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| Billet Rods https://slantsix.org/forum/viewtopic.php?t=25758 |
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| Author: | SlantSixDan [ Sun Nov 11, 2007 6:57 am ] |
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Quote: Quote: Stock 225" conrod length: 6.7"
actually I see no reference to one inch longerOne inch longer than that: 7.7" That is a really long rod to try to fit into an RG block!  
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| Author: | runvs_826 [ Sun Nov 11, 2007 11:44 am ] |
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Wow, gone for one evening and a whole bunch of stirring in the pot. Well, to start it off with the recent pop's looking into some old cnc from california on e-bay. He doesn't move real fast, and we're still trying to finish the efi in my slanter and the rack and pinion in his 49 gmc. However, I re-drew the rods to the 198 specs, and a total bottom end of 3.4in. However, I think for installation ease it will be better to install the rods in a bored motor over zero spec. I need to go through the design one more time because I had a lot of meat to handle the aluminum's density, however, because the majority want more of a stock steel 198 rod I'm going to find the volume x density of 4340 and find what my weight is because we still want a light rod. Last, I talked to a shop in hubbard, or who wants to charge me $60 an hour which I should use to cut out the first rod for sure to test and fit. Depending on what everyone wants I might use them to crank out a set or two depending on price. This will take some time so I will be popping in to see any suggestions, but when going with the other shop it will be just steel 198 rods, nothing to exotic. |
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| Author: | slantzilla [ Sun Nov 11, 2007 12:02 pm ] |
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Quote: Quote: I think Roger and I are thinking along similar lines, actually. Instead of custom pistons, we actually have an opportunity to pick some OEM pistons from an application that wouldn't have worked before, due to compression height or piston pin diameter. For example, how about the SRT turbo neon 2.4 pistons?
**********************************************************http://www.nolimitmotorsport.com/wiseco/apps-Dodge.html if not them, how about toyota and nissan engines with 88 mm bores? Greg Hmmmmm....I hadn't carried the thought process to this extent, but it's also a possibility. One can store the CNC program in a 'puter and rework it at will without an extreme amount of trial-and-error work to tweak it on a real piece of steel. So...what application is there that we can get a readily available, forged piston in about 3.40-3.48 bore? Roger 
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| Author: | Doctor Dodge [ Sun Nov 11, 2007 9:08 pm ] |
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Quote: Along that line also, you can probably open up piston selection a little more by varying the size of the pin hole in the rod too.
Having a thicker "small end" is a must. This is a major limitation area with a factory made SL6 con rod.DD |
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| Author: | runvs_826 [ Sun Nov 11, 2007 10:07 pm ] |
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expand if you can, any limitations that need to be fixed are good to know. i can't really find any pistons that are cheaper than the 2.2L to make the rods to work with, however, I'm not going to focus on that right now. Also, I switched to an H-beam design for the 198 rods |
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| Author: | argentina-slantsixer [ Mon Nov 12, 2007 2:55 am ] |
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Quote: expand if you can, any limitations that need to be fixed are good to know. i can't really find any pistons that are cheaper than the 2.2L to make the rods to work with, however, I'm not going to focus on that right now. Also, I switched to an H-beam design for the 198 rods
any images of the process? I'm drooling already 
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| Author: | runvs_826 [ Mon Nov 12, 2007 4:28 pm ] |
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well, this is the design with the h-beam design, I'm not quite sure if I'm satisfied with it. The length and width are correct, just trying to find a shop interested in the first 2 sets, they want to cut them but won't give me a price. 
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| Author: | Dart270 [ Tue Nov 13, 2007 7:54 am ] |
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Do you have a projected mass for these with bolts? Also, do the bolts thread directly into the body, or will there be nuts involved? Thanks, Lou |
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| Author: | runvs_826 [ Tue Nov 13, 2007 10:38 pm ] |
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For those still following this, so far the only news is bad news. The only shop that has talked to me about cutting rods and price wants and hour for set up, than an hour per rod. I wanted them to combine rods than seperated them. However, with their cuts so far it would run 7x$60 plus material. so overall the project is on hold untill we either get the equipment or I can find a shop that is reasonable. I will report back whenever something promising shows up. |
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| Author: | Dart270 [ Wed Nov 14, 2007 6:47 am ] |
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Now you are coming to the hard part. I suspect it will be hard to get below $500/set all told. That is still a good price if they hold up to abuse well. I would guess that your CAD program can calculate a volume and thus a mass of your rods? Thanks, Lou |
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| Author: | argentina-slantsixer [ Wed Nov 14, 2007 1:04 pm ] |
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I'm still interested if those are 4340 forged steel and can take some beating. Dimentions? can I install them thru the top deck? I say that around $500 is a very reasonable price for that kind of goods. |
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| Author: | MenkeMoose [ Wed Nov 14, 2007 7:45 pm ] |
| Post subject: | emachineshop.com |
Have you tried these guys- http://www.emachineshop.com? I read an article in the newspaper a while back that they were very reasonable... Moose |
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| Author: | gearhead [ Wed Nov 14, 2007 11:33 pm ] |
