Hoss's G0704

**hoss2006** · 02-21-2011, 05:53 PM

Originally Posted by pete from TN

Nice work on that cylinder, You have inspired me to build one finally too. I started on it last night. I am making it a little different tho than you have done. As you mentioned I do not need more than about 1/4 inch of travel tho so mine is gonna be more like the Tormach one I suppose. What pressure are you planning on running this on? What type of O-rings did you go with on the pistons, I am still working on that part of it did you use poly O-rings for frictional resistance? The three piston setup you have build is very creative and should work great. Are you venting the area under the piston to the atmosphere? It looks from the pictures that your retract port is only on one of the pistons, did you choose to use the middle one for any particular reason? I am curious to see how you implement this cylinder on the machine. Is sure gonna be nice to get some REAL clamping force on it now I think. I know you sound like you do not intend to use the TTS system but I am using it and I want to get some serious force on it. What size bellevilles are you gonna be using for it? I bought some from Mcmaster carr and they are certainly strong enough but they are rather large in diameter. I was hoping to get some like Tormach used that appear to be like 1-1.25 in diameter but I am having some difficulty finding a set that will generate the necessary force that are not like 2" wide.... Nice work here man and I think that expecially for us TTS guys, it is a welcome sight to see someone homebrewing a high tension cylinder for the mill. I am assuming this is for your 0704? Peace

Pete

I'll be running at 100 psi there or abouts.
I'm using Buna-N O-rings, medium-soft.
The top 2 stages are for retracting, the bottom one vents to atmosphere.
I got these bellevilles from McMaster # 9712K446, 1.250 OD, .531 ID .090 thick, 1390 lb load.
McMaster-Carr
Chances are Tormach is stacking theirs like this (())(()) etc. to get to 2000lbs plus with a smaller spring.
Hoss

**eartaker** · 02-21-2011, 06:04 PM

Hoss,

That is awesome. Do you plan on changing out the system that you have on the X2 to something like this as well? I built a 2" single piston double action but that doesn't compare to this monster. Also how to you plan on taking the spring release load off of the spindle bearings?

**pete from TN** · 02-21-2011, 06:20 PM

I see that you have cross drilled into the body of the cylinder above the piston and then down on top of the piston face. The same applies to the reverse. Do you think that if you just drilled into the side really close to the top of the cylinder it would work too? I am making mine as I said a little different than yours as mine will not have the intermediate parts between the cylinders, instead I am putting an o-ring on the face between the plates. That way I can cut down on the overall height. I can also drill in and cross drill the ports if necessary but not sure if I will yet. So you feel that a medium buna type ring will last a good while in the friction dept? What are you using for a clearance? I have a blown bimba cylinder here that I was gonna cut up when I made the piston rings that I was gonna measure their clearance specs on but if you are already there...? I really like what you are doing here and I applaud your resourcefullness. Mine is gonna be a 3.75" bore with a 3/4 internal race as I am looking for more in the range of 3000pounds force. That Belleville looks pretty stout and is similar to the ones I am looking at. SO to get 2600 lbs as you said you are stacking like...(( )) (( )) for however many stacks necessary for your intended travel... Did you say it was gonna be around 1/2 inch? What machine is this for? Thanks for the information, I will try to post some progress pics of mine in my thread "Finally Getting started" I am machining mine completely with the mill, Using my boring head to make the smooth bores for the cylinders. The pistons obviously will be lathe turned as will the spacer journals... Did you make the piston shaft from solid or is that a large bolt that has been reclaimed? Nice work as usual Hoss, you certainly inspire me!! peace

Pete

**hoss2006** · 02-21-2011, 06:21 PM

Originally Posted by eartaker

Hoss,

That is awesome. Do you plan on changing out the system that you have on the X2 to something like this as well? I built a 2" single piston double action but that doesn't compare to this monster. Also how to you plan on taking the spring release load off of the spindle bearings?

The X2 has all it needs with it's present setup. It doesn't need more pull.
This will work like many others that have been done like tormachs and scissor
the drawbar.
Hoss

**Maglin** · 02-21-2011, 06:24 PM

Looks like to get .25" of travel you would have to stack 11 of these which gives you a dimension of 1.254" of required space. How much space is available to put these in? I would think 1390# of force is enough for the drawbar. And if you happen to load them up just a little you could reach 1500# pretty easy with still a decent amount of travel. How much travel is needed btw to fully engage the collets usually? I have 1218# of force at 60 PSI so I would have to run 100 PSI just to be able to compress these at their 2,003# of force when flattened.

