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ChipKing
05-03-2011, 04:27 PM
Any suggestions on helping ease the pain on finish polishing machine lines and such out of hardened steel molds?? The old use of stones is quite time consuming and the work pieces are to large to use a small ultrasonic polishers and a super stone. I am looking at larger open areas on the tools but the hands are about ready to fall off.

Any suggestions would be nice.

jetski
07-05-2011, 09:50 PM
I wish I could help you. I try to cut everything as smooth as possible and then send it to a polisher who prefers how I cut the tool to all other customers. I can only tell you start on the harden steel with a coarse stone to get the cutter marks out and all the stone marks go one direction 180 grit or rougher depending on how rough your cuts are. Go to 220 and go 90 degreese to the last 180 grit. Take out all of the 180 marks. Now drop to 320 and go 90 degreese to the 220 and take out all of the 220 marks. Keep going untill your mind goes numb. Sorry for the bad news. This is the way I was taught 30 years ago, and why I send out. I do not have the patients for this. If it has to be better than you could finish with #2 road gravel I send out. Good luck my friend.

ChipKing
07-05-2011, 10:28 PM
I just need to see how our outside people do it. It is just a pain that we can build $200,000 tools but take forever to get it polished when they can do it in a fraction of the time. I am all for letting them do it all the time but logistics get in the way most of the time.....

jetski
07-06-2011, 08:58 AM
I manage a small shop. We build all kinds of molds. Everything from medical to millitary. Some are #1 finish, and some are 220 stone finish or still show cutter marks. Unless you are about a 12 man shop and have 4-6 tools per quarter going through, I would use the outsided polisher. It is what I do and it is the most cost effective for us. We are a 2 man shop, 2 cnc mills, 1 cnc 4 axis edm, 1 manual edm, and a surface grinder. My polisher works as a polisher at a larger molder, and sub contracts at night to several shops in the area. Here is the way I look at it. I am a mold designer and builder, that is what I do best and quickest. He is a polisher that is what he can do best and quickest. What he can do in one hour takes me 3-4 hours, and he charges me less than our hourly shop rate per hour. I go back to designing and cnc cutting and my time is more well spent and get more done all around by sending it to him. Now if he was costing me by not getting done in time, that is a different story. Find a new guy to do the work. Tell him up front why you are looking for a new polisher DELIVERY is most important. Ask to see his work. Let him do a few small pieces (sub-inserts or pins) do see if he is worth a dime or not. You will spend $5-10,000 on an ultrasonic polisher, $30-50,000 on a good polisher (depending on where you live +/-). If you do not have a full time guy in house he will never catch up and be as good as a guy on the outside, where that is all he is doing. Send me a pm and I wiss see if I know of anybody in your area to help. I use to travel all over the U.S. at one time. I will help if I can.

packrat
07-06-2011, 06:34 PM
Back in the olden times we would 'pre-polish' before sending cavities out for heat treat. But your probably talking about hard cut cavities.

ChipKing
07-06-2011, 07:35 PM
"But your probably talking about hard cut cavities."

Yep, after hard machining is what is the pain, but in reality it is all a pain. :violin:

We have been doing a lot of compression molds anymore as the automotive industry dried up - at least our big customer did....and alot more are being hard cut after heat treating. We are good at it (polishing) but our money is in chip making.

Thanks for the input guys. Here is our website if you want a peak at where
I do my thing at. Welcome to Dramco Tool and Die Company - Dramco Tool and Die (http://www.dramcotool.com)


















'

H.A.S.
07-06-2011, 09:06 PM
Any suggestions on helping ease the pain on finish polishing machine lines and such out of hardened steel molds?? The old use of stones is quite time consuming and the work pieces are to large to use a small ultrasonic polishers and a super stone. I am looking at larger open areas on the tools but the hands are about ready to fall off.

Any suggestions would be nice.


I hear what you're saying. Sometimes I wonder how my hands held up as long as they did, polishing those gigantic dies.:o

I ran one shop using those old dinosaurs...3D Keller machines. When we got behind, I'd also have to jump in and do the polishing. All we had then was Foredom flex shafts, stones, and various wheels, felt, Ruby stones, etc.

The only time we had to polish really hard steel, was if someone broke off an endmill, and we had to send it out to be welded, filled in. One guy broke a 3" by 10" endmill, shook up the whole neighborhood.

OK, enough of my 'Old days' ramblings. Other than get in there and doing it, I have no advice.:cool:

Very nice shop and webpage you have there, makes this old boy jealous!

Valimarsbro
07-06-2011, 10:59 PM
Smaller step over (assuming cad 3D programs) reduces cusp heights. Maximum cutter size usage will also help. ARAF IS A COMPANY MAKING CUTTERS FOR YOUR APPLICATION AND THEIR TECH AND ENGINEERING PEOPLE CAN HELP GREATLY! THEY HELPED ME! Good luck!! PS I don't work for them!

jetski
07-07-2011, 08:43 AM
I had forgot to say I do hard cut all the H-13 (48-52 Rockwell c) after heat treat. Our polisher is a good guy so I try to cut the smoothest I possibly can so he never hate what I do. He always says ours are the best finishes of any shop he deals with. Polishers are a special group of people. I am glad to have them around. I have seen some unbelievable things done by the best ones. I saw a mosquito one made out of a piece of p-20 that was roughly 2" x 2" x 2". Veins in the wings detail. I don't have a clue how he did it but it was perfect. Thanks to any polisher out there for making my molds look the best they can!

rusty abe
09-14-2011, 11:42 PM
The hardest in the mold making is in the polishing stage, I think. Even with a small step over there is still to be done to improve the surface appearance. You can check Gesswein for they have a lot of stuff for mirror polishing. Foredom flex shaft is the best in term of price as well as flexibility. The only thing they are lacking is the attachments. When I have to mirror finish a mold, I use a flex shaft and my hand is rested on a support table which can be swung.

tbarker80
11-01-2011, 01:04 PM
I have an ultraform uf5600 ultrasonic polisher for sale on ebay if interested.

originally $5500

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices (http://www.ebay.com/itm/190595093117?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649)

miljnor
11-01-2011, 01:14 PM
how do those things work (ultrasonic polishers)?

tbarker80
11-01-2011, 02:52 PM
Basically the machine creates high frequency waves that are transfered into the hand piece where the stone is attached. That makes the stone move in and out at about 20,000+ strokes per second.

rusty abe
11-01-2011, 11:03 PM
I had a chance to take the ultrasonics tool apart couple months ago. Basically it has a dc coil to make the reciprocating movement, a core with a compression spring is free to slide when the coil is energized (by foot switch), at the end of its travel it hit the switch to cut off the power. And since the spring is now under compression it push back the core on which polishing tool is attached. Hope this help in understanding how it works.

miljnor
11-03-2011, 01:52 PM
Oh, I feel stupid I was thinking some super high tech thing that used sound waves to polish! lol...I guess i read too much sci-fi!

rusty abe
11-04-2011, 10:25 PM
Hi miljnor, don't feel bad about it. That is what this community is for (sharing the information). Cheers.

Geof
11-05-2011, 12:13 AM
Oh, I feel stupid I was thinking some super high tech thing that used sound waves to polish! lol...I guess i read too much sci-fi!

20,000 strokes per second would be 'sound waves' for young guys. It is only ultrasonic for us old guys. :D

miljnor
11-08-2011, 06:49 PM
Hey I'm not old!

Hell I make this **** look Good! =)