Author |
Message |
Purpony
| Posted on Thursday, January 23, 2014 - 11:58 am: |
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anyone have any input on what the tuber steering stems are made of? what grade steel? any heat treating? thanks |
Alfau
| Posted on Saturday, January 25, 2014 - 05:46 am: |
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The very best Chineese steel. Your question is too vague to answer. |
General_ulysses
| Posted on Saturday, January 25, 2014 - 10:26 am: |
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I've often wondered this myself. Not just for "tubers" but for any motorcycle or even for mountain bikes (some of which have aluminum steering stems). I might guess a tough spring steel, but I doubt that's really necessary. Be interesting to hear from someone who might know. |
Jolly
| Posted on Saturday, January 25, 2014 - 10:32 am: |
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I'm actually more curious about the project he has going on.... |
Phelan
| Posted on Sunday, January 26, 2014 - 07:14 pm: |
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Considering he sold his XB forks but not his wheels, I'm guessing he's looking to put an tuber style stem in XB triples to fit later model forks. |
Oldog
| Posted on Monday, January 27, 2014 - 03:17 pm: |
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Pony I can only guess, as beefy as it is 1018 steel would probably work, 4140 crmo steel might work too I know some one to ask |
Purpony
| Posted on Monday, January 27, 2014 - 04:50 pm: |
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any info would be great. I talked to Cameron over at Roland Sands Design this morning and he said 4140 Chome-moly would be fine. They mostly use 17-4 stainless though. I was leaning towards the 4140. |
Jramsey
| Posted on Monday, January 27, 2014 - 05:13 pm: |
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My first choice would be 17-4,2nd 1144 stressproof,3rd 12L14 and 1020 last. 1020 would be plenty strong. Neighbor of mine has a soft tail Dyna with a 128 CI motor putting 150+ to the ground and had trouble bending rear axles every time he hammered it,after 2 oem replacements failed I made one from 17-4 and no problems after three years. |
Greg_cifu
| Posted on Monday, January 27, 2014 - 06:14 pm: |
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A good resource for picking out this kind of stuff, and even for buying what you need: McMaster Carr's steel bar selection guide. http://www.mcmaster.com/#standard-steel-rods/=qfs5 9f If you clock on the More link at the top of the listing, you'll get a table of all the material properties such as machinability, strength, etc. For instance: you already mentioned 4140 (4XXX series is always a good, tough material). If you look at the table, they have 41L40 which is a leaded version of the same alloy that is much better machining and has an even higher yield strength. Or you can compare to other similar materials. If this is being pressed into an aluminum triple clamp, I would stay away from anything stainless steel. The two do not like each other and will cause galvanic corrosion problems down the road. |
Jramsey
| Posted on Monday, January 27, 2014 - 08:13 pm: |
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The two do not like each other and will cause galvanic corrosion problems down the road. Too funny.
}} |
Greg_cifu
| Posted on Monday, January 27, 2014 - 09:24 pm: |
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Is there something funny about galvanic corrosion? |
Buell_bert
| Posted on Tuesday, January 28, 2014 - 12:44 am: |
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Should not be much different than bearings pressed in a aluminum wheel. Most galvanic corrosion is extreme in the marine industry (water/voltage differential) especially salt water. I know dissimilar metals will cause problems such as spark plugs in an aluminum head or steel bolts in aluminum but I use a never seize compound to combat this. |
Greg_cifu
| Posted on Tuesday, January 28, 2014 - 02:37 am: |
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Wheel bearings are not made of stainless steel. Steel against aluminum = about 0.2V difference in potential, generally ok Stainless against aluminum = 0.5-0.8V difference. Pretty significant. Look, if people want to ignore basic engineering principles, that's fine but, when somebody poses the question, it's going to get answered. Galvanic corrosion is very real when there is ANY water present. The stem is at the bottom of the steering neck so water will naturally run down and drain around the area. Any water that gets into that joint will not have the benefit of heat to drive it out (unlike engine or wheel bearing where heat is generated in normal usage). So water only has to get in there once. Once it seeps in there, it has no heat or other usage to cause it to flash to steam. The only way it will "dry out" is when all of its molecules have made sweet love to his lower triple clamp casting (aluminum loses in this tryst). He'll notice this when the steering stem starts going clunk-clunk, like loose head bearings but, it will be the whole lower bore of the triple clamp, blown out--or maybe the corrosion will start a stress crack and the bore will just quietly break out one day. Stainless is a bitch to machine (could spend $100 in cutters alone), threads tend to gall and the raw material is expensive. He already has a couple of very nice (and also probably overkill) high-alloy choices on the table. Somebody name one single attribute any stainless steel has that makes it a better choice for a steering stem than a non-stainless alloy. |
Jramsey
| Posted on Tuesday, January 28, 2014 - 09:40 am: |
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Stainless is a bitch to machine (could spend $100 in cutters alone), threads tend to gall and the raw material is expensive.} Standard HSS Drills put thousands if not millions of holes in 17-4 daily in machine shops around the world. It actually machines quite nice,just about any Carbide insert will whittle it to size and shape. Do you have any hands on experience using it? As far as galvanic corrosion,yea maybe in 2-300 years after the mild steel equivalent has rotted out. } |
S1owner
| Posted on Tuesday, January 28, 2014 - 11:38 am: |
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All the power companies talking xcel conexus nuke plants use aluminum with stainless hardware in exposed conditions and have for years not a concern. Stainless is the perfered metal if mixing ask how I know I have delt with this for 25 years My tuber stems are steel the xb stem I think is steel but I will check when I get home it is gold like a grade 8 bolt I too am curios on what the project is as you do excellent work! |
Greg_cifu
| Posted on Tuesday, January 28, 2014 - 01:23 pm: |
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quote:It actually machines quite nice,just about any Carbide insert will whittle it to size and shape. Do you have any hands on experience using it?
