ADA: Ask Doc Anything!

[Super Nova]

Are you still doing custom work on pball markers? We talked a long while ago about doing some work and I have acquired the bodies, been trying to contact ya to see if you are still in the biz and interested. LMK thanks.

[XEMON]

Awesome, thanks 👍
I may give them a go to hold me a bit while I wait to find the right mill (a small knee mill, Rockwell or alike would be a dream 😜)

[DocsMachine]

Ever use something like that?
it seam like an easy/good way to drill tubing on center (which I always struggle) on the lathe.
Anyone have or used one?

-I've never used one, but I've seen them used. They get the job done.

Keeping in mind my first machine tool was a mill-drill, and it was a while before I got a lathe. Drilling the center of something is easy on a mill, of course.

Doc.

[DocsMachine]

Do you think a "6 way" valve (like the g force gemini kit) that would thread into a standard front block would be a marketable product at this point in time?

-The reason for the Gemini system was to have a softer closing pressure than cocking pressure. As for it being a "marketable" product, considering that the company itself couldn't succeed in marketing it, back when 'Cocker were the pinnacle of tourney technology, I'd say no.

It's the kind of thing that if you made five or six, you might find buyers for most or even all of them- especially if you included the matching front block.

The answer I’m hoping for is “I’m about to find out, I”ll sell you one and name it after you.”

-I wouldn't mind giving it a try, but I have so many other things on my plates right now I couldn't even guess when I'd be able to get to it.

Doc, can you make a .50 caliber autococker?

-Easily. The original Snipers- the very first ones- could actually be ordered as "multi caliber". You could order it in .50, .62 or .68, or even get a "kit" that let you swap between all three.

The way Bud did it was the two sub-caliber barrels had a significantly extended breech, that when screwed into the gun, extended past the feed neck. The barrels had to be "bored in place" so there was an opening that lined up with the feed neck, meaning the barrels were matched to that body.

After that, you had a bolt that had a stepped-down nose, where the back half was normally sized, and the front was reduced diameter to fit in the barrel.

Doing kind of the same idea today? I've been asked this several times, and it's comparatively easy. I'd make a sleeve with a step at one end, like a long top hat. That would slide into the 'Cocker breech, with the rim coming to rest at the base of the breech where it meets the barrel bore. Bore the feed neck through (side or vertical, doesn't matter) and drill and tap through for a normal ball detent.

You'd have to make a slightly extended detent to reach in and still work against a .50 cal ball, but the extended detent would also lock the inner sleeve in place.

After that, the aforementioned stepped bolt, which is easy, and then a .50 cal 'Cocker barrel. Eclipse used to make kits for Eteks and the like, back in the day, so something like that, if you could find one, would be ideal.

Optionally, find a .50 cal barrel off of just about anything else, and make an adapter to allow it to fit the 'Cocker. A third option would be to make a .50 cal insert that goes in a Freak barrel. I seem to recall- but have not confirmed- that 1/2" thinwall hobby brass tubing is ideal for a .50 cal barrel- you just need to sleeve or reinforce it somehow, so it's not too fragile.

... Geez, does anyone even still make .50 caliber anymore? Just checking eBay (it's quick and easy) virtually everything listed is pepperballs, steel shot, or "less lethal" plastic balls. I found a blowgun dealer that had some- which is almost certainly crap quality, and one seller that had a couple cases of Valken 50. Which I'd wager is probably five years old by now, or more.

Doc.

[XEMON]

Ever use something like that?
it seam like an easy/good way to drill tubing on center (which I always struggle) on the lathe.
Anyone have or used one?

[Savet]

Doc, can you make a .50 caliber autococker?

[k_obeastly]

Do you think a "6 way" valve (like the g force gemini kit) that would thread into a standard front block would be a marketable product at this point in time?

The answer I’m hoping for is “I’m about to find out, I”ll sell you one and name it after you.”

[DocsMachine]

I don't recognize any of it, no.

I assume you mean specifically the hack-job midblocking? No, definitely not mine.

Doc.

[nadrepadre]

Doc, did you have a hand in this?

[Walker]

Thanks Doc... I've already replaced all the "tarnished" parts, so I'll try a bit of light polish, and see what happens.

