Wile7 Posted January 1, 2007 Share Posted January 1, 2007 Before the onslaught starts, I have searched back through archives since time began and found this article particualry interesting here I have a 'heated towel rail' roll bar on my seven. AFAIK it was fitted from new. I want to 'upgrade' to an FIA bar (and a couple of other upgrades costs permitting) so when I return to the UK later this year I can start to hopefully join in some circuit days/events etc. I want it 'chrome' because I am a tart. Peter Carmichael raised the issue of Chroming being a 'no-no' due to the structural integrity of the bar being compromised during the treatment process. I am trying to find out more. Does the 'Nickel' plating cause the same issue? I have had students work Chromium plated before in schools but admit nothing like a 'life saving' device such as a roll bar. What is the issue exactly? From my research 99.9% of cages/roll bars on big Yank 4x4's seem to be chromed and fitted from new. Many classic car 'impact' components such as bumpers and wire wheels, classic bike bits and so on are chromed. Many sevens have 'chromed/nickel plated' suspension parts etc. and many accesories too. I am not saying Peter is incorrect, and as someone with a bit of 'technology' nouse I appreciate the issues of material contamination via inappropriate surface finish or application; any foreign substance can affect the impact resistance of materials (much akin to applying decals to helmets where the adhesives can often upset the impact resistance of the composite surface). I could get a Stainless FIA bar knocked up (and polish it ), or indeed paint a chrome finish - but I really want to know what the issues are. Whilst I 'google' and read up from my own books a bit more, does anyone out there have any conclusive proof one way or t'other on this issue please? Apologies for the length of this post Dave Dave Ardley. White Xflow with Clams Don't point that beard at me, it might go off. Groucho Marx Updated photos here Edited by - Wile7 on 1 Jan 2007 12:05:19 Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 Nickel plating uses an acid bath. My wishbones have survived with no known issues. Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 Incidently, the bling wishbones may become available later this year Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
Tony C Posted January 1, 2007 Share Posted January 1, 2007 High strength steel parts on aircraft (Shock struts and hydraulic rams) are routinely chromium plated - can't think of any obvious reasons why you shouldn't chrome a roll bar. Maybe PC knows why BRG Brooklands SV 😬 It seems that perfection is achieved not when there is nothing more to add, but when there is nothing more to take away. (Antoine de Saint-Exupery) Link to comment Share on other sites More sharing options...
Bozz Posted January 1, 2007 Share Posted January 1, 2007 We use electroless (or chemical) nickel plating for corrosion protection in pretty harsh environments including salt water. One of the advantages over electroplating is it gives an even thickness all over including at the edges and corners. Black or 'dirty' nickel is also possible. Bozz McLaren Orange and Black 1.6SS 6 Speed here Edited by - Bozz on 1 Jan 2007 15:05:13 Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 You will find people are moving away from chrome now, and using material known bt the name of the application process, HVOF (High Velocity Oxy-Fuel) where Tungsten Carbide/chromium nickel is sprayed on. Chrome VI is on many material "black" lists. See here for the process and here for the material. Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
Mickrick Posted January 1, 2007 Share Posted January 1, 2007 Electro plating is an electro/chemical proccess. To affect the structure of the steel, it would have to be heat treated. Chrome plating is not a heat treatment. It also will not affect the welds. Welds are often tested by polishing and acid etching. I would have to dissagree with Peter on this one. Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 The Nickel plating process will also show up any porousity of the welds, as the acid will leak back out, staining the nickel. Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
Bricol Posted January 1, 2007 Share Posted January 1, 2007 In a word or two "hydrogen embrittlement" - an unavoidable part of the chroming process with steel. I've nicked the following from A.N.Other as it seemed to explain it better than I could. "Hydrogen embrittlement is a brittleness of metal and chrome layer structures, resulting from the occlusion of hydrogen or condition of low ductility, which itself results from hydrogen absorption and the internal pressure developed subsequently. Basically, the hydrogen is interfering with the metal's ductility, which in turn makes the chrome build-up weaker and greatly increases the chances of breaks or cracks in the chromed area." And in a roll-bar, the last thing you want is a loss of ductility - ie it breaks on impact leaving you unprotected, rather than deforming plastically, absorbing energy and continuing to protect you. It's possible to reduce the effects by heat treatment - leaving the chromed item in an oven for specified lengths of time as specific temperatures to stress relieve the item, allowing the hydrogen to escape - this has to be done ASAP after the chroming process. Flash chroming may be a better idea as the chrome layer is thinner - but as it's a safety part, I think I might just stick with powder coating or silver paint! Bri Link to comment Share on other sites More sharing options...
