[SScnc]

I do have an air compressor but like most, it's incredibly LOUD. Although I am building a silent compressor I've been wanting to try this electric draw bar idea out.

I spent about a full day getting this all put together and operational and I'm impressed with how well it works. This little linear actuator is very powerful, it's rated at 900 lbs. "push". I first had 3/8" rods for the cross bars and the motor quickly bent them. So since it looked like the idea was actually going to work, I changed the cross bar rods to 5/8" and they work fine.

While I was at it I also installed the top bearing cooler, the coolers will be much more useful when I get the spindle speeds closer to 8000 RPM but they help now.

I really think that this electric (or any power drawbar) would work much better with R8 instead of the MT3. I had to use 10 Belleville washers to get enough travel so my TTS style holders would release. I may change to an R8 spindle later.

Now instead of using the spindle lock, wrench and brass hammer, I just press a DPDT (on) OFF (on) toggle up or down.

I personally haven't seen this done and thought you guys may like to check it out.

Best,

Steve

EDIT: Oh yeah, I forgot, the 1/8" lever bars are just temporary, I'm going to change them to 1/4" thick due to the strain placed on them during operation.

[hoss2006]

Pretty cool!
Where did you get the actuator?
Any video?
Hoss

[SCzEngrgGroup]

Very nice! I've considered taking a similar approach, using DC motor or stepper and several stages of belt or gear reduction.

Where did you find the actuator, what did it cost, and what are its specs?

Regards,
Ray L.

[SScnc]

Thanks guys, I meant to put a link for the actuator in but forgot to. I got it from our favorite supplier, SurplusCenter HERE and all the specs are there. At only 22 bucks I figured it was worth a try.

I bent up a sheet metal cover for it. No video of it Hoss, I thought about it and may do so and put it on Youtube.

[SCzEngrgGroup]

Thanks guys, I meant to put a link for the actuator in but forgot to. I got it from our favorite supplier, SurplusCenter HERE and all the specs are there. At only 22 bucks I figured it was worth a try.

I bent up a sheet metal cover for it. No video of it Hoss, I thought about it and may do so and put it on Youtube.

Yikes! Does it really take 24 seconds to go full travel?

Regards,
Ray L.

[SScnc]

I don't know, I didn't run it full travel yet but to release it takes 8.5 to 9 seconds. Same for return. Not as fast as air but a whole lot faster than the hammer method.

It seems reasonably quick to me. Something else I forgot to mention, I did a test with the mill motor removed and with this actuator located directly above the drawbar and it easily compressed the drawbar fully without any levers. I would prefer to mount it this way but my water jacket on the mill motor prevented that so that's why I used the levers. So I think regular X2's would be able to do it this direct push way, I just don't want to give up my water cooled motor since it's already done.

Steve

[Nateg281]

I do have an air compressor but like most, it's incredibly LOUD. Although I am building a silent compressor I've been wanting to try this electric draw bar idea out.

I spent about a full day getting this all put together and operational and I'm impressed with how well it works. This little linear actuator is very powerful, it's rated at 900 lbs. "push". I first had 3/8" rods for the cross bars and the motor quickly bent them. So since it looked like the idea was actually going to work, I changed the cross bar rods to 5/8" and they work fine.

While I was at it I also installed the top bearing cooler, the coolers will be much more useful when I get the spindle speeds closer to 8000 RPM but they help now.

I really think that this electric (or any power drawbar) would work much better with R8 instead of the MT3. I had to use 10 Belleville washers to get enough travel so my TTS style holders would release. I may change to an R8 spindle later.

Now instead of using the spindle lock, wrench and brass hammer, I just press a DPDT (on) OFF (on) toggle up or down.

I personally haven't seen this done and thought you guys may like to check it out.

Best,

Steve

EDIT: Oh yeah, I forgot, the 1/8" lever bars are just temporary, I'm going to change them to 1/4" thick due to the strain placed on them during operation.

That looks awesome! I'd love to set something like that up for my X2....

[digits]

Very cool - and presumably very quiet!

I'm glad someone's proved this is quite doable

[Crevice Reamer]

Well done Steve! Good pioneering effort!

CR.

[pete from TN]

Very nice man, very nice..... I have been looking for something like this to do the power drawbar on my Lathemaster cnc mill. What is your drawbar force and what is the actual throw of the unit from relaxed to when the tool actually releases? I have just ordered one of these units to see if I can make it work on my machine. I am thinking about a four to one ratio on a lever and I can get the 3000psi pressure I am after. I suppose it is pretty quiet no? Mine will probably look vastly different from yours when I get it done but it will obviously work the same way. From looking at the Surplus center website they also have a 1 5/8" throw unit and I almost went with that until I saw that it is nearly eight inches long, three inches longer than the one you used. The power drawbar is something I have wanted to do for awhile now and this may just do it for me. The only real issue I have with this is I will eventually want to automate the whole thing for a toolchanger setup of some sort so it will I suppose need some sort of limits to allow it to stop and start and only go as far as necessary to facilitate a toolchange. The dpdt switch will work fine for now tho. My cnc4pc c11G breakout board has relays for controlling ac units but I have no idea how this would be accomplished with this or wether or not a reversing setup could be done. Any ideas on this from anyone here would be most appreciated... Sorry for all the questions but I am not an electronics expert whatsoever...

Anyways, very nice unit and great looking little X2 ya got there. I really like your ingenious ideas and keep up the good work man....peace

[SScnc]

Thanks guys,

I'm quite impressed with it, it's working better than I thought it would.

