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I have a heat treating co. that will do some work for me on my AF frame. I am wondering if anyone knows what spec Service Honda uses for heat treating? Or the specific specs that Honda uses. I talked to the co. and they said maybe just stress relief would be sufficient. Thanks, Bob

I also talked with a heat treater, he recommended a retired metalurligist to call. he said he thinks stress reliefing would be suffient not knowing what metal the cast parts of the frame. also does anyone know what metal honda is using for the frame itself ?

to determine if need heat treating you need to know the metals your working with, until someone determines this your just pissing in the wind.

someone else has started a thread on this with metal testing on the frame, you should find that thread and follow it as info becomes available

Thank You, I will look and keep up with it on the other thread. I may have stress relieve done for now since the price is right

still after all these years ive only seen speculation as to what alloy is used and whether its treated or just stress relieved or neither. any metallurgist can test it and say with pretty much 100% accuracy the alloy then you can also get harness test to determine the temper. with all that info they could also determine whether it was treated post weld. doesnt cost much but i realize some people, such as myself, are on a limited budget and have other financial obligations. sooner or later i will get mine fully tested, unless someone beats me to the punch.

How about all the AF owners send a couple buccks to you and we get this resolved for good. I know our welders here are more qualified than those in the UK(recent cases as example) ha ha, but it would be good for many to know for sure what is the right thing to do.

at this very moment im not in a position to test mine. i recently sold my truck and my car isnt running good enough to make the 2 hour drive to have testing done. im working on getting better transportation but until then the testing will be on hold.

Maybe MXdogger might be interested since he know a retired metalurligist to work with?

The Y section was a 7XXX series on my 04 CRF250 that we couldn't find the actual match in the Bible of alloys, but you can look at an older spec like MIL-H-6088 and generally see what needs to be done. Solution treat at ~ 860-900F for ~ 40min for .090 thick and quenched in boiling water. This gets it to W condition and you follow with an age hardening of ~240-260 for 24 hours. The problem I see is the different alloys involved. I'd bet the down tubes are of 6XXX which has a higher temperature age and less hours. You HAVE to brace all of your areas where you don't want it to pull in especially the engine cradle and make sure there are zero blanked off spaces that can build up pressure as the will expand and split the frame. You'll have to polish the frame as it'll look like shit afterwards. there are newer specs like AMS2770,2771, and 2772 which supercede this one but they didn't reinvent heat treating on aluminum and charge for their specs. I choose not to heat treat my AF project and I have a very nice heat treat faclility with all of the furnaces and dip tanks needed and in accordance with AMS2750 pyrometry. If I can I'll try and bring in a CR125 chassis I have and zap the down tube to make sure.
Craigus

cryzsurfer wrote:The Y section was a 7XXX series on my 04 CRF250 that we couldn't find the actual match in the Bible of alloys, but you can look at an older spec like MIL-H-6088 and generally see what needs to be done. Solution treat at ~ 860-900F for ~ 40min for .090 thick and quenched in boiling water. This gets it to W condition and you follow with an age hardening of ~240-260 for 24 hours. The problem I see is the different alloys involved. I'd bet the down tubes are of 6XXX which has a higher temperature age and less hours. You HAVE to brace all of your areas where you don't want it to pull in especially the engine cradle and make sure there are zero blanked off spaces that can build up pressure as the will expand and split the frame. You'll have to polish the frame as it'll look like shit afterwards. there are newer specs like AMS2770,2771, and 2772 which supercede this one but they didn't reinvent heat treating on aluminum and charge for their specs. I choose not to heat treat my AF project and I have a very nice heat treat faclility with all of the furnaces and dip tanks needed and in accordance with AMS2750 pyrometry. If I can I'll try and bring in a CR125 chassis I have and zap the down tube to make sure.
Craigus

X 2 At the time I built mine, I decided there was more risk than reward
not knowing material type of all the components of the frame castings tubing etc. With that said, If I were going to do a full tube replacment, I would anneal the tubing, bend and cut/fit, reheat treat to T6.
Just an FYI for anyone interested, I just had a left over piece of my down tube (03 crf450) checked in our metallurgy lab at work today. It came out as being 7019.
I forgot to add also, i did a hardness test on it also and it checked 67-70
Rockwell B scale. also checked a piece of 6061 T6 angle I had with me and it checked 55-57 B scale.