Mickrick Posted January 1, 2007 Share Posted January 1, 2007 Hydrogen embrittement is commonly a problem with high strength steels, I doubt your rollbar is anything but mild steel. It's usually found in welds where damp electrodes have been used. I would have no problem chroming a rollbar (If I was a Tart 😳 😬) I worked in Dimensional Inspection and Quality Control for Caterpillar for many years, and a lot of components, including fasteners, were plated for corrossion protection. The earth moving buisiness is a tough enviroment, I don't recall any problems with failures due to the plating process. As bricol says, you can aneal or normalise steel by heating and cooling. They're both similar except the cooling times. But that's just my opinion, I'm sure I'll stand corrected p.s. has anyone ever used a rollbar on a Seven 🤔 Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 More on hydrogen embrittlement: Hydrogen Embrittlement This is a type of deterioration which can be linked to corrosion and corrosion-control processes. It involves the ingress of hydrogen into a component, an event that can seriously reduce the ductility and load-bearing capacity, cause cracking and catastrophic brittle failures at stresses below the yield stress of susceptible materials. Hydrogen embrittlement occurs in a number of forms but the common features are an applied tensile stress and hydrogen dissolved in the metal. Examples of hydrogen embrittlement are cracking of weldments or hardened steels when exposed to conditions which inject hydrogen into the component. Presently this phenomenon is not completely understood and hydrogen embrittlement detection, in particular, seems to be one of the most difficult aspects of the problem. Hydrogen embrittlement does not affect all metallic materials equally. The most vulnerable are high-strength steels, titanium alloys and aluminum alloys. Sources of Hydrogen Sources of hydrogen causing embrittlement have been encountered in the making of steel, in processing parts, in welding, in storage or containment of hydrogen gas, and related to hydrogen as a contaminant in the environment that is often a by-product of general corrosion. It is the latter that concerns the nuclear industry. Hydrogen may be produced by corrosion reactions such as rusting, cathodic protection, and electroplating. Hydrogen may also be added to reactor coolant to remove oxygen from reactor coolant systems. Hydrogen entry, the obvious pre-requisite of embrittlement, can be facilitated in a number of ways summarized below: (Defence Standard 03-30, October 2000) by some manufacturing operations such as welding, electroplating, phosphating and pickling; if a material subject to such operations is susceptible to hydrogen embrittlement then a final, baking heat treatment to expel any hydrogen is employed as a by-product of a corrosion reaction such as in circumstances when the hydrogen production reaction (Equation 2) acts as the cathodic reaction since some of the hydrogen produced may enter the metal in atomic form rather than be all evolved as a gas into the surrounding environment. In this situation, cracking failures can often be thought of as a type of stress corrosion cracking. If the presence of hydrogen sulfide causes entry of hydrogen into the component, the cracking phenomenon is often termed “sulphide stress cracking (SSC)” the use of cathodic protection for corrosion protection if the process is not properly controlled. So you had better glue your roll bar togehter, rather than weld it Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
Mickrick Posted January 1, 2007 Share Posted January 1, 2007 How many Moto X bikes have you seen with Nickel plated frames? I've seen Seven Chassis nickel plated. Front suspension whisbones. Like I said, I really wouldn't worry about it. Link to comment Share on other sites More sharing options...
Mickrick Posted January 1, 2007 Share Posted January 1, 2007 Chomp....chomp.. chomp...Slurp.......... Link to comment Share on other sites More sharing options...
CageyH Posted January 1, 2007 Share Posted January 1, 2007 I have two sets of Nickel plated wishbones Only dead fish go with the flow.... Link to comment Share on other sites More sharing options...
Unclefester Posted January 1, 2007 Share Posted January 1, 2007 Any decent chrome electroplate has to be a 3 step process anyway....first the metal is highly polished, then it has to be well plated with copper, then nickel, and the chrome is the final step. The electroplating bath has acid and other very nasty chemicals in it..... Chrome, though 'hard', is very porous, and needs a non-porous substrate or it will fall off like dandruff at the first sign of damp. I wonder if PC was thinking about the problem of weld porosity and acid getting into the welds? One thing I would check, Dave, is whether the FIA have any problem with chrome plated bars, as they are very fussy....You wouldn't want to find some scrutineer not allowing you on track because the bar has been blinged up I think you'll find it's not worth the effort making up your own bar, the cost would be more than buying one from CC....I know as I researched it myself. It's a very special steel which they specify, thinwall 45mm diameter and it isn't mild steel, it's a springy type with high carbon content, and cold-drawn seamless, not the mild construction quality which has a welded seam. A CC FIA bar for your car is about £200, with the Petty bar another £20. Check the FIA on plating.....probably best ring them as the Blue book isn't a fun read BTW for what it's worth I like the idea of a plated FIA bar so do let me know how it goes! 😬 Lucy in the Sky with Diamonds..ooooh hooo hooo!!... 😬 😬here *eek* Edited by - Unclefester on 2 Jan 2007 23:14:02 Link to comment Share on other sites More sharing options...
