casting a lug for a motorcycle frame
casting a lug for a motorcycle frame
(OP)
is it best to cast a lug for a motorcycle frame or forge it, I am in south africa and would like to repair a motorcycle frame that has been manufactured 40 years ago, any suggestions on how to approach the remanufacturing of the lug/s and what material/s to use, I have been unable to get a replacement frame, I am part of the local VMMC





RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
It is a TR5 Trophy, the lug was cut and altered to change the neck angle in the 60's for a chopper, I have most of the original parts and would like to convert it back to original, thanks for the support
I would still like more info on casting the lug (and the material to use), this way it would be more original
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
Where can I find out more on forging and the tooling required, the material to use in this application is also important
I have acces to machining facilities and if I knew how to design the tool/s to forge a item, the shrinkage of the material and tolerances required and what material to ultimately use for the forging. I think I could cut the cost of a low production forging run
IE I would supply the tool and the material and the foundry would have to do the job
The machining is not an option because the motorcycle would then be of no value
RE: casting a lug for a motorcycle frame
H11 or H13 Hot Work Tool Steel should work for forging.
Whoever you plan to do the forging for you can give you shrinkage info for macAhning the forging tools.
After machining the tools they will need to be heat treated by a competent heat treater. Tool steels require more particular understanding to correctly heat treat than most steel alloys.
Suggest after forging, you anneal the forging. The forging supplier should be able to provide this service for you. Next machine the 4140 then have it quenched and tempered to 38-42HRC.
Jesus is THE life,
Leonard
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
Nick
I love materials science!
RE: casting a lug for a motorcycle frame
As regards China I have no comments except it is killing us too in India.I know of a company in road building equipments who used ductile iron castings made in China and the machines failed in use. They have since been pulled out of service.
RE: casting a lug for a motorcycle frame
My moral is we are still beig driven by two things, Installed fear by forging comapnies who think they will lose out in business and the old school who still see castings as something done in a dirty old place and being a dark art. The casting technology has come a long way and most foundries now have degassing units, spectros, gas analysers, metal cleanliness, x-ray both real time and film. Cad/cam, and solidifcation software.
There was a good article written by boeing CEO that stated he wanted all his people to look at the savings that casting could make over forgings. One example is the wing rib in the new airbus, it used to be forged out of 7 parts and then had the problem of fitting alignment and such. this is now cast. In addition the new audi doo of the A2 is cast as one piece, albeit by thixoforming.
RE: casting a lug for a motorcycle frame
But now it is not possible to get young engineers or technicians attracted and the art or skill in manufacturing is dying,
RE: casting a lug for a motorcycle frame
I was a foundry guy, published in AFS, presented at conference, and got a masters of science from one of the top metallurgy schools in the world. After finishing school I moved to the big city, sent 400 targeted resumes, at least 1/4 of them were in the casting industry. After 1year I had one interview in a foundry, adn even then they were really looking for a manufacturing engineer. I really liked the thermo and stuff of castings, there were no jobs for me thou. Well now I have a great job w/ a good company, and even get to do a little bit of research now.
Nick
I love materials science!
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
I dont know whether it was a casting or a forging, has anyone got an idea or can anyone point me in the right direction for this kind of info
I can manufacture my own tooling and or patterns if I have the tolerances ie shrinkage etc
I assume it was a forging, yet I am not sure
If it is a forging I need info on tool design
Can anyone help me
RE: casting a lug for a motorcycle frame
For my own two-bits on the metal forming process, I have dealt with millions of cast and forged components from every part of this world and have seen porosity in castings from every country, but never in forgings. I still use both.
Have a great day.
RE: casting a lug for a motorcycle frame
RE: casting a lug for a motorcycle frame
Nick
I love materials science!
RE: casting a lug for a motorcycle frame
The one I approached that was supposed to be technologically advanced, using CAM and lost wax process with ceramic moulds - had inclusions visable, that were the size of a rice grain
And this worried me
Last but not least, if anyone who has the knowledge could look at the neck lug of a 1949 to 1954 Pre Unit Triumph and tell me if it is a casting or a forging
The technology debate is very interesting and I am learning a lot
But I would like to remanufacture the lug to original, if possible
Thanks everyone for helping
On a more positive side, many people have approaced me subsequently for more info on this type of frame building and/or repair
And yes the closest thing to this is bicycle frame building