Changing Spiral Cutters - Torx Bits Breaking

[Mike Chalmers]

Decided it was time to rotate my cutters on my jointer. All was well until it was time to install the cutters after cleaning. Torx bits that came with the machine twisted and/or broke at about 25 ft lbs. Went to Canadian Tire and bought "better" quality torx bits, this time ones with 3/8" socket. Broke at 35 ft lbs. Tightened bolts as tight as I could with bits I had and a T handle. I only worked on one row.
How do I get bolts to 50 - 55 ft lbs (Grizzly manual recommendation)?

[John C. Wilson]

Mike, mine did the same on my 8 inch jointer, broke every bit that came with the machine.Bought a new pack of 20 as I have to change my 20 inch planer as well. I got my jointer screws as tight as I could, doubt if they are all exact as should be pressure wise but jointer is working fine.Grizzley bits were very soft. Good luck.........John

[Van Huskey]

50 - 55 ft lbs (Grizzly manual recommendation)?

Inch pounds, my man, inch pounds!

Or ~6 newton meters if that works better fer ya.

[Ken Fitzgerald]

Inch pounds, my man, inch pounds!

Or ~6 newton meters if that works better fer ya.

This an important detail!

[Robyn Horton]

Yes not ft pounds inch pounds for the cutters

[Mike Chalmers]

Dohh! That may make the big difference. Now, what is that in Ft Lbs, as that is the markings on the torque wrench? An on line converter I used says about 4.25 ft lbs.

Don't worry, I feel like an idiot.

[Van Huskey]

Dohh! That may make the big difference. Now, what is that in Ft Lbs, as that is the markings on the torque wrench? An on line converter I used says about 4.25 ft lbs.

Don't worry, I feel like an idiot.
It is easy to read a number and let your brain insert the units. Honestly, most 1/2" torque wrenches are going to be rather useless at such a low level. You will need to get a torque wrench or torque driver 50 in/lbf is more toward the middle of the range vs the extreme edge. The conversion is simple divide in/lbf by 12. Many people don't bother with a torque wrench and just tighten them down. I am a cyclist so I just use my Park torque wrench, Performance Bicycle et al sell cheaper versions. I mention these since most of the ones sold in the mechanics tool word tend to me more expensive. Park also sells preset t-handle drivers for about $40. Again they tend to be cheaper than ones sold through other channels. If you get a Park (or any other) preset you need the 6nm version if they are metric.

[Vinito Caleb]

Many people don't bother with a torque wrench and just tighten them down

Yea. I use inserts in the metal machine shop every day and they spec a torque setting, but personally I never bother with it. I get a lot of practice so maybe that makes a difference, but if you pay attention and just try to get them all close to the same feel when you torque them, it should be fine. Just snug them about as much as you think a screw that size should have and you really should be golden, i.e. pretty darn snug but well to the safe side of not stripping or breaking anything.

I don't want to steer a guy down a bad path, but for what it's worth when I need to index my inserts I just plan to snug them down manually. The important thing, more than a torque setting, is to be sure the seat and insert are both whistle clean. Use a solvent, even carb cleaner or something, and dry it well. Lastly, blast a bit with compressed air if you have it. One little fragment of sawdust will tilt the insert a bit and probably affect the finish to some degree (maybe not significant, but better to install them clean regardless).

Nothing wrong with using a torque wrench of course if you don't feel secure otherwise. I'd also recommend that you also apply just the smallest amount of anti-seize on the threads as well, which not only helps removal the next time but also lubes the threads for accurate torquing. Just don't apply too much - you only need a bit of a film on the threads when you're done.

[Ken Fitzgerald]

Van is correct. The normal 1/2 drive torque wrench or even the 3/8" drive torque wrench is pretty inaccurate at 4.25 Ft Lbs. Usually, you want to be operating in the middle of a tools range whether it's a multi-meter or a torque wrench.

There are a number of relatively cheap inch pound torque wrenches available out there. I bought one just for this purpose.

After changing and aligning the blades on my Ridgid planer, I can't wait for the motor or something major to break so I can get a replacement with a spiral head!

[Grant Wilkinson]

I rotate and change out the inserts on 2 commercial machines and never torque them. I use a 1/4" drive ratchet with a bit inserted and hot glued into a 1/4" socket. So far, so good. :-)

[John K Jordan]

I rotate and change out the inserts on 2 commercial machines and never torque them. I use a 1/4" drive ratchet with a bit inserted and hot glued into a 1/4" socket. So far, so good. :-)

The problem with having experience is you have the experience. And others don't! Someone not used to how it feels may tighten too little, or more often, too much. (I've seen lug nuts, for example, WAY over-tightened.) I keep torque wrenches both large and small and I do tighten things by hand for the most part, but I think the torque wrench is a wonderful way to learn the feel, especially for someone without decades of mechanical experience.

When I was a steel inspector I had to shinny along shaky i-beams 7 stories in the air and check the torque of big bolt connections. The spec on these was 250 ft lbs which required a torque wrench about 3' long. Good fun!

JKJ

[J.R. Rutter]

I rotate and change out the inserts on 2 commercial machines and never torque them. I use a 1/4" drive ratchet with a bit inserted and hot glued into a 1/4" socket. So far, so good. :-)

Yeah, I just use a 12v impact driver that has adjustable torque and set it in the middle of the range. I did use a 1/4" torque wrench initially though to get the range approx correct. From what I have seen on reviews of cheap torque wrenches, it it chancy to really trust them. If you tighten as much as is possible with a screwdriver type hand tool, then you are good to go.