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View Full Version : Mill work holding clamps (home made ?)



Alistair Hosie
01-03-2006, 10:19 AM
I would like some of the clamps that hold the work on the edge as opposed to the top clamping fixtures we know and love. I have seen commercial offset clamps that work on a cam system and fix to the side of metal sheets, etc. and hold very well. My idea is to leave the top surface completely free for flycutting, etc.I wonder if anyone has made these or others at home they don't look too difficult. Perhaps someone has their own designs please show or explain them as I am keen to do this as a small project. Why you ask answer because they seem prohibitively expensive to buy for what they are. Alistair

Dawai
01-03-2006, 10:28 AM
I took some one inch cylinders (2..) and took three pieces of angle, two anchors ends, other was the second vise, all were bolted to t-nuts.

As the part was laid on the table you applied air, the sliding angle went forward to the plate *drilling multiple holes/slotting, held off bed on plywood scrap.. I tightened the sliding angle each time.

Sorry for the poor description, I have no pictures. MY CNC, it is fast, setup and re-zeroing something too large for the vise is not. You'll see pencil marks on the bed when something has to be repeated.. yeah.. that's me, hillbilly..

Wedges would work equally well.

I have saw people on the net use two sided tape.. yeah.. right.. I broke two or three cutters putting the hp into the work..

jkilroy
01-03-2006, 10:29 AM
I agree, unless you are buying questionable chicom soft metal junk, strap clamps, or milling clamps, or whatever you want to call them, are darned expensive. I'd expect that a lot of this is due to the fact that many of them are forged.

aboard_epsilon
01-03-2006, 10:56 AM
http://cgi.ebay.co.uk/Carver-Edge-Grip-Vices-Milling-Drilling-Clamp-Vice_W0QQitemZ7577061866QQcategoryZ12584QQssPageNa meZWDVWQQrdZ1QQcmdZViewItem

all the best...mark

PTSideshow
01-03-2006, 11:24 AM
Have seen some of the double sided tape used for clamps for sheet goods. they do make different holding power ( in pounds it will hold up) on the tape also the thin foam tape that is used to hold the badges and trim on the cars comes in various strenghts. 3M is the biggest maker of differing grades of the tape products. I got some sample rolls from them when I was at a sign biz show years ago. If you go to the auto parts/paint store to get the foam tape they probally will have a 3M catalog. To make rewmoving the foam tape easier use a hair dryer or heat gun.
I have wondered if you could hot glue the sheet goods to something thicker and clamp against that. You can also get hot glues in differening streghts of hold power. You may have seen the dent puller on TV. And now for something completely different.
http://i35.photobucket.com/albums/d200/ptsideshow/DSC01641.jpg
http://i35.photobucket.com/albums/d200/ptsideshow/DSC01638.jpg These are printer equipment from the letterpress days used for clamping the loose type cuts and borders in place for printing.
http://i35.photobucket.com/albums/d200/ptsideshow/DSC01642.jpg
http://i35.photobucket.com/albums/d200/ptsideshow/DSC01643.jpg
The items come in handy if you can find them for bars to lift up and level work or the clamps. on different machines. the printers furniture as came in hardwood which was used for the same purpose.
You can find it at fleamarkets some times they like the old type trays called type cases. You can also check Leev valley tools for ideas on clamping wonder is the vacuum table would work.
http://www.leevalley.com/home/main.asp


------------------
Glen
Been there, probally broke it doing that

[This message has been edited by PTSideshow (edited 01-03-2006).]

[This message has been edited by PTSideshow (edited 01-03-2006).]

