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by the way, the parts are about 39 inches long, 9 inches tall.....
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For over a year now we have been doing these simple but heavy & awkward parts, around 100 per month, and personally one of the best money makers in the shop (since i quoted them-ha ha). Anyways, original quote was for 26 minutes each, so about 43 hours after setups for a 100 part run. After doing these and finding better ways to get them done faster, we are now at about 22 hours total, but most of that time is handling, parts changing, and checking while in the fixture. Only about 3.5 hours actual cnc cutting time, and approximately 5 hours of manual mill cutting time, so the rest really adds up fast. What used to hog up the Hurco for 4 days is now only 11 hours.
So anyways, the customer notified us this morning that the first 6 months of 2012 they are guaranteeing 500 parts per month if we can handle the workload. Due to their flame cut, the parts are never exact, so they have to be clamped with alot of pressure in 2 main points, which is killing the kurt vises as well as our shoulders..... Also, handling these awkward parts from loading & unloading the Hurco, as well as the manual mills, which require flipping & twisting the part for set screw drill/tap operations, takes another toll on the body. Another problem is that in our business, tying up the machine for more than a day can wreak havoc for our other customers.
Here are pics of how the current operations go.....
http://i488.photobucket.com/albums/r...n/IMG_1455.jpg
http://i488.photobucket.com/albums/r...n/IMG_1456.jpg
http://i488.photobucket.com/albums/r...n/IMG_1457.jpg
http://i488.photobucket.com/albums/r...n/IMG_1458.jpg
http://i488.photobucket.com/albums/r...n/IMG_1459.jpg
http://i488.photobucket.com/albums/r...n/IMG_1460.jpg
http://i488.photobucket.com/albums/r...n/IMG_1461.jpg
http://i488.photobucket.com/albums/r...n/IMG_1462.jpg
So..... I am needing help in planning the attack of the future workload.
I am thinking definately upgrading to hydraulic or pneumatic vises, and possibly more than one part in the machine per cycle. I have just browsed kurt's website, but I dont know of many others, besides parlec.
Also, i have started looking at used machines to handle this workload. One that has gotten my attention is a used Haas VF4 with auto pallet changer, and plenty large to handle these parts, and handle more than 1 per pallet. The pro's of this machine is that it has an automatic pallet changer (so gauging & loading/unloading is done outside the machine while the machine runs), has the same cat40 taper our other cnc mills have, has plenty of torque to handle the insert drills we have now and much bigger ones, and the cost of the machine alone is about equal to the profits from the 6 month run of parts. Granted we will still have to pay for transporation, installation, transformer, and other unknowns, but for the most part the guaranteed run will cover the majority of the expenses as well as give us an opportunity to expand our capabilities. Another PRO is that its powered up currently, so its not an unknown about its capabilities, we can fly out there and check it out before the purchase. The cons are the unknowns, like are we throwing money in the wrong direction to solve the workload issues & ergonomics issues. I do know that buying a pallet changer for our Hurco is going to run around the same prices as the used Haas machine with pallet changer included.
link to haas.....
VF-4 APC | CNC Vertical Machining Centers| KDCapital
I also am in contact with this company about spindle orientation & locking. I dont know much about the Haas machine centers, but I am guessing they (haas) will sell me pretty much any upgrade for that machine that they can if needed? The question about spindle orientation & locking might actually not be needed, since i am unsure on how angle head tooling works exactly..... However in my thinking, with an angle head and stop block, i could get them made for the spindle orientation position i need to the part placement, and that i can use a 9mm carbide stubby coolant thru drill instead of split point hss drills to shave time. This is for the set screw on each of the big holes in the part. They also need to be tapped (10x1.5mm), so I am unsure if a angle head like this can handle that operation? Also, can you rigid tap from the side using xy location as the depth and not the z? or would i want a spring loaded collet in the angle head? or maybe thread mill in the angle head (depth of the thread is about 7/8" to the hole)? Like i said, angle heads are greek to me currently, but not for long if this is the way to go. I know i can get by using xy feed command for the drill if need to be, but would also like to know if the g81 can be executed from the side like this....
