Bikeguide.org - Bike maintenance for BMX'ers
The Street => The Lounge => Topic started by: MilkyWilky on December 18, 2014, 09:47:34 PM
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SORRY - I took the photos down, just thought it best. Thanks for all the input. PM me if you're really curious. I'll post something when it's done.
Sup BG. Maybe not the right place for it but I have faith in the collective knowledge of the guide, and I want to hear your thoughts.
A few weeks ago my school was contacted to design a trophy for some Clean Technology business award. We had a few students taking part and some instructors and technician. After breaking off into smaller teams we went with 3 concepts, and of those 3 mine was chosen. I intended it to be wood with aluminium placards, but the program coordinator insisted we also include a render in chrome, despite my argument that it would be a bitch to make.
So as I planned to move home before Christmas I had made it clear that I'd be gone when it wrapped up, but since it was chosen I have to at least line up the fabricators and clarify design issues.
The base is nearly impossible to make, but I have some ideas of how a waterjet might cut it. (concentric rings at an angle) and for this we will either do it this way, only every other ring, or alternating metal and wood. Any thoughts welcome.
What I'm struggling with is how I will attach the 10 large metal plates to the central spindle. It's a big straight pipe with enough wall diameter for tapping, and the plates themselves may be around 1/4". Originally some brazing was going to be the ticket, but it would be too tight to get in there after half the plates.
About to tell the clients we will have to use countersunk connector bolts, but it does look shitty.
Anybody know of a simple, strong, good in tight spaces fastener? Or a stud bolt with RH and LH threads?
Any leads appreciated, and no leads appreciated too. Thanks
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Couldnt a good machinist make you some RH&LH-thread studs/custom fasteners?
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Couldnt a good machinist make you some RH&LH-thread studs/custom fasteners?
That was my thinking, pop a little knurl in the middle and just threading the tapped plank to the pins holding it. Likely the simplest solution, and clean too, thanks!
Any other wise-guyz?
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The base is nearly impossible to make, but I have some ideas of how a waterjet might cut it. (concentric rings at an angle) and for this we will either do it this way, only every other ring, or alternating metal and wood. Any thoughts welcome.
where are you? are there any places around you that can 3d print metals?
(http://i.imgur.com/6VySg5g.jpg)
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Looks like a building out of Mass Effect.
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I'm in Vancouver so it is likely, I guess I should mention the scale, it's about 16" in diameter at the base, and 32" in height. I think to 3D print suck a thing it'd be quite expensive and honestly the finish of the 3D printed metals I've seen so far, it looks a bit hopeless.
The two options are to cut sections of bar stock with the right measurements and roll them into a ring, finish with a weld. What I was thinking, to cut two wedge blocks, and from each cut a set of concentric rings at 70* angle. pop them out, stagger and stack them. A waterjet has the added bonus of pretty clean cuts with minimal finish. Also could cut the green top pieces from the material at the center.
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Looks like a building out of Mass Effect.
Also, I've never played Mass Effect, but it was supposed to be somewhat futuristic, citylike, but the area is a 'city of glass' and O guess they want MORE highrise buildings.. From different angles it changes like a skyline blah blah blah, if it was made out of reclaimed wood as intended it would really say something interesting. Bittersweet.
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If I were building that at work, my first thought would be to hit up our foundry and see if they could cast it. Maybe cast it in three pieces, do the surface finish, than assemble them with a large bolt through the middle.
But since they would either tell me no, or if they said yes, I wouldn't like the price, I think I would stick with the three pieces. Either size the ID of the column large enough to get a ratcheting wrench in there, or cut access openings opposite each of the stud that would be hidden behind the plates when assembled, but are accessible before the three pieces are assembled. If you use socket cap screws, you could get away with some pretty small holes and make some little plugs to fill the holes once the plates are attached.
