Long story short I just moved and all of my equipment and tools are in a storage unit. So I removed my dash outta my 36 chevy truck and took it to this machine shop. I requested that they evenly drill 2" holes along the horizontal arch at the top evenly. Three weeks later I pick it up and the holes are not evenly spaced and some are oval shaped.What can I do to fix this in your opinion? I thought about having a muffler shop bend a piece of pipe to match the arch, slice the pipe in half and weld it over the arch, the redrilling my holes? Any other ideas? Thanks guys!
I'm picky about my stuff too. If you want it right and can't do it yourself you should have marked exactly where you wanted the holes. If you leave it up to others to figure out what you want...you takes your chances. JMO
Post some pictures of your problem, its easier to find a solution. Round holes in contours very seldom look round, they get elliptical looking.
If the holes are not too far out off whack, you could use a large half round file to open them up to a slightly larger diameter, evening out the location and size at the same time. Also was kinda wonder why the 2 inch holes in the dash, usually the stuff hiding behind that area is better left covered.
Pix will help.. and round holes will have an oval look to them on a curved surface. Look at any part that has a hole drilled on the outer diameter. If the intent was to mount gauges, it might be better to mount those on a nicely machined mounting plate.. by another shop. Bob
Just drill straight thru an angled surface or angle the drill off of 90* to the surface and look at the hole from 90* . Drill a 2" hole in curved pipe and have a look
How many holes? Are they for gauges or some kind of artistic statement? I'm no machinist or industrial artist, but I'd think that cutting numerous holes in a place like that is asking for trouble. I'd only blame the machinist for agreeing to do it. If they're for gauges, perhaps fitting the gauge will help to camoflage the errors.
I agree with seeing pictures. After seeing it, there may be a simple solution to it but without seeing it we are only threading a needle in the dark. Ha Ha! That's a good one, I want one of those too.
I'm wondering why you took sheet metal work to a machine shop? Is this common practice with people? There has to be a sheet metal guy near you that can fix this if you are still unable to do it yourself.
I'd have to be added to the list of those who just have to know why the hell you wanted to punch 2 inch holes in the top piece of the dash in that truck in the first place. from looking at this stolen off the net photo of a 36 Chev truck dash they sure don't need a raft of big holes across the top. What's the plan?
They let the kid who sweeps the floor do it to gain some experience at working unsupervised. Knockout punches for electrical boxes make slick holes in sheetmetal.
If they can't get things right on a drill press...what do you suppose is happening over at the crankshaft grinder??!?
Maybe it got F-ed up because you were as clear with them as you are here. The concise photos show the problem...
The people in automotive shops are just as talented as any other machinist, but their specialty is not drilling holes in a dashboard. If this was an automotive shop, I would bet they could hold a .00010" tolerance on a bore all day long.
But they should damn well be able to lay out a row of start punch marks for the centers of hole saws, and know how to develop X number of divisions of Y inches mechanically or arithmetically! The oddities of a circular cut though a curved plane are not their fault, but the spacing--??
WTF? Automotive machining is about as primitive and forgiving as it gets and automotive machinists only gain proficiency in very few disciplines of metalcutting. Anyone who claims to maintain .0001 all day long is full of **** as the warmth of their hand holding the micrometer will change the reading by more than that without them even realizing it. Truly maintaining such tolerance is well beyond the scope of automotive shops.
Maybe if you explained why you wanted a row of holes there to begin with, we could get a better grasp of the situation.
without pics it's more than guessing, but if I were cutting holes in a curved surface, I would cut from the back side with the tool on the CL of the radius and the piece firmly secured. I'd maybe rough out the hole with an undersized hole saw, then finish it with a boring bar. It's a tough call; I'd have to see it. The hole would still appear to be slightly oblong as has been stated, but it would have nice edges.
Thats why after you drill the holes you replace the pilot drill with a piece of rod so the drill doesnt side cut. And for a project like this I would also spring for a new hole saw as mistakes are hard to fix.
Yes they are. I always use a wooden guide with the size hole clamped to the metal. That hasn't failed me yet up to 6" . Think about that 3/8 bit in a piece of 18/16 gauge trying to keep a 2" hole saw centered 3/8 hole wobbs out and you are all over the place. I'm going to give the "rod instead of drill bit" trick a go and try it.
Amateurs! At the Wyle E. Coyote School of Auto Repair we learned to make oval holes using regular drills. It's easy when you know how!