Thanks for listening to my ramble, hope plenty of yall share your ideas and thoughts, im just a baby bird trying to get a worm, feed me
by the way, the parts are about 39 inches long, 9 inches tall.....
Love it!!!
Lemme ponder this for a little, I'll throw my 2 cents in... I love this kind of stuff, growin' up in a short-run production job shop..
Legal to post a pic of a finished part? If not, could you PM me one?
I've got some ideas but need to know about certain limits, for fixturing and process flow.
Depending on what else you've got going on with these parts, I would definitely gang 'em 3 or more up.
that pic is pretty much finished fizz. the hole on the right is 1.27" +.005 -0. the hole on the left is 1.585" +.005 -0. the part is about 39" long, and just under 9" on the Y, and 1.375" thick. the customer supplies the flame cut part, all we do is the 2 big holes, and a set screw in each one of the big holes. then the part is actually DONE, customer blasts them and powder coats them, presses a bronze bushing in the big holes, and assembles parts. due to the flame cut, i cannot base my xy stops on the right any more than a single wall, as well as y stop on the left vise, or the location of the hole will vary too much and not leave enough wall thickness for the hole to provide enough strength for the application. simple part, just heavy & awkward & large.
here you go fizz........ http://i488.photobucket.com/albums/r...CAfan/work.jpg
from those pink lines, you can see the placement of the set screw holes that will be done in manual mills after the big holes. they are mid-point in the side of the part, tapped in the direction of the line thru to the big hole.
also, on stacking them, keep in mind they are using 1045 plate steel when they flame cut these, so thickness is not always accurate to each other, and need not be, as well as taper on the sides from the flame cut make clamping a fun challenge. if any stacking was done, one would require that the spacing between be kept at a minimum, yet enough to pass the insert drill bottom slag, yet not too long as the boring head can only reach about 4 inches deep on the 1.585" hole. the other hole (1.27") is finished by a 1" carbide 4 flute endmill (till i can convince the boss to buy another boring kit), so untill then, stacking might not be a very plausible option as getting a longer endmill will invite deflection and possible tolerance issues.
i had a pm from a good friend on here that i wanted to share..... might help clear this up a little bit.....
his pm......
For most capital expenditures, you want to have a payback in 5 years or less.
the answer to that...
capital expendatures..... with our quote on 100 parts, at 43 hours, machine shop is 70 bucks an hour, one hour minimum, for a total of $3010 per 100 parts. that 70 per hour covers all overhead and costs, as well as a miniscule profit. but, at 3010 per 100 parts, we actually only have 22 hours invested now, so our cost (machine shop quote) is 1540, so 1470 is on top profit from that 3010, plus the miniscule profit of the 22 hour x $70 per hour normal profit. so with the 6 month guarantee of 500 per month, we are looking at 44,100 profit alone in 6 months, without figuring in the miniscule profit from actual machine time. that almost covers the machine cost. but we will still have other costs, like transportation, setup, electrician, new vises, and possible new cement foundation for the machine, which i estimate to be around another 30,000. so around 35,000 left in costs, the machine expenditure is over 50% paid for in the first 6 months alone, just being a dedicated machine for a week and a half per month. that leaves around 3 weeks left per month to schedule in more work with expanded opportunities.....
i dont know if i am missing anything here, but it almost seems like a win/win, especially since the profit is there in guarantee, and the only thing we have to do to make our current tooling work in the other machine is swap out pull-studs. same cat40 taper, same limitations, really only changing bed size and adding a pallet changer by adding the new machine, as well as expanding the operation.....
another pm from another great friend.......
his pm......
