Hey gang I'm making some parts out of delrin; they've got fins on 'em and when they're cut to length the fuzz is everywhere! I'm thinking of using m y brass tumbler with walnut shells unless someone's got a better idea. Here 's a link to the problem:
Ouch! I normally just use a deburring tool or pocket knife, but that'd be a pia on those. I'd guess the tumbler won't do it, but it doesn't hurt to try.
Walnut shells might work. If they don't then tumbling with abrasive media and water will. I have deburred acetal plastics, both Delrin and Acetron, in one of my vibratory tumblers. I used trianglar and cylindrical abrasive shapes. The only problem is that the plastic will get a matt finish. For your eventual use I don't think that will really be a problem. Even walnut shells, if they can remove the burrs, will give you a matt finish. You can tumble the parts after deburring with polish but it takes a very long time, in my experience, to polish acetal plastics in a vibratory tumbler. You might want to try an abrasive filled nylon brush first to remove the majority of the burrs first. I have had good luck doing this. It is easy to melt the plastic if a light touch isn't used though. Even brass wire brushes tend to be too aggressive. Eric
when they're cut to length the fuzz is everywhere! I'm thinking of using m y brass tumbler with walnut shells unless someone's got a better idea. Here 's a link to the problem:
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Looking at the picture. it looks like the fuzz in one one side. So I am g uessing the parts were cut off on a table saw.
So maybe you could rotate the part as it is being cut off so less fuzz in c reated. So the saw blade in always cutting into the part. Bad description , but I can not think of a better way to describe it.
You might also try a different saw blade or maybe a brand new one.
nd when they're cut to length the fuzz is everywhere! I'm thinking of using my brass tumbler with walnut shells unless someone's got a better idea. He re's a link to the problem:
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guessing the parts were cut off on a table saw.
created. So the saw blade in always cutting into the part. Bad descripti on, but I can not think of a better way to describe it.
Actually I cut 'em with a wet abrasive cutoff saw, as it had the thinnest b lade and so wastes the least material. I'm going to try again with a cold s aw tomorrow. I've also now got access to a 100w laser cutter and we're goin g to take a whack at cutting the parts out of plate instead of whittling ro und bar. Laser means no fuzz at all and that may wind up being the winner.
Thanks for that; matte finish not a problem; after deburring there will be a couple more operations so matte finish will be removed during that machining.
--Actually waterjet would probably be awesome but it's expensive. OTOH our hacker space just got that big laser and, after learning how to use it, I can walk in any time and knock 'em out with that.
On Wednesday, October 12, 2016 at 10:08:45 PM UTC-4, SteamboatEd Haas wrote :
blade and so wastes the least material. I'm going to try again with a cold saw tomorrow. I've also now got access to a 100w laser cutter and we're go ing to take a whack at cutting the parts out of plate instead of whittling round bar. Laser means no fuzz at all and that may wind up being the winner .
I thought table saw because that is what I would use on plastic. So you mi ght try a table saw. I think a sharp blade would produce less fuzz than an abrasive saw. It might be cheaper to use a somewhat thicker blade if it eliminates the fuzz problem. If you are making several thousand parts , it would be worth trying many ways to cut the parts. One advantage of the ta ble saw is that it can be very fast if you set up a stop for length.
Watch out cutting plastics with a laser. The toxic smoke is a serious problem with many plastics (I don't know which ones, but you could find out).
I wrote an article about a shop in CA that does that, on weekends only, with only the owner in the shop, and he opens all the windows and wears a SCUBA rig when he does so.
Damn, I spelled matt, er, matte, wrong again. If you decide to cut with a laser be aware that Delrin, an acetal plastic, will give off formaldehyde ( I spelled that right at least). Not only is formaldehyde a lung irritant and poison it also is corrosive to certain metals, most iron alloys being among them. So make sure the laser cutting operation is well vented away from people and other living things. Eric
They look pretty small, even a quick twist against a sanding machine might do the trick. Spin it around and repeat. Might be a couple seconds a piece if you can find the grit that will cut that stuff off.
That's some serious machine time. Are you milling lengths, then cutting to width? No, judging by the burrs, you're not, are you? Which begs the Q: Why not?
Yeah, 6-up on your driveway and hit 'em with the weed burner at regular walking speed. You'll be done in no time.
I've cut acrylic and polycarbonate with a triple chip blade that came out very clean. Blade wasn't cheap. Have you talked to a plastic supply house? Maybe they can advise.
Not as far as I know. I saw one cutting shapes out of 1-inch UHMW, which has produced lots of fuzzy burrs when I've cut it, and it came out clean with the waterjet.
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