Breaking cutting bits

[Oldtrainerguy]

My machine keeps breaking cutting bit. head pressure is good and everything seems fine. When doing a project the bit cuts then slows for a second and snaps.
After the break it tells me to check cut motor.
It only occurs when using the 1/8th. 3/16th is fine, carving and centerline text is fine.
Broken 3 bits now and its getting expensive.
Have Version C updated to 1.177 software.
I clean often
Any suggestions?

[cnsranch]

Make sure you're making multiple passes - one pass at 3/4" cut and you'll break it. IMHO, never more than 1/4" per pass.

Also, if you put a large feather around the cut-out, the bit will be cutting less wood as well.

[Oldtrainerguy]

Using Pine wood. Round box project. Bit barely get going before the problem occurs

[Old Salt]

see if the head has any movement in it , you may have a lose bearing or bit holder . use tape on bottom of board to grip tracking wheel. be sure and stay under rollers add the 7 in to the board
Just a few of the things to check. but good start.

[Ike]

The position of the bit in the chuck has a lot to do with it also. Of course with the CT the built in holder can be inserted one way, but with the 1/4 sleeve you can not have enough shank installed. Plus are you using 3/4" boards and in the designer assigning 3/4" or 1" cut? Set too deep and you break bits! I was cutting 3/4" boards and assigning them as 1"

Ike

[Oldtrainerguy]

I will make sure the chuck is installed all the way into the spindle. The assigned depth was 3/4 on a 3/4 board. Maybe the chuck was not all the way in.
Will keep ya' ll posted.

[Digitalwoodshop]

I bet you a cold beer that that slow down you see it the feed rate going from first gear to 2nd gear and SNAP.....

Assign the 1/4 inch ball nose bit BUT use the 1/8 inch bit and it locks the feed rate into 1st gear.

That is what I do.... Takes longer.... But smoother cuts and no more broken bits.


AL

[mtylerfl]

I bet you a cold beer that that slow down you see it the feed rate going from first gear to 2nd gear and SNAP.....

Assign the 1/4 inch ball nose bit BUT use the 1/8 inch bit and it locks the feed rate into 1st gear.

That is what I do.... Takes longer.... But smoother cuts and no more broken bits.

AL

Hi AL,

I don't think he can assign a 1/4" ballnose on a Cut Path...three choices...1/16" cutting, 1/8" cutting and 3/16" cutting - no 1/4" ballnose. I haven't tried the 3/16" cutting bit yet, so I can't say whether he could assign it then actually insert use the 1/8" cutting, whether it would have a slower feed/speed rate or not. Maybe!

[gashawk]

The drive belt in the ztruck can tear, allowing extra movement for some bits to drill down. Try lifting and lower the ztruck by had, checking for loose travel.

[Oldtrainerguy]

Belt drive is good but it may be the transition from first to second. Using the 3/16th is good. The round shell box project was the culprit. Didnt know if I could change it since it was a "free" posted carve. I left it at the 1/8th because the 3/16th would cause the cuts to be bigger and make the ring smaller causing it to break.