as for the crf250 it sounds like crzysurfer has some of the chassis parts figured out. i would hate to even guess if other gen bikes are the same.

as for the heattreating, i always thought they were but it was just a guess as i didnt know for sure. a while back i talked to a metallurgist who made a very good point that i never thought of before. in order for honda to heat treat every chassis they would also need a seperate facility to straighten every chassis afterwards. that would add time and money to the process. these bikes arent hand made like a rolex watch, theyre mass produced. metalurgist was leaning more toward stress relief after welding as it would be much simpler for mass production, rather than heattreatment.

Thanks Everyone for the input. I know the co. I do work for understands all the info provideda as they do areospace work. At this time I a leaning towards stress relieve and if more info is avaliable later, we can all benefit. THANKS AGAIN, Bob

5356 fill rod will give you better strength than 4043 heat treated

nmdesertrider wrote:5356 fill rod will give you better strength than 4043 heat treated

im no welder but from the info ive read neither one of those are worth a shit if you plan to heattreat post weld. aparently 4643,5180 were specifically developed for situations were treating will be applied.

That's cool to know the grade of the down tube as I misplaced the pieces I cut out. As far as fillers go, I stayed away from the 5356 because I used DC with pure helium on my project and it really sucks to weld with that process on any of the 5xxx be it base or filler. Maybe because of the magnesium content. I made sure to get 100% penetration on all joints and had rectangular solid stock to slip in the cradle tubes to act as a backing to tie into much like a chill ring on piping. I don't plan on jumping the Tennessee River so maybe it won't break.
Craigus

100hp honda wrote: in order for honda to heat treat every chassis they would also need a seperate facility to straighten every chassis afterwards. that would add time and money to the process.

I'm guessing they use jigs to keep the frame from warping to shit. I'm like you in seeing all the little relief holes in the frame. They without question use some kind of post weld heat process. What that process is I guess is the million dollar question we all would like to know!

The relief holes are to keep the end of the weld from blowing out.

Of all the AF conversions done on the 2 sites also adding the KX contingent there has been fuck all failures in the Af practice of back yard mod's...(The British bike being the exception, & i'd suspect that was a professional job by the final build quality.)

If you want to heat treat your frame thats good but you should realy know what your doing.....i recon its a waste of money IMO in conparison to the failure rate, ive seen hair line cracks, in mounts, & the rear sub frames crack but i've seen this on standard AF125/250's as well.

So do we realy need to do it..................................................................

asteroid500 wrote:Of all the AF conversions done on the 2 sites also adding the KX contingent there has been fuck all failures in the Af practice of back yard mod's...(The British bike being the exception, & i'd suspect that was a professional job by the final build quality.)

If you want to heat treat your frame thats good but you should realy know what your doing.....i recon its a waste of money IMO in conparison to the failure rate, ive seen hair line cracks, in mounts, & the rear sub frames crack but i've seen this on standard AF125/250's as well.

So do we realy need to do it..................................................................

its your bike, do with it as you wish. doesnt matter what the failure rate is, sooner or later someone is going to get hurt or killed, its innevitable. we need to find out with 100% certainty how honda built these chassis at the factory, then we will know how to procede forward. i dont have time to build my AF twice or repair cracks or broken mounts, so im doing it right the first time....... which ever way turns out to be the right way, im determined to find out.

100hp honda wrote:

asteroid500 wrote:Of all the AF conversions done on the 2 sites also adding the KX contingent there has been fuck all failures in the Af practice of back yard mod's...(The British bike being the exception, & i'd suspect that was a professional job by the final build quality.)

If you want to heat treat your frame thats good but you should realy know what your doing.....i recon its a waste of money IMO in conparison to the failure rate, ive seen hair line cracks, in mounts, & the rear sub frames crack but i've seen this on standard AF125/250's as well.

So do we realy need to do it..................................................................

so im doing it right the first time.......