Yes, I do, and none of it was good. This is a sprocket I made out of 316. I broke two cutters trying to do the teeth faster than 100 SFM (solid carbide). I finally gave up and let it run at 100 SFM. After all the slotting and contouring, it was in the machine over 9 hours. It IS a tough son of a bitch though, and will probably outlive the bike it's on. I will freely admit that the only reason I went stainless was that I did not want to spend the money getting a 4130/4140 sprocket plated. Turning stainless was no different. In one case, I had to make eight pipe fittings, also out of 316. They were basically 2.5 NPT to JIS adapters. Big honking things with huge pipe threads. Again, trying to cut above 100 SFM (to get the job done). It just chipped and destroyed the inserts. In the end, I was going to have to call out a cutter guy and buy specialty stuff for this one job or just tough it out at 100 SFM. They were like 6 hours each in the lathe. Galvanic corrosion will not attack the stainless stem, it eats the aluminum. Fine, whatever, do what you think is best. Aerospace structure must behave completely differently than whatever stuff you work on because aluminum against stainless is forbidden without protective coatings or plating. In the end, it's got no advantages over 41L40 which will machine way easier and cost less. Nobody has a single reason why stainless should be used over normal, alloy steel, even with those disadvantages. The guy asked. All I did was share the McMaster link and bolster what Oldog and Purpony had already identified. |
Jramsey
| Posted on Tuesday, January 28, 2014 - 02:40 pm: |
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316 was never mentioned until your last post,different animal. You make it sound like the Aluminum gets eaten up from Galvanic corrosion like a cookie when soaked in milk. Vintage Hare Scrambles bike I built in '93. Three guesses as to what was used for the steering stem,swing arm pivot shaft and front axle.
20 years of abuse later its still going strong. |
Jayvee
| Posted on Tuesday, January 28, 2014 - 05:50 pm: |
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That is a pretty bike! Looks like Triumph, you know they had one very similar at the last Motorcycle show, new. Just not as pretty. I've found McMasters very informative over the last few years. But I did start out reasonably ignorant. Let me pose a non-hypthetical question? The Ti axle I got from Fireman Jim has the threading too short by 1/2". The other side has a built in nut on the end. Can a regular local Harley machine shop just continue the threading about half an inch, or does it need to be special tooling to thread Titanium? Can a regular lathe make 'rolled' threads, as opposed to 'cut'?? My Dad's a machines but has Alzheimers, he's about to turn 80. I used to call him with these kinda questions. |
General_ulysses
| Posted on Tuesday, January 28, 2014 - 06:04 pm: |
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Man that is a schweet Triumph! Stainless stem and all, SCWHEET MAN. Got any close ups of that 2-1 exhaust? I've been thinking about getting a Scrambler lately. It'd be cool to set it up like this one. |
Greg_cifu
| Posted on Tuesday, January 28, 2014 - 09:40 pm: |
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Very nice build you did there (really--I love stuff like that--I'm constantly on the lookout for old Rickmans because those types of bikes speak to me). As far as the rate of corrosion, I've seen it on my own vehicles. About 15 years ago, I discovered that the local hardware store carried the whole Hilman line. That included a great selection of stainless socket head cap screws. I used to replace damaged engine case fasteners and cooling system parts with those screws. Man, you could polish those things in a drill chuck and they would just sparkle. Unfortunately, on a bike that I took that much care in assembling, I also washed the bike frequently and it was put away after washing. That meant that water got into the small void around every screw shank and sat there until the next time the engine was truly run up to temperature for awhile (10-20 miles). Imagine my horror when I would go to remove one of those screws and the cavity was absolutely full of white powder--the converted remains of my aluminum cases and often the threads as well. I wish I had taken pictures because I can't find any good ones on the web. It was a lesson hard learned by me, even though I knew--intellectually--that galvanic corrosion exists. I don't ignore it anymore. I share that with people who might be doing something similar. None of us likes having to redo something that cost us time and money to create. |
Purpony
| Posted on Thursday, January 30, 2014 - 12:00 pm: |
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some have asked... this is what im working on- new triple clamps. These put the XB forks in the stock X1 locations and allow for handlebars! Still a work in progress. (Message edited by purpony on January 30, 2014) |
Gmaan03
| Posted on Thursday, January 30, 2014 - 03:13 pm: |
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Solid Works? Ever hear of Space Claim? |
Purpony
| Posted on Thursday, January 30, 2014 - 03:21 pm: |
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Yes, this is Solidworks... and Yes, I also have Space Claim as well has SolidCAM. (Message edited by purpony on January 30, 2014) |
Gmaan03
| Posted on Thursday, January 30, 2014 - 05:41 pm: |
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Cool, nice to see there are other manufacturing people here. |
Jayvee
| Posted on Thursday, January 30, 2014 - 05:55 pm: |
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I like the bolting places mass-centralized like that. Many custom makes like Twin, put the bolt clamping things in the outside front of the tube. Looks more traditional, but puts all those bolts farther away from the stem, and frame. there. Seems like the clamps, not the stem, are often made from aluminum. How about Magnesium for the Stem? Or Scandium ? |
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