How big of cylinder do I need?

[scootr]

Hello - I need advice on how big of a hydraulic cylinder I need to convert my 84" rake from manual to hydraulic operation.
Is one cylinder sufficient or should I use 2 , 1 on each side? Thank you

 

[ROUSTABOUT]

About yay long and so big should be just about right.

 

[MtnViewRanch]

Hello - I need advice on how big of a hydraulic cylinder I need to convert my 84" rake from manual to hydraulic operation.
Is one cylinder sufficient or should I use 2 , 1 on each side? Thank you

Typically for this type of application, a 3" dia cylinder with a 1 1/2" dia rod is what I would recommend. Without actually laying it all out on the implement, probably a 10", 12", or 14" stroke unit. The longer the stroke, the easier it is to make fine smooth adjustments.

 

[Vigo327]

I imagine a rake is a pretty forgiving app for this because you'd probably have a hard time damaging a cylinder before you just bent or broke the rake tines instead.

Cylinder stroke and bore would both affect the sensitivity, but since this is such a low duty cycle you could always put an adjustable restrictor inline too, if you happened to already have a cylinder you wanted to use and it ended up too fast. Either way, you have to match your attachment points to the travel you have,but attachment points might dictate the cylinder stroke more so than the other way around. So the first thing is figure out where and how you could attach the cylinder, and see what kind of travel it would need there to get the right amount of rotation on the rake.

 

[scootr]

Good advice. I've got the rake on the tractor now so I'll try to figure out the throw I'll need. Obviously the closer to the pivot pin I mount the less throw i'll need -
I'm thinking the load is minimal to move the rake. The real load is holding the rake in position when the rake snags a rock or a pile of earth

I guess the geometry would be close to a dozer blade set up ?

 

[MtnViewRanch]

Just look at a rear blade with hydraulics. That gives you an idea of what to do.

 

[scootr]

Just look at a rear blade with hydraulics. That gives you an idea of what to do.

Thanks for the link. I see you make top link cylinders. How much size or pressure do think is reasonable for this?

 

[MtnViewRanch]

Typically most off the shelf cylinders are rated for 3000PSI. I personally only use and recommend welded cylinders.
I am not a fan of tie rod cylinders.
Most of the utility tractors are set up around 2500PSI plus or minus.
I recommend a 3" dia cylinder with a 1 1/2" dia rod for this application, but that's just me.

 

[scootr]

With the rake square to the boom I marked a point on the 3pt frame and on the rake frame and swung the rake to 45º left and right.
I need 27" short and 36" long. So a 9-10 inch stroke would do.

 

[nybirdman]

I would think a snow plow set-up would work.

 

[MtnViewRanch]

With the rake square to the boom I marked a point on the 3pt frame and on the rake frame and swung the rake to 45º left and right.
I need 27" short and 36" long. So a 9-10 inch stroke would do.

A few pictures of your rake would really help. There are various designs for this stuff. It sounds like you have a short boom if you are looking at using the 3pt hitch mount as a base mount for the rake angle cylinder mount.


A std clevis end welded cylinder with a 10" stroke is 20 1/4"- 30 1/4"

A 12" unit would be 22 1/4"- 34 1/4".

 

[scootr]

Sounds good - I'll post pics in the AM. Thank you

 

[LD1]

Any pics yet Or decided on what cylinder to use?

 

[scootr]

I can get some before pics today and post em later. Thank you

I was looking at these cylinder. I need 9 inches minimum of stroke ideally 27 x 36 overall.

https://www.tractorsupply.com/tsc/product/chief-3-in-bore-x-18-in-stroke-125-in-rod-dia-chief-at-alternative-to-tie-rod-cylinder-1307942

https://www.amazon.com/Hydraulic-Cylinder-Welded-Double-3-5x12/dp/B00SA2OYCK/ref=sr_1_2_sspa?crid=1112EYPE6R6OR&keywords=hydraulic%2Bcylinder%2Bdouble%2Baction%2B12%22%2Bstroke&qid=1666275138&sprefix=hydraulic%2Bcylinder%2Bdouble%2Baction%2B12%2Bstroke%2Caps%2C225&sr=8-2-spons&th=1

 

[scootr]

Sorry for the delay. A snow plow application sounds similar. FYI I tried the rake on the gravel road and I liked it vs the box blade. So I will pursue this mod.
Nvrmnd the wheels pictured. I'm in the process of putting on some larger adjustable gauge wheels. The BH rake is 84 inches

 

[davedj1]

The closer to center you mount the cylinder on the rake the shorter the stroke can be. Can you find a pair of single acting cylinders from an old snow plow and mount one on each side and operate them like one DA cylinder.

 

[scootr]

I finally pulled the trigger on a double action 3" x 1.5" rod cylinder with a 12" stroke and 1" pins

Product Details​

The Chief 3 in. Bore x 12 in. Stroke WC Welded Cylinder is a high-quality welded hydraulic cylinder with a strong forged steel base. Made for when space is limited, this hydraulic cylinder model has a screw-in gland that reduces the cylinder profile by replacing the collar style gland. It will provide added strength to agricultural implements, compact construction and transportation equipment, as well as waste/recycling applications, and the base end clevis extends out 2 in. to ensure greater swing radius and maximum flexibility.

• Intended use: double-acting applications
• Piston: ductile iron
• Gland: ductile iron
• Tube: precision-honed steel
• Rod: hard chrome-plated
• End mounts: ductile iron female clevises with pins and clips included
• Tube seals: Buna O-ring
• Rod seal: deep polypak with B-lip design
• Rod wiper: urethane, snap-in
• Piston seal: Hallite 755 for prolonged wear resistance with wear ring
• All seals: manufactured to US specifications
• Functionally tested and pressurized to 1.5 times the normal working pressure to ensure performance reliability
• Welded hydraulic cylinder with SAE O-ring ports that allow for easy hookup
• Has a 3,000 PSI operating range
• 3-year limited warranty
• Measures 20.25 in. retracted and 30.25 in. extended
• Individually poly bagged hydraulic cylinder is easy to transport
• Column load: 21,200 lb.
• Pin diameter of 1in. and rod diameter of 1.5 in.

 

[scootr]

This thing arrived and all I can say is this cylinder is huge! 3" looks like 2 times overkill. 1/2 lines? Can I run 3/8ths lines There really is no load turning the rake on it's pivot.
What do you all think. Will 3/8ths lines about 4ft long from the quick attach be okay?

 

[rswyan]

The smaller the lines, the slower the cylinder will respond.

IIRC, I used 1/4” lines on mine but the cylinder bore was smaller (maybe 2” ?) than the one you’re using.

Mine was plenty fast enough.

 

[scootr]

Thanks for your reply. Right now I'm thinking 3/8 lines