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As someone who has been very involved in design, machining, and manufacturing for a very long time, I think I should put some perspective on this thread. First off, $60.00/hr machine time is very reasonable these days for any kind of machine work. Just today I picked up a quote for a small brass part based on $120.00/hr on a Swiss type CNC turning center...although this quote was without any setup charges. Most shops charge $75.00/hr for time on machines that cost between $40-125K without tooling and have lease payments of between $1200-$2500/month not including all the other overhead of the shop. I charge $40/hr on my machines and I have virtually no overhead since my garage is mine and the machines paid for...alas, I don't have a large CNC mill though, just a tiny one. But I do run production on an automatic lathe, and work daily in a large production shop. Second: If the shop has a machine with any kind of time saving or machining enhancing devices...(rotary table, 5th axis, etc.) its going to be on the high side for costs, both machine cost and cost per/hr because of the added capability and specialty. Third: One hour setup time is extremely reasonable given the complexity of the machining operations you are expecting with this project. Changing from a parabolic design to an H-beam has added two more setups and at least one tool change operation to the rod, which also means having to setup and touch off one more tool during initial setup. Third and a half: Set up for the types of operations in this kind of project will typically consists of having to build some form of fixture to hold the part for machining. So you take a slab of aluminum or such and drill and thread a couple holes probably in the center to center points of the pin and journals, times 6 so you can machine six rods at one time. Most likely, you will also need to have some kind of shoulder so that the rod blanks can be indexed 180 degrees so that both sides will machine precisely. Keep in mind also that the operation to produce the rod blanks is complex as well... Fourth: Just to get to the point of having rod blanks, you must take an expensive slab of steel and cut the end off at the rod cap parting line, or two separate ones, that when combined add up to a slab width slightly larger than the total rod length, end to end. Precision machine each surface of the rod cap parting line, clamp the pieces together, fixture the entire slab vertical, then drill, counter sink, counter bore, and tap for connecting rod bolts times twelve for six rods. Now thread in the rod bolts, and cut through the slab five times to create six rod blanks. Don't forget to clean everything of chips between operations. Fifth: Now you have six rod blanks, with rod cap parting seams bolted together. Set up a fixture to drill and ream precision holes to locate the blanks on the milling fixture made in part "third and a half" of this diatribe. Sixth: Mount the rod blanks and mill the profile for one side Seventh: Clean milling area and reverse rods to mill the profile on the other side. Remove rods and prepare to create pin and rod bores. Eighth: Did I mention you now have to build a fixture or rig up a fixturing method to be able to bore the holes, because the rods were bolted down through the index holes previously created for the profiling operations. Now we must hold the rod some other way to be able to drill, bore, ream as needed. Ninth: Mount blanks or blank if one at a time, and create your bores. Then you did remember the bearing tang indexes didn't you...so unbolt the cap and rod, and fixture them so that you can create the tang slots. OK, maybe done now except for heat treating? Stress relief(shot peening). Then of course, you need to finalize your rods by resizing them on a Sunnen or equivalent rod honing machine. Keep in mind this description is for parabolic rods not H-beam, that would take two more operations. Oh yeah, are these rods bushed on the pin end? There are many ways to skin a cat...I typed this as fast as I could thinking on the fly...possible to save a couple steps, use different operations depending on machine capabilities or preference of machinist, certainly...but I think your quote was a steal, and I would jump on a few sets before they regain sanity. I don't mean this to burst anyones bubble, but without significant machining experience in a manufacturing setting, and a thorough understanding of the costs involved in operating a machine in a high overhead environment, or the costs of tooling those same machines, deciding whether something is "reasonable" in cost is stepping out of your field of expertise. It is easy to learn Solidworks, but difficult to gain the knowledge to understand manufacturability or time and cost based studies of production. Gearhead |
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| Author: | argentina-slantsixer [ Thu Nov 15, 2007 5:33 am ] |
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Quote:
....I don't mean this to burst anyones bubble, but without significant machining experience in a manufacturing setting, and a thorough understanding of the costs involved in operating a machine in a high overhead environment, or the costs of tooling those same machines, deciding whether something is "reasonable" in cost is stepping out of your field of expertise.
I'm 100% with you here. Might be the fact that I do machinework for a living too. I'd say that $500 a set is a bargain. I'd expect this kind of rods to be priced double that money ($1000 per set) wouldn't you? I mean, you sure typed fast and I can tell by the way you describe as how you'd face the job, you'e an "old timer" like me It is easy to learn Solidworks, but difficult to gain the knowledge to understand manufacturability or time and cost based studies of production. Gearhead  most CNC trainees would add at least 5 or 7 steps to your list... we had to learn to think for ourselves and then do the machining for ourselves....Still, it would be nice to see this happens @500 bux or ballpark per set. Maybe there's a reason why there ain't no big performance /6 aftermarket parts and that might be very well cheapness (don't mean it the wrong way but it's there... read the ex pipe or other threads) of the owners... I'm in if this can happen @500 ballpark. Would love to have the pin end brass bushed but that's something I can do myself once I get them rods. |
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| Author: | SlantSixDan [ Thu Nov 15, 2007 7:34 am ] |
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Quote: deciding whether something is "reasonable" in cost is stepping out of your field of expertise.
Yup...and a lot of people misuse "reasonable" as a synonym for "low" when talking about prices and costs...speaking of which, "price" and "cost" are not the same, and "significant" means real, not "large" or "extreme". Disappointment often results from using one of these terms when another is actually meant.
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