Extending Cylinder when off tractor???

[CHDinCT]

I am modifying a manual angle Kubota snow plow to add hydraulic angling. By way of background, I picked up a slightly used 54" blade from Messick's about two weeks ago for $350. Since the 60" Kubota blade that comes standard with hydraulic angling was s over $1,000, this seemed the obvious choice.

I have ordered the cylinder and hoses I need but will need to take the plow and cylinder to a welder to weld on the cylinder mounts since I don't weld. I can't bring the tractor to him since I don't have a trailer (yet - on my longer term needs list). So, I can show him where I need the cylincder mounts welded on and those can be trialed with the cylinder closed, but, without the tractor along, we would have no way to extend the cylinder to make sure there's no clearance issues, etc. when fully extended ....... unless the cylinder can be manually extended somehow. I just didn't know if you can put the cylinder in a vise, for example, and safely pull out the rod without oil in it. Obvously, we'd have to remove the caps on the hose fittings to let air in. So is this doable or would this score the cylinder from lack of oil in it? Thanks in advance.

By the way, this pic from blackmajicwomen is the inspiration for what I"m trying to accomplish.

http://www.tractorbynet.com/forums/...lade-question-534638-041121-kubota-plow-angle

 

[Ductape]

I see no reason you wouldn't be able to extend, or retract the cylinder as long as air/oil is allowed to escape and enter the ports where the hoses connect. It may take some pushing / pulling. I'd imagine your welder is going to want to have the cylinder in the middle of its throw before he decides where the ends are going to mount....... so that it will angle equal amounts in both directions.

 

[Ken Cunningham]

I doubt that just extending it or retractiing a few times would harm it, but you could just put a few drops of hyro fluid in there and let it coat the tube if it makes you feel better. If the welder has a air compressor you could use a air nozzle with a rubber tip and press it in the ports to operate the cylinder, should work.

 

[CHDinCT]

Thanks for the replies. I had no idea if this would be dangerous or not. Air compressor is an interesting idea. Perhaps put a few ounces of hydro oil in it and then use the compressor to extend/retract the unit would be enough to nail the cylinder hitch positions with no permanent damage.
If anybody thinks otherwise, please chime in.

 

[kennyd]

Thanks for the replies. I had no idea if this would be dangerous or not. Air compressor is an interesting idea. Perhaps put a few ounces of hydro oil in it and then use the compressor to extend/retract the unit would be enough to nail the cylinder hitch positions with no permanent damage.
If anybody thinks otherwise, please chime in.

There is no problem doing it that way.

 

[J_J]

I believe I would use a swivel eye cylinder in that location. They allow a little twisting, and off center mount, like these.

https://www.surpluscenter.com/item.asp?UID=2009092517444130&item=9-7259-10&catname=hydraulic

 

[Wayne County Hose]

A new cylinder will either have some assembly lube or residual oil left in it from pressure testing at the factory. Pull it out and push it in as much as you like. You aren't going to hurt it. You are wise to ask about it. We all know that nobody likes a rod put in and pulled out without some kind of lube.

 

[CHDinCT]

I believe I would use a swivel eye cylinder in that location. They allow a little twisting, and off center mount, like these.

https://www.surpluscenter.com/item.asp?UID=2009092517444130&item=9-7259-10&catname=hydraulic

JJ - I considered a swivel eye cylinder but decided against it due to the need for extra large mounting brackets given the OD of the swivel eyes. I really wanted a one with a x-tube with grease zerk at both ends but couldn't find one with the bore and stroke I was after. Ended up with one just like the pic. But, I have a surplus center swivel eye cylinder with the same bore and stroke as what I bought that I use for a top link. If it turns out I need the extra movement at the pin holes, I'll use that cylinder as I'd like one with a longer extended length for my top link anyway.

WCH -I consider your opinion to be a very informed one so between you, kennyd and the others that replied, I'm feeling confident we can fit this up without the need for tractor generated PSI, and I learned something new too. Thanks.

 

[SPYDERLK]

Thanks for the replies. I had no idea if this would be dangerous or not. Air compressor is an interesting idea. Perhaps put a few ounces of hydro oil in it and then use the compressor to extend/retract the unit would be enough to nail the cylinder hitch positions with no permanent damage.
If anybody thinks otherwise, please chime in.

If the cyl sticks a bit you will get no movement followed by very quick movement to its stop as the pressure reaches an adequate level to break loose from friction. I would suggest using a regulator with the pressure set at just a few psi [2 to 5]. If it moves - good. If not, aid movement by pulling or pushing the ram in the direction the air is trying to move it.
larry

 

[Willl]

If the cyl sticks a bit you will get no movement followed by very quick movement to its stop as the pressure reaches an adequate level to break loose from friction.

This alone is a good reason not to use air pressure, I have seen them break loose quite violently.