And per Hoss's request, I just did a YouTube video of it in operation (my first YouTube upload) the quality isn't too good I guess because I used the memory card.


[ame="http://www.youtube.com/watch?v=Blf7lB9bQ8Y"]YouTube - X2 Electric Draw Bar[/ame]

[pete from TN]

I like it man, nice and quiet... It does seem like there is a tad bit of unnecessary travel in the beginning of the stroke but it does not take that long really. Of course a pneumatic setup is real quick but just not having to hear an impact wrench, compressor run, or reach for any tools is worth the price of admission, speaking of price, nice that surplus center is so inexpensive with it. I love that place, bought several items for machines and stuff over the years...

If you do not mind, what is your total bellville pressure? I am trying to figure mine out currently and the actuator is on order now so gotta order some bellvilles... did you have to remake the drawbar? I think mine is not gonna be long enough to accept the stack of washers, my scissors large washer and still reach the collet. What say ye? peace

[pete from TN]

All I do is go to the youtube site and play the video, then copy and paste the url from my browser in my posting... works fine here... thanks man...peace

[SScnc]

Thanks Pete, I thought I had tried that but I guess not. There is a bit of unneeded travel at the start, I sometimes hold the retract switch a little longer but I like to make sure the spindle is clear.

Yeah, SurplusCenter is great, I can't believe how inexpensive these are yet so powerful. I've bought from them several times and their service and pricing is always good. I always check their site out first when I'm planning any project.

I'm not sure of the actual Belleville pressure, I don't remember what their rating is right now but they're the ones Hoss specified from McMaster-Carr. BTW: Hoss's pneumatic one was the inspiration of this (of course). I'm now using 8 Bellevilles and they really hold the TTS style holders. I did have 10 Bellevilles on it but found that 8 gives me good clearance.

Pneumatic is much faster of course but until I have my silent compressor finished I'll be using this setup, maybe even after.

The actuator does come with a reed type sensor on it to count revolutions so that "could" be incorporated into an automatic system, or limit switches would be simple enough.

I did change to 1/4" thick levers I CNC'd for it and moved the pivots closer together to make the cycle faster.



Even though I don't have an RF45, I've been following your build, very nice work you've done, first rate and very interesting. I'll be curious to see what you end up doing for a power drawbar on it. I hope I answered all your questions, ask if you have more and I'll be glad to help.

Steve

Regarding the actual drawbar, I didn't have to change anything but I did add a brass sleeve about 3" long I turned on the 9x20 to the bolt that keeps the belleville stack neat and centered and that definitely helped make it very smooth.

[whitehedr]

I have one of the devices en route as we speak. Do you have any drawings that you are willing to share?

RWW

[whitehedr]

I have one of the devices en route as we speak. Do you have any drawings that you are willing to share?

RWW

[SScnc]

I have one of the devices en route as we speak. Do you have any drawings that you are willing to share?

RWW

It's unusual for me not to design every detail in CAD these days but I didn't do any drawings for this project except the levers after the fact. Since I didn't know how well it was going to work I didn't want to spend allot of time on it. I just took a few measurements and did a couple of cardboard templates to check fitting and then transferred that to aluminum plate.

I feel several details could be better (isn't that always the case though) and probably will do some CAD drawings on new side plates. For example, the 5/8" dia. rod locations need to be relocated slightly, the top one to have the actuator more vertical and the lower one a little higher to allow for 10 Belleville washers with no clearance problem.

Another important thing that needs to be changed is some short slots need to be milled horizontally in the side plates right at the spindle pulley to allow room for the belt to be placed on the lower, low speed pulley for the occasions when you need lower speed for steel.

As soon as I do some drawings I'll of course post them. Keep in mind though that as I said, mine is different because I needed some clearance between the mill motor water jacket and the actuator. I picture on a standard X2 the actuator can be mounted directly above the drawbar with no levers needed and with vertical slots milled in the side plates for a rod to go through one side plate slot, through the hole in the actuator push rod and then through the slot in the other side plate. This rod will be needed to keep the actuator rod from rotating during operation. I think this arrangement would be simple and the cycle time can be as fast as possible, maybe 3 seconds (?).

Although I refer to a DPDT switch, all that is requred is a SPDT switch as long as they are momentary on (on) OFF (on) either will work and since the actuator is already fully wired up, hookup couldn't be easier.

Steve

[pete from TN]

Hey man thanks for the information. I am quite sure that mine will need to be vastly different from yours so I will just wait till it gets here and try it out. I was really looking for your drawbar force particularly and the amount of travel you allowed for to let the tts holder fall out. I am gonna have to order up some bellvilles and see what I come up with for mine. The idea is a great one I think and you are clever for coming up with it. I am glad you like my buildup I have done a lot of work on it and it is all starting to payoff. The power drawbar will be the cherry on top if ya know what I mean... thanks and peace...

Pete

[SScnc]

Hey Pete, yeah I do know what you mean.

I'll place an indicator on the collet and and see what the travel is but I haven't thought of a good way to measure or calculate the actual pulling force of the Bellevilles at the current adjustment.

I'll get back with the travel info.

[pete from TN]

Thanks man sure do appreciate it... Hoss has a link to a very good website that shows how to calculate the drawbar force based on the bellville washers and how they are stacked. A lot of it does not seem to be possible to me but apparently it is correct because I have seen similar information posted here... Peace man