ADA: Ask Doc Anything!

[Siress]

What's the most complicated mathematics you've busted out for paintball and are willing to share?

[DocsMachine]

Which Paintball gun (In your opinion)had something really going on, but just got a close but no cigar award. Missing the mark in execution or some other huge flaw.

-I could write a book on that subject alone.

While there's several strong contenders, the one right off the top of my head is Sheridan's Equalizer. That was very much a promising design, that was committee'd to death.

While it had several poor design decisions (the plastic grip frame with no bottomline or tank-mount option, the insistence on a back-bottle fitting when even back then everyone was going vertical air, etc.) the big one was the literal committee decision to redesign the trigger valve from the original.

For those that don't know, a fellow by name of Evan Scott (if I recall correctly) was the primary designer of the Equalizer- the same guy that designed the rotary-breech Phoenix. His design for the EQ included an internal, Automag-style vertical trigger valve.

Wasn't anything like the Automag valve, didn't work the same way as an Automag valve, and the Automag valve wasn't patented or copyrighted in any way, anyway, but the boardroom bandits at Sheridan were terrified that they'd start to produce this gun, and AGD would slap a monstrous lawsuit or something on them for copying the valve.

So they redesigned it to be the external valve with the truly idiotic seal and mile-long air passages we all know and love today.

That is, they basically intentionally crippled the gun, in fear of a lawsuit over a part that wasn't protected anyway.

Some of the other factors- primarily the aforementioned plastic grip frame- were going to hurt the gun anyway, but at the time, with an actually fairly narrow supply of good semiautos in general, players would have put up with at least some of that. The gun would still have flopped, but maybe not so spectacularly. But what the players would NOT put up wit, even in the dim, dark days of 1996, was an ROF nearly as slow as an un-autotriggered pump.

The mechanism had potential- maybe not "change the game" potential, but definite market value, at least in those early days. I've thought for years that I'd love to redesign the gun back to maybe what it should have been, and see how it performs. But I'd have to make about 80% of the gun from scratch, and I've simply never had the time for that.

Doc.

[The Great Equalizer]

Fascinating history for me.

I feel that the trigger pull on the Equalizer trained me to have a "fast finger" on all subsequent single trigger guns I've used. Against my original group of 12 players in middle school (Stingrays, Pro-Lites and Spyders) I had the second fastest ROF using an Equalizer. The one guy with the cocker was faster. Did I get shootdown to the point that the balls were landing at my feet? Yes. But they were still landing at my feet FAST (or at least that's what I remember from 25 years ago).

I'll also note that Sheridan did a really bad job educating retail stores and their own customer service people. I wanted a longer barrel soon after getting my Equalizer and the store owner told me there were no barrels longer than the stock barrel. I called Sheridan and I was told the 8" stock barrel was the only barrel for the Equalizer. They didn't advertise the Equalizer in magazines and I don't remember seeing a picture of the actual thread on a VM barrel in a magazine, so I assumed they were right. Three years later I found this tiny shop in Worcester MA that had an un-ported barrel with a thread I recognized. I'd never been so excited when the clerk explained that the VM was one of the most popular guns of all time and there were hundreds of different barrels. Of course I bought the one he had and it defiantly improved my accuracy for the 3 months until the Equalizer's final death.

[DocsMachine]

What's the most complicated mathematics you've busted out for paintball and are willing to share?

-That's easy: Calculating the tap-drill size for 15/32"-32.

Mathematics is not my strong suit. It's not even an old ratty suit in the back of my closet I only wear once every eight years. I know it seems odd for a machinist- especially one that works in fractions, decimal inch and metric on a regular basis- but it's the truth. I am highly reliant on a calculator even for simple stuff, it's just not the way my brain is wired.

I can stare at a mechanical device and almost intuitively understand how it works, and can diagnose most mechanical problems just by ear, but numbers in general are NOT my friend. I've come to terms with common fractions and decimal-inch conversions just from regular use, but if it involves geometry or trigonometry or really, even just most algebra, I gotta get out Google, a calculator and some scratch paper.

Doc.

[WORR13]

what would you recommend for a lathe table? ive got a south bend model 9a, 3 1/2' bed that ive been wanting to get up and running. workbench? with butcher block? or ??

[dartamon]

-That's easy: Calculating the tap-drill size for 15/32"-32.

Mathematics is not my strong suit....
Doc.

See, you say that, but that brings me back to the vert feed calculations on the old Tinker's Guild FAQ (that I maintained for a year or two):

https://web.archive.org/web/20031205...enterfeed.html

Now the last phrase "There will be a quiz in Dr. Nickel's class next Thursday." I thought always alluded to you having written it. Was it Have Blue or someone else?

[DocsMachine]

See, you say that, but that brings me back to the vert feed calculations on the old Tinker's Guild FAQ (that I maintained for a year or two):

-Whoa, that takes me back. I'm pretty sure that was probably written around 2000.

Now the last phrase "There will be a quiz in Dr. Nickel's class next Thursday." I thought always alluded to you having written it. Was it Have Blue or someone else?

-It refers to HB, but I seem to recall that Guild regular* Curt was the one that wrote up several math-based posts.

It definitely wasn't me, since my level of math, even today, is a lot closer to 2+2= somewhere around 4 or so.

I should repost that. I know Curt came up with one at some point that did the math to figure out the maximum theoretical ROF. That is, if the paintballs could leave the barrel with just enough separation to keep them from hitting each other, what would the maximum ROF equal. The answer, as I recall, was something like 25,000 BPM.