Mike Burdick
01-03-2006, 12:13 PM
Alistair,

Okay, you said “homemade” and “inexpensive”! I made some and they worked fairly well but have only used them a couple of times and don’t know the longevity of them. Anyway…

Example for T-nuts that are for a 9/16 - inch bolt: I used some 9/16 X 1 inch socket head cap screws and machined the side of the bolt head so that it had about 0.010 inch eccentric. Any more than that would have weakened the socket part of the bolt and also would have made too much of a cam angle so that it could vibrate loose when machining. I then machined a brass “washer” that was smaller than the bolt head and about 1/8 – inch thick - placed on the bolt between the head and the table. This was used because as the bolt is tightened for the “cam” action it will “crush” a bit and hold the cam in place. You’ll have to have extra brass washers because they will eventually crush beyond the bolt head and be in the way. Also, the bolts must be threaded all the way to the head. Remember to have the bolt threads short enough such that when they are tightened they don’t go thru the T-nut as this can easily break the T-slot in your table.

If the head of the bolt is too high, you can also machine off the top as long as you have enough left for the allen wrench to hold.

Cost? About $0.25 each! Is that cheap enough for you? http://bbs.homeshopmachinist.net//wink.gif

Mike

____________________



[This message has been edited by Mike Burdick (edited 01-03-2006).]

Alistair Hosie
01-03-2006, 01:09 PM
Where the heck will ah get twuntie five cents mister ahm Scottish di yeh no ken, seriously looking good thanks bud.Alistair

lbender
01-03-2006, 01:21 PM
Allistar,

Here is a clamp that allows full access made from scrap aluminum plate. The plates are held to the mill table by T-nuts and studs. The socket head screw angles down very slightly to help prevent the work from lifting off the table. The end of the screw does leave a mark in the work piece, but not too bad, certainly commenserate with the price.

http://i25.photobucket.com/albums/c51/lbender/000_0337.jpg

Norman Atkinson
01-03-2006, 02:18 PM
Tubal Cain,
Thin piece vice from Simple Workshop Devices.

Yes, Brother Alistair, it's that man again.

Norm

Alistair Hosie
01-03-2006, 02:42 PM
Ibender that's a good design could you not put slight packing strips between the nut end and the workpiece to prevent marking?Alistair

lbender
01-03-2006, 04:40 PM
Alistar,

Yes, you can put a packing piece between the end of the screw and the work. This eliminates the damage to the work with an increase in the chance the work will lift off the table. I have used this setup both with and without packing depending on my tolerance for the ding in the side of the work piece.

Allan Waterfall
01-03-2006, 05:00 PM
Alistair,

If you've got any books on using a shaper you'll probably find what you are looking for in there.

Basically you need something that is putting a sideways and downward force onto the workpiece,

Allan

Your Old Dog
01-03-2006, 05:05 PM
<font face="Verdana, Arial" size="2">Originally posted by lbender:
Alistar,

Yes, you can put a packing piece between the end of the screw and the work. This eliminates the damage to the work with an increase in the chance the work will lift off the table. I have used this setup both with and without packing depending on my tolerance for the ding in the side of the work piece.</font>

When I used to pull barrels off firearms using bored hardwood blocks, I used lead sheet as a packing. Occasionally I'd put some violin players rosin powder on the lead to make sure thing didn't slip and scratch the blueing. If you try that you must first clean everyting with alcholol for firm grip.

For my wood working, I clamped a buttress board to the opposite side of my workbench to position the wood I was working on. Then I made a cam/paddle, drilled a hole thru it and my workbench and was able to cam actuate the thing when sanding, dovetailing and carving. I trapped the piece I was working on between the cam and the buttress board. It was a great time saver. No reason such a cam couldn't be incorporated into the setup that Ibender has going for him In the pictured post above.

Let us know what you come up with.

Your Old Dog
01-03-2006, 05:14 PM
How about this one Alistair?

http://images.google.com/imgres?imgurl=http://www.thefaro.com/PageMill_Resources/clampat.jpg&imgrefurl=http://www.thefaro.com/tripatent.html&h=360&w=252&sz=20&tbnid=xvG2-ChM_i QJ:&tbnh=117&tbnw=81&hl=en&start=40&prev=/images%3Fq%3Dcam%2Boperated%26start%3D20%26svnum%3 D10%26hl%3Den%26lr%3D%26sa%3DN

edited to add:
looks like you'll have to cut and paste it to the address box in your browser. Even with the . . show as a link.

