Why not make a platform off the nose to set the butt of the lift cylinder on, then have a hoop over the top of the cyl connected to the frame of the plow. Apply air, cylinder expands, pushes the hoop up, pulling the plow with it. If you mount the cylinders with the rod ends down, you won't have to worry about sealing and venting the rod end, just leave it open.

 

Made the a-frame today, which does the heavy lifting. It takes the forward pushing horizontal force from the pair of air cylinders (not made yet), and converts it to a vertical force that in turn lifts the plow:
http://frederic.midimonkey.com/yard/.../IM002227a.JPG

Once I verified nothing hits, I removed everything and primed them. Hopefully if the weather holds out I'll paint it this evening, probably red to match the mower.
http://frederic.midimonkey.com/yard/.../IM002228a.JPG

I'm almost done making the steady rest (see other thread) so I may get a chance to turn the air cylinder bodies tomorrow. Or the end caps. Not sure what I want to make first. Probably the cylinders because the material is sitting on the floor next to my lathe.


Fordsix - There was no obvious reason why I didn't do as you suggested, other than I'm almost done at this point I do get a mechanical advantage from the a-frame assembly in the above pictures. To lift the plow by hand, requires about 80lbs of lifting force at the point where the mechanism attaches. Pulling the a-frame forward instead, requires noticably less than that (I didn't have a strain gauge to measure it). To lift the plow four inches, requires 6.5" of travel of the bottom of the a-frame, which is where the pistons will attach. Maximum lift of the plow is 6", so that means to lift to that height the air cylinders I make need to have 9.75" of travel.

Originally I was thinking one air cylinder to lift, but it was going to be a large diameter thing because of the force I need, and I was worried about cfm requirements. The air suspension compressor I have creates tremendous pressure (almost 200psi) but not any real kind of volume. So I thought maybe a pair of smaller air cylinders would be better than one huge one, based on pressure versus flow that I actually have to work with.

Ideally, I want to use a regulator and limit the pressure to the air cylinders to about 90-100psi. The mechanical leverage allows me to do this with smaller cylinders.

 

Find a spring type hanging scale, like a fisherman would use. They are good for approximating forces. I have one I bought at a hardware store for a project.

FYI- Crude calibration weights can be made with containers full of BBs (etc) at the post office by dropping in BBs until the postal weight flips to the next value. The postal scales always round up.

 

http://frederic.midimonkey.com/yard/...w/IM002230.JPG

All I need is to make the air cylinders, mounting, and install the joystick valve block and I'm good to go.

Actually, I need to find the joystick valve block. I *thought* I had placed it in my tool chest but apparently... I didn't do that. Maybe I remember *wanting* to put it in my tool chest.

Must be time to get the shovel out and dig through the huge pile of junk on the floor. I hope it's in my garage bay... because if it's in the other bay, I'm SOL. I lost a porsche G50-52 transaxle on that side which I still haven't found !?!?!?

 

Those fleeting "thoughts" that go with advancing senility....

 

Oh my, I've allowed this thread to fall so far behind what's going on.

Milled "ends" for the air cylinders that will slip over the a-frame arms to push and pull the plow up and down:
http://frederic.midimonkey.com/yard/...w/IM002275.JPG

Attached above part to air cylinders on both sides, then to the a-arms:
http://frederic.midimonkey.com/yard/...w/IM002276.JPG

And on the back as well, though this required some scrap material to be welded to the already modified bracketry underneath.
http://frederic.midimonkey.com/yard/...w/IM002280.JPG

Couldn't find the 4-way valve in the garae (suprise suprise) so I bought another one off ebay for $16 with shipping:
http://frederic.midimonkey.com/yard/...arkervalve.jpg

ONce the valve arrives, I'll find a place to mount it, and install the air fittings and hoses and it's done. Done I say... done!

 

"Done I say... done!"

Right... Until you find some new gizmo or attachment/modification for it!!!

I see you found some air cylinders rather than making them. It takes a lot of time and effort to make cylinders that work well.

 

Yes to both.

I made four useless air cylinders. Lathing, sanding, honing, made no difference. They either shredded o-rings or leaked real bad - even when oiled or greased.

So for $30, got a pair of identical air cylinders a bit shorter than I wanted but good enough to get the job done.

When I was looking a few weeks ago I didn't find anything suitable... that wasn't ridiculously priced. Just a matter of luck I guess.

But the plow does go up and down

 

Excellent!

 

hey eric, should i give fred the news now, or make him wait till it snows and then just show up at the house???

 

What news is this?

 

sorry.
can't tell you yet.
it's a secret.

 

Make him wait!

 

Well then, in that case... back to milling

 

ok eric, thats what i thought you would say.

awaiting it is.