Quote:
Originally Posted by Leo.G
Wow, I was thinking you had 5 stud tube rings.
You mentioned boring the centres, what diameter hole are you going for in your calculations?
Too close to the spokes will weaken the overall design.
Would you be better going to a hub design you bolt the already stud holes to the hub for overall strength (unless they have been machined down to a flat surface).
I guess you are trying to maintain strength while keeping mass down?
Still, it's an impressive machining job and no easy undertaking I'd assume?
My lathe wouldn't even do mini minor rims, 300mm swing over bed but 700mm between centres.
Sadly I studied fitting and machining as an aside to fabrication engineering along with hydraulics and pneumatics back in the late 90s and still had a lathe for maybe 10 years later that but had to get rid of it during an emergency move into emergency accommodation. (Cert 2 in each I think, Cert 3 in fab engineering, arc, MIG, Tig, Oxy and fabrication design and loadings, I honestly don't remember which certificate for the 3 nights per week for 2 years for machining and hyd/pneu and have no idea where my paperwork is, I have no need of the qualifications, I can't work anyway.
We now have our own little Chinese thing in a garden shed up the back yard which came as a kit with a bolt on milling machine but I didn't like that idea because it's very restricted functionality so I bought a nice compound table ($1,000) (ForestWest have some nice gear for good prices) and a good vice and had my engineer friend drill and tap the cast bed of the compound table (I hate tapping cast iron, don't mind welding it when I have the correct blow torch handy for pre and post heating (and an oven for the rods) but I hate tapping the stuff. He did a great job on it but now I have to weld up a table/stand for the machine and I'm confused with my dimensions. I was going to make it the full travel length of the compound table but that's not really necessary and I save a lot of materials with a more compact size. I have 40x40 SHS, 4mm wall thickness and I have some 50mm (or 75, I forget) c channel with a 6mm flange and I was going to put that across to mount the compound table and mill. The more rigid the build is the better the milling finishes.
My main problem is getting the steel to bend a swarf/coolant tray because I'd like to add a recirculating pump to the coolant and eventually convert it to a CNC unit. No trailer or ute and delivery of a 1200x2400mm sheet is rather expensive.
That takes brains and money, I'm short of one and thin on the other, lol.
I really need to get it done soon. The lathe weighs 300 KG (small unit) and is standing firm on a stand I welded up (thankfully, I over engineer everything for strength, part of formerly being a forklift technician and car hoist specialist/technician over the years.
It's going to be a very interesting build when you get it all finished!
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The reason for machining out the centres into one larger hole was purely for aesthetics, one hole will make it look less like a car rim that has been recycled. The large hole will cut out all the 5 smaller holes completely and leave the entire spoke design, there is plenty of meat left on the bone and the strength will not be affected I wouldn't think. Centre hole will be about 160mm in diameter.