[NN2]

The company I work for makes pistons for hydraulic cylinders. I need to find a way, if possible, to cut a large quantity of them in half. The largest measure 8.5" dia x 1.5" thick. The cost has to be around the $3 ea mark. There is a demand for up to 1500/month so the process has to be somewhat fast. Does anyone know of a company or way to do this? I am located in Troy, MI. I've searched the internet but couldn't find much and have always found the members of forums to be of real help and knowledgeable. Thanks

,Nick

[Geof]

Slicing an 8.5" diameter by 1.5" thick disc into two discs 0.75" thick?

You will need a bandsaw with a capacity of at least 8.5"; I would get one with a capacity of around 12" diameter.

Then get a piece of pipe or tube with and ID a bit larger than 8.5" and long enough to hold securely in the vise on the bandsaw.

Drill and tap three holes 3/8"-16 centered about 0.8 from the end of the tube and screw in some caps screws so the thread sticks inside the tube to a diameter less than 8.5".

Drill and tap another three holes 3/8"16 centered about 3/8" from the end of the tube and put setscrews in these holes.

Put your disc in the tube up against the capscrews that go right through and tighten the three setscrews to hold it in place.

Put the tube in the saw lined up for cutting the disc.

Cut the first disc then without moving the tube put in the next and repeat for however many you need to cut.

For smaller diameters use longer cap screws and setscrews or make a fixture using a smaller tube.

[BillTodd]

1500/month, you're going to need several bandsaws.

What about waterjet?

[NN2]

I missed adding a couple specifications. The half will be like a half moon. Also, the kerf can not exceed .100". I know a band saw would work but thought it would take a very long time.

[Geof]

I missed adding a couple specifications. The half will be like a half moon. Also, the kerf can not exceed .100". I know a band saw would work but thought it would take a very long time.

Cutting across the diameter?

8.5" wide, 1.5" deep with a good bandsaw should take not more than five minutes; that is not a very big cut. The kerf will be less than 0.10" and the precision could be +/-0.01" with a bit of care.

Holding them is simple: Get a piece of flat material about 12" inches wide, long enough to grip in the vise and extend about 6" past the blade.

Put a ring of four tapped holes on a 10.5" bolt circle and make some slotted stops to bolt onto these holes; these holes can be 1/4"-20

Tap two other holes across the bolt circle in line with the vise and get some clamps such as used on a milling machine table; these holes should be 3/8"-16.

Adjust the slotted stops for whatever size is being cut and clamp the disc down with the clamps.

Adjust the downfeed stop on the bandsaw so the blades stops just as it touches the flat material; you don't want to slice the end off your fixture.

[NN2]

Water jet was quoted at $8 ea. Yes, band saw would do it but would take another operator at full time to do 1500/month. I wanted to check and make sure I wasn't making this harder than it is. Ideally, I'd want to throw it in a V-block type clamping fixture under a fast cutting carbide circular saw blade. If I could figure out something fast and not too much $$ I'd do it myself for the $4500/month. Thanks guys

[Zumba]

Easy enough to do it on a bandsaw. I would clamp a fixture with dowel pins and toe clamps. Stack at least 3 at a time on a 10x18 saw.

$8/ea is high. $3/ea is kinda low...

[NN2]

We found a place to do it not to far away for $1.10 each. We'll just have to wait and see what kind of quality it is. Thanks for the help.

[gridley51]

If I had to do this,I would saw them in my Amada HA250 bandsaw.Stood on their edge,sawing down 8" through 1.1/2" thick.
Easily manage 20 an hour,which on a saw would be $2.25 ea.

[fpworks]

If I had to do this,I would saw them in my Amada HA250 bandsaw.Stood on their edge,sawing down 8" through 1.1/2" thick.
Easily manage 20 an hour,which on a saw would be $2.25 ea.

I have the same saw...this job would be cake. 20/hour is no problem at all.

[JWB_Machining]

I did an operation similar to this on my band saw where I was cutting steel 2" Diam down it's length of 6.25" What I did, which may not get you within the tolerances you need was essentially create a U shaped jig out of wood. Obviously it can be done out of metal to be more accurate. I locked in txo bolts in my T slots so that I could push a piece of wood up against them and it was perpendicular to the saw blade. I held this down with table clamps so it wouldn't jump and to take a little stress of the backstop bolts. I Then centered up my piece of steel using the slot in the table, this may require some adjustment depending on how centered your blade is in the slot. I then pressed a piece of wood on both sides of the stock and clamped them to my backstop piece, thus making the U. The Piece didn't jump and it led to a nice cut. The key was making sure my back stop was perpendicular and that my stock had a nice flat surface to press up on. Like i said if you did this with Metal it'd probably be even better.

So if that other place doens't work out you can try that.