What could I machine for my ATC70?

[Schlauncha]

I'm in a unique position where as a college student in the Tool & Diemaking program, I have access to all sorts of machine tools, CNC equipment, cad software, EDM, lots of different metals at my disposal, including access to tool steels and heat treating ovens, but as a full-time student I don't have the funds to just buy a 120cc lifan for my ATC70 like I would like to. So I'm wondering if I could just machine upgrades for my engine for effectively free (I'm finished with my projects this semester but still have a week of lab access before winter break) or if there are other things I could machine for other people here, to then trade for upgraded parts. For example, I was thinking I could take the piston and jug off my stock engine, measure them, and scale them up to as large of a bore as possible (52mm?) and then machine them out of aluminum. I would make the jug from a solid hunk of billet aluminum, and then press a steel sleeve into it so that the piston rings have something appropriate to slide on. The jug would get lots of cooling fins courtesy of some CNC milling I would guess. As for the head, I was thinking about taking the head off a Trail 90's motor, for its bigger valves, and then adapting it to fit. If not, at least I would have increased my displacement greatly, despite the limitations of the original head and carb (maybe upgrade to a larger carb since they're like $20 for a chinese knockoff).

If somebody has the designs for something better to make, I'd gladly make two sets and ship you one. Just so long as it's stuff I can reasonably machine (no multiple-cylinder rotary engines please) it shouldn't be too tough. I have Autodesk Inventor 2010, so that can open many CAD files if anyone has something for me in that format.

OR if you are just dying to have some strange odd hard-to-find piece for something else, I could be commissioned to make that instead, so long as it offers a profitability path to eventually put a 120cc motor into my trike.

[Mr. Richard]

hell i know an easy way to make a few bucks pretty quick,,,
make a hundred of these ,,, waterjet them out of 1/4 " aluminum no polish and bang them out cheap,,, make a few bucks each and make a few hundred bucks fast,,, i am in for at least 5 so get to work,,, i would even like to see some 1/2 thick,,,, and it doesn't even need the R in it ,,,

http://i45.tinypic.com/volijr.jpg
http://i29.tinypic.com/345ycm9.jpg

[bob225]

What is that Mr. Kasey. Chain guard?

[FlyingW]

Thats a case saver Bob. Chains love to destroy the 250R left cases when the chain comes off. Cheap insurance by far.

[Mr. Richard]

and its OFFICIAL the cases are discontinued as of now,,,,,

[Schlauncha]

I think I could probably make those, I would CNC mill them out of 1/4" aluminum bar stock, probably set up to drill the holes and then switch to an end mill and profile each part out, usually nested as many as fit in say 1 foot saw-cut length of material.

I can scale most of the stuff from the one photo, but I need to know what diameter the holes are, and what the dimensions between them are. Given the distance between two distant holes, such as the top left and bottom right ones (in the top pic) I could pretty accurately scale the rest of the dimensions from that. Different thicknesses would only be limited by what material I can find on hand there (there's lots of aluminum bar stock, in sizes such as 3" by .25" thick, 8 foot long).

Maybe I could just make as many as I reasonably have stock for (Say, 30 pieces) and sell you all of them, and let you re-sell the ones you don't want? I'm not looking for any long-term profit margin on stuff, I just want a quick one-off job here that can make me some pocket cash for the holidays.

Too bad I don't have a 250R so I can't verify the parts fit until they are all done and on your doorstep...

[FlyingW]

If you have some 6065 or 7071, Id use that. The smaller hole diameter is 7mm. The large hole is to accomodate the shifter shaft which is 14mm so a hole about 16mm. Richard, please validate my my assumptions. Also, it would help if you took a straight on pic with 2 rulers layed next to the case saver on X and Y.

[Mr. Richard]

the small holes 6.5 mm the shifter hole is 15mm not to bad for no graph paper or a ruler....

http://i50.tinypic.com/14ac5jr.jpg

[Schlauncha]

Well I have everything converted over to a series of coordinates using my design software, now I just need to hook up my computer with Mastercam on it and use that to get the actual CNC code... but long story short hooking that computer up is a project for tomorrow, so it doesn't look like I will get any of these ran Monday. Hopefully the shop is still open Tuesday (it's finals week). I hope the dimensions around that biggest curve are not a very tight fit, because for simplicity sake I want as few new line segments as possible (be it a straight, a curve, etc) so I have one large 1.626" radius on the right side there, which seems to best-fit the line you have drawn. The result is that the narrowest portion, there in the middle, is .232" wide. Hopefully that is enough. Also, should I enlarge the 15mm hole for the sake that it is only clearance? Probably better to have more clearance than to end up with not enough.

