making custom rims

[rayray]

i need to know if a cnc machine could be used to make custom rims for a car at least up to 26'' and how much it would cost

[plexer]

Of course they can how do you think custom rims are machined, as for the cost sorry can't help you there. Or did you also mean does someone here have the machine?

Ben

[cbass]

To be able to machine at least 26" in both x and y axis requires a HUGE machine. Muchos denaros.

Carlo

[CNC Pro]

I’m assuming your is question is for automotive wheels? If so, are tire manufacturers producing tires for 26” rims?
As far as machining the rims, I’ve seen rim blanks available that offer billet centers ready for custom machining. I’ve seen this type machined on machine centers or open bed mills where a ¼ or ½ of the rim is machined, then repositioned/rotated on a fixture. This process allows the large diameter to be run on smaller travel machines.

[Bluesman]

Well when I was working in field service for a Mori Seiki distributor here in MI we set up up quite a few lathes for the Howell wheel plant. They were for the most part ZL35 and 45's twin turrit machines. About 400 grand apice with no options as far as I can remember

Miss them days, BLUESMAN

[cbass]

Originally Posted by CNC Pro I’m assuming your is question is for automotive wheels? If so, are tire manufacturers producing tires for 26” rims? As far as machining the rims, I’ve seen rim blanks available that offer billet centers ready for custom machining. I’ve seen this type machined on machine centers or open bed mills where a ¼ or ½ of the rim is machined, then repositioned/rotated on a fixture. This process allows the large diameter to be run on smaller travel machines.

Is this what is refered to as "indexing"?

[CNC Pro]

For those of us that require the additional keyboard practice, it is as I described. For those of you more literate and nimble of finger than I, you could refer to it as “Indexing”

[AMCjeepCJ]

I build custom motorcycle wheels, my newest machine cuts up to 22 inches in Y (which means you can EASILY cut a 26inch rim, remember you don't need travel for the whole O.D. ESPECIALLY on cars but you do need clearance for the machines castings,) my machine ran me about $80,000 or roughly $1,500 a month... It's a LOT of fun!!

(To explain the required cutting travel, calculate it this way... Lets say you are cutting a 26" rim, you don't cut clear to the O.D. but more realistically you'll start your cut approx. 2.500" in from the outer edge... Multiply this by two (2.5x2=5.000") and you get the overall amount to deduct from your O.D. wheel size, (26-5=21.000") Ok, so 22 inches of Y travel will cut everything you need and give you an inch of play to bolt down the blank... That leaves only clearance issues... To see if the machine you'd then be considering would suffice, take the original O.D. and divide by two, (26/2=13.000") and add half your "Y" travel, (22/2=11.000") So in this case (11"+13"=24" don't ask, just trust me it's not worth explaining). Now with your machine at its ABSOLUTE POSITIVE "Y" position, (slightly in from the stop, say 1/4", you can get around this step but if you aren't sure, just do it and save yourself $80,000 it will give a visual of what the calculations mean). Check to see if you have slightly more than 24" inches of clearance from the center of your spindle to the casting / ways / bearings / shields, etc. and you'll know if you can hold the wheel in without damaging your machine, wheel or tooling... You'll still need to check for casting clearance on the head verses depth of cut to see if you'll kiss the lip of your wheel with stationary machine components but that is where experience comes into play with tool overhangs, feeds, speeds and luck...) I know that Fadals are very careful about having no extra wasted space, this is bad when it comes to wheels, many other machines share this design mentality, good for shop space but bad for your application... You'll need a top quality machine to realistically pull off cutting wheels using 'dead space' without going to a true 26" travel machine... (which will cost a MINIMUM of $25,000 MORE for travel you will NEVER use!! oh, 28's, I forgot, lol~ )

You can index if you want but only rarely will it even work in a machining center, you have shrouds to contend with and given the RPM's and gumminess if aluminum, you will NOT want to go with something you can't use high pressure flood cooling on...

Indexing is a nice thought but not practical for any kind of production in wheels because of the shroud problems on machining centers and the lack of cooling / chip evacuation required in an open bed mill.

It would work if you were building wheels once or twice a year on a normal bed mill or 'tool room' mill for that matter. Just don't kid yourself with any thoughts of high productivity / making a profit and make sure you have your ducks in a row on how to machine accurately on what most likely would be a less rigid piece of equipment, (although not always the case by any means) We won't even get into fixturing concerns to properly reorient and reindicate the part after rotating... In short, don't even consider it!! It's VERY possible but not a viable option in your specific application, it's only good in theory~

You can definitely pay more for a faster machine than I have but mine cuts up to 600ipm with 1000imp rapid at 24 peak horsepower / 15 continuous... Hope that helps... Oh yeah, you'll still need some good software to run everything and that will go from $1,500-$20,000... Don't forget your 'basic' tooling is going to cost another $2,000-$10,000... Lastly, you're going to need a small shop full of secondary equipment to do a good job... Sorry the prices are so spread out but you sound really new to the industry so you're going to need more expensive software due to inexperience, lol, don't take offense to that comment, I just mean you'll need good software to make up for notta lotta machine time...

