My little project

[y0da900]

The SLG uses air in front of the bolt to reset it, like an Ion or Hollowpoint. The difference being that there is a restricted orifice in the bolt that lets the chamber pressurize using the same gas that pushes the bolt back, and the air is supplied constantly with a bias actually pushing it forward, hence the need for the restriction in the orifice. And it is sear tripped.

[Hilltop Customs]

wow, never thought of that.....the bolt I posted could be used the same way if it was used without the rear o-ring that I mentioned be4....only change needed would be the inclusion of a sear and a constant supply of air to both orifices.

[Hilltop Customs]

Well thought I would update this, been busy with school so I havent done much at all. New bolt design/body w proper o-ring dimensions is done, redoing a back cap and asa now, but the asa attachment is giving me a lot of crap because of limitation of materials and the internal complexity of the asa/body interface. Imagine a cocker with the ram and 3 way both integrated into the body/asa mate

Anyway I have to find some type of gasket that will work as a crush seal at an operating pressure of around 200psi-300psi. Or even better yet figure out what type of o-ring to use for a gasket type seal(not circular, but a recessed radiused groove). Basically need to find a thin o-ring with a fairly large circumference. On McMaster-Carr 1/16" is the smallest size offered to fill the length requirement. I think it will be good as long as I design the groove with ID of the groove to match the ID of the o-rings circumference.

I'm designing up 2 versions: a standard top fed(no longer integrated feedneck), and a warp integrated marker(not just warp body like the ULE ).

After I get some time to work on this project over the weekend, I'll put up something more fun than just a description.

[snoopay700]

Hmm, that's similar to some designs i've had before, no clue about your new design though, i have an inkling as to what it could be but really don't know. I remember coming upon the threshold a while back and dumping one of my designs simply because something like that had been done before.

I'm fairly certain my new idea hasn't explicitly been done before, but it does borrow idea from other markers (i'm fairly certain i can use one of their stock boards hooked up to a new solenoid) and it's all par of my quest to make the smallest and most shot to shot efficient marker, however it won't get as deep into the tank as some other markers, unless i can actually do what i was thinking about which would allow me to shoot until the tank is empty, but i know people won't be crazy about that idea.

[Hilltop Customs]

ahhhh this design is driving me nuts......and now my xp computer(the one solidworks is on) is running reaaally slow. Might have to go on campus to work on this tonight or tomorrow because this is just painfully slow. I started working on the G-code for parts that will not change....the bolt and a couple small ram parts for now, more to come next week. I still havent gotten to the redesign of the grip frame to incorporate the feed design I'm going to go with aluminum panels for this, mainly because no current grips provide rigidity to the grip frame. Also with aluminum panels I can greatly reduce the required internal girp frame material. I am thinking of doing something crazy with some of that rubberizing paint, or some thin layers of rubber and adhesive if I'm not happy with the aluminum grip surface.

Just a note to myself....need to incorporate a mechanical safety

[Hilltop Customs]

well, I officially accomplished nothing this weekend....I'm working on a redesign of a coconut cutter prototype and it is simply wasting all of my time since it is a group project. Wasted 7 hour today.



Just a little rant about this project:

Penn State makes it's senior industrial engineers work on a capstone consultation project.... in this case mine is a coconut cutter(woohoo ) Anyway we are allocated $1000 to work on this project, but I found out Penn State requires a payment of $2500 from the companies we are doing this work for. Not only that, they SELL our intellectual property to these companies for $250 a group(or $62.50 per student/semester), which I find incredibly devaluing as a student/engineer/person.

I dont mind working for outside companies for free, I dont even mind giving away the intellectual property rights for anything developed over this semester, but when Penn State profits from my work as a student, that crosses the line. I am paying this college for my education, they have no right to profit from my work as a student......and they should have no right to SELL my intellectual property. Giving away is a different story.

/rant

oh fyi, the projects arent limited to little things like my coconut cutter(I just chose it because prototyping and product development is something I'm interested in), there are groups working for major companies like UPS, FedEx, Army subcontractors, and some steel companies.

[y0da900]

well, I officially accomplished nothing this weekend....I'm working on a redesign of a coconut cutter prototype and it is simply wasting all of my time since it is a group project. Wasted 7 hour today.