I could maybe run one or two pieces and then ship it to Mr Kasey, let him tell me how it works to verify the clearances, and then after classes resume on January 11th, I will have lab hours again but there will be at least a week before my classes have lab assignments, so there should be a window of time there that I could use the CNC equipment for my own means to make the rest of them. This way I only need about 20 minutes on a machine to knock one or two of these out, instead of jumping into trying to make a production of these.

Is aluminum the desired material? If it were steel, I could much more easily make a hundred of these on a laser table at my uncle's factory. If composites were an acceptable material, I could just machine a mold and cast these from nylon or an enamel resin. If thickness wasn't as big of a deal, I could make a die set to stamp these out of .060" steel, at a rate of about 20 pieces per minute. Then a person could stack them up to the desired thickness. I'd just run a piece of .5" A2 tool steel through an EDM and let it make my punch and die at the same time (since the EDM wire's cutting kerf is about the clearance between the two anyways), then turn some pierce punches for the holes, and set it up in a progressive die operation so that it first hits all the holes, then slides the stock over the opening where it hits the outer profile, dropping the finished part through the bottom of the die. The cutting periphery (including holes) is 22.366" so the tonnage on .060 CRS would be about 33.5 tons to shear the material, and then you can assume if it's a progressive die, that you will be notching it to progress by 3.5" with usually a .125" notch depth, so that adds another 5.5 tons to the force required, so before considering this option, I would have to make sure the press I have access to can hit with 39 tons of force. I'd probably try to stick with fixed strippers if I could help it, for simplicity and rapid manufacture.

But it would take a serious investment of labor and time to make a whole stamping operation for this part, and even then, the result would be the estimably less-desirable thinner pieces that would have to be stacked up to the desired protective thickness. On the other hand, when it's done, the die would last long enough to easily make a set of guards for every 250R in existence...

For short-run, CNC milling the part will be the quickest and easiest, but if steel is an acceptable material, I could just give you the Autocad file of the part, which you could then take to a job-shop and for a mild investment get them to make you a hundred of them. I just don't know how busy my uncle's shop is, whether it'd be reasonable to ask him if I could toss a sheet of these parts on there to be cut.

The volume of these parts (at .25" thick) is only 1.953 cubic inches, which from aluminum would weigh .191 lbs, or from steel would weigh .554 lbs. It would only weigh 1.362 lbs if you made it from solid gold, but at a cost of $24,319.87 at current gold prices, assuming all scrap gold from machining is resold at non-depreciated value, it hardly seems worth the cost to do.

[FlyingW]

Actually, steel would hold up better under a broken chain flying at warp speed but the aluminium was used for the bling factor but either material is acceptable. I have access to a waterjet at work but I dont know how to use it. My machinist does though so do you know what type of file the waterjet needs to run? I can find that out tomorrow. I can take a CaD file and get one of my guys convert it. If you want to cut some out of steel, I can cut some out of aluminium toot sweet if I had the right file. I'm not wanting to muscle in on your deal, just offering options.

[Gdkarma]

sounds like you guys are on the right path! Jim, you'll probably want a .dxf file to give to your programmer................:thumbsup:

[Vealmonkey]

Here's a suggestion. You could always machine aluminum copies of the factory axle spacers on an atc70. I believe they are made out of plastic, but would be very cool in aluminum and polishable. Now get busy machining and send me a couple sets for the idea!

[Schlauncha]

Hydrojet sounds like entirely the correct way to make these; so much so that I don't see any point trying to make them with a CNC mill for the hopes of turning a small personal profit. The end result will still be that good parts are made, but with much less net labor involved. I don't know how much those parts would have been worth anyways, if they would have been $20 each or if it was more like $20 for 5 of them...

So far the best I can output is .dwg files so here are two of them. Single and a nested pair (nested ones are rotated 45 degrees for better fit).

