Bed clamps for Emco PCMill

[Coopertje]

To be able to machine the cylinder block for the V8 engine I am working on I could not use the vise because of height limitations in the machine. I have the bed clamp set on my to do list for a long time already, but never really needed them so they where more a nice to have then a must have.  Until this Christmas holiday, the only way to machine the block in this relatively small CNC mill is to clamp the block straight  on to the machine bed. Though to post the process of making them here, maybe it inspires others

Went to the scrap yard and found a nice piece of 25x25mm steel at 0.60 Euro a kilo. On the mill I squared it up and milled it to the required dimensions



I got the 2 stationary blocks from the material just before the hole that came with the scrap piece.



Marked the 30 degree angle on the remaining bar and used the band saw to rough cut the parts



The cut of parts where cleaned up on the mill. To get the 30 degree angle I used the blocks from my clamping set. Really quick when the required angle accuracy is more or less









The sliding part of the clamp received a spigot



And the stationary part of the clamp received a matching slot



Drilled and tapped 2 times M6 in the long T-nut



Milled a slot in the sliding part of the clamp



Then mounted the parts I got together and placed them in the vise. Used a feeler gauge and placed it at the outer edge below the T-nut. I did this to make the sliding part of the clamp slightly non-perpendicular. In this way the clamp will force the work piece towards the machine bed when tightened.



Cleaned up the surface with some emery paper



And put them in the blackening solution



Below a shot the clamps in use. I have added 2 clamps that I made to mount my vice to the milling table to give the complete set-up more stability. Do not know if this is really necessary but in my opinion it will not hurt. Do not want to think about the block getting loose during CNC milling….



I am glad I finally made these clamps, they are quite straight forward to make and work really well. One item to strike out on my to do list, now I just have 5 pages left.... .By the way, I have these clamps in Solid works, if there is interest I could make a quick drawing of the dimensions….
 

Regards Jeroen

[Roger B]

Nice job  and a useful addition to the mill 

[CHP]

Love it, smart Idea    now I have to make some

[90LX_Notch]

Jeroen-

I've seen these elsewhere and have had them on my to do list.  Now I am more inspired to make as set.  Thanks for posting this.

-Bob

[Graham G]

Hi there Jeroen, You have just reminded me of a set that I purchased several years ago, they were second hand that the time and a slightly different design, they are Austra tools version described as Austra tee slot vice clamp 9/16 part number 26312.
I have a problem using them as by the time I set them up on my mill, they are then at the maximum height and could only be used on maybe 5-6mm material it seems that the tee slots on my mill are to deep for the clamps (x2).
I guess the only way I can use them is to make a tee slotted plate with shallower slots to bolt onto the mill deck.
I think I will carry on with using my machine vice for now or use your design and make some that are more useable for my mill.
Any chance you could post a drawing of your clamps please.
Many thanks
Graham
 p.s. my mill is a Chinese Bridgeport copy

[Coopertje]

Thank you for your replies gents. Graham, the clamps you have are very nice for clamping thinner material. Or when you want to mill sheet metal screwed onto a piece of wood. In that case mine are a little high. In future I will make a set of these “low profile” clamps too. One size fits all does not exist here I am afraid. In my opinion you have the same amount of work making a clamp set as I did as when you make a sub-table with lower profile T-slots. On the other hand, did you try to clamp a bigger piece of material already? I would not be surprised that these smaller clamps grab the material very well. I tend to test my clamping by tapping the workpiece with a rubber hammer. Before doing anything I would try the behavior of your clamps…..
Please allow me a little time for the drawing, I put the clamps in Solid works as practice and did not create the drawings yet, I made the clamps as I went on behind the milling machine.

Regards Jeroen

[cfellows]

Nice thread, Jeroen.  I'm inspired to make something similar for my CNC mill.

Chuck

[sshire]

Very nice, Jereon
What are you using for blackening?

[Coopertje]

Thanks Chuck. Glad to be able to return the favor, you have inspired me already many times. Your Ardiuno dividing head is on my to do list, bought the hardware some time ago, just need the trigger and time to get started.