Just a little rant about this project:

Penn State makes it's senior industrial engineers work on a capstone consultation project.... in this case mine is a coconut cutter(woohoo ) Anyway we are allocated $1000 to work on this project, but I found out Penn State requires a payment of $2500 from the companies we are doing this work for. Not only that, they SELL our intellectual property to these companies for $250 a group(or $62.50 per student/semester), which I find incredibly devaluing as a student/engineer/person.

I dont mind working for outside companies for free, I dont even mind giving away the intellectual property rights for anything developed over this semester, but when Penn State profits from my work as a student, that crosses the line. I am paying this college for my education, they have no right to profit from my work as a student......and they should have no right to SELL my intellectual property. Giving away is a different story.

/rant

oh fyi, the projects arent limited to little things like my coconut cutter(I just chose it because prototyping and product development is something I'm interested in), there are groups working for major companies like UPS, FedEx, Army subcontractors, and some steel companies.

I accomplished snapping the drive belt on my lathe about half an hour into a new prototype that I could have probably finished in the day otherwise

Don't feel bad, most schools will do what they want with any IP you generate as part of a class. My senior design project we designed (and built) a machine to delaminate the growth rings on trees for the local Mohawk tribe to use in basket making. Worked pretty well too. We never patented it because none of us understood that new use warranted a new patent, and it was designed around the concept of a trip hammer taken from iron working (flywheel, leaf spring, hammer). If we had, the school would have kept the patent for themselves (which was typical of any IP generated in senior design), not sure if we would have even received any royalties on it.

Basic patent law needs to be incorporated into the requirements for ABET accreditation for engineering.

[Hilltop Customs]

the thing that gets me is they say "you can refuse to give away your IP, just choose a project which doesnt require the signing over to the company" but there was only one project which didnt require the signing over of IP(which filled up instantly).....but the catch is, the IP is still Penn State's property whether or not we sign anything, not the students. In essence when we sign over our IP to the purchasing companies, we are not signing over anything of our own, just property of the university.

and they wanted a donation for the senior class gift to the university I think they have made plenty off me already......I'm going to take great pleasure in tearing up every piece of alumni mail I receive.

That sucks about your belt, I hope its not too hard to find a replacement. What kind of lathe/mill do you have?

I'm really interested in purchasing at least a mill to convert to cnc when I get out of school. Converting the mechanism and the motor control/feedback loops seem simple, but I havent looked too far into controllers(software or stand alone)....have plenty of time for that though.

[y0da900]

the thing that gets me is they say "you can refuse to give away your IP, just choose a project which doesnt require the signing over to the company" but there was only one project which didnt require the signing over of IP(which filled up instantly).....but the catch is, the IP is still Penn State's property whether or not we sign anything, not the students. In essence when we sign over our IP to the purchasing companies, we are not signing over anything of our own, just property of the university.

and they wanted a donation for the senior class gift to the university I think they have made plenty off me already......I'm going to take great pleasure in tearing up every piece of alumni mail I receive.

That sucks about your belt, I hope its not too hard to find a replacement. What kind of lathe/mill do you have?

I'm really interested in purchasing at least a mill to convert to cnc when I get out of school. Converting the mechanism and the motor control/feedback loops seem simple, but I havent looked too far into controllers(software or stand alone)....have plenty of time for that though.

When my school comes crying for money someday, I'll have a few questions for them about what they have done to improve student life, if I don't like the answers, they get no money. Running out of hot water for the entirety of the freshman dorms on almost a weekly basis is not good.

It's just a typical 9x19 lathe from Grizzly, I already ordered some replacements from them. I wish I had taken the belt with me (lathe is at my parents) because I think replacing it from mcmaster-carr would have been much cheaper. My mill is just a regular mini mill, also from Grizzly. The lathe I like for the most part, the mill - I wish I had waited until I could have afforded a nicer one, or at least afforded the nicer upgrade parts for it like a reduced backlash screw and nut assembly.

[Hilltop Customs]

wow the more I work on this coconut cutter project, the more I realize that this is not engineering.....