Good luck with it, just remember insurance on your parts is enough to bancrupt most folks~ PLEASE-PLEASE-PLEASE, one thing to think about before jumping in with tons of cash, wheels aren't a cosmetic part of a vehicle, if you engineer one wrong, YOU WILL KILL SOMEONE, sooner or later... If you have the skills its a LOT of fun but just remember that EVERY SINGLE WHEEL you sell, could cost you everything you'll ever earn for life if you get sued... Just a thought~

Another thing you might want to keep in mind is that I'm a OEM for two motorcycle companies but I have another customer in a different line of business just for that machine during slow periods, banks want their money whether you're getting paid or not...

If you get into this and are serious, I'd love to meet you at an upcoming show sometime and 'talk shop.' Have fun, just realize this is an ULTRA competitive market as of late, so have some sales under your belt by subbing out BEFORE you invest in equipment, try to tackle one hurdle at a time, designs are the easiest part by far!!

PS,
I'm all for competition, in manufacturing especially... It's nice to see fresh designs and new ideas coming to market, lol, the first piece I did ended up at Rowe Machine and the owner is still trying to find out who built it, now thats a compliment!! We're going to the dealer show in Cinci to show off our radically new designs on February 4th-6th and shake things up a bit more before introducing myself in person to those guys, instead of just emails and rumors... In our case, instead of redesigning the wheels basic shape, we redesigned all of the components that make up the wheel, (remember there are four basic parts, now ours has three visible, sounds simple but took crazy engineering time~) Anyhow good luck in your pursuits and I hope to meet you someday... God Bless!!

Phil 4:13

[anchornm]

If you are trying to do it "on the cheap", you may consider building your own mill with a head that can be horizontal or vertical. (figure $10,000) Look on ebay for a huge rotary table for a 4th axis. (figure another $2,000) Use the rotary table as a "muther huge" lathe. Dish it out and cut the spokes from the top. When you need to work on the "bead" surface, rotate the head and attack it from the side. With tools and software, I can't imagine carving a wheel for any less than $20,000 The main problem I see is finding a 26" hunk of billet Aluminum or Magnesium! I can't imaging the technology required to make a rough casting or forging. Remember, if your vehicle requires a 26" wheel (I am thinking Escalade or Hummer) it will weigh multiple tons. No disrespect intended, but the people that would operate this type of vehicle may present additional variables!

[AMCjeepCJ]

You typically don't build wheels from the solid, you buy forgings out of Florida or Cali~

Something worth mentioning are machine times that would probably blow your mind cutting a billet piece that big. Remember when Jesse James on MM3 went the billet route?? Took him a whole week or something dumb like that, lol, sweet wheel but he's also got the bucks to cut stuff inefficiently. Anyone ever seen a rotary Haas mill like he has?! I don't understand the advantages, seems like you'd only need an XY and rotary axis, how would you cut an straight line without using the rotary?! Anyone who really knows about these things please respond, lol, that thing baffles me unless it still has a full XYZ and rotary...

If you try cutting a SOLID piece of aluminum that big, it's going to create enormous problems with stresses being relieved and the part warping like crazy!! I'm also curious how your going to make a homebuilt heavy enough (read: rigidity issues) to handle the forces involved in starting and stopping a piece that big, let alone take up vibrations or be able to take any depth of cut or speeds fast enough to make a profit. That in and of itself would mean you're going to need a big mill to start with just to build your big mill!! And if your against buying the big mill to build your big mill, expect HUGE bucks to hire it done, just to have pay out the rear for EC's several times to tweak it since you can't use your own big mill in your own shop, you get the point... Kind of a catch 22 if you ask me~

Another thing, were you thinking of using the rotary table as a lathe spindle?? Just curious, I'm thinking it wouldn't work for very long, could be wrong though. I experimented before with using an inexpensive rotary table on a grinder and it generated soooo much heat, lol, that you couldn't hold a .002" tolerance after prolonged use without special cooling, they just aren't built for the continuous rpm's, (granted rpm's would be low considering the very fast surface speed at 26" diameters). I ended up buying a WWII surplus grinder and I can hold .0005" all day long on a flat 30" diameter part, it's absolutely amazing how fast it grinds too!! An example would be my 12" flat disks, my cousins have two of the biggest grinders in Kalamazoo and it took 35-45 minutes per side to grind in, my 'antique' does BOTH sides including flipping in as little as five minutes TOTAL if I'm in a hurry!! The old stuff rocks in certain cases but for making a wheel, AT LEAST start with a HUGE old mill and retrofit before you go building something from scratch, ugh!!

