The Offcial Machinist Thread: Revised 01/04/2014

[Technician1002]

It defeats the MOAR POWER of the larger stuff. The tiny stuff is fast and low power... Who would be interested?

High speed particles from the implanter can be stopped by a wafer and is embeded just into the surface to make shallow high speed transistors. Have you tried to carry an implanter very far?

[pipeboyswe]

I have a lathe. Anything over 3" dia costs extra, and anything over 4" dia needs to be short and have some spindle mounting provisions

I also have a big mill with rotary table.


Cost is (reasonable) material+postage+custom tooling+nominal labor fee

Lets call it (with tolerance of +-0.005 dia and length/width and +-.01 true position) this:

o-ring groove - $3
boring a cylinder (under 2" long)-$ 5
boring a cylinder (over 2" long - $7 ( and lead time for me to buy tooling)
turning piston - $4

Exotic materials and tighter tolerances are extra. I should be able to hold +-.001 on the lathe, and +-.003 on the mill. Tens of millionths at work, but I don't have access to them .

I would need a 10mm bullet mold (3 cavity) made in aluminium, something like the one in gippetos tutorial http://www.spudfiles.com/forums/easy-sp ... 17366.html no handels just a simpel cheap one what would it cost in round numbers? and i live in Sweden.

Actually, that would be quite expensive. It needs custom tooling or CNC for the nose (unless the standard ~118* point is fine). Is one spout for each bullet okay?

Figure 8" total of aluminum bar (all I have is 1x1.25, with no ability to rip cut) - $4
2" 1/2" aluminum for locating pins - $1 (if that)
spade bit - $4 (not sure)
grinding- tolerance dependent; I think I have a radius gauge, but no CMM or optical comparator, maybe $3

drilling/pressing: $5 maybe (5 total holes)

cleaning the basement to the point where I can access the machines again and setting up the grinder: priceless

so like $17 plus shipping from NE ohio

Hmm that was not what i expected, 17$ + shipping One spout is fine, and is a spade bit necessary? cant you just use a sharpish drill just to make it simple so the nose of the bullet gets kind of round it dosent need to be that sharp. And skip the locating pins and go with 4 holes + bolts. What do you think?
What would be needed to make a bullet like this one?
http://t3.gstatic.com/images?q=tbn:ANd9 ... CwfJbmOAaA
Nice how to

[ramses]

Either way, it's custom tooling. That second method could actually be harder, because my lathe is so small. Especially if you want the rings toward the base of the projectile.

It's not likely to be stable from a non-rifled barrel, either.

[POLAND_SPUD]

great idea

@jsr
machining stuff for others would be one way to improve your skills

[jackssmirkingrevenge]

machining stuff for others would be one way to improve your skills

If I'm charging money for my services, it has to be a decent product, and I'm not that confident yet.

[POLAND_SPUD]

If I'm charging money for my services, it has to be a decent product, and I'm not that confident yet.

not everything will be very comlicated... I guess that most ppl will order a piston with o-ring grooves or something like that

[velocity3x]

Hmm that was not what i expected, 17$ + shipping One spout is fine, and is a spade bit necessary? cant you just use a sharpish drill just to make it simple so the nose of the bullet gets kind of round it dosent need to be that sharp. And skip the locating pins and go with 4 holes + bolts. What do you think?

Your project needs to be made on a CNC mill. No custom tooling required.....just a ball nose end mill. Considering the cost of CAD-CAM software, computer, programing time, CNC milling machine and actual run time etc., etc., this option isn't available within your budget range.

Your best option might be following Gippetos example and hope to duplicate the result but, I'm sure even that method will cost more than $17.

[Gippeto]

Your best option might be following Gippetos example and hope to duplicate the result but, I'm sure even that method will cost more than $17.

$17 is a heck of a deal IMO. Making a mold with proper machine tools results in a MUCH nicer end product too.

I wouldn't want to pay a "Wouldbe Dentist" to learn on my teeth.

[ramses]

Your project needs to be made on a CNC mill. No custom tooling required.....just a ball nose end mill. Considering the cost of CAD-CAM software, computer, programing time, CNC milling machine and actual run time etc., etc., this option isn't available within your budget range.

