Like a good chef, a good machinist does a lot by feel and experience. These things can’t be learned in a few hours or even days – it takes years.
When it comes to CNC machines, sometimes the sum equals more than its parts – but many times the parts generate more than its sum. We spoke to several prominent engine builders who have recently purchased a CNC machine for their shop and asked them the age old question: Why’d you do it? We also asked what kind of impact adding such a significant piece of equipment has had on their businesses.
Chad Mullins of Mullins Race Engines says that while it’s not easy to make the transition to a CNC machine, it’s worth the effort. “No question, when you’ve never seen a CNC operate and you bring one into your shop that it’s going to take some time getting used to it. We’ve had ours a year and we’ve been able to develop three different lightening programs on engine blocks, which is a very difficult thing to do. It’s not just a novice CNC operation. For what we’ve done, we’ve probably exceeded what many people could do in a year’s time.”
Mullins, who recently bought a Centroid CNC that does both 4- and 5-axis machining, acknowledges that a lot of people are intimidated by the technology and complexity of a CNC. “A lot of the automotive guys are used to dial indicators and not keyboards. Heck, I’m 36 years old and I’m almost too old for this [CNC]. When I went through school I didn’t get as much computer training as the kids do today. The guy we have working this machine is in his 20s so he was more up on the technology from the start.”
Andrew Rosa of Rosa’s Cycles in Long Island, NY echoes that sentiment: “I’m 55 years old and have a lot of computerized equipment like our dyno bench, flow bench and so on. I came into this business long before there was an Internet or any of this computerization. My opinion on it now? We can’t be without them. We have four main computers throughout the place and nothing would run without them. The truth is however, you could take a perfectly good running toilet and put a computer on it and it wouldn’t work anymore. You’re at the mercy of whoever is supporting you.”
Rosa, who recently bought a Red Rhino 5-axis CNC from Millport, says getting started is the hardest part. “It’s a tough learning curve overall, especially when you don’t have a background working on Mastercam, and I’ve never had a CNC machine before. My dyno and flow bench are Windows-run machines, but everything else in the shop is operated by sight, sound and feel – mechanical.”
Not many motorcycle shops have the capability to port heads or do any machine work like Rosa. “I’m a full service machine shop and we have a dyno, so we do tuning and testing in addition to doing work on the Harley-Davidson engines.”
Rosa says he doesn’t need to learn everything that the machine can do, he only needs to know how to cut cylinder heads for Harleys because that’s all he does. He only uses the head porting machine to turn out ’99 and up twin cam Harley heads – the lower volume stuff he still ports by hand. “There aren’t enough other Harley heads, like say, Evolution, that we come across. We still do those by hand. I just did a couple of sets of Shovelheads, and when we get them we do them by hand. For us, it doesn’t warrant scanning and retooling to do these cylinder heads. I don’t think I do four sets of Shovelheads a year where I need to port them.”
Pat McCreery of Nyes Automotive has three Rottler CNC machines – the HP6 hone, F68A 4-axis CNC block machine, and he just recently purchased the P69, which is a 5-axis cylinder head porting machine. Although he had no experience with CNC when he bought his first machine a couple of years ago, he says Rottler provided all of the necessary training for him to get up and running very quickly.
“When we bought the F68 about 2 ½ years ago, I had zero CNC machining experience – none. My brother had a little experience with one at another shop but it wasn’t much. Rottler’s claim is that they can take anyone with little or no experience on a CNC and have him doing it in no time. That was the case with us, and in my opinion they lived up to their claims.”
McCreery says you don’t have to have that much experience but you have to be reasonably computer literate to begin with to learn to operate a CNC. “You really have to be comfortable with both computers and machining. I think if you took a ‘greenhorn’ and stuck him on a CNC you’d have trouble. You have to have a pretty good understanding of machining. I think the best guys are the ones who learned on conventional machines and may have even struggled with them for a while but understand the hard part of it now.”