How would you get the backlash out of the rotary table?? I guess you just want to use it for a spindle and then lock the gibbs or whatever it uses for locks to then use it as a mill table?? I'm a little confused how this could work, but if you built one, lol and it works, I'll buy one!! Have you ever built a custom machine?? There is a lot more involved than just theory. Kinda like the first time you go from math in school (perfect numbers) to real world mathematics (tolerances) there is quite a difference. (Just curious, I mean absolutely no disrespect...) I'm just trying to recommend things that work on the first try, second try, 157th try and I've done first hand. That and honestly I was bored at my shop when I wrote the other post, lol, ever get in that rut??

I almost forgot to ask why you need a tilting head?! You obviously know an uninterupted cut like you get with a lathe is the best way to remove stock, so were you recommending this guy use a mill to cut the outside and beads?? Good luck getting everything smooth enough to hold air!! Although it can be done easy enough that way but not nearly as fast... Much confusion going on here in Kazoo as to the advantages of this design?? Why wouldn't you just use the side of the milling head to mount tool holders there, you've got the Z axis in place especially if you were really just using it as a lathe to rough stock out to begin with?? You could still use it to mill in your spokes and it would be more rigid. I did like your comment on dishing the centers out, THAT is a very good idea it would save tons of time, I just think focus was lost when it came to the tilting head, if we're really just making wheels, it's a pointless add on.

One last thought, all in one machine are for basements and garages generally speaking, not usually industrial applications! That said, I really want a lathe with live tooling, lol!!

[anchornm]

Please look at Ebay item #7572595403 It is not a toy, and certainly up to the challenge -- right now it is at $2500. Are you telling me that you could not find a way to hold a forging on this table and a way to reliably lower a spindle into that forging using another $10 grand? I am in the process of building a simple 18 by 24 gantry mill and am quite aware of the stresses. Any day of the week you can buy Thomson 1 1/2" rails with carriages that can withstand 1 million inches of repitition while carrying over 1000 Lbs. -- The spindle required shouldn't need to be driven with more than 2 horsepower. A 2 horse head and all the running gear should weigh under 200#. -- Mind you the rails that are supporting that spindle are capable of carrying a 350 Chevy engine and you (if you weigh less than 300 lbs) for a million cycles. As for accuracy, why on earth would you need accuracy of 1/2 of one hundred thousanth of an inch? In my vision of reality, a properly torqued lug nut could easily deform all but the most rigid aircraft aluminum by as much as 15 thousanths of an inch. You couldn't even mount the wheel without clearances of 10 times that! That is no excuse for sloppy machining, but the point is that IF a person was to build a reasonable structure to drive a surplus ER spindle and 3/8" roughing tool and lower it into a piece of work (billet or forging) that was being rotated by the above table, how could you NOT be within a few hundreths of an inch. Allow up to 4 hours for cooling breaks. A few finishing passes with a 1/4" ball end mill and you are done. OK - the lug nut seats may need a pass with a 1/4" end mill. I believe that my original alegation requested $20,000 for parts, tools, and software -- Heck, even throw in a few thousand for fabrication of parts at a top-notch job shop -- I still see that as totally reasonable. If the original poster needs to "Crank out" 8 wheels a day, then he/she would need to build a dedicated device, but that is a different story. Lets assume that someone had a job load that would require that they crank out 8, $2000 rims in a day -- they could suffer through the first week and then hire an engineer to work out the details (at $3000 a week). Lets get real -- How many people are standing in line for such an item? If a person couldn't "finish" such a wheel at a profit, then he/she should look for work elsewhere.

[AMCjeepCJ]

I think you somehow thought I was attacking you personally, no disrespect was originally intended but you didn't address any of the things I brought up, why not?? The rotary table you specified from ebay is a manual model albeit a VERY nice one. I see no where on the site where this item was built for continuous use as a spindle, (my whole point,) and you still mentioned nothing of backlash, (note the handles to lock the ebay items table in place). I'll point out AGAIN these things are not meant to be used as a spindle, they are made to rotate heavy parts accurately and NOT vibrate much. Clamping the silly forging down is super simple, everyone knows that! Maybe you meant he should mill the outside instead of turning it, (hence lower rotational speeds,) but I automatically assumed you were smarter (had more experience) than implying he should try that.

