^ forget what it is in the mic - 6 but after alkaline etch the surface is smutty, hence you then acid etch it to get rid of that (magnesium??) and rinse then anodize, so long as the part is kept wet bettwen etch and acid etch your fine, don't let it dry, just etch, rinse acid desmutt and anodize, if you desmut with sulpheric, you only need a quick rinse prior to anodize.
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Largest Manufacturing Technology Community on the Web
Stay Connected:
Milling a large 6061 plate FLAT
- Thread starter CNCBurnout
- Start date
- Replies 38
- Views 9,731
SteveBausch
Stainless
- Joined
- Jan 11, 2010
- Location
- Indianapolis
Optimist says the glass is half full
Pessimist says glass is half empty
Engineer says glass is wrong size
In the current situation, the Internet says “use MIC-6 tooling plate”
The material supplier can usually have it done for you. As far as Blanchard grinding aluminum? It is done everyday without a problem.
WILLEO6709
Diamond
- Joined
- Nov 6, 2001
- Location
- WAPELLO, IA USA
can the end customer inspect to that? If they can't, make it work and sell them some sunshine on the cert for the job. On some jobs it will matter- on some you'll put enough extra weight with the rest of your stuff on it to bend it more than 0.005 inches in 48....and I have seen a lot of jobs that size where even 0.035 is workable function, but your customer pays the bill.
garyhlucas
Stainless
- Joined
- Oct 17, 2013
- Location
- New Jersey
A vendor used to advertise double disk grinding, both sides at the same time. Don't remember who it was though. Seem like that would be the best way.
Dan from Oakland
Titanium
- Joined
- Sep 15, 2005
- Location
- Oakland, CA
You are being told by multiple people here with more than a few years experience that you are going to have a heck of a time keeping that thing flat to even double what the gods are asking for. Mic-6 or other cast jig plate is your best bet of meeting their requirements. As soon as you touch the surface of that plate, its going to start to move and you will chase the curl until you're out of tolerance on the thickness. Then you can try it on a 2nd piece hoping to get lucky this time. How much is the material worth ? Just because you have it in stock, is a poor reason to proceed.
Perhaps after you have scrapped two pieces of material the gods will reconsider their foolishness. Good luck!
Perhaps after you have scrapped two pieces of material the gods will reconsider their foolishness. Good luck!
HuFlungDung
Diamond
- Joined
- Jan 19, 2005
- Location
- Canada
I milled a 14 x 30" x 1.25" T6061 plate to within a couple of thou of parallel. I did not have any major curl of the plate, but I didn't have any actual thickness spec to hit. The biggest headache with milling large plates near the limits of machine travel is getting the cutter clear of the work on exit so there is no back side cutter shaving going on, which results in a permanent ledge.
Extruded brass has to be the worst thing ever: cut the skin off and it bows back and forth like crazy.
Extruded brass has to be the worst thing ever: cut the skin off and it bows back and forth like crazy.
LKeithR
Stainless
- Joined
- Sep 1, 2011
- Location
- Langley, B.C.
In my experience the engineer almost always specifies a glass size and/or style that is not available as a stock item...
Job Shopper TN
Cast Iron
- Joined
- May 17, 2015
- Location
- Southeast TN
I would try double-sided tape. We have had good results with that. I do not know the brand but it is blue, pretty thin tape - may be Scotch brand. It will take a lot of careful cleaning and stoning and re-cleaning, but that's what I would try. Use a good free-cutting tool and no coolant, a light spray of WD 40 without hitting the tape... Go fer it.
I will add this - if this plate has holes for bolts (or can be added if this is an in-house deal), like others have said, bolt it to another plate or the table through those holes and face it flat while bolted down. Then when it is bolted down to wherever it goes, it will be in approximately the same state - unless what it bolts to ain't flat...
I will add this - if this plate has holes for bolts (or can be added if this is an in-house deal), like others have said, bolt it to another plate or the table through those holes and face it flat while bolted down. Then when it is bolted down to wherever it goes, it will be in approximately the same state - unless what it bolts to ain't flat...
Miguels244
Diamond
- Joined
- Mar 27, 2011
- Location
- Denver, CO USA
Exactly.
