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Have just had made a stand medallion that replaces the cracked one. Just swaps over and screws in place with the exisitng screws.
I have a small design change to do but if there is interest i could get a batch made up and sell or trade them, not sure on cost yet, need to work out the machining times etc, but could be 15 to 20 euros.
PM me if interested and if enough interest I’ll sort a batch out.

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12 Replies

Cool… looks good! Do you have any close ups of the piece? How’s the strength (if you overextend the stand, like always breaks the N ones)?

DogP

Thats a seriously nice little part. Good idea.

Out of curiosity, did u use a CNC type machine? What material did u use?

I wish I had access to machining stuff. u could sell quite a few of those if they are easy to make. imo i would like black with red lettering. sorry, just my opinion.

DogP: The strength seems good, its a chunky piece of material, some more pics of it removed from the stand included. (took with digi cam with a magnifying loop held in front for a v.close up view)
I do want to add a radius on the angled faces where the legs sit against when open, thats the potential weak point at the moment as its a sharp corner, any stress and it might crack there, putting in a radius removes the corner & the possible weak point.

Pocket: Its actually an engraving CNC machine, not really a mill but due to the size of the parts we can make the machine cut them, not that i can program the machine, I prepare the drawings in CAD and the operator imports them to his package and does the cutting.
The material: I agree 100% it should be black with red lettering. Unfortunatly to get black material would cost quite alot just for a small piece so I ended up buying a chopping board (don’t make black ones though), an inch thick, and then we machined off the top and bottom surface to get the medallion a bit thinner. Not sure exactly what type of material it is, some kind of Polypropolene is my guess, but it machines quite well. The engraving could be better, next lot should improve on that, use a flat face rather than point cutter for the lettering.

Once another batch is made i can work out a proper price for these, I hope it don’t work out too much as I really like the idea that these could resurrect quite a few forgotton units with broken stands.

Hey, Hedgetrimmer, that looks great!

I’m still working on the tool-path for mine (my machine is severely limited in a number of ways, so it takes more work to make a working tool-path).

Hedgetrimmer wrote:

Not sure exactly what type of material it is, some kind of Polypropolene is my guess, but it machines quite well.

It looks more like high-density polyethylene (HDPE) to me, but I’ve seen neither HDPE nor polypropylene in red, so I may be wrong.

I’m actually planning to make mine out of PP. I haven’t cut it yet, but it looks/feels like it may cut even easier than HDPE, which always leaves little burrs around the cut for me (though that may just be my machine/tool/settings).

BTW, how did you do the black logo? Is it an inlay of some kind? Paint/ink?

Once again: well done! (Nice trick with the loupe, too ;-))

  • This reply was modified 13 years ago by RunnerPack.

RunnerPack-
I completely agree, it looks like polyethylene to me, too.

Hedgetrimmer-
Good luck getting the burrs out of it, its nearly impossible. This stuff cant be sanded because its sooooo abrasion resistant. Maybe this can be sanded just because its so little, but the burrs really arent bad enough to lose sleep over.

Its seriously tough stuff though, so it will never break, even if you never radius the inside corners. I have some little scraps, and a piece the size of a pencil can not be broken by hand.

I would also like to suggest maybe a countertop shop… they have scraps from sink cut-outs… a material called “Corian” or the like may be appropriate. It comes in black, and should be machinable. And they will prbly just give you their’ scrap.

Anyhow, thats really nice so far… but heres my solution 🙂
(the medallion in my pic is destroyed)

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@Pocket: Ha! That’s an awesome idea! It took me a few looks to notice what you did. 😛

DogP

I agree with DogP; that is quite a clever solution, Pocket. But, how did you attach the “destroyed” medallion to the clamp? Some kind of glue, perhaps? I also like the little cushions you added to the “knees”. What are those?

Also, It’s probably not a good idea to run much “Corian” through a CNC machine, unless you have a cheap source of carbide end-mills. It’s made from various minerals (e.g. quartz) embedded in resin. Machining this stuff is probably harder on tools than PCB material.

Plus, you’d have to find another way to attach the clamp, since the original screws would definitely not work.

But asking around for free scraps is a good idea. Just go to a plastics fabricator, instead. Your town is bound to have at least one. I live in a small, mid-western town and have two within a few miles of my house. 😎

Hmmm. Youre right, polyethelene is the perfect material.
But where to find it in black… Im going to ‘Home Depot’
in a minute, I’ll look around for ideas. It is a readily
available material.

I dont know what those kneepads are, but they
are nice cause the thing slides so easy. The medallion
is full of liquid nails, one of those quick fixes that
ends up permanent.

I Think its actually more sturdy this way than with the
diagonals the way they are intended to be used.

If you look even closer at the pic u will see that I made the
top clip, too. Its kinda funny, I must have 15 functional stands,
and I use this one thats all jerry-rigged from spare parts :p

2off my prototypes have cracked, but now i know that the screws need to be replaced too.
The medallion needs to be held on with through screws and nuts, using the existing ones tapping into the medallion has meant that in the opening and closing of the legs my new parts all cracked at the corner, see highlite on pic, notice the lighter streak, thats a minor crack (this actually is visable on the main pictures, I just hadn’t noticed it had already cracked when pic was taken). The lug that the screw taps into cracks away form the main body at both screws.

Basically using the existing screws tapped into the medallion means that the lug where the screws tap into wants to stay sitting on the bracket but the rest of the medallion pushes away and cracks at the corner. I think even with radius in there after a while a similar problem would arise, it might be the threads stripping instead of cracking but the cause is the same. Maybe having longer screws that tap deeper into the main medallion body would help but i think thru screws is the correct way to secure this. By using screws that go thru the medallion and secured with nuts the whole medallion moves slightly when opening/closing legs but as the whole thing moves there are no material stresses generated.
I will keep opening closing legs etc and see if i can spot any stresses etc with the one i have on my stand, I think i have now solved the cracking problem so in theory it should be fine.

i dont get it.
Thats all solid material- that thing should not crack.
Nintendo’s version wasn’t even solid like that,
and it was just regular old black plastic.

Maybe you should make an aluminum
(professional grade) model. Black anodized
would be awesome.

What a frustrating problem 🙁

Hedgetrimmer:

What about the sprung screws idea I mentioned in that PM? That would allow the medallion to move relative to the clamp bracket while preserving the front face and your hilarious logo 😀

True, the cost would be higher, but would a spring be more expensive than a machine screw and (locking) nut? (Maybe harder to source…)

Were I you, I would add the fillet and, if that fails, look into other types of plastic. I’m still not ready to make my PP version, but I’m definitely going to incorporate a fillet or chamfer into my design.

Pocket: Yeah i know solid lump but it cracked, the milling left a sharp internal corner and thats where the crack started, a radius would most likely sort it, but also not having the screws tapped into the plastic has meant that the one i have on now, milled at the same time so it also has the sharp internal corners, is fine and shows no signs of fatigue etc.
I will get the next few done and move the engraving down a little so the through screws don’t foul the writting and als add in a radius around the internal shape to remove the possible fracture points.

Runnerpack: I was gonna put some sprung screws on but couldn’t find any decent springs, so I just attached the new red one with a couple of cap head screws and dome nuts, no washer or springs and it works great.

I will keep on testing and post any relevant results.

If anyone would like my cad drawings for this so you can make your own then PM me and I’ll email you a copy.

 

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