[This message has been edited by Your Old Dog (edited 01-03-2006).]

edited to further add:

What the hell? It's working!

[This message has been edited by Your Old Dog (edited 01-03-2006).]

[This message has been edited by Your Old Dog (edited 01-03-2006).]

J. R. Williams
01-03-2006, 05:25 PM
Alistair
Check out the "Home Metal Shop Club" web site and go to the May 2002 newsletter. I have an article on a set of T Slot clamps I fabricated using hex nuts and socket head screws with an eccentric head.
J. R. Williams

BillB
01-03-2006, 05:38 PM
J.R.,

If that's the article I remember on making "Mitee-Bite" type clamps, the dimensions are all wrong. The key is to use button-head cap screws (head is too small to cut offset otherwise--ask me how I know this) and to make a simple fixture (rod with offset hole) to turn the heads eccentric. I forget what size hex nut to use for the clamp. Use brass or Al hex stock instead to avoid marring.

BillB

mochinist
01-03-2006, 05:41 PM
<font face="Verdana, Arial" size="2">Originally posted by Alistair Hosie:
Ibender that's a good design could you not put slight packing strips between the nut end and the workpiece to prevent marking?Alistair</font>

Alistair you may like these also, it is kind of a different take on what Ibender did up above. They would be really easy to make too, I have some at work that were bought from J&L industrial and they work great.MITEE-BITE T-SLOT CLAMP (http://www.jlindustrial.com/catalog/product.jsp?id=MTB-10424A&origin=SEARCH:KEYWORD&backtosearchpage=Y) http://www.jlindustrial.com/web_graphic_large/product/m/mt/MTB-10424.jpg
You move the t-slot clamp up close to the part to be clamped, and tighten the screw that wedges it into the t-slot. The other screw with the goldnut on top is tightened. The screw on top has been turned off center, so it is like a cam, it presses against the nut on top and holds the work pretty damn securely. It will ding aluminum, so it is wise to put a piece of scrap in between.

J. R. Williams
01-03-2006, 07:22 PM
Bill B
I used standard SHCS for the project and have no problem. I used a shim under the screw to offset the screws in a three jaw chuck. They are very similar to the commercial units.

JRW

Alistair Hosie
01-03-2006, 11:01 PM
The problem with the ones bought comercially are they are so damned expensive for an occasinal hobbiest user like me who will use these a few times if that a year.Alistair p.s sorry guys could not get those two sites to open

mochinist
01-04-2006, 05:25 PM
<font face="Verdana, Arial" size="2">Originally posted by Alistair Hosie:
The problem with the ones bought comercially are they are so damned expensive for an occasinal hobbiest user like me who will use these a few times if that a year.Alistair p.s sorry guys could not get those two sites to open</font>thats why I posted the pics, you should be able to make some from those pics pretty easily.

ammcoman2
01-04-2006, 05:44 PM
Another method is to use Starrett # 54 hold downs. The only problem is that they are "out of sight" expense-wise if you buy them new.

There is however, a drawing of a similar item at http://www.metalworking.com/dropbox/Starrett_54_Hold_Down2.jpg

I made a set to 3/4 scale for my Ammco shaper using the shaper for most of the operations. I did the 5 degree angled ends on the mill but they could be done on the shaper. I just know you need an excuse to run your shaper!!!

I am going to make another set (full scale)for my recently acquired mill. They are not difficult to make but I would suggest flat ground stock or hot rolled steel as cold rolled will warp.

Regards,

Geoff

ammcoman2
01-04-2006, 05:53 PM
Just found out that the file will not access from the link I posted.

It is in http://www.metalworking.com/dropbox/_2004_retired_files/

Scroll down to the Starret 54 file.

regards,

Geoff