Then I would tell the designer who drew the thing that I would appreciate it if he considered producability before designing insanely cool looking shit. :P
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Also, upon further inspection, you could use those wood inlays to hide your fasteners. Cut a groove 1/8" deep or so, fasten the plates to studs brazed to the columns with flathead screws, epoxy strips of finished wood into the groove.
I think this is my final answer.
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Hard to say without the sense of scale, sounds pretty big, so either make four sections and bolt together down the centre (and you can do all your fastenings of the outer plates from top and bottom before bolting sections together). Or use the wood inlays to hide the heads of fasteners, you could dovetail them in there if you wanted to be fancy.
For the conical bottom, I would turn rings then machine the angle, then weld links on the inside and then glue in the wood inlays to hide the links. If you are going with the gaps then just weld the rings at the bottom where they meet.
:)
G.
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I make this kind of stuff all the time. ( I'm a machinist and do high end architectural and artwork fabrication on the side.) Like G said it's hard to tell with scale but i've done something similar.
- Depending on the thickeness of the materials. You could dovetail the wood and metal. Rigidly mount the wood to the pipe then slide the metal pieces on for a clean look.
- I've done word standoffs and soldered studs to the back so they can thread into the wall. You could do something similar to the pipe.
- You could do a sleeve style. Instead of a single straight pipe use three different OD's. (Larger to smaller from bottom up) weld/solder/bolt studs to each OD of pipe and do each layer fastened to a piece that's ID matches the corresponding OD. Then simply stack the sections off of the base. (Hard to picture I know)
There are a ton of different ways you could do it. But it's hard to help without knowing your budget or accessibility to tools or machinery.
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So the scale is around 16" base diameter, 32" tall, or around 40x80cm. Capabilities will be sought out as needed, since the program is design, our workshop caters mostly to prototyping things and woodwork. It's for a fairly substantial business prize (~10 cheese) and will be used for at LEAST 10 years, so that amortizes nicely.
The model does have dovetailed wooden placards and a channel that would be cut in after the plates are rolled, but the issue is the slot is located at about 1/3 of the face, and not the center, so running a bolt behind it isn't ideal, because of the weight some people have indicated it should be connected at the center back, they want people to hoist the trophy proudly. Think it would be an issue? It would be a thin section if it was dovetailed too, the shortest bit I've seen has been 3/8 x 45*, out of a 1/4" sheet, with a good countersink, doesn't leave much.
What I'm thinking now is to braze on the the connectors with a threaded insert to the central shaft first, and tap the back of the plates with a reverse threading. If a machinist can knock up double sided forward and reverse threaded stud bolts with a knurled barrel or something in the middle, I'm thinking they could just screw together (both directions at once)
As for the bottom, If the waterjet has this level of multi-axis articulation (anybody?) it could cut this:
(https://farm9.staticflickr.com/8666/15872806140_49a3b92417_c.jpg) (https://flic.kr/p/qbChgo)GVCT2 Base concentric rings cut (https://flic.kr/p/qbChgo) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
That would probably be a few less man hours than doing 10 on a lathe, and profiling this way you could just profile the aluminium block once. Also waterjet has a pretty good finish I understand. We are on a bit of a schedule.
I like the idea of facing the base with the wood, might be a sneaky way to shave some weight too. Might leave it empty as well, but I really think the design is better with more wood. I also will keep the idea of doing the center in a few sections in mind, but would rather not have to worry about making that look all good n shit reassembled.
Since I've brazed before that's probably what I'd prefer to do, but things start to get pretty tight when the pieces are all on. Worry about working on the backside. Maybe I misunderstood.
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So the scale is around 16" base diameter, 32" tall, or around 40x80cm. Capabilities will be sought out as needed, since the program is design, our workshop caters mostly to prototyping things and woodwork. It's for a fairly substantial business prize (~10 cheese) and will be used for at LEAST 10 years, so that amortizes nicely.