It could probably be done with a ball end mill and a drill press, but you still need the ball end mill (which I don't have, sadly, especially in 10mm). With CNC, you could do it with any ball end mill less than 10mm. A good ball end mill seems to be going for like $15 in the US, ($120 on McMaster)

Edited by jrrdw, fixed quote tag.

[jackssmirkingrevenge]

not everything will be very comlicated... I guess that most ppl will order a piston with o-ring grooves or something like that

I was discussing this with LeMaudit, some projects which you might think are straightforward to machine are actually quite challenging, I can say from my recent experiences that there are a heck of a lot of things I never considered - so there might be some frustration ahead for both parties.

My suggestion would be that requests be made publicly on this thread, including posting of drawings. I doubt there will be the sort of "I'll make it for $5 less!" competition as this isn't really a commercial venture, but it will allow those with machining experience to critique the design and spot potential pitfalls while suggesting improvements.

I wouldn't want to pay a "Wouldbe Dentist" to learn on my teeth.

Here dental students offer teeth cleaning and other services for free in order to get experience

[velocity3x]

A good ball end mill seems to be going for like $15 in the US, ($120 on McMaster)

McMaster is a great place but, not the place to buy machine tooling. MSC carries quality tooling for less than McMaster. Enco (an MSC subsidiary) has even lower prices but, not the high end items and vast selection carried by MSC.

[ramses]

A good ball end mill seems to be going for like $15 in the US, ($120 on McMaster)

McMaster is a great place but, not the place to buy machine tooling. MSC carries quality tooling for less than McMaster. Enco (an MSC subsidiary) has even lower prices but, not the high end items and vast selection carried by MSC.

I'm aware. That's why I mentioned that I could get one on eBay for $15.00 + shipping. And I think that was an Iscar (USA made and expensive)..

In all fairness, the one from McMaster was fine grain solid carbide coated in TiAlN.

[LeMaudit]

My suggestion would be that requests be made publicly on this thread, including posting of drawings.

I second that

Making a clear and precise drawing is a work that should be done first. It is mandatory for any kind of machining work. Possibly there's some things that a machinist will want to change afterward to simplify the making, thus reducing time/cost and maybe adapting to material at hand. People could also suggest simplifications, again with a machining point of view, and this will be great for non-machinist users to read and learn why a complex design can be easy to cut, and why a simple design may be impossible! It would also be great to learn from advises and how-to for wannabe machinists like JSR and myself

Talking about myself, it would not be a question of cost, but more a question of time. The less time I'll have to spend on a design, the more chances there will be that I can help someone. Cutting is fast when you know exactly what to do.

[ramses]

My suggestion would be that requests be made publicly on this thread, including posting of drawings.

I second that

Making a clear and precise drawing is a work that should be done first. It is mandatory for any kind of machining work. Possibly there's some things that a machinist will want to change afterward to simplify the making, thus reducing time/cost and maybe adapting to material at hand. People could also suggest simplifications, again with a machining point of view, and this will be great for non-machinist users to read and learn why a complex design can be easy to cut, and why a simple design may be impossible! It would also be great to learn from advises and how-to for wannabe machinists like JSR and myself

Talking about myself, it would not be a question of cost, but more a question of time. The less time I'll have to spend on a design, the more chances there will be that I can help someone. Cutting is fast when you know exactly what to do.

Thirded, although I can understand where people would be leery about posting "secret" designs for contests and such.

Also, post TOLERANCES!!!!! If I need to hold +- 1 thou, it will take longer, but if I can have 50, it'll be a breeze. Also keep in mind the tolerances you actually need. You don't need +- .0003 diameter on a ~.2" hole 1.2" deep that will hold a roll pin that I will be pressing in! (but tell that Eaton corporation)

[dewey-1]

Also, post TOLERANCES!!!!! If I need to hold +- 1 thou, it will take longer, but if I can have 50, it'll be a breeze. Also keep in mind the tolerances you actually need. You don't need +- .0003 diameter on a ~.2" hole 1.2" deep that will hold a roll pin that I will be pressing in! (but tell that Eaton corporation)

.050 is a rediculous tolerance for a machined part!
1/16 is .0625, close to a carpenter's tight tolerance.

I hope you meant .005.