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View Full Version : I need a tool to build a tool to build a tool!



Black Forest
12-05-2010, 11:21 AM
I am sure you all have gone down this road!

I need a angle plate for my horizontal mill. 12"X 12" X minimum 1" thick plates.

What would be the best way to build this angle plate? Normally I would cut the plates, square them up on the mill and then weld them together with the braces on the back. Then I would heat it in an oven to 700 plus degrees and let it cool slowly. After that I would bolt it down on the mill and face the two sides.

I then thought maybe I would be better to bolt it together and not weld.

So how would you all build one?

vpt
12-05-2010, 11:24 AM
I'd weld it because I'm a welder.

Evan
12-05-2010, 11:29 AM
I would go to a steel supplier and buy a short piece of channel iron and square that up. It will be very close to start with so the work will be minimal.

winchman
12-05-2010, 12:00 PM
"After that I would bolt it down on the mill and face the two sides."

How would you position a 12" angle plate on the mill table to you could face the entire surface?

Carld
12-05-2010, 12:04 PM
I would make it out of angle iron as I have done in the past. It's fast and easy. Of course, buying one is easier.

MuellerNick
12-05-2010, 12:23 PM
I'd weld it. Then I'd put it into my oven if it would fit. If that oven is too small, I wouldn't stress relief it.
If I would need a precise angle plate, I'd buy a cheap one out of CI and scrape it to my standard (that is very low :D ).


Nick

bborr01
12-05-2010, 12:32 PM
I would go to a steel supplier and buy a short piece of channel iron and square that up. It will be very close to start with so the work will be minimal.

Channel iron?????

Brian

rockrat
12-05-2010, 12:38 PM
It looks as though the replies have it nearly covered. Now you need to decide on what you are trying to accomplish in the end.

Do you need something quick and dirty to just get by? Then weld up a bunch of angle iron and let her rip.

Want something that will give you a few months of light service or a year or so of intermittent service? Order the channel and have at it.

If you want something that will be a tool in your shop that you can use for years? In order - rough cut, weld, anneal, mill, drill, and use.

Sometimes is it hard to decide how to go about making a tool because you haven't decided how much value it should have when you are done. In manufacturing, we did what we had to quickly so as to just get the job done. In tooling, we made things to last and had to invest more time into the project.

What are you willing to invest?
rock~

JCHannum
12-05-2010, 12:38 PM
Structural shapes do not meet the 12" X 12" X 1" thick specs desired, so purchase of angle or channel will not work.

Beyond that, it depends on your resources and desired accuracy. I would prefer the bolted assembly myself as it would probably entail less work than the welded and stress relieved construction and be every bit as accurate and serviceable. With reasonable care in machining the components, final maching of the complete assembly would be minimal if needed at all.

gary350
12-05-2010, 12:49 PM
After you weld them put them in a furnace or fire to relieve the weld stresses. A bag of BBQ charcoal works great so does a pile of unwanted old pallets. After they have been welded and heated to about 1100 degrees and air cooled they are ready to square in the mill.

Black Forest
12-05-2010, 01:21 PM
I really like to weld and I am a much better weldor than machinist! But I think it would be very enjoyable to bolt it together. I try it and let you know.

As to the question regarding how I would mill it after I bolted it to the table. That is easy. It is a horizontal mill. I would let it hang over the table on the spindle side and have at it. Easy to do with a six inch face mill.

dockrat
12-05-2010, 01:26 PM
Don't forget......we require pictures as you progress :)

Evan
12-05-2010, 01:35 PM
Structural shapes do not meet the 12" X 12" X 1" thick specs desired, so purchase of angle or channel will not work.


If you buy the right grade they do. Angle is available in 8x8 and larger in 1" thickness. Channel is rated by weight per foot and is available in 12" depth at 30 to 50 lbs per foot.

Toolguy
12-05-2010, 02:53 PM
Bolted joints can move, even with dowel pins. If you bolt it, put some heavy tack welds every couple of inches at the joint. An angle brace or two will help keep it square over time.

JCHannum
12-05-2010, 03:17 PM
If you buy the right grade they do. Angle is available in 8x8 and larger in 1" thickness. Channel is rated by weight per foot and is available in 12" depth at 30 to 50 lbs per foot.

No standard 12" channel has a 1" web. The largest standard heavy angle is 8" X 8" x 1", again, not what was wanted. Good luck with buying a foot of either shape.

doctor demo
12-05-2010, 03:22 PM
If you buy the right grade they do. Angle is available in 8x8 and larger in 1" thickness. Channel is rated by weight per foot and is available in 12" depth at 30 to 50 lbs per foot.
I have some 4''X8''X1'' angle in 8'' lengths that came from Caltrans when I demoed some bridge rail testing mock ups prior to the final design for the new Oakland Bay Bridge . If I would have been thinking I'd have kept more than a couple of them:)


Steve

lane
12-05-2010, 03:44 PM
I would just buy a nice cast iron one. they are cheap . check Enco.

darryl
12-05-2010, 09:27 PM
I haven't progressed to welding (yet), so I'd bolt it. I would still bolt even if welding was going to happen as well.