**hoss2006** · 02-21-2011, 06:45 PM

Originally Posted by pete from TN

I see that you have cross drilled into the body of the cylinder above the piston and then down on top of the piston face. The same applies to the reverse. Do you think that if you just drilled into the side really close to the top of the cylinder it would work too? I am making mine as I said a little different than yours as mine will not have the intermediate parts between the cylinders, instead I am putting an o-ring on the face between the plates. That way I can cut down on the overall height. I can also drill in and cross drill the ports if necessary but not sure if I will yet. So you feel that a medium buna type ring will last a good while in the friction dept? What are you using for a clearance? I have a blown bimba cylinder here that I was gonna cut up when I made the piston rings that I was gonna measure their clearance specs on but if you are already there...? I really like what you are doing here and I applaud your resourcefullness. Mine is gonna be a 3.75" bore with a 3/4 internal race as I am looking for more in the range of 3000pounds force. That Belleville looks pretty stout and is similar to the ones I am looking at. SO to get 2600 lbs as you said you are stacking like...(( )) (( )) for however many stacks necessary for your intended travel... Did you say it was gonna be around 1/2 inch? What machine is this for? Thanks for the information, I will try to post some progress pics of mine in my thread "Finally Getting started" I am machining mine completely with the mill, Using my boring head to make the smooth bores for the cylinders. The pistons obviously will be lathe turned as will the spacer journals... Did you make the piston shaft from solid or is that a large bolt that has been reclaimed? Nice work as usual Hoss, you certainly inspire me!! peace

Pete

I don't have enough room to just drill the air passage through the side, the piston comes all the way to the top and there is a seal between the stages.
I'm not going to pretend to be an air cylinder manufacturer so I don't know what seals work best, these looked good to me, time will tell how they hold up.
McMaster says they are oil resistant and about the hardness of a car tire.
I'm using these bellevilles for the TTS version right now so they only need to compress about .050 to release.
The cylinder needs to move about 1/4 inch to make up the clearance at the top and bottom so parts aren't rubbing themselves to death.
Hoss

**hoss2006** · 02-21-2011, 06:56 PM

Originally Posted by Maglin

Looks like to get .25" of travel you would have to stack 11 of these which gives you a dimension of 1.254" of required space. How much space is available to put these in? I would think 1390# of force is enough for the drawbar. And if you happen to load them up just a little you could reach 1500# pretty easy with still a decent amount of travel. How much travel is needed btw to fully engage the collets usually? I have 1218# of force at 60 PSI so I would have to run 100 PSI just to be able to compress these at their 2,003# of force when flattened.

You need to stack 10 of them to get about .050 worth of travel to release the tools, .050 should be plenty for TTS.
You only have .005 movement per spring left from load deflection to flat.
You can stack as many as you want if you make a longer drawbar.
I won't be using these springs down the road when I actually need 1/4" of spring travel
cause I would need a stack of 50.
I'll find something more suited.
Hoss

**pete from TN** · 02-21-2011, 07:15 PM

I am on board with what you have done here. It should work great. I guess when you say you do not have enough room that you mean the seal part that is kinda locking the two parts together is protruding down into the chamber underneath a bit which makes it impossible to get the piston to the top... My design does not use those intermediate pieces so I was kinda hoping that since I intend to use a 1/4 thick piston plate and my o-rings are probably gonna be 1/8 inch that leaves that little bit at the top that would be below the port probably for air to enter the chamber. Honestly I think your method is probably better for me in that I would just drill thru and then down into the chamber in the bottom or base of the upper cylinder plate.

I had read on here that most said the travel necessary to enact a TTS tool release was more on the lines of .100" . You are saying it is around .050" and then some room for movement so the parts do not rub on the clamping mechanism. That sound great to me. I should have around .313 of travel when it is assembled. It also looks like you are gonna mount this thing with some studs on the bottom plate. IS that bottom plate just for mounting really or does it serve another purpose... I like the way Tormach did their system with that apparently steel 1/2 plate for going underneath the tophat. They are pretty clever on a lot of things lately. You can see their triple stack cylinder is basically what you are making but using square profiles and probably a sourced triple stack adapted to fit. I tried to find a suitable setup like that but could not for a reasonable amount of money. I also noticed that their original prototype setup was a double stack system with around six bellville stacks and their new one for sale is a triple stack with what appears to be an eight stack setup. They said the reason for the change was to allow a lower pressure setup but I am wondering if they left out the idea that they are now using MORE pressure and a stronger cylinder. They also said it was a four inch piston in the video I think. The way I got it figured with a 3.75" bore triple stacked like that 3k should be easy at around 110 or 120 psi. My vertical compressor runs up to 140PSI and has air to spare. The setup should really be pretty miserly for consumption. Another little tidbit there is that they apparently use flow regulators on their solenoid. I think that is a really good idea altho the video still shows a rather harsh and quick actuation. I am gonna drill my ports with a really small hole that I will plug with a 4/40 setscrew to slow the actuation. If I can get it to be like a soft psshht of maybe a second or two I will be happy. I do not think slamming that kind of pressure is good for anything really. The interesting thing here to me is that while your leveraged purchased cylinder for the freak worked great the complexity of it compared to this is actually more in terms of necessary parts and wear and tear items. This is simpler and will produce obviously a higher holding force available with just a simple to build cylinder setup. Anxious to see what you do with newfound power man. I suppose if you are temporarily using the TTS you have built for that forces but really if you go with some other tooling that does not require the forces all you would need to do is regulate the incoming pressure down to get the force you need. Simple, quick, efficient... Well done my machinist friend!! You are never standing still and I like that. peace