I don't like being a jerk but you said a few hundredths of an inch being close enough. How in the world do you expect to blend different tools together if you aren't holding about .001" at least?! The key difference between a precision machinist who's livelihood depends on quality and your typical hobbyist is we don't even think of using hundreths as a tolerance unless your building a deck

I had a good laugh about you building a gantry mill and yet you talking about spindle requirements, tolerances, etc. for a mill requiring 20"+ of travel. Even the smallest knee mills have about 2hp. And they're a TON more rigid than your gantry and did I mention incredibly easy to stall out?? Gantry's are wonderful machines but your on a thread with an "industrial" question, so please try to refrain from giving him a "hobby / wood working" answer, wheels are 'meh-tal'. Oh wait, BFG just came out with rubber ones, me bad, lol

You can't machine a wheel on a home made gantry mill, its not rigid enough to have realistic cycle times. (Yes you theoretically could do it, everyone knows you could skim pass the entire wheel including roughing, just don't expect much out of 2hp.) You must be a master at blending out everything with a ball cutter.

I'm at a loss for words to think the 'big guys' like Haas, Mori Seiki, Fadal, Mazak, Milltronics, Hurco, ___etc.___ haven't caught on to the fact that they should be making equipment lighter not HEAVIER!! I was a fool to buy a 16,000# mill instead of building me one in the old mold shop.

When you are talking of machining tolerances you obviously know very little about it first hand or at least aren't applying much if any of your knowledge. However, as far as torquing down the lug nuts and deforming the wheels, you're on the right path but exaggerating the real world deformation. If the back side is flat and you have two machined mating surfaces bolting together, I bet you don't get .001" deformation on a properly made custom wheel, (castings on the other hand, who knows but I bet they're really close if the backside is turned or milled flat.) This is less than the tolerance the wheel was made with so it's really a moot point. I'm willing to build a jig to test this, I already built one for rotor deformation testing. It's right behind me.

Ironically it's incredibly easy to test, I'd just make a steel hub to bolt on a rotary turn table, shush!! Then slightly tighten each lug, dial indicate the entire leading edge, writing all the dimensions on the wheel in felt tip, the properly torque and run the table around again. Presto!! If this becomes an issue, I'd love to make a large wager and video tape the results and post them... What do ya say, $2,000?? I say it's WAAAAAAAY closer than .015" and I wouldn't think it's over .002" and honestly I don't think it would move...

To give an example of this, are you saying that bolting two ground pieces of metal together will warp the plates?? C'mon, flat plates have very little structural rigidity compared to a wheel design and we know the plates won't warp if they were carefully ground in after the holes were drilled and tapped on the one plate and clearanced on the other...

You said:
(((( In my vision of reality, a properly torqued lug nut could easily deform all but the most rigid aircraft aluminum by as much as 15 thousanths of an inch. You couldn't even mount the wheel without clearances of 10 times that!))))

For starters, you sound like you know what your talking about for half a second then that pesky reality sets in again, are you talking 6061?? It can deform. 7075, it can too, hell anything can bend depending on the design, although some grades more than others. But as we've clearly seen, two flat plates aren't going to flex .015"~

Your problem is trying to guess how much deformation will occur when torquing down a wheel without understanding wheel design. I've only measured deformation of properly torqued rotors but that was less than .002" on a flat motorcycle rotor!! That's about the least rigid thing you can bolt down!! Were you assuming most custom wheels are made out of cheap materials?? It might be those wide open (.030" tolerances) you say are acceptable.

And I quote:
((((how could you NOT be within a few hundreths of an inch.))))

I'll let you hang yourself with that one. Now lets ponder the cheap materials scenario for a moment, the increase in cutting and polishing time would WAAAAY more than offset the extremely negligable savings in material costs. You still mentioned the "billet blanks" angle like this is a viable way to machine a wheel, yet you won't address the part warping while you cut it and relieve internal stresses. How much were leaving for a clean up pass?? I'm wondering if your lug nuts aren't torqued a little too tight, lol. I'm just a punk kid, lol and sarcastic by nature so realize I'm kidding, relax~

Your vision of reality is awfully cute but in the 'real world where we drive 'real vehicles' you'll notice you say you need .150" to mount a wheel. Are you insane?? Clearance for the center item may need that but you hold by the lugs, which are tapered to line up VERY precisely, maybe plus or minus .005" on a new wheel. (read: 1 / 15th your tolerance) The holes are then clearanced for the studs (at most .032" not .150") but you line up with the tapers that are on the lug nut, not the clearance hole. My wheels are within .001" to get everything to lock in properly with no slop or vibrations. I've NEVER in my life heard such blasphemy as a plus or minus .075" tolerance on a wheel!! You must drive a pimped out golf cart!! At 15mph I'm sure you wouldn't notice!!