The model does have dovetailed wooden placards and a channel that would be cut in after the plates are rolled, but the issue is the slot is located at about 1/3 of the face, and not the center, so running a bolt behind it isn't ideal, because of the weight some people have indicated it should be connected at the center back, they want people to hoist the trophy proudly. Think it would be an issue? It would be a thin section if it was dovetailed too, the shortest bit I've seen has been 3/8 x 45*, out of a 1/4" sheet, with a good countersink, doesn't leave much.
What I'm thinking now is to braze on the the connectors with a threaded insert to the central shaft first, and tap the back of the plates with a reverse threading. If a machinist can knock up double sided forward and reverse threaded stud bolts with a knurled barrel or something in the middle, I'm thinking they could just screw together (both directions at once)
As for the bottom, If the waterjet has this level of multi-axis articulation (anybody?) it could cut this:
(https://farm9.staticflickr.com/8666/15872806140_49a3b92417_c.jpg) (https://flic.kr/p/qbChgo)GVCT2 Base concentric rings cut (https://flic.kr/p/qbChgo) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
That would probably be a few less man hours than doing 10 on a lathe, and profiling this way you could just profile the aluminium block once. Also waterjet has a pretty good finish I understand. We are on a bit of a schedule.
I like the idea of facing the base with the wood, might be a sneaky way to shave some weight too. Might leave it empty as well, but I really think the design is better with more wood. I also will keep the idea of doing the center in a few sections in mind, but would rather not have to worry about making that look all good n shit reassembled.
Since I've brazed before that's probably what I'd prefer to do, but things start to get pretty tight when the pieces are all on. Worry about working on the backside. Maybe I misunderstood.
If those are just 70 degree lines being cut out of a flat plate a waterjet can cut them as long as the machine is 5 Axis. But to get the 30 degree?? on that plate you'll either need to have it machined or surface or Creep Feed ground. To get the best finish i'd suggest surface ground (surface grinder can get you to a 32 finish.) If you weren't in Vancouver i'd give you a quote for the entire job.
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Thanks, Even just what you said about the surface grind gives me a good idea of what I'll tell the shops on Monday. Could the plate be profiled before the cutting? Obviously it must cut from a 3D format on a 5-ax, so to place the bottom plane of the base flat on the axis might it still interpret the non-regular curve?
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http://www.mcmaster.com/#standard-threaded-rods/=v3otpi (http://www.mcmaster.com/#standard-threaded-rods/=v3otpi) nice
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Since the 3d image of the inside is gone I cant be sure, but with the dual threaded rods you may have problems assembling if they are offset by an angle on the same piece.
I noticed the size you quoted before but hard to get an idea of how thick the plates were from that. Head pulling through could be an issue as you say.
Right now (without the pictures to remind me) I would think that your best bet is sections already fixed to the central column then bolted from the top. You could simply machine each section entirely from a big billet...
I have never come across a full 5 axis water jet, I dont think that is going to work. 3d printing may be a better option here, though it will need a substantial amount of hand polishing to finish and you are likely to loose the crispness of your edges to a small degree.
:)
G.
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(https://farm8.staticflickr.com/7555/15444131954_0fe85ae8bd_z.jpg) (https://flic.kr/p/pwKdn9)split view (https://flic.kr/p/pwKdn9) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
I definitely worry about that, the holes being offset. I thought maybe there would be enough give to cold set it into the right position. The two holes on the planks should be aligned. Maybe a good jig to hold it would help keep the tapping straight? Likewise for putting the arms onto the central column, as they're all spaced the same distance.
As for the 5-axis, I thought it was pretty similar to the cuts used to make propellers, which I've seen done.
I'm having a hard time imagining what would be bolted from the top, that's if I were to split the central column for assembly?
Thanks
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(https://farm8.staticflickr.com/7555/15444131954_0fe85ae8bd_z.jpg) (https://flic.kr/p/pwKdn9)split view (https://flic.kr/p/pwKdn9) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
I'm having a hard time imagining what would be bolted from the top, that's if I were to split the central column for assembly?