Pete

**Maglin** · 02-21-2011, 07:31 PM

I was figuring with .090 thickness and .114 overall height that gives you when flattened a movement of .024"/washer @ 2003#. That is how I came to my conclusions. I've never played with these so maybe I'm looking at it wrong. I didn't know so little movement was needed to release and lock the tooling.

What kind of compressor are you planning on using? A small pancake style? Something quiet or something cheap? They usually don't come together in a single package (cheap and quiet).

You cylinder looks excellent btw. I love your design. It would definitely look nice anodized.

**pete from TN** · 02-21-2011, 09:03 PM

You are right about the sizing of the bellevilles but basically the way I think you need to figure is that you preload for the load rating and then figure the remainder is the release travel or somewhere in that range. You have .024" of total travel to flat( you never want to go totally flat) and the rating is 1300 or whatever at .019" so you can figure that you have .005" per washer to work with. Depending on how you stack them you can either stack them nested like this (( or large diameter to large diameter like this (). The former increases the total weight by double the rating and the latter leaves the weight rating the same but doubles the available travel. So if like hoss said you stacked that washer like this (()) you are doubling the rated weight and increasing the available travel two times. That is how you work them to arrive at increased weight and travel for your particular application. For my uses I am wanting to operate in the 3k+ range but I am having trouble finding a set of washers that can give me that weight and allow what I was thinking needed to be like .100 of travel from static load and not be a belleville stack four inches tall!! This washer has promise as I said and looks to be similar to the one I was looking at which is the 9712k436. It has similar features and travel. I am actually glad to hear that .050 travel will possibly work so I think now I can just order what I need and figure for a bit less available travel. Another thing to consider is that the weight ratings and travel stat at the load rating is not a linear number. If you see a graph of a typical belleville, the plot looks like an arc that increases as deflection increases so you can also figure that if you choose a washer that has MORE weight than you need you can figure your amount of deflection at a lesser number which does two things, it decreses the load at rest so to speak and increases the available travel a bit. I have been pulling my hair out on this one and already ordered a set that while it would work they are too large in diameter for what I want it to be. I am also curious as to whether or not Hoss knows how much the ID shrinks or even if it does when the washer depresses. I was looking at washers that have a smaller ID for my 7/16 drawbar shaft. I am unclear if Hoss is planning on making a new drawbar. If he is he can make it a snugger fit in the bore of the spindle to allow for a more concentric setup which will help when you are cranking the speed up like we are with these belt drives. This is all very interesting stuff and there is much to learn here. Just this thread alone is an interesting read and there is a lot of cool ideas and concepts that are really not any accident. Hoss says he does not want to sound like a pneumatic cylinder manufacturer but he has certainly designed a three stack cylinder that anyone would be proud of. I cannot wait to see it clamp down on a belleville stack with some serious pressure. Gonna be really cool.... peace

Pete

**hoss2006** · 02-22-2011, 05:05 AM

This video shows the air cylinder does work plus a little turning with the mill.
The power drawbar should be working later today as long as the UPS guy didn't get stuck in ice.
Hoss

[nomedia="http://www.youtube.com/watch?v=i6eas5uhvnA"]YouTube - G0704 Simple Turning Tool Steel.wmv[/nomedia]

**paulsv** · 02-22-2011, 11:41 AM

Hoss- I noticed on your G0704 Projects page, in discussing motor options, you listed a VFD / 3 phase motor option, and mentioned that the motor was quite large (56C frame, with mounting bolts on a 5+" bolt circle) and that you were looking for a smaller motor option. There is a 3/4 hp 3 phase motor on surplus center right now that appears to be quite a bit smaller- it says it has an 85mm bolt circle on the mount, and the shippinng weight is only 16 pounds. Looks like it would fit on the belt drive mount. Price is right too. I assume you would use the same VFD (next size down is 0.5HP). It's a 3400 RPM Motor, but with the high speed pulleys on the belt drive, you would still get respectable speed. Also, the 3400 rpm is at 60 HZ, and the vfd's generally have the capability to go up to 100 HZ. Perhaps you could get more rpm by overspeeding the motor a bit?

