Cutting 6061 aluminum W/prs standard/with router

[hunterland]

I have a request from a friend to cut three sheets of 6061 24 x 48 1/4 inch aluminum plate they need 465 holes per plate. they need to hold 1.030- 1.035 tolerance. Is this doable with proper settings or is this just asking for troubles and headaches? any help would be appreciated. Thanks Don Hunter Hunterland Wood Works!

[richards]

That is a lot of holes. When I drill holes in aluminum, I usually just spot drill the hole and then use a drill press or a hand drill to drill the actual hole.

My spindle does not have the proper thrust bearings for drilling. The PDS Colombo web site advises ramping into a cut rather than plunging.

[Brady Watson]

It is doable, but not easy. Holding 0.005" tolerance on AL with a Standard and router is a challenge & you need a very tight well tuned machine to do it, in addition to well thought out toolpaths. I would try cutting say, 4 holes and check your tolerance. Sometimes you can tweak the toolpath/vectors to compensate for over/under sized parts if they are consistent between parts. Be sure to use a spiral ramp into the material when you cut.

-B

[blackhawk]

A lot of holes indeed, you are going to have almost half the sheet turned into chips! I think that you have a few things to consider. You can drill the holes with a 1-1/32 drill bit with a turned down shank or you could circle mill the holes with a 1/2" endmill. You also need to think about cooling, especially for the endmill. Chip collection could be an issue. That is a pretty tight tolerance for the hole diameter. That alone would make me nervous. You could easily dial this in for a single hole, just not sure how well the Shopbot would do over the course of 465 holes. Is there a tight tolerance from hole to hole? If the hole tolerance absolutely has to be held for every single hole, I would pass on such a job. You have to ask also if they expect you to measure every single hole to confirm accuracy. If you make one hole .001" oversize, do you have to scrap the entire plate?

[bearcat]

From a precision measurement perspective I would ask these questions. What tool(s) will be used to do the final acceptance measurements? How is it calibrated, and to what tolerance?

Ed

[waynelocke]

Won't waterjets hold those tolerances?

If so, get a price for waterjetting and sub it out.

[hunterland]

Thanks everyone for the advice. I have been wanting too cut aluminum but on a much smaller trial setting. Also I,m not sure of the payment as it is a bid job through my friend. I emailed him some of the questions that you all posed, and have not heard back, my concern was weather it would do damage to the shop bot? Thanks again! Don