Homebrew PCBs

Jan, Dave, thanks for commenting.

Dave, I re-read your post five times and to me it was a very dramatic 
story.

I know from your posts that you are exceptionally qualified on the 
subject. Since you have done so much work, have you considered 
writing down plans and selling them. That is exactly what John 
Kleinbauer.com does. Take a look here: 
http://www.littlemachineshop.com/products/product_view.php?
ProductID=2353 He sells plans for retrofitting a minimill, you could 
have your own plans and you already have a yahoo group with great 
following.

I used to have a T-tech that I should have kept for drilling. Now I 
have a Sherline 5000 that has a very long  (7") X but very short Y 
(3"). That is way to short for boards I have in mind. I am looking 
into moving a Z-column behind the base. I posted that message on CNC 
SHerline butit did not post it- I don't know why. Does it make sense 
to place that Sherline on a thick and larger base and relocate the 
base of Z behind the original base? That would gain another 3 " and 
overall would work for me. Maybe you heard of that kind of 
modification. Sherline is an unusually rigid machine and I can feel 
it would be great for PCBs.  Mike




--- In Homebrew_PCBs@yahoogroups.com, "Dave Mucha" <dave_mucha@y...> 
wrote:
> --- In Homebrew_PCBs@yahoogroups.com, "mikezcnc" <eemikez@c...> 
wrote:
> > Dave, thank you for commenting. Have a look at this: 
> > www.easgmbh.de/images/Bgs60.jpg I think it was about 1200 euro.
> > 
> > How hard would it be to make something like that? Parts seem to 
be 
> > mostly from a catalog. I don't see the Y-axis motor, maybe it's 
> > hidden behind the Z... ALso, how to contact Ballendo off list so 
I 
> > don't irritate Stefan for the n-th time? (is dollar sunken so 
LOW?)
> > 
> > Mike
> > 
> 
> Hi Mike,
> 
> I know and use G-code so an X/Y would be much faster for me to get 
up 
> to speed with.
> 
> I just ran thru a design for a 12 x 12 x 2" work envelope machine.  
> it would use $150.00 worth of mechanical parts in the form of 
> aluminum and ground shaft and such.  I figure another $100 for the 
> electronics, so before I look at steppers and lead screws, I'm up 
to 
> $250.00.
> 
> Using all-thread and surplus steppers would up the cost to around 
> $300.00 for a unit that is pretty good.  Using ACME screws would 
not 
> all too much to the cost, but the big factor would be the machine 
> time to drill and tap all the holes to make the unit stable in all 
> directions.
> 
> Since I don't have a milling machine, it would cost me a couple 
> hundred $$ to have all the holes drilled and tapped to get that 
good 
> alignment that would be needed to eliminate poor fits.
> 
> Then assembly of the unit would be a few more hours.
> 
> IF (really big IF) all the motions went perfectly and I got a great 
> deal on the machining and all the parts fit flawlessly I still 
would 
> be over $500.00 for the machine.
> 
> The head on the Z axis is still a question.  There are more than a 
> few ways to actuate that, but since I'm mostly concerned with 
> drilling, it is of little importance.
> 
> I did a design recently for a proposal and used ballscrews and 
linear 
> rails and the cost was close to $2,000.00 for a 12 x 18 x 4 work 
> envelope. 
> 
> If I had access to a milling machine, I would be done already, but 
my 
> access retired last year and moved on to those things old 
machinests 
> do when they retire.
> 
> I had thought of trying to barter with someone who has a mill for a 
> machine, but that is hard to do.  Most people who have a mill don't 
> need PCB's and already to the machining.  
> 
> My Neighbor has a Bridgeport but it is in stoarage as he has no 
place 
> to put it.  When that gets mounted, then I will make my machine as 
I 
> can trade machining time for use.  He's an auto mechanic and I 
spent 
> 5 years working in a machine shop.
> 
> Dave