McCreery says that Nyes is the only shop around his part of Indiana that can do all of the things they do. “There’s a lot more we can do now with the CNC machines, and we can bring it all in-house and have more control over the quality of the product. We take a lot of brand new blocks and do several different machining steps on them. A DT466 is about the biggest engine we can do in any of our equipment. We also do a lot of Cummins blocks, the extreme side of the B-series engines and a lot of big block Chevy stuff. We’re also doing our own heads now.”
MRE’s Mullins says there’s a need to organize your shop a little differently to get the most out of a CNC. “We’ve totally restructured what we do. Now we bring in a pallet load of blocks and machine blocks for about a week. Then we shelf and stock those. Then we bring in a pallet load of manifolds and cut manifolds for about 3-4 days and shelve those. Then we bring in a pallet of aluminum cylinder heads and and then a pallet load of steel heads, and then a few Ford heads because we don’t sell as many of them. So it’s just a cycle.”
After owning his CNC machine for a year, Mullins says it is finally starting to pay off. “We’re now getting to the point where it is just a cycle for us and we’re just popping parts in and cutting them. I’ve got a pretty strong business, so it hasn’t really crunched us money-wise, but now we’re seeing where we will be making some money off of it. It’s been hard work getting here, though.”
Ron Hutter of Hutter Racing Engines says he used to have a Sunnen CV-616 hone, which is a standard workhorse cylinder hone, but he decided to replace it with an SV-10 that is CNC controlled. “It allows me a whole lot more flexibility. I can do a lot of things I couldn’t do with the 616. It’ll map the cylinder profile as I’m going, but more than anything it allows me to tailor the crosshatch where I want it rather than being at the mercy of the pulley ratios. And it has the power to tote the diamond honing stone a lot better than the 616 did. It allows infinite stroke speed and rotational speed of the honing head. Just all around it’s a lot more flexible for what we do.”
Hutter says that he bought his first CNC machine about 15 years ago, and has never regretted it. “We have some other CNC machines so the SV-10 wasn’t hard for us to learn. We have a 3-axis and 2-axis mill. I don’t know if it’s any faster than anything else, but the job that you get is much better. You can do what you want with it, if you know what you want.”
Nyes’ McCreery says that his Rottler F68 has been especially easy to use. “All the programs we need are set up so we can run a big block Chevy, pull it out and put a small block Chevy in, then pull that one out and put a Cummins in. The programs are easy to use and allow quick turnaround when changing over to another unit.
McCreery says the F68 is pretty much plug and play. “With the block boring software you give it bore space dimensions and where you want to start and where you want to end, there’s prompts for everything it needs. On the cylinder heads side it can be a little more complicated, but it’s a lot easier than an industrial CNC for general machining. The head porting machine will also digitize heads so you can make your own programs. For the most part it spits out what it copies. It has definitely lived up to what we expected it to do.”
Rosa says that when he started looking into buying his Millport Red Rhino he already knew he couldn’t grow his business any further porting Harley heads by hand. “When I found out about the CNC I knew we had reached our limits doing the heads by hand. I’m in New York and our shop is less than 5,000 sq.ft. We pay $20,000 a year in property taxes, so to grow any further, we were maxed out doing hand porting. What’s the alternative? More labor? You still can’t ensure you’ll get the same thing every time and you’re at the mercy of a good day and bad day. The room that we port in really only allows a one-man operation, so this machine was an easy choice. There’s a lot of competition in the cylinder head business these days and every bit helps.”
MRE’s Mullins cautions that buying a CNC is not like adding another machine, however. “When you buy a CNC machine, you’re not just buying a machine – in my opinion, you’re buying a business. It’s one of the most difficult things that we’ve done as a company. You have to learn as you go. And you’re not just learning about a CNC machine, like when you’re lightening a block, for example, you’re trying to figure out where to take the right amount of material from, and that doesn’t really have anything to do with a CNC machine.”
Whether you’re buying a multi-purpose machine center, a hone or a specialty head porting machine that is CNC, be aware that profits are out there, but perhaps not instantaneous. As HRE’s Hutter so aptly points out: “There’s a learning curve with everything.”