I find it amusing I build wheels for a living yet even with four generations of experience teaching me how to machine quality components, you're giving me garbage without answering my questions, just answer how you're going to get rid of "rigidity issues," please?? While your at it, please explain how to get a rotary table to double as a spindle?! I honestly would love to able to use them for that but it doesn't work, sorry~ If you meant you were just going to mill the outside including the beads, well now that is idiotic to mill that instead of turning it (timewise.)

For your info, you responded to my talk of stresses, I was referring to a billet block being milled away!! Meaning your part will warp WHILE cutting, not good for blending out things but then again, 11 of my relatives build only plastic injection molds for a living, so what do I know?? Oh wait, I build those too, oops

What is your background in machining?? What I'm getting at is how much experience do you have in big mills, lathes, grinders, etc.?? I don't think you are being realistic with your ideas on using rotary tables, no that's being nice. You build your machine and have it hold .001", 8 hours a day and I will pay you $40,000 for it, instead of buying another CNC to free up my big mill. I do this day in, day out, 6 days a week and as much as I'd like to believe you can build such a machine for cheap and there are members on this site I believe could possibly pull off such a feat, it's not you or me, not with that design.

You also said:
((((Lets assume that someone had a job load that would require that they crank out 8, $2000 rims in a day -- they could suffer through the first week and then hire an engineer to work out the details (at $3000 a week).))))

Your absolutely right here and here is how he / she would do it. I figure that your machine would fetch $75 a ton locally so lets high ball and say you took a big load of chips (or scrap wheel blanks more likely) with you to the recycler too, you're starting 10-12 weeks behind and $19,925 in the hole and now you have to do it the right way and you're paying "your engineer", ($3,000 a week?! I'll work for you for $2,200 a week!! ) to spend a few hours lookin' on Ebay for a real mill... I just didn't see any point adding $20,000+ to what he needs to pay to build wheels, me bad!!

I noticed you've only posted twice, so welcome to the 'zone'. I was in no way trying to insult you in the first post or make any assumptions about your skills but lets think this through.

Ok, to be fair lets forget your design won't work (but only for a minute) for this application and think logically. If the original poster didn't know if you could cut a wheel on a CNC, why in the world would you try to steer that poor person into building a CNC?? That said, please explain the tilting head and all the questions I asked in the my previous post. I asked those questions seeking answers, not a argument. Maybe I mistook your 'tone' but I feel I insulted you inadvertently the first time. My sincere apologies~ If it was this comment:

"One last thought, all in one machine are for basements and garages generally speaking, not usually industrial applications! That said, I really want a lathe with live tooling, lol!!"

I was basically saying I want an all in one, only a good one.

One last thing, $2,000 rim?? You must be dreaming if you think you can stay in business making just high end wheels without making them efficiently and with high quality / repeatably. There are still your cost for blanks, shipping, chrome & or polish (including shipping both ways,) your physical building (heat, electric, etc.,) machinery upkeep, tooling, INSURANCES!! There isn't a ton of money in it without superb quality, (read: tight tolerances) and high production levels and that my friend takes a lot more than just good equipment...

You know, the more I think about it, whoever started this thread should use your advise, I don't need anymore competition anyway, might as well sink their ship in the harbor instead of fighting at sea!!

I'm kinda sorry I'm being a turd to you now but I like discussing things point by point (intelligently under normal circumstances.) Your talk of tolerances set me off, I gotta get back to work. I just don't want anybody to try to get into this business with the WRONG equipment, peoples lives are at stake, not just the peeps who buy wheels (literally if you build them wrong) but also the folks who sometimes sink their entire life savings into starting a business and mortage their home. If RayRay is seriously contemplating this, he needs honest answers not theoretical speculations!! I want to see people succeed, no matter what country, race or religion. I'm set so I try to give people honest advise that works everytime, not something I'd personally like to try if I had extra time to play. Sorry to rip your post apart but it needed to be done in this instance, I'm sure you are a wonderful guy, I just don't see any first hand experience written in your posts. (I added this in after writing the next one~)

((((How many people are standing in line for such an item? If a person couldn't "finish" such a wheel at a profit, then he/she should look for work elsewhere.))))

What a prophetic statement, most have to do just that for the very reason you mentioned, it looks like easy money, lol whatever!! Big prices rarely exist long for no reason because someone will make it better / faster / cheaper tomorrow... Unless maybe you have brand recognition but that's a completely different ball game...