Suggestion on Tool (Horizontal Buffing-grinder)

[BTP]

Guys, I need to buff edges on HDPE table tops.
I do mass production more or less (100 + at a time)

I need to have a setup like a router table that has a buffing wheel.
In other words horizontal.

Do you guys have any suggestions?

[twelchPTM]

if your router has a variable speed controller, I don't see why you couldn't chuck a buffing wheel in the router with the speed turned down...

I have used an industrial heat gun to polish edges on HDPE.

[BTP]

I have used an industrial heat gun to polish edges on HDPE.

will it leave it satin smooth?

[twelchPTM]

heat gun will only "clean up" what is there. Just like flame polishing acrylics, if you can see the tool marks before, you will see them after but they will be clean and less noticeable. If you san the HDPE you can make the tool marks go away but you get a fuzzy almost white edge and a quick pass with the heat gun or a torch will melt the fuzzy and restore the color.

[Brady Watson]

I've never polished HDPE (interesting), but I have buffed plenty of acrylic. I start with 220 on and orbital and work it up to 600 grit (Stockroomsupply.com has grits at least to 600). Then I take a 6" automotive type buffer and buff it with 3M Finesse It, then Novus Step1, then Novus Step2. I do a final cleaning with Novus Step3.

I often need to keep the paper on the plastic to help protect it during transport, so flame polishing is out for those cases. Plus, with a buffer you have all the control in the world and you can rework or back up a few steps if necessary. It doesn't take as long as you'd think to get a really nice polish on the edges using this method. If you have really nice edge cuts you can often skip a few grits to speed things along.

-B

[twelchPTM]

not to be a * but you got your Novus numbers backwards!!

But yes the final appearance of a hand polished edge is far superior then any other method I have ever seen, I have not tried to hand polish the HDPE however perhaps I will give it a try though...

[bleeth]

Back in the old days building boats when at Cigarette Racing Team some of the entrance hatches were ordered with an all Lexan cabin hatch design. After sanding the parts down to a smooth, but matte, finish, we would then go to wet sand. Instead of using water we would use oil (like motor oil) and it would get to a polish as high as the factory faces in relatively short order. All by hand. I wouldn't use this today for a large production run, but if I had just a couple parts to do and didn't already have good polishing compound on hand I would.

[twelchPTM]

did a few test pieces last night, you can get a high gloss super smooth edge with a little bit of buffing but you need to sand out any tool marks really well. I went up to 400 and could still see the "scratches" from the sand paper after buffing.

[BTP]

did a few test pieces last night, you can get a high gloss super smooth edge with a little bit of buffing but you need to sand out any tool marks really well. I went up to 400 and could still see the "scratches" from the sand paper after buffing.

what I have been doing is sanding 80 then 400
Then, running a "polisher attachment" hooked to my drill.
The heat gun did not work for me.
I bought a bench grinder yesterday & am going to try it for a while.
I still am going to try and build a table top buffer, where I can just spin the table edge against the buffer.

My new product.


http://www.talkshopbot.com/forum/attachment.php?attachmentid=18649&stc=1&d=1377115248

[Brady Watson]

not to be a * but you got your Novus numbers backwards!!

Yup...BUT...Logic would seem that Novus got their numbers wrong! :p


I went up to 400 and could still see the "scratches" from the sand paper after buffing.

Did you do it by hand back & forth or use an orbital?

-B

[gerryv]

I'm wondering if a Shopbot air drill attachment with a small diameter buffing tool might work? Does anyone know what the rpm range is? If it worked it would allow you to automate to a degree using your existing tool paths I'm thinking.

[twelchPTM]

Brady - I sanded by hand which I know will leave the scratches more evident then an orbital but using an orbital on such thin edges can get a little wonky.

I imagine a table top edge buffing machine would not be a terribly complicated device, If you start with a buffing machine affixed to a table, you could mount a "lazy Susan" to the table and use suction cups to hold the top, then using a smaller motor with a rubber wheel to spin the top at a set speed. you could even include a swivel mount to hold the compound.

If you wanted to get really fancy you could mount the buffer on a retracting slide and a sander in the same fashion, then the only real work is making sure the table is position correctly on the turntable.

[gundog]

If it were me and I was going to make something I would make a verticle lathe turn the top on a spindle using the mounting points you are using for the base and spin it turning the edge with a high speed steel bit.

I make rollers from UHMW and the finish quality is not up to snuff so I always cut the parts oversize and turn on a manual lathe for a real nice finish. My 2 cents after you make the machine it will turn the parts very fast and results will be close to polishing if the bit is sharp.

Mike

[gundog]

I thought about this overnight and I am wondering why the edge needs to be polished? I cut a lot of Seaboard a type of HDPE and make table tops I don't polish any of the edges. Maybe a new cutter is what you need. I do not get a perfect edge but it is very acceptable in HDPE UHMW is another story.

I run all edges with a round over bit 3/16" on both sides manually after cutting on a manual type router table.

I use a single flute 63 series bit from Onsrud I run my 1/4" bit @ 18,000 RPM and 2.7 to 3 IPS. .250" deep so 2 passes on 1/2". I have cut them in one pass but I get a better edge finish with the 2 passes.

Mike

[gundog]

One thing I found out when working with the Seaboard is to round over all exposed edges if not the exposed sharp edge will get nicked very easy even an 1/8" round over nicks fairly easy 3/16" round over seems to be perfect for me and the stuff I make.

If you go to my web site and view my products page you will see many products made from Seaboard in both black & white all in 1/2".

Mike