Quote: from Kevan on 9:57 am on Feb. 4, 2001
I think you're right about the 4130 though. *You left out a few things in your cost analysis-
3. Machining of the bushing slots
Can you do all that and keep it under $25 Canadian? *:biggrin:
Hey Kevan, I mentioned the machining of the bushing slots so yes, that includes that which would also mean I included labour. *To cut the parts on these bars is ridiculously simple. * If I was doing more than one or two, (enough to warrant a production run) They would be around $4.00 each, machining and forming included. *If it was a production run of a couple hundred, the finishing (has to be a plating, you can't anodize steel) would only be about $1.50 a part for a grand total of (gasp, omigodno) $5.50 so with mark up, I'd maybe sell them for $11.00 :biggrin:. *If doing it by hand, I could do everything for the $25.00 I mentioned, if I was thinking of it, I'd send it in with some other job that is being plated and get it done too so it might cost me $26.00 but I think if I really wanted to I could do the machining and forming in about 20 minutes so maybe it would only be $21.00.
Then!, if I really wanted to get fancy, I could heat treat the steel, make it hard (which gives it a nice black chrome look, no jokes here Kev LOL) and then anneal it so it isn't brittle. *That would take about 5 hours in the furnace but once I turn it on (no jokes again) I go away for a few hours just coming back to cool it and temper it.
and if I wanted I could fit a few bars in the furnace. *
Just so no-one asks, NO!!! I'm not going into whammy bar production!!!!
Oh yeah Kev, one thing you might be forgetting is the rod to make the bars out of, you can buy it in a nominal size (otherwise it wouldn't be drill rod :biggrin
so all that you have to turn is the bushing grooves, the chamfer on the bushing end, and the radius at the far end.
BTW if you're curious how they could be done for $4 in a production run,
1. loading the part in the CNC - 30 seconds
2. CNC turning the part, 30 seconds
3. Moving the part for the parting operation - 20 seconds
4. parting operation - 10 seconds
5. forming the first section in a punch press - 10 seconds
6. forming the 85 degree section in the brake - 30 seconds
7. any final hand de-burring - 30 seconds
So 2 minutes and 40 seconds later, you have a part ready for plating.
That = $2.40 for the part and I'm figuring on $1.20 for tool wear.
The only downside to the production run is this
Cost of CNC programming, (cheap for this part, maybe $30)
Cost of building form tool for first bend, probably around $700
Cost of building fixture for forming in the brake, $300
So the first one is expensive, but the truth is, if I'm going to make 10,000 parts, it ain't that bad!
(Edited by littlegreenman at 12:54 pm on Feb. 4, 2001)