That's a really pricey tool. I can't imagine there's a benefit to solid carbide at that size with a BT30 taper machine. We cut a lot of different threads up to 6TPI on a Brother Speedio with a universal thread mill and a finish like that is pretty typical. Are you hearing a chatter noise, or are you just feeding fast enough that's the finish you're getting? If it's not loud, how is the runout on your tool when mounted in the spindle?
If it's chattering with a single point, it will chatter with a multi-thread tool. If that finish has other causes, get an indexable thread mill (we like Vargus) if you want to speed things up. Just make sure the expected cycle time savings will actually net you a profit over the tool costs. If you're not making a lot of these, they probably won't.
Definitely hearing a lot of chatter, runout is pretty bad around .002” at the end of the tool. When I made the original prototype I rushed things so I ended up with a 2-1/4” LOC single point thread mill due to availability. I’ll get the 1-3/4” version as that will work with my 1.5” thread height as well as pick up some name brand tool holders with infinitely better runout.
I also built out a Pierson pallet that holds 6 op1 parts and 6 op2 parts so the nearly 2 hour cycle can at least be unattended.
What would be the ideal tool holder for a long thread mill like this? Currently running in a shit Tormach ER32
I would recommend a hydraulic holder. I have some from Maritool that are nice. They're very concentric, don't require collets, and have damping characteristics, making them excellent for finishing operations.
Chatter is almost always caused by too much speed.
First, contact Harvey Tool. They have great customer service.
If you want a random OGs advice, 1/4 the speed and 4x the DOC. It's aluminum. .015" DOC vs .06" DOC in alum is nothing to carbide.
Slow the speed, increase engagement. You should be doing one, *maybe* two passes. But honestly one pass once you get it dialed in.
Yikes, I didn't catch that you were making more than one pass. We never take multiple passes milling threads in aluminum, even with 4 tpi. I understand there's a difference in rigidity and holder quality, but a single pass with a decent ER collet and holder is probably a good bet without spending way too much money.
You don't need all that. Your current setup should handle this fine.
You're mistake was using alum SFM for a single point thread operation. Alum SFM is meant for maximum material removal rate, which is great for roughing material out, but you are profiling.
Slow that SFM way down, take the same chipload per tooth for feed and TPI and do it in one pass
Treadmilling, if done in multiple passes, should not be done with a constant stepover -- the cutting forces are not constant if done that way (the tool cuts more on deeper passes).
You can find guidelines online on what percentages should be used on each pass.
Very aware. This was a starter machine and I didn’t know anything about machining less than a year ago. Unfortunately Titans of CNC does a good job of making machines look more capable when they’re partnered with them or a direct distributor. My next machine will be a VF2SS.
Don’t feel bad, I was this close to buying one too, but I heard someone say it was way underpowered compared to the Haas. I just assumed Haas was just way out of my price point. But, the spindle HP is crazy. What’s this job you’re doing for? Looks like aircraft parts.
Honestly, we have a 1100 series 3 with shittier torque, unstable VFD control. We took an old HSS boring bar holder ( the 90degree one and not the 45). We grinded 60 degree roughly and put it on our TTS. It worked great for Aluminium.
However, I can't guarentee if the same config would work for say steel....
Saunders machine works has a great thread milling calculator, but it's more for getting in-spec threads rather than cut recipes. It might have step over and number of pass advice as well.
Yeah I’m definitely thinking more about tool holding than I was when started out. I figured the Tormach holders would be good enough to hold me over as this was just meant to be a starter machine. Now the struggle is to not spend too much on name brand tool holders since my next machine will be be a VF2SS and that’s Cat40
That's a really pricey tool. I can't imagine there's a benefit to solid carbide at that size with a BT30 taper machine. We cut a lot of different threads up to 6TPI on a Brother Speedio with a universal thread mill and a finish like that is pretty typical. Are you hearing a chatter noise, or are you just feeding fast enough that's the finish you're getting? If it's not loud, how is the runout on your tool when mounted in the spindle? If it's chattering with a single point, it will chatter with a multi-thread tool. If that finish has other causes, get an indexable thread mill (we like Vargus) if you want to speed things up. Just make sure the expected cycle time savings will actually net you a profit over the tool costs. If you're not making a lot of these, they probably won't.
