too small

[matttruiano]

anyone have any issues with the domino  5mm cutter becoming chipped/becoming damaged right away to the point where its not making appropriate sized mortices? I original thought that my tenons swelled since I haven't used them in a while. so I bought a new bag and realized that's not the issue.  So I just bought a brand new cutter and the first few were perfect. After just a few more plunges into red oak I was back in the same situation.  the only way to continue working is to sand down every tenon both in width and thickness to fit.
The reason why I bought a new cutter was because I was having the same problem with the old one (which only had a few uses out of it) could I possibly be doing something wrong? I have an 8mm cutter that does not give me any problems.

 

[ChuckS]

9/10 times such problem happens because the plunge is made too fast or the machine is moved before the cutter is completely withdrawn, or both (assuming dust collection is used). There's a learning curve in the use of the smallest cutter, if one gets used to using the bigger cutters not in a "gentle" manner. I've seen many domino joiner users making their cuts way too fast. One telltale is the chatter sound.

 

[Birdhunter]

It is really easy to knock the carbide tip off the 5mm and 4mm cutters. Once damaged, the mortises will not be correctly sized.

When I ruin one, it is always due to contacting the wood too abruptly. I’ve learned to move the Domino with my legs and not with my arms. It’s almost the same action as with a wood plane.

 

[Cheese]

Ya, I'd also check your technique. I've used the same 5 mm cutter for the last 5-6 years putting together oak trim around windows. Between oak, maple, mdf and fir there are probably 300-400 plunges on the same Domino cutter and it still works well. Like Chuck said, there is a learning curve. [smile]

[oops] almost forgot... [welcome] to the FOG.  [smile]

 

[matttruiano]

Does my cutter look like its damaged enough to be making that small of a cut? or would you think its mostly all user error.

 

[gvega9889@gmail.com]

I'd  try a very slow plunge and see if there is a difference in size.  If it's still the same then more likely the bit is the culprit.  You stated when the bit was new the mortise was the correct size, right?

 

[Birdhunter]

Here is a 5mm cutter right out of the box.

 

[Coen]

To be sure; you are not trying to get a 6mm domino into a 5mm hole?

 

[JimD]

I use CMT cutters.  I have not used the 5mm except for test cuts but all my CMT cutters work well.  I broke the first 14mm, however, but it was quickly replaced.  I did not jamb it in quick, it just fractured.  The replacement made several large slot mortises in a crib proect with no issue.

 

[greg mann]

Looks like you’ve lost the carbide tip. Either plunging too fast or allowing some movement while in the plunge. Since you have lost two now it makes me think user error, especially since the first few plunger were okay. The carbide is probably in the bottom of a mortise or somewhere on your floor. I feel bad about pointing the finger at you but 2 occurrences kind of rules out a bad brazing job. Like others, I have not experienced loss of size over many, many uses including in Ipe.

 

[ChuckS]

Not all is lost if you're willing to use your damaged bits with shop-made tenons. It's better than throwing those bits away.

 

[PeterK]

Yep the carbide tip is gone.
Had it happen in plywood as it kept changing cutting speed going through the plys.
I just cut way slower now and my bit now is a couple years old and still sharp. It is the only bit size I keep a spare for.

 

[Birdhunter]

i keep spares for all of my cutter sizes, but have only lost tips on 5mm and 4mm.

I think brazing the carbide tips onto the cutters is a way to produce affordable cutters, but it is a point of failure.

I wonder if solid carbide cutters would be significantly more reliable?

 

[jeffinsgf]

i keep spares for all of my cutter sizes, but have only lost tips on 5mm and 4mm.

I think brazing the carbide tips onto the cutters is a way to produce affordable cutters, but it is a point of failure.

I wonder if solid carbide cutters would be significantly more reliable?

Brazed tips allow a more resilient shaft. I'm afraid solid would fracture at the shaft, rather than at the tip. Notice the braze is still in place on his broken tips. The carbide broke...not the braze or the shaft.

 

[Stunt]

Cut slow.
My only advice I don't see here is when cutting try and use two hands on the Domino. Doing small pieces I've found I try and hold the work piece steady on the bench with one hand (same have on the handle of the DF500) and one to plunge.
This sometime caused the Domino to tip. I'd hear that chatting sound. Now I try and clamp my pieces down then one hand only in the Domino handle and one on the rear plunging. Straight in and out. Nice and slow.

 

[RustE]

I wonder if solid carbide cutters would be significantly more reliable?

Probably not for how the cutter moves around in the mortise.  As previously stated, the shaft would have less ductility and probably fracture.

What might be a better solution is to induction harden only the tip of a one-piece cutter.  The hardened tip would be better than a HSS cutter but still would not be as durable as a carbide insert.

 

[Cheese]

Brazed tips allow a more resilient shaft. I'm afraid solid would fracture at the shaft, rather than at the tip.

Exactly...while solid carbide may be stronger it's also more brittle. The HS steel Domino body allows for more ductility (flex) while the brazed carbide inserts allow for longer life. Even if it were possible, then there's the pricing issues for solid carbide. [jawdrop] [jawdrop]  The current $40 price tag would zoom to $150-$160+.