Thanks
So make 5 parts/assemblies.
1. The base with the rings. In the middle of this put a threaded boss.
2. Lower shield-plate things and part of central spine. Can be turned from a big billet, bored out between outer shields and inner-core most of the way through leaving a flange in the centre; then put on milling machine to separate shields, create inlay grooves and bore away sections of flange to leave spokes. Screws on to base boss.
3. As 2, just with the next level of shields. Screws on top of section 2.
4. As 3. Screws to top of section 3.
5. Top cap, screws on.
Hope this helps clarify.
:)
G.
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Post the pics back up....
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Post the pics back up....
(https://farm8.staticflickr.com/7577/15898237128_68816eff2e_c.jpg) (https://flic.kr/p/qdSC1G)1218 Basea (https://flic.kr/p/qdSC1G) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
(https://farm9.staticflickr.com/8648/16083754701_ae8b8fcb60_c.jpg) (https://flic.kr/p/qvgrVx)1218 BaseE (https://flic.kr/p/qvgrVx) by MilkyWilky (https://www.flickr.com/people/69574360@N02/), on Flickr
We spoke with the most promising fabricators today and their machinist, and while we had figured out what we needed and wanted to do, the amount of work and the rediculous lead time (less than 30 days) was more than they could fit in with their current workload. I think the story will be the same at most places.
I'm not too choked because I originally wanted to make it from wood, reclaimed and salvadged, using metal for the placards (that are wood in the renders) and I emailed a badass letter to my supervising professors saying I'd like to tell the guy the truth, and offer to make one with wood planks (maybe ~2 polished ones) and a wooden base with some polished accents. Not to get all hippy dippy but it's a trophy they've indicated would have a 10 year lifespan (thus 10 planks) and I think because they wanted something 'as sustainable as possible' they'd be so far from that as it stands. Shiny, yea for sure, I see why they would pick it out of the other ones, but I think it'd be more interesting with a bunch of different woods. Also lighter and easier to do with our shop., which would be a good experience for any student that would want to help out. Pimp hand strong.
G, huge thanks for everything, that way would definitely work well, but I'm hoping they'll give us the freedom to try and do really something special. I might pass that on to the machinist and see if he'd have time to run something like that.
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Thats cool, looks like most of it, including the base (with some concessions), could be done on a laser tube cutter? Would cost a fraction of getting all the stuff machined.
Find some 3-4mm thick stainless pipe the dia of the largest ring, cut out a slightly orange segment shaped profile for the bottom one (to give you the tilt), then each ring above, make it a C shape with progressively bigger gaps in the C <-- , bend those closed, weld them up and hide the joins behind the plaque on the front. Rest of it is all fairly basic tube cutting and wouldnt cost much, biggest challenge will be finding stock tubes.
You could put the chamfers on manually, but sounds like a ballache to me, i doubt it would detract from the overall look much if you left them off.
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What up guys. Thanks again for all yall's input on this. I learned a real lesson on this one, and I hope I never need any help from anybody ever again. Thought I'd let you know how it all ended.
After I left Canada for Basel in January, another student, instructor, and technician took over the project. Some comporimises were made in order to meet the deadline, and in the end it's more or less true to the original intent. I'm actually pretty glad the base ended up being made of wood. Seems like anything else would have been a bit of a waste.
The trophy was given away and they hoisted it up gladly, and it was a great bit of press for our school and the Product Design program.
Cheers.
(https://farm8.staticflickr.com/7305/15860709724_d08aa5c573_o.jpg) (https://flic.kr/p/qayhqu)
(https://farm8.staticflickr.com/7425/16457256366_cab886830c_o.jpg) (https://flic.kr/p/r5gJXq)
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Nice work. They skipped a few things as you said. Metal features on the base, and the wood trim between the metal panels looks quite a bit thicker. I'm happy to get the satisfaction of seeing the end of this one.