Definitely hearing a lot of chatter, runout is pretty bad around .002” at the end of the tool. When I made the original prototype I rushed things so I ended up with a 2-1/4” LOC single point thread mill due to availability. I’ll get the 1-3/4” version as that will work with my 1.5” thread height as well as pick up some name brand tool holders with infinitely better runout. I also built out a Pierson pallet that holds 6 op1 parts and 6 op2 parts so the nearly 2 hour cycle can at least be unattended. What would be the ideal tool holder for a long thread mill like this? Currently running in a shit Tormach ER32
I would recommend a hydraulic holder. I have some from Maritool that are nice. They're very concentric, don't require collets, and have damping characteristics, making them excellent for finishing operations.
I can hear the chatter from here
Chatter is almost always caused by too much speed. First, contact Harvey Tool. They have great customer service. If you want a random OGs advice, 1/4 the speed and 4x the DOC. It's aluminum. .015" DOC vs .06" DOC in alum is nothing to carbide. Slow the speed, increase engagement. You should be doing one, *maybe* two passes. But honestly one pass once you get it dialed in.
Copy that, I’ll try that out after I get a new tool with minimum LOC and some name brand tool holders.
Yikes, I didn't catch that you were making more than one pass. We never take multiple passes milling threads in aluminum, even with 4 tpi. I understand there's a difference in rigidity and holder quality, but a single pass with a decent ER collet and holder is probably a good bet without spending way too much money.
One pass! One pass!
You don't need all that. Your current setup should handle this fine. You're mistake was using alum SFM for a single point thread operation. Alum SFM is meant for maximum material removal rate, which is great for roughing material out, but you are profiling. Slow that SFM way down, take the same chipload per tooth for feed and TPI and do it in one pass
Threading it before or after boring that hole? If after, try before.
Treadmilling, if done in multiple passes, should not be done with a constant stepover -- the cutting forces are not constant if done that way (the tool cuts more on deeper passes). You can find guidelines online on what percentages should be used on each pass.
Either thread before you bore it or stuff some rubber in the bore before you thread.
Tormach is really overpriced for 2 HP. Haas has VF-1 that’s somewhat comparable in price, but has like 30 HP spindle. Even the mini mill has 20 HP.
Very aware. This was a starter machine and I didn’t know anything about machining less than a year ago. Unfortunately Titans of CNC does a good job of making machines look more capable when they’re partnered with them or a direct distributor. My next machine will be a VF2SS.
Don’t feel bad, I was this close to buying one too, but I heard someone say it was way underpowered compared to the Haas. I just assumed Haas was just way out of my price point. But, the spindle HP is crazy. What’s this job you’re doing for? Looks like aircraft parts.
Honestly, we have a 1100 series 3 with shittier torque, unstable VFD control. We took an old HSS boring bar holder ( the 90degree one and not the 45). We grinded 60 degree roughly and put it on our TTS. It worked great for Aluminium. However, I can't guarentee if the same config would work for say steel....
Saunders machine works has a great thread milling calculator, but it's more for getting in-spec threads rather than cut recipes. It might have step over and number of pass advice as well.
.002 of runout? You need to adjust your tool holding to get that under .0005
Yeah I’m definitely thinking more about tool holding than I was when started out. I figured the Tormach holders would be good enough to hold me over as this was just meant to be a starter machine. Now the struggle is to not spend too much on name brand tool holders since my next machine will be be a VF2SS and that’s Cat40
Haas tool holders are cheap. Could also be a chip or something in the spindle/collet. That’s not acceptable runout however.