Surplus Center - 3/4 HP 3400 RPM 230/460 VAC 3 PH MOTOR

**kd4gij** · 02-22-2011, 12:23 PM

Hi Been folwing this forum on the G0704 scence it started. Just orderd A G0704 bassed on all the good revues here. It is going to be manuel for awhile.
Would it be posible to build a power feed for the x axes that could me incorperated in the cnc build later on. Thanks

**pete from TN** · 02-22-2011, 12:41 PM

As usual, looking forward to seeing it work with the high pressure and tooling releasing. Incidentally I ordered some of those same bellevilles you used from McMaster last night along with all the O-rings and fasteners I need to complete my triple stack. You know you're cool when you are building a TRIPLE STACK ANYTHING right... haha. I also picked up my new Tormach Tension and Compression Tapping head with a set of specific sized collets for the taps I most use as well as some other odds and ends. God I love tax return time!! This is really interesting to me this whole pneumatic cylinder setup and it is what I have been wanting to put atop my millhead for some time to take full advantage of the TTS system and quick change tooling. Who knows, once I get the damn thing working right maybe I will take a crack at the toolchanger at some point. My problem is currently I am trying to make some cash with this machine and that takes away from play time with it. Luckily the stuff I am making is kinda play time/work time so it is all good. I gotta thank you again for all your inspiration and ideas that has been a contributing factor to my own CNC illness. This stuff is just too cool for words and once you go CNC you can NEVER go back I think... peace

Pete

**hoss2006** · 02-22-2011, 01:55 PM

Originally Posted by paulsv

Hoss- I noticed on your G0704 Projects page, in discussing motor options, you listed a VFD / 3 phase motor option, and mentioned that the motor was quite large (56C frame, with mounting bolts on a 5+" bolt circle) and that you were looking for a smaller motor option. There is a 3/4 hp 3 phase motor on surplus center right now that appears to be quite a bit smaller- it says it has an 85mm bolt circle on the mount, and the shippinng weight is only 16 pounds. Looks like it would fit on the belt drive mount. Price is right too. I assume you would use the same VFD (next size down is 0.5HP). It's a 3400 RPM Motor, but with the high speed pulleys on the belt drive, you would still get respectable speed. Also, the 3400 rpm is at 60 HZ, and the vfd's generally have the capability to go up to 100 HZ. Perhaps you could get more rpm by overspeeding the motor a bit?

Surplus Center - 3/4 HP 3400 RPM 230/460 VAC 3 PH MOTOR

Good find, It's not much of an upgrade but at least it would get someone running.
I'll add it to the list.
Thanks, Hoss

**hoss2006** · 02-22-2011, 02:11 PM

Originally Posted by kd4gij

Hi Been folwing this forum on the G0704 scence it started. Just orderd A G0704 bassed on all the good revues here. It is going to be manuel for awhile.
Would it be posible to build a power feed for the x axes that could me incorperated in the cnc build later on. Thanks

Good choice, you'll be able do lots of stuff with it.
Not as big as some mills but very capable for it's size.
Some have a bias against them thinking they aren't REAL enough, whatever that means.

That's from ignorance more than anything.
A powerfeed would be pointless once CNCed, you can jog the axis just like a powerfeed.
You could cnc just one axis for now and use it like a powerfeed for what you would
spend on a powerfeed and then you're already 1/3 the way there.
Hoss

**hoss2006** · 02-22-2011, 03:52 PM

Guess I'll finish the power drawbar tomorrow, seems ups is afraid of a little snow.
The mailman made it out.
what ya gonna do.
Hoss

**dsdmax** · 02-22-2011, 03:58 PM

hopefully the air cylinder is going to be a subject of another DVD ... i just ordered the first two. Looking forward to building an air cylinder - that would be a project i wouldnt know where to even start on my own.

thanks again for all your posts - following along your builds has taught me a lot and made this hobby infinitely more enjoyable!!!

**hoss2006** · 02-22-2011, 04:03 PM

The air cylinder would probably be part of an ATC DVD since it all works together but that's
far off.

I'll have to make another because I didn't do much documenting the build of this one.
Probably more oomph too.
Hoss

**hoss2006** · 02-23-2011, 02:42 AM

Another project can be added to the done box, finished my spindle square tonight since ups never showed.
Tried out my powder coating kit too, came out ok, next time I'll clean the old toaster over better,
got a few crumbs in there but oh well.

Tramming was a piece of cake even the first time.
Another cool tool added to the toolbox.
Hoss

[nomedia="http://www.youtube.com/watch?v=vf6BnLRcpi8"]YouTube - G0704 Spindle Square.wmv[/nomedia]