First off all communication with our client must first go through the professor for revisions(want to talk about a waste of time.....developing a product requires constant communication, this is the exact opposite). Secondly, we have proven that the base design which was given to us is not viable for many reasons, including price of needed components and customer demands. I quote the professor "just tell them what they want to hear"(meaning tell them its a good product and continue developing it)........WTF, this is supposed to simulate a real life situation, because for our customer it is a real life situation. If I was paying for this project and found out that the management(aka the professors) were telling the engineers to "tell me what I wanted to hear" I would be furious. This is the exact opposite of what we have/are being taught, it especially conflicts with everything I have learned in concurrent engineering.

Even the speaker we had in the capstone class(past president of Lockheed Martin, and a man who developed his on consultation firm) stated that there is a temptation to tell a customer what they want to hear, but good consultants do not let that affect their decision making. He also stated many other things that have been contradicted by our management in the first week of this project.

I was looking forward to developing something, not telling someone what they want to hear. Talk about a disappointment. I discussed this with my group, and they all agree that this project could have been great, but the miss-management is simply destroying this opportunity.


Sorry for the rant, I have to vent somewhere or I'm going to snap the next time I have to meet with this professor.

[Hilltop Customs]

Well finally got some good news, prototyping has been approved by my CAM professor. I verified that anything developed in the class is still my IP. And I had a classmate join the group for helping with the machine code/machining the parts)Ordering materials on Friday. Also found out I only have to model a couple little things in Pro-E(just verify I can use the software), so that makes me a happy camper.

[snoopay700]

Well finally got some good news, prototyping has been approved by my CAM professor. I verified that anything developed in the class is still my IP. And I had a classmate join the group for helping with the machine code/machining the parts)Ordering materials on Friday. Also found out I only have to model a couple little things in Pro-E(just verify I can use the software), so that makes me a happy camper.

Can't wait to see it. As for your design the only thing i can suggest (if it's similar to your old one) make it electric, cause if you short stroke it it can bloomp a shot.

[Hilltop Customs]

thats something I'm willing to risk on the prototype, plus it will allow me to do testing to see if there will really be a problem with short stroking.

with my newest revision, by the time the bolt resets(and a ball can drop in the chamber) the dump chamber should be partially recharged. so required dwell between bolt reset and next shot should be minimal.(the dump chamber begins filling very shortly after the bolt reseals with the stem on the rearward stroke of the bolt)

but it is definitely in my mind if there is any short stroking issues. But before taking that step I would like to test variants of the bolt and stem to eliminate any possible short stroking.

I'm trying to keep the design as simple as possible and keep costs absolutely low as possible. A board would be something I would have to outsource, noid would have to be outsourced. It adds cost and complexity.....and the only benefit it brings(if the marker is designed for minimal short stroke issues) is really modes and a mouse click type trigger.

[snoopay700]

thats something I'm willing to risk on the prototype, plus it will allow me to do testing to see if there will really be a problem with short stroking.

with my newest revision, by the time the bolt resets(and a ball can drop in the chamber) the dump chamber should be partially recharged. so required dwell between bolt reset and next shot should be minimal.(the dump chamber begins filling very shortly after the bolt reseals with the stem on the rearward stroke of the bolt)

but it is definitely in my mind if there is any short stroking issues. But before taking that step I would like to test variants of the bolt and stem to eliminate any possible short stroking.

I'm trying to keep the design as simple as possible and keep costs absolutely low as possible. A board would be something I would have to outsource, noid would have to be outsourced. It adds cost and complexity.....and the only benefit it brings(if the marker is designed for minimal short stroke issues) is really modes and a mouse click type trigger.

Well i had a fairly similar design in the works, and had it drawn up horrndously, but Tom still took a look at it and it was all mechanical and he said that that was one of the problems he forsaw, but if i made it electric i'd have to pay royalties to SP, as i imagine you probably would too.

[Hilltop Customs]

yea, thats another one of the things I was trying to limit also. IDK about their royalties, but I'd think that a board/noid conversion would have a lower fee than a whole marker since they would sell at a much lower value than a complete electronic marker. IDK, I'd like to avoid paying someone else for my work every way possible....

this is all really hypothetical thinking at this point, I'll be more worried about that in a month or so, depending on this giant waste of time coconut cutter project.