Better yet buy some mic6 tooling plate.
It's what that material is for.
Bellinghamster
Plastic
- Joined
- Apr 5, 2015
- Location
- Bellingham
I run a seismic test lab and use similar 6061 T6 plates as sacrificial adapter - drilled and counterbored to match my servo-hydraulic shake table mounting pattern, then drilled/tapped and threaded inserts for whatever I need to bolt down (7ft tall 3500lb telecom battery racks and such). The adapter plates must be very flat, since the shaker table is on oil film bearings with only .010 clearance (4x6 slip table). Twisting the table by bolting down a warped plate can/will cause bearing drag/damage and ruin my day.
I finally came up with an easy and inexpensive method that doesn't require machining or grinding. I level the plate supported on jackscrews, run masking tape around the edge to make a dam and pour ~3/16" deep thin epoxy (bar top coating seems to work very well). Let gravity level it and it's flatness ends up matching the curvature of the earth.
You might talk to your customer and see if they'd be willing to accept something similar if the application can tolerate it.
I finally came up with an easy and inexpensive method that doesn't require machining or grinding. I level the plate supported on jackscrews, run masking tape around the edge to make a dam and pour ~3/16" deep thin epoxy (bar top coating seems to work very well). Let gravity level it and it's flatness ends up matching the curvature of the earth.
You might talk to your customer and see if they'd be willing to accept something similar if the application can tolerate it.
UncleFrank
Cast Iron
- Joined
- Nov 14, 2015
- Location
- Midwest, USA
We had good luck doing similar. We used 605 resin for the filler as I recall. Clean the materials with acetone, etc and use a release agent on both pieces to make getting the material off the sacrificial plate easier and easier to clean the 605 off the sacrificial plate for the second side if you have to flip more than once.
Tooling plate is the way you want to go, if you can.
epoxy is a good idea. but i would spray release agent deliberately on and let it level. sikafloor 156 is cheap and does the job, you dont need any fancy, uv stabilised epoxy. then clamp it to the table and true it up on the other side. peel the epoxy off and done.
CNCBurnout
Plastic
- Joined
- Oct 6, 2017
Well I finished the plate and got it within .003" flat and parallel. It was 1.5" thick 6061 t6 aluminum that I cut roughly .05" a side flipping it 4 times. I roughed out the 8 larger holes. Then on my last two passes I faced .012", drilled, tapped and holemilled dowel holes, flipped, finished the larger holes, then faced the last .012"
You can see my setup in the pictures. Made counterbore holes so I can bolt the part down to three points. I used 3 jack screws to dampen the part.
So my final thoughts, yea it took me longer then a Blanchard grinder but I was able to do it. I think it wouldve been much easy if I could've used T0 or the MIC-6 Aluminium.
Sent from my SM-G950U using Tapatalk
You can see my setup in the pictures. Made counterbore holes so I can bolt the part down to three points. I used 3 jack screws to dampen the part.
So my final thoughts, yea it took me longer then a Blanchard grinder but I was able to do it. I think it wouldve been much easy if I could've used T0 or the MIC-6 Aluminium.
Sent from my SM-G950U using Tapatalk
Larry Dickman
Titanium
- Joined
- Jan 30, 2014
- Location
- Temecula, Ca
glad to see it worked out. Where did you get the jacks? Home made?
CNCBurnout
Plastic
- Joined
- Oct 6, 2017
No they are eBay scores, would be a good home project though
Sent from my SM-G950U using Tapatalk
Ries
Diamond
- Joined
- Mar 15, 2004
- Location
- Edison Washington USA
Next time, order it already flat from these guys.
TCI Precision Metals - Machine-Ready Blanks and Contract Machining
I used to buy some aluminum from them- it was always right.
TCI Precision Metals - Machine-Ready Blanks and Contract Machining
I used to buy some aluminum from them- it was always right.
I have never seen or heard of a DD grinder that would handle a 24 x 40 plate. Blanchard is the way to do it and it can usually be handled by the supplier. As far as Mic 6 plate (or equivalant)it is not structurally close to 6061 T6. It is very soft and gummy. YMMV