Unclefester Posted January 1, 2007 Share Posted January 1, 2007 Probably the best bet would be to ask Arch to make you a tripleplated bar....and to be extra careful with the welds. Ring Bruce and see what he says! Let us know!!! I'd be interested to hear what Peter C reckons is the problem.....maybe he just doesn't like tarty Sevens? I nearly bought a Proper S3 Lotus Seven Holbay in 1976, and it definitely had fully nickel plated front suspension. I think nickel plating is more 'respectable' in engineering circles for things like frames, suspension parts etc, though for the Tarty it has a slightly yellowish sheen to it, where chrome is a bluer, more perfect mirror reflective finish. Nickel is the more resistant to weathering, as it's less porous, so any chrome plate worth the name is based on a good thick nickel substrate which is itself on copper. The copper is the bonding layer, as it will properly lock onto a ferrous surface, then the nickel will bond onto the copper.The chrome is just there to look nice, usually! Lucy in the Sky with Diamonds..ooooh hooo hooo!!... 😬 😬here *eek* Edited by - Unclefester on 1 Jan 2007 21:44:00 Link to comment Share on other sites More sharing options...
Mickrick Posted January 2, 2007 Share Posted January 2, 2007 If the roll bar is high carbon content, then that's a different thing If you're going to do track days, then yes, check with FIA. Really the roll bar is only going to be as strong as what it's bolted to. If you don't want to risk it, there is a very good chrome efect paint., which a friend of mine had put on the rims of his 911, and you'd be very hard pressed to notice it is paint. But rather expensive, cost him €100 a rim I could take a run up to ask the painter which product it is, if you decide to go that route. Link to comment Share on other sites More sharing options...
Wile7 Posted January 2, 2007 Author Share Posted January 2, 2007 As ever - a fantastic and very useful response from everyone - Thank you *thumbup* This thread has confirmed many of my own thoughts. I will check about the use of Chrome on an FIA bar and the 'blue book' Nick I will post back when I have done the deed Dave Dave Ardley. White Xflow with Clams Don't point that beard at me, it might go off. Groucho Marx Updated photos here Link to comment Share on other sites More sharing options...
elie boone Posted January 2, 2007 Share Posted January 2, 2007 I tought but could be wrong that "chrome" roll bars where refused at trackday, competition Link to comment Share on other sites More sharing options...
caterhamnut Posted January 2, 2007 Share Posted January 2, 2007 Wile - I remember you asking this before - did I mention the 'chrome' paint you can get now, as used by our model makers - they have sprayed all the plastic body panels of their Smart Car so it looks like chrome. Not sure if this is a similar process to that used by Mclaren for their F1 car... Is it my bad memory or is there something to do with fire and chrome that makes it not as usable....? www.mycaterham.com here Videos here 98,000 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
CageyH Posted January 2, 2007 Share Posted January 2, 2007 If my car was on fire, I would not be worried about the roll bar being chrome! Would be interesting to hear what the MSA say about it. Only dead fish go with the flow.... Edited by - CageyH on 2 Jan 2007 17:18:41 Link to comment Share on other sites More sharing options...
Wile7 Posted January 3, 2007 Author Share Posted January 3, 2007 Still to find out Dave Ardley. White Xflow with Clams Don't point that beard at me, it might go off. Groucho Marx Updated photos here Link to comment Share on other sites More sharing options...
caterhamnut Posted January 3, 2007 Share Posted January 3, 2007 CageyH - I think it is more to do with fumes/by product, and others dealing with the fire? I might be completly wrong here, and totally making it up - but sure I read it on here somewhere!! www.mycaterham.com here Videos here 98,000 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
Paul McKenzie Posted January 3, 2007 Share Posted January 3, 2007 Angus, Chromic acid, which is used in the plating process, is a very strong oxidising agent and so contaminated materials (rags etc) need to be kept away from flammables since, in the event of fire, the chromic acid will 'feed' the fire by liberating oxygen. Chromium itself (as in the plate) would have no such effect. Paul Edited by - Paul McKenzie on 3 Jan 2007 18:02:01 Link to comment Share on other sites More sharing options...
strongy Posted January 3, 2007 Share Posted January 3, 2007 I have got a large towel rail that I no longer need, complete with TRV, you could try and bend it into FIA shape if that helps *thumbup* Dry-sumped White Supersprint Link to comment Share on other sites More sharing options...
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