My procedure would be firstly to acquire the plates in the right dimensions (obviously), but then carefully mount and face one side of each. Then machine the important edges, one where the other plate butts up to, the other where the edge would sit against the table, and also the strip opposite the faced side where it will butt up to the base piece. Drill, tap, and recess for socket head bolts.

I'd assemble using a high grade epoxy as gap filler, making sure it goes into the bolt holes and threads as it's squeezing out. The bolts would be snugged up during the epoxy squeezing process, but not overtightened. If the edge machining was done properly, the pieces should be able to bolt together in alignment beforehand, but I'd be using some 456 blocks to help maintain squareness during the bolting and epoxying process. Pins can be added later, or you can consider that the bolts ARE the pins- being filled with epoxy, there won't be any room for things to shift. As far as the bolts go, you can usually tighten them a bit more once the epoxy has cured. I know this means that the bolts have to break free of the epoxy surrounding them, but that's ok- there's still a zero gap there, so no play would be allowed. The epoxy is used only as a filler, and being in compression it will not release the pieces, even if it doesn't stick that well to the metal. But a decent grade will stick to the metal anyway. PC-7 would be good for this. JB might be good also, but I'd stay away from fast setting formulations, and paying some attention to low shrinkage formulations.

This is how I'd do it regardless, even if I could weld. I find that a bolted structure, if properly prepared beforehand, can be quite true without further machining after the fact. In this case, since the plates are relatively large, I'd be adding braces, using the same construction method. I wouldn't be bothering to face the mating surfaces beforehand for the braces, just making sure that squareness is maintained while the epoxy sets. Again, those bolts can be further tweaked after cure.

Carld
12-05-2010, 10:59 PM
Just break down and buy an angle plate. It's going to be a bugger to weld and straighten and bolting it together is a joke.

Look here http://www.use-enco.com/CGI/INPDFF?PMPAGE=462&PMCTLG=00

Your going to spend more for metal and time that an angle plate will cost.

rockrat
12-06-2010, 11:39 AM
Just break down and buy an angle plate.

Not a bad point but it still all depends. Black Forest may only need a "get me by" piece of tooling. He is the only one that can decide what he really needs. The way I read the post it sounded as though he was looking for multiple ideas so that he could make a decision on what would work for him.

I will contend that I have made dozens of jigs and fixtures from garbage sitting around the shop. They did what they were intended to do.

One of the best instructors that I had in college was a "hill billy" looking fellow that probably has forgotten more than I know. He had a hard time getting kids to understand that not everything has to be perfect and to have a good design means that the designer thought through to the goal. If it is a one shot deal where close is good enough, you have the scrap sitting around and money is an issue, then weld or bolt it together. If you need the precision and dont have the time to assemble what you need then by all means as you noted, make a purchase and keep moving.

rock~

JCHannum
12-06-2010, 01:24 PM
ENCO prices are of little use to Black Forest as he is in Germany. There is no reason that a bolted and gusseted or welded angle plate will not be sufficient for any home shop application.

I have seen many shop fabricated angle plates, in both bolted and welded construction in use in commercial shops. The economics all boil down to cost and availability of materials and cost of shop time. Making tooling during idle shop time is a good trade off to save on the cost of buying new, particularly if the tooling is not readily available. Even more savings is realized if drops or surplus materials are available for fabrication.

The ENCO 12" x 12" x 12" unground plate is $170 plus shipping on 104#. I suspect a talented scrounger and fabricator can beat that cost handily.

Rosco-P
12-06-2010, 01:48 PM
I'd look for a machine shop auction and pick one up that way. Maybe Ebay, here's a 10x8" http://cgi.ebay.com/NEW-ANGLE-PLATE-HEAVY-10-x-8-/230559924046?pt=BI_Tool_Work_Holding&hash=item35ae713f4e or here http://cgi.ebay.com/12-x-12-x-12-ANGLE-PLATE-NEW-TOOLING-/230531463369?pt=LH_DefaultDomain_0&hash=item35acbef8c9

Sorry, failed to notice your location. German Ebay maybe?

bob_s
12-06-2010, 03:41 PM
Check with a local steel supplier for a 1 foot drop of H-section then just lop off 2 of the legs and you're close.

Check for HEM300
at http://www.masteel.co.uk/continental_channels_h_sctns.htm

web is a little light at 21 mm, but the arms are 39 mm

Black Forest
12-07-2010, 05:41 PM
I welded up a angle plate today. It is cooling overnight. Tomorrow I will mill the surfaces and take pictures. I just used what I had available on hand.

Toolguy
12-07-2010, 05:44 PM
Most likely that one will be just fine.:)

Black Forest
12-09-2010, 04:42 PM
The angle plate that I made from on hand materials did not come out very good.

So I went today and bought steel for a new one. It will be a 12" X12" X 12" out of 1.250" thick steel. I will bolt it together first and then see if I will weld it also.
http://i853.photobucket.com/albums/ab91/burnandreturn/angleplate120.jpg

oldtiffie
12-09-2010, 05:24 PM
I made a pair small angle plates for my shop engine hoist front castors not so long ago. All out of HR ("black") MS bar. I didn't worry at all about the band-sawn faces - just dressed them up with and angle grinder and belt sander.