When I'm at college today, after finals I will try to use their high-speed internet to find a free conversion tool to go from DWG to DXF format. Once I have that, then I should be able to give you guys DXF files for any parts you want, so you can take them to a job shop (or Jim if he's in a Santa-esque mood) and have your parts cut out by laser or hydrojet, or whatever else takes DXF files (CNC plasma tables, CNC turret punches, etc). Hopefully this will help people on here get parts from being sketches on paper, to being actual parts on their trikes, by doing my part to help. I enjoy working with CAD so it's a fun hobby for me to help make DXF's like this. And donations to my paypal account would always be appreciated in return! Anyways, here's the files, hopefully either I can convert them (and post them here) or Jim's guys can make use of .dwg's

Forum won't let me attach a big file... not that 300k is "big" by any means...
I attached it to a post over at the First Lego League forum I use a bunch... hopefully they don't mind being a file host for such a tiny thing for a little bit, until I figure out a better way to host the files (and get them converted to DXF's).

Here is the link: http://forums.usfirst.org/showthread.php?p=34505#post34505

Look at us, being all rapid-prototyp-y and stuff.

[Schlauncha]

Okay I found a dwg to dxf converter that looks like it worked... but I have no way to verify the dxf is any good other than that is appears to be the correct size of file. I put them in a .zip and attached them to a post on the Lego forum. The link in my previous post will still go to it, the .zip of DXF files is just the more recent post on there. I'd email them to you if I had your email (you could PM it to me) but for now this is one way to get the file to you. Hopefully it doesn't require you to register with that forum just to get those files...

The files in that .zip are a single part, and two parts nested. Hopefully they work, if not, maybe you can take my .zip of DWG's from the first post on that other forum, and get it to either open or convert them within your own software. Let me know how/if things work.

EDIT: just tried... you'd have to register to download those... Let me look around and maybe I can find a better place to host them.

EDIT: I got your address and emailed them to you, Jim. Good luck!

[Schlauncha]

Alright, well the 250r case guard project is in Jim's hands now, so long as my .dxf files came out okay from the conversion tool I used, he should be ready to start Hydro-Jetting them out of steel or aluminum of desired thicknesses, at his opportunity. Those of you who wanted them, talk to Jim (FlyingW) and you guys can go from there. Glad I could help.

On to the next project, it's been requested that I make up some billet aluminum 250R tail light LED conversions. Soldering a grid of LED's to make the replacement bulb is probably going to be the trickiest part, and most labor-intensive. If the 250R light housing (not lens) accepts a relatively common automotive light bulb, I might be inclined to just tell a person to head to eBay and get one of their LED plug-in ''Bulbs'' which in the end will save money on the labor I'd charge to make the same thing. A person would just need to add a diffuser lens to make the red be more spread out across the tail light, instead of pinpoints (overcome in the design illustrated by the sheer multitude of LED's being used). I'd carve this out of aluminum on a CNC mill, and the text on the face could easily be changed per customer desires. Until I can model one directly to a 250R light, I can't estimate how much material it will actually take to machine this, but it would be easier for me to make a batch of them (even if it's different names on the lens) all at once, instead of spread out over time. Most likely there will only be a two week window of availability for accepting orders for them.

Attached you will find an image from my design software, of a rough estimate of how the light would look, based on estimating from photos. Wall thickness could be adjusted, currently it's at .25'' but that's only about half a pound of aluminum for the 2x8x1.5 overall dimensions I estimated that piece at. Don't worry about giving me more accurate dimensions, I have a light being sent to me that I will measure from. I should be able to machine these beginning January 11th. All proceeds will go towards my 120cc lifan swap for my ATC70 ''JD3'' trike.

EDIT: Here is a link to one of those LED replacement bulbs I was talking about. http://cgi.ebay.com/2x-1157-BAY15D-RED-24-LED-TURN-TAIL-BRAKE-LIGHTS-BULBS_W0QQitemZ200417672555QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item2ea9d2fd6b

[Schlauncha]

Here is a version of the guard that has the R on it, and is lightened. Since everything is planned to be made by hydrojet, I decided to render this image in carbon fiber (hey, it's supposed to be light weight right?) mostly because it shows details better with a texture, than just flat polished aluminum (like the brake light above lacklusterly shows).