Stan, Google the following terms “frost-auto-metal-blacking-kit”. For small parts that can be heated I still use my torch and dip the heated part in a bucked with old motor oil, much quicker then to use the chemical way. For the larger parts (or the ones that cannot be heated) I use the chemical route. Below the steps for the chemical process:

1)   Degrease liquid -> about 10 minutes
2)   Wash the parts in normal water. I have found that it is important to dry the parts well before putting them in the blackening solution. If you don’t do this you will get stains on the part!
3)   Blackening fluid -> 3 – 5 minutes
4)   Wash the parts in normal water
5)   Sealer liquid -> 10 – 15 minutes
6)   Hang the parts away to air dry. I normally leave them hanging for about 24 hours and after I clean off the remaining sealer liquid with a towel.

You will not be disappointed with this set, in my opinion the parts look better when they are black and at the same time they are better protected against rust.

Regards Jeroen

[Coopertje]

Graham, i thought i had these things in CAD but I do not have them. I will measure what I have made and put that in solid works. I am currently abroad for work, need to aks more of your patence.

Regards Jeroen

[Lew Hartswick]

Using the "step blocks" from the clamp set for an angle.  Now why didn't I think of that. :-)  Like it!!!!
   ...lew...

[Coopertje]

Hi Lew, most of the times the solution is right in front of your eyes, just too many times we do not see it though....

Attached the drawing of the parts, hope they are clear and without missing dimensions. If there are errors etc please let me know so I can update them.

Regards Jeroen

[chucketn]

Thanks for posting the clamp plans. On my "to-do" list.

Chuck

[CHP]

Thanks for posting the  plans of the clamp
another project in my book
cheers
Luc

[Arbalest]

Thanks for posting the  plans of the clamp
another project in my book
cheers
Luc

+1 Many thanks!

[kuhncw]

Thank you for the drawing.

Chuck

[Meldonmech]

   Well done Jeroen, nicely presented and drawn.

                                                                               Cheers David

[Coopertje]

Thank you all for your reaction, now I know that I did not spend my time for nothing. Even though it was a nice practice, never made a drawing before in Solid works other then a quick sketch with some dimensions for my own use. Its not so easy to make a plan that looks organized and understandable for other people when putting all the parts in a single sheet, got more respect for the complicated and well organized plans from for example Julius that are in the download section.

Good luck with the build of the clamps, please post some pictures here (on the forum) when you have made them, I am sure that there will be variations, nice to see and learn!

Regards Jeroen

[CHP]

Jeroen
did you receive my email with pictures??

cheers

Luc

[Coopertje]

Hi Luc, I have received them. I feel ashamed that I did not replied to you, I believed I did.....live got in the a way a little lately. You have a very nice machine, did you already make some parts on it?

Regards Jeroen

[CHP]

HI Jeroen

Yes I did with the original system, one or two robots for the college.
I have all new drivers that I've build with TH 6064 and BUG heat sink
to keep them cool. I'm also monitoring the temp with temp sensor
on each chip. I took half the original stuff out about two month ago
and on my way of putting everything back together. I did convert that small
lathe to CNC and they are going to be driven with Mach3 on the same computor
and a rotary switch to change the output. The board and controller that I build are
5 axes ready for stepping up
Ill post pictures when all done

cheers
Luc

[Graham G]

Hi there Jeroen, Many thanks for the drawings, I will get onto them straight away while the idea is fresh.
graham

[Coopertje]

Hi Luc,

That sounds like a nice setup you are building. Should be no problem with Mach3 to have 2 machines on the same PC, you can program machine profiles and select at start-up. Never used it though, i like to be able to run both machines at the same time. 5 axis should be enough    I have my hands already full with 4 axis simultaniously....

Your welcome Graham, enjoy the build!

Regards Jeroen

[wla421]

Hi,

I am interested in making a set ( or 4 ) of these clamps, but I can't find the plans for them Could a forum member that has been here for a while lead me in the right direction.

Thanks.
George

[Vixen]

George,

Have a look at reply #11.  Jeroen posted them as a PDF file back in January

Oh, welcome to the forum

Mike

[wla421]

Mike,

Two thanks...

One for the welcome and one for showing me where the pdf was.....

Downloaded and printed it.

Got some weekend fun ahead.

George