I had decided to see how close I could get without machining but it didn't matter anyway.

I was very fussy about the fit-up and the weld tack and run sequences. I dressed it up with the angle grinder and then put a good square over it. It would have only needed a skim cut on the mill or the surface grinder to have it in good shape.

http://i200.photobucket.com/albums/aa294/oldtiffie/Hydraulics/Hyd-lift1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Hydraulics/Hyd-lift2.jpg

Angle plates don't need a lot of bulk or strength but they do need a lot of stiffness.

I do a lot of fabrication for job set-ups and tack-welding or "stitch" or "hit and miss" welds - light passes are often all that it needed. If I see a need for it or them I keep them otherwise I cut them up and put them in the rack/storage or just "bin" the parts and send them to scrap.

One of my projects in the hopefully not too distant future will be a light weight but stiff tack-welded angle plate type fixture for my 11" shaper to extend the distance that I can mount my rotary table from the shaper itself. This is so that I can fit a bigger face-plate or a 3-jaw chuck with a job sticking out of it that I can machine some internal slots/key-ways/splines and the same externally. It will also allow me to "prop" or brace the rotary table from the back/rear as most rotary tables are weak where there is an axial thrust load. The "end game" is not so much to have the angle-plate "really accurate" over-all but to have the rotary table vertical and vertical to the shaper table and square to the ram axis.

If there are any errors, I'd either angle-grind them off or weld-fill and grind them off. Its surprising how accurate you can be with an angle-grinder if you are careful. I'd perhaps finish it off on the mill or grinder or preferably the shaper.

It is also surprising how distortion can be limited or corrected by minimal welding and correct clamping/set-up and welding sequences.

Strategically placed struts can make a huge difference and allow for much lighter but quite adequately stiff jobs.

My stuff is only as good as needed - not more - and I don't embellish anything if I can help it. But it has to do the job - the rest doesn't matter.

Black Forest
12-10-2010, 02:04 AM
I am actually building a 90 degree table for my horizontal mill. Whereas I don't have a vertical mill yet. But sometimes I need to mill something that I can not do on my horizontal mill. So I am building a table that I can use my horizontal mill like a vertical mill. It is not a great solution as it is difficult to see the work but until the vertical mill is installed I need this solution. Hence why I am building it so rigid.

boslab
12-10-2010, 02:21 AM
Detracting a little but still a usefull tip if you have the misfortune to own a bigish vertical miller, angle plate required, i found that an old engine block serves well as a do all fixture, you can face one side and use the top, you can drill and tap wherever you feel like with impunity, drop odd shaped lumps down the pots, drill straigh through it with indifference!, ali blocks are quite light too
mark

Black Forest
12-10-2010, 07:54 AM
I squared up the places for the two big pieces of the angle. Then I sat the one on the other and welded the ends on the sides to hold them together so I could drill the holes that I will use to fasten the two together. Did five holes on my horizontal mill. All went really well until the last hole. I had 3 mm to go to reach my depth of 60 mm. Bam! drill breaks off in the hole and the head of the chuck breaks off the Morse taper. On this chuck the Morse taper is an intregal part of the body of the chuck.

I called Albrecht here in Germany and they are sending me a replacement. The service tech told me he had never heard of one doing that. This chuck is the stronger type with a the taper full where it joins the main body.

jkilroy
12-10-2010, 10:52 PM
What in the world do you need 60mm (> 2") of hole depth for? Not for bolts I hope? The general rule is 1.5 x bolt diameter, so even with a 19mm bolt (3/4") bolt you would be looking at no more than 24mm.

Black Forest
12-11-2010, 03:19 AM
What in the world do you need 60mm (> 2") of hole depth for? Not for bolts I hope? The general rule is 1.5 x bolt diameter, so even with a 19mm bolt (3/4") bolt you would be looking at no more than 24mm.

Ah Grasshopper. Each plate is 30mm thick. I drilled both plates at the same time so my fit would be exact. So the first 30mm is not for threads. The next 30mm would be threaded to 22mm with extra depth for the tap clearance and chips. The threading I did after I took the plates apart.

jkilroy
12-11-2010, 02:51 PM
Whew, thats good news. Did you manage to get the broken bit out of the last hole? Are you drilling one side to match the T slot spacing on your mill table?

Black Forest
12-11-2010, 03:45 PM
Did not have much time today to work on this but made a little progress. Once I cut the welds that held the two pieces together the broken drill bit just fell out of the hole. That was a big relief to not have to drill it out with a carbide drill.

I got the braces machined. I will drill it so I can mount a vise on the braces in order to champfer edges or mill 45 degree whatever.

The red rattle can of paint is just for perspective on the mass of this table. It is very very heavy!

Yes I will drill the base to fit the T-slots on the mill table.
http://i853.photobucket.com/albums/ab91/burnandreturn/11-12-10_2025.jpg
http://i853.photobucket.com/albums/ab91/burnandreturn/11-12-10_2024.jpg