[DocsMachine]

It's just tarnish. Nickel is mostly resistant to oxidation, but not not entirely. Ever heard the old term "triple chrome"? That meant the platers put three layers on a part: a layer of copper, which 'fills in' slight scratches and tiny pits, the layer of nickel which gives the bright silver color and the main protection to the part, and then a layer of chromium, which gives the part it's brilliance, as well as "sealing" the nickel from oxidation.

It's basically like painting a car- the copper is the primer, the nickel is the color coat, and the chromium is the 'clear coat'.

In most cases, nickel by itself is suitably durable even for all-weather use. IE, Palmer's Typhoons and the like.

But, in some cases- and in my experience especially over aluminum- if not applied well, and not cared for properly (stored in high humidity, paint or other gunks left on it for protracted periods, etc.) it can easily tarnish.

It's also possible that the nickel was applied much too thin (poor plater or just as an attempt to save money) and the aluminum is tarnishing under the nickel.

The only restoration is maybe trying some metal polish. Flitz or Brasso or Mother's, etc. Scrub a small spot and see if you can buff off the tarnish- if you're careful, you might try light power tools, like those little felt polishing discs and cones that come with Dremels.

If you're just making the tarnish shiny, it's the aluminum, and there's no way to save it except by deplating and replating, or deplating and then anodizing.

If the tarnish does go away, keep in mind you've actually removed some of the nickel, which was probably very thin to start with, and the aluminum may oxidize under it.

Doc.

[MrBarraclough]

So basically, zero-G paintball would turn into the battle room from Ender's Game.

[Walker]

Hiya Doc,

What causes this type of damage to nickel(?) finish? Is it recoverable, or does the finish need to be removed somehow?



Looks worse in person, and it was every nickel finished piece on the gun.


Walker
(sorry for the poor pix. My camera skills are ok, it's the lighting that gets me)

[DocsMachine]

How would zero gravity paintball games differ from current modes of play?

-Zero gee, but still shirtsleeve weather (IE, indoors) or zero gee, in space?

As noted, no ball drop would be the big one, but if there's an atmosphere, range is still limited due to drag. In outer space, of course, that rope you fired at your opponent would keep going until it hit something, or was pulled in by some gravity well.

At only 200 MPH though, it'd take a couple centuries just to pass the orbit of Pluto.

Now, either way, the actual play style would have to change a LOT. I mean, if you jump up into the air, you need some way to either stop yourself, or at least change direction. Thruster packs? A couple extra 114 tanks with little adjustable gas jets? Might not be enough thrust to properly dodge. More likely the field would have to be basically 3D airball, with the bunkers (or solid shields, maybe) on some sort of support structure or scaffolding, or a whole web of support ropes.

Something sturdy enough that "flying" players could grab and hold, or "jump off" from, but with enough give or elasticity that "crashing into" one wouldn't hurt. Masks would have to be much better secured.

Other issues: It would be possible to run into floating paint, and at the end of the day, there'd be "clouds" of spray and random balls floating about. You'd have to take Spock's advice and start thinking 3-dimensionally; else you could get flanked overhead or from underneath.

[/As a machinist, how often do you do an operation by hand?
I don't mean break the corner with a file on the lathe, I mean, clamp the part in a vice and file/cut something by hand (like squaring a hole ...)

-Pretty much constantly?

I'm an old-fashioned machinist, both in how I learned/was trained, and in the equipment I have. Save for the feed necks, which I made on my new-to-me CNC lathe, every bit of those Vee-Twin bodies has been done on manual machines. The only "automated" part is the power feed on the X axis. Hundreds of manual tool changes, thousands of turns of the cranks, constantly keeping track of dimensions and spacing and sizes, trying to work out the order of operations 'on the fly'...

In the first Vee-Twin video...

You see pretty much exactly how I make a part. That's not staged or mocked up- I was recording the actual work. As I said, the only "automatic" action was the power feed for the table- everything else was 100% manual and pure brainpower.

Doc.

[Grendel]

This question made me think of my Dad. He would not let me touch either the mill or lathe until I had made a cube with right angles and flat surfaces with hand tools (tested on a flat table with precision angle gauges and dial indicators down to +/- a 0.001. Learning to lap surfaces is a great skill to learn. I remember my Dad making many parts by hand for prototype mechanical assemblies. In particular remember him hand scraping the ways for a LeBlond lathe he bought from work for his home shop.