OzVMX Forum
Clubroom => Tech Talk => Topic started by: Gippslander on February 28, 2011, 12:52:44 am
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Can anyone recomend a reasonably priced heat treatment business in Melbourne that can "normalise" a chrome moly Husky frame -- 1973 CR250 -- preferably in the Eastern suburbs.
I am just about to put two frames together to get a nice straight 73 Husky CR250, have a good welder man -- works with TIG all day, including some chrome moly tube on aircraft for "home builders", says he has the "correct filler rods" which are the same as what GMC recomended in an old thread on welding frames, and he says that a 30 year old frame of unknown history should be "normalised" after welding by heat treatment (same as GMC recomended in the thread).
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Touch base with Geoff, he has a tame heat treater on his books. Somewhere in Melb too.
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Weld it with oxy and you don't have to worry about heat treating weld. Both moly and mild steel rods are certified OK for welding moly in aircraft.
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Yep - try GMC. He had mine treated by a local guy in Melbourne after some repair work.
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I'm used to anneal or normalize stuff after welding all the time. Never seen the need with a bike frame thou. CM tig rods are nothing that unusual you can buy CM normal welding rods called WIA , 312 is the type I buy great for welding onto broken bolts. If you feel you really need to do this I would almost go with an BBQ and few old wheat bags and make a oven over the frame using the bags or bury it warm , hot sand if you have enough. I would weld cast iron thingy's and wrap them in old wheat bags and that worked a treat.
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Gee Slakey, shes had that cough for a while......mind you be carefull she doesnt knock you out. ;D
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I thought it was sneeze more than cough :P
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One hell of chest cold.
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Or two of them ::)
I will wait and see if GMC chimes in -- do not want to ask if it's a "corporation secret"
The mention of welding cast iron takes me back to my apprentice mechanic days at Richmond Tech -- did the class on welding cast iron cylinder heads -- pre-heat and then gas weld with cast iron filler rods (like a rough stick of solder but cast iron) and then as slow as possible cool down
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I would almost go with an BBQ and few old wheat bags and make a oven over the frame using the bags or bury it warm , hot sand if you have enough. I would weld cast iron thingy's and wrap them in old wheat bags and that worked a treat.
Yeah, you could do that.
You could also throw it into a bonfire and let skyrockets off to celebrate the procedure.
But the idea of normalizing is to make the frame less brittle and that involves cooking the WHOLE frame with no hot or cold spots at a set temperature for a set time.
Any process that fails to do that properly is a waste of time.
And how much are you going to save?
I charge $110.00 to have it done. $10.00 of which is GST and I make a bit on top of costs to cover pickup and dropoffs.
So really how much are you going to save with a hit and miss procedure.
Welding Cro-mo will become brittle around the heat affected zone of the weld. Less so if using Mild steel rod, more so if using Cro-mo rods, and I agree with you mate Gippslander, I believe a 30 year old frame would benefit from this procedure, especially if it’s had repair work done.
BTW, I did my sheetmetal apprenticeship at Richmond Tech.
Oh, and where to take it, I use a company in Heidelberg that are painlessly easy to deal with but I believe there are some companies in the Dandenong area that may be closer for you. I think there used to be one in Bayswater too.
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4130 Aircraft structures are not required to be heat treated if oxy welded, using either mild or moly rods.
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Give VALUE HEAT TREATMENT in Bayswater a call they may be able to help, good people with a lot of experience in the industry.
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I would almost go with an BBQ and few old wheat bags and make a oven over the frame using the bags or bury it warm , hot sand if you have enough. I would weld cast iron thingy's and wrap them in old wheat bags and that worked a treat.
Yeah, you could do that.
You could also throw it into a bonfire and let skyrockets off to celebrate the procedure.
It dosent sound like you have used this meathod before?
Heat treating the frame will do nothing unless there is some stress that comes from the repair job the tiny benifit you would get from normalizing the heat affected zone would be minimal.
A 30 year frame might get some small benifit and for just $110.00 you can argue why not.
IMO I just buy a slab and some snags to go with the bonfire and skyrockets ;D
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It dosent sound like you have used this meathod before?
No. I prefer not to contamite my steaks ;D
Heat treating the frame will do nothing unless there is some stress that comes from the repair job the tiny benifit you would get from normalizing the heat affected zone would be minimal.
Having worked with 4130 for years I have seen first hand how it can be affected by heat.
I once made a shock gusset for something and I centre punched on a fold line instead of where the hole was meant to be ( I’ve since got glasses ::)).
So I just put a dob of weld on the centre punch mark and linished it flat.
However when I folded the piece it cracked on the fold line right where the weld was, the rest of the fold was okay.
I believe it also work hardens in much the same way as stainless.
It’s hard to change the bend in a tube once bent unlike mild steel.
All this is only relevant to 4130.
If the frame is just mild steel then there would be no benefit.
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Ji where are you?
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Ji where are you?
Yeah, come on Ji, we know you are watching.
This thread could easily go 15 or 20 more pages… come on you know you want to!!!!!
Share the love :D
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…used this meathod before?
Now was that a genuine typo… or a comment on Geoff BBQ technique?
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Have just called Value Heat Treatment in Bayswater -- can do for $200 -- and has an oven width of 92 cm so the Husky Frame at a tad under 70 cm will fit -- a bit more on my side of town but still $90 more than GMC
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Get the frame powerd coated and they will cook it along with paint. ;)
Whilst I have welded a fair bit of CM it's not my thing so CMC would know more than me. Most of the TIG work I have done was in power stations welding steam pipe.