But the bolt would have to be moving at supersonic speeds, you'd need [some ungodly number] of cubic feet per minute of air, and so on. Oh, and the G-forces subjected on the ball to load, chamber and accelerate, were far and above that which the shell could survive.

I know I have that article somewhere, I saw it on one of my archive drives just a few years back. I should dig those out and repost them.

Doc.

[Lazarus78]

what are some of your guilty pleasure bands/songs? ones that if someone heard them on your playlist, you'd be slightly or very embarrassed?

[DocsMachine]

what would you recommend for a lathe table? ive got a south bend model 9a, 3 1/2' bed that ive been wanting to get up and running. workbench? with butcher block? or ??

-All you really need is "something sturdy". Don't worry too much about making the strongest possible table. The lathe won't care.

Yes, something heavy and well-braced is nice, but really won't help your accuracy or surface finishes much. I know some people have liked maple-topped tool chests from Home Depot and the like, but those are usually mounted to casters, and any mass or stiffness from the top is lost with the casters being a little floppy. They're not cheap, either.

If it were me, I'd consider making a custom table out of simple 2x4s. Splay the end legs like a sawhorse to add a little stability, make the top out of maybe a couple sections of 2x6, or three or four 2x4s, have a shelf at shin height both for bracing and tool/chuck storage, and have a well-attached X-brace at the back to rigidize the whole thing. Half a day's construction, maybe $100 in materials if you don't have any laying about.

You can make it at your personal favorite height, the open base lets you stand close to the machine without stubbing a toe on a cabinet, and if you're tight on space, a narrow base will save space over a large tool chest. (Though you get the storage of the tool chest, so there's a tradeoff.)

Barring that, check your local Craigslist, Salvation Army and/or garage sales for a cabinet, table, old entertainment center, leftover kitchen cabinets, etc. that you can beef up with a few planks and some plywood.

Or if you have the cash to spare, a Husky tool chest from Homey-Dee works a treat. I've seen guys take the casters off and set the cabinet up on blocks of 4x4, but if it were me, I'd make sure they're secured, so the cabinet can't "fall off" of them.

Doc.

[DocsMachine]

what are some of your guilty pleasure bands/songs? ones that if someone heard them on your playlist, you'd be slightly or very embarrassed?

-Got a bunch of those.

As I noted in another post, I'm not a "music snob". I like my music, you might not like it, that's life. I'm no fan of Aerosmith, but they still sell out whole stadiums.

Now, keeping in mind that none of these are on my current playlist, and haven't been there for years- decades, in some cases- my MP3 drive contains such songs as "Barbie Girl", "Safety Dance", and Weird Al's "Dare to be Stupid".

I actually have a lot of Weird Al, but like a lot of the others, they're very-occasional songs. They're not the kind of thing you'd want to listen to on a regular basis- frankly, once a year is almost too much. (I've ranted about this before, songs like AC/DC's Big Balls, Wynona's Big Brown Beaver, and Jackyls' Lumberjack are all parody songs. They're jokes. And like a joke, if somebody tries to tell you the same joke twice a week, it pretty rapidly goes from funny, to barely humorous, to stupid, to "I'm gonna kill him the next time he tries to tell me that".)

I also have some classical, both original and rock/techno remixes, there's some Nickelback in there, I have some Simon & Garfunkel, old White Zombie, some old KISS (but I repeat myself- all KISS is old! ) and some even older Jimi Hendrix. (Which isn't exactly embarrassing, but hey, the dude's been dead for fifty years. He was a decent guiatrist back during the Gemini missions, but we've recorded new music since then! Play some of THAT. I've already heard "Watchtower" five hundred thousand times. [fleck spittle] )

[Cues up FFDP's, Inside Out to calm down]



Doc.

[goofyman23]

Any thoughts on doing the Air Cure Cerakote at home? Building a cocker and trying to do as much as possible myself.

[DocsMachine]

Any thoughts on doing the Air Cure Cerakote at home? Building a cocker and trying to do as much as possible myself.

-Unfortunately can give no data on that, as I've never used it. Only thing close to that is years ago I tried a bake-on "Moly Kote", that worked, but was a significant pain in the sphincter to apply. And needed like 400F to cure, so you couldn't apply it to plastics or soldered parts.

I'm sure there's others here on MCB with more experience who can answer your question.

Doc.

[dartamon]

BTW, do you machine the swoop drop forwards yourself or farm them to a CNC shop?

[DocsMachine]

BTW, do you machine the swoop drop forwards yourself or farm them to a CNC shop?

-With the exception of a few of my bulk retail products, everything I make is done by me, in my shop.

I designed it, I cut it, I milled it, I polished it, I bagged and boxed it, I labeled it, and I mailed it.

The only thing I didn't do is lick it. As far as you know.

Doc.

[DavidBoren]

How often do you trim your toenails?

If I got a Metadyne Thumper, could you make it work?

What is the airspeed velocity of an unladen swallow?

Have you ever done any work on/for a ZAP 600E?

Want to?

[DocsMachine]

How often do you trim your toenails?

-Once a year, whether they need it or not.

If I got a Metadyne Thumper, could you make it work?

-I'm not God.

What is the airspeed velocity of an unladen swallow?

-With or without an Estes model rocket engine jammed up it's tailpipe?

Have you ever done any work on/for a ZAP 600E? Want to?

-Sure. I have a wide selection of hammers.

Doc.