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Messages - stealthbikebags

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Hello,

Whether through personally experience, or through the latest "Cool Guy" gear page, almost everyone here is aware of the fact that laser cutters have been making an appearance in gear shops of all sizes. I recently (past 6 months) began cutting my patterns on a laser at the local TechShop here in Pittsburgh, and it's made a world of difference in time and quality of product. The downside is that the membership to TechShop is relatively expensive, and it's not always available at the times I would like to use it. So I began looking into a laser cutter of my own.

After looking into commercial laser cutters, I had trouble finding a laser that would really do what I wanted for the following reasons:

1. Footprint: Most cheaper (cost<10,000USD) commercial laser cutters had a relatively small footprint, typically in the range of 24-36". While this would certainly fit most of the panels for pouches, it was a touch on the small side for items like belts and large packs.

2. Power: In the few cases I did find a machine that had a cutting bed size I liked, the power was usually scaled up accordingly. I have no need for a 150W, water-cooled RECI tube. A 40W tube should do almost anything needed, and a 60W tube at full power has been enough to cut two layers of any material I can stick under it in a single pass.

3. Precision: Part of what drives the cost of these machines is the tolerances to which they are designed to operate. While tight tolerances are great for many applications, these machines typically operate in a tolerance range that would fit several times over in the width of the pencil lines most of us use to mark our patterns in. For myself at least, a few millimeters (+-2mm) of slop over the bed of a large cutter would be un-perceivable in the final product. I don't want to pay for precision I don't need.

Lastly,

4.Cost: All of the above factors add up to a machine that either couldn't do what I wanted, or one that was far out of my budget as one man operation.


So I began looking into home built laser cutters, and found that there are a number of good articles on designing and building a home machine. I've got a good amount of information collected, and have begun to build some of the machine structure in SolidWorks. But before I go too far into the design, I had the thought of making this machine an open source project. I want to gather information from the members here on what features or constraints others would want to see in a laser cutter designed specifically for our environment. Some examples are the following:

1. Ability to feed the entire width of a standard material roll: I've got a source for 1800mm extruded linear track, and will be using that for one axis of the machine. This should allow the machine to take the entire width of a roll of material, reducing the need to cut the material to fit the laser bed. I mean the whole point of the laser is to reduce cutting time, so I don't wanna have to cut material to reduce cutting...  :)

2. Top cover that is a usable work table: The machine will take up a considerable square footage of the workshop, and I don't want to loose all of that working space. The top of the machine will have provisions for mounting a working surface.

3.  Variable speed ventilation: When cutting simple Cordura, the amount of smoke produced is low. A high speed fan is not only unnecessary, but can actually cause pieces to be sucked up off the cutting bed when they are cut free of the main fabric. Conversely, when cutting hypalon, we want the fans cranked up to take that nasty chlorine gas away as quickly as possible. So the ventilation system should be adjustable by the user.

4. Manual cut bed height adjustment: The vast majority of what I am cutting is Cordura and Hypalon, and for the most part a singular focus height can be used for both. On the rare occasion I need to adjust the focus height, a simple manual adjustment system would suffice. This would cut out the very expensive third axis most commercial laser cutters have.

5. Target price of 2,500 USD: I believe this would put the machine within reach for most small operations, and the more serious hobbyists among us.


I would like to take the time to gather input from this community, and see if there would be interest among the members of the community in developing such a machine. If there is interest, I will incorporate feedback from the community, and document in detail the progress of the effort. Once completed, all information in regards to the project will be available for any who would be interested.

Constructive criticism is welcome and requested. If I'm wasting my time, I'd appreciate the heads up. :)

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Hey!

Ok guys, I had a crazy idea this week... Trying to make an "addon" for the straight stitch sewing machine to convert it to a programmable tacker by attaching it to the table!
Still at the stage of reflection, but I played a bit with 3d software to validate the idea with some coding... And here's the result in video:
http://sendvid.com/jtrsbpxi



The purpose is to be able to load some pattern with positions and move the fabric as a tacker would do. The software should be pretty straightforward now that I made the cartesian/polar coordinates conversion with offset for the arm length etc. Still remain the issues of synchronising the machine servomotor with the fabric movements and actually making the parts to hold and move the fabric. I'm thinking of doing so with 2 stepper motors and asking a friend who owns a CNC machine for the mechanical parts... And since the servomotor got a needle positionner that can drive the needle up/down and detect the position of the wheel I hope to be able to hack it so the software can control it...

Or course the patterns would be unlimited... Just need to take some time to list the points position
http://sendvid.com/nwhizu1w

Next step is to make some test with the servomotor :)

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