Oh, for a positionable right angle head, they don't work in a tool changer. You have to manually install and uninstall them for each part. I do not think you would gain anything by going that route. If you think you back hurts just handling parts, with the right angle head you would have to handle both the part and the head each time.
my reply.......
now as for the angle head questions.....
you said they dont fit in tool changers, however the machine i am looking at has a tool carosel, which you can space your tooling apart in case they are larger and tend to hog up room. with that being said, one would think the tool stop block be made in a position to not affect the carosel, since in a carosel operation it puts the tool back first, then rotates to the next tool, then picks it up, without a changer arm. let me know if i am missing something.....
something like this..... Compact Angle Heads for Smaller Machining Centers - BIG Kaiser seems like i could hold that in the carosel easily and adjust the position (1-360 degree rotation adjustable) to my likings..... hmmmmmm
yup, tool carosel not a problem.......
had a rep stop by today from deco, adn we talked about hydraulic swivel clamps that can be charged and discharged as to not have lines stay connected to the palet. and we looked at some NT Tools & Lyndex Tools for angle head drilling...... getting alot of great ideas floating around
My take...based on a limited knowledge of what you got, etc..
I'b be inclined to hold off on an additional CNC machine, UNLESS you've got other potential jobs it could facilitate. I'd also be hesitant to get into the angle heads, unless you've got other jobs they'd be very useful for.
What I was originally suggesting is nesting side-by-side the parts, 4 or 5 up, on a tooling plate. You could even go so far...if you've got a cherry picker that's handy... as to mount a tooling master plate on the table, then have 2 sub plates. Each sub plate has the locating and clamping for the parts, that way while the machine is running one plate's parts, your operator is loading the second plate, then burring the last batch. I think the Hurco's table is big enough for 4 up.
Instead of spending the money on the angle heads, which I'm guessing is around $2-3k each, and still having to load each part onto a special fixture ...
Dedicate a Bridgeport with a tool quick change, build a fixture that allows a part to be clamped on edge, quickly, with a relieved for the tapped hole pin for locating on the machine, and just do the tapped holes manually. What I envision is well within your 26min original quote... I'm seeing about 2-3 minutes for the drilling and tapping operation with the fixturing I've got in mind. (you'll have to bolt the Bridgeport to the floor....and kick the head around a bit)
I think, time wise, a dedicated $10/hr apprentice could build up some muscle running the drill and tap operation, because honestly, I don't see that much time gained, or profit realized, by screwing with angle heads on the CNC for that operation. Even on a horizontal CNC, you still have the indexing of a long part, loading time, etc... and a decent horizontal Haas will run you $100k on up.
This is one of those jobs that you could have for 6mo, then it could go away, so leveraging a debt based on this job is, to me, fairly risky.
With a Bridgeport, some clever fixturing, and a good low cost operator, you're still profitable, and flexible. If the job gets extended, then I'd consider expanding. But even at the 500pc increase, I think the only thing I'd do is optimize fixturing, and cutting efficiency. Loading and unloading, and handling because of the part's nature looks to me like the big bottleneck.
thats how we are doing these parts currently fizz, on the bridgeports. the hurco spits out the 2 big holes in under 2 minutes each part, so loading and hole verification is taking longer than cycle, especially because the flame cut makes each part hard to reclamp and get dead-nutz if the hole needs opened a thou, so we guage in the machine while still clamped. the handling time on the bridgeport end is killing us. actual cutting time from clamp to unclamp is 56 seconds for start drill/drill/tap, per hole. but handling, rotating, etc, makes it longer. plus the parts being 39 inches long, 48 pounds each, and awkward, does not make for a fun day doing 100, or trying to do 500. right now we have it down to 22 hours total for 100 parts, from quoted 43. in the hass, start to finish would be around 6-7 hours. no secondary, no ergonomics, no health risks, no handling time wasted. also, we would free up 2 bridgeports for customer emergencies, as well as the hurco, and atleast one machinist freed up.
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