B&S #5 Filters

Thanks to all who post here. What a treasure!

I recently discovered that a Brown & Sharpe No. 5 8x24 Precision Grinder at our makerspace (Cincinnati's Makerspace) is missing 6 parts from the return flow path of hydraulic fluid (circled in red in the attached picture of parts). These parts, when present, are located in the top of the machine's base. I've volunteered to remedy this situation. We have local high school robotics club students using the space to build their robots, and we want to return this to service ASAP.

Which way does the fluid flow through pipe 23-2810? a) does fluid enter at the top of the pipe and exit at the notch towards the bottom (prior to being filtered), which means the bottom of the pipe would need to be sealed, or
b) is the top sealed, directing fluid outside the filter, and fluid first enters the pipe at the notch (after being filtered), and exits out the bottom, or
c) am I completely lost?

The Operations and Maintenance Manual I recently found mentions that a clogged filter will cause overflow, which I presume means flow out over the top of the cartridge (above the J slots, see attached pictures). This would seem to indicate that fluid passes through the filter from outside to inside (case "b" above), with only the hydraulic head provided by the height of the fluid in the cartridge (<7", since open to atmosphere) pushing the fluid through the filter? I think this oil is already returning at atmospheric pressure, after lubricating the table ways, and is being filtered to trap contaminants from same, prior to discharging into the base.

Thanks in advance, and stop by if you're ever in northern Cincinnati, Ohio.

I don't know the answer to your question, because I don't have one of these machines and have never worked on one. However I have added an oil filter to my Studer RHU450 cylindrical grinder, so have at least some idea what is going on.

The purpose of this filter is to remove particles from the hydraulic oil of the machine. It is located in the return path, probably just before the oil returns to the sump.

As you write, the filter should probably accept oil from the outside of the filter material where there is more surface area, and then output that oil from the center. Since the parts that are missing include the filter element, it's certainly not doing its job.

Short of re-engineering the filter, or finding a donor machine or replacement original parts, another approach might be to simply replace the filter (with it's replaceable element) with a modern spin-on filter and housing.

On my machine, I used a Wix 51413 spin-on hydraulic filter, and purchased the fitting for it on Amazon for a few Euro. I deliberately bought one WITHOUT a bypass: if it ever gets plugged I want to know it. But you could also buy one with a bypass.

https://www.practicalmachinist.com/...-rhu-450-1960s-343863/index4.html#post3176281

If you have space inside the machine, I would consider such an option as easier than trying to reproduce factory, and perhaps even better, since oil filters have improved in the past decades.

Cheers,
Bruce

I tried to catch texasgunsmith's attention in another thread and point him here. He has a #5 as I recall, and may be able to answer your questions.

I cleared a little space in my inbox, thanks for that.

I'm working now, but later I'll post some pics for you. I don't know off the top of my head. But I have a color illustrated manual that shows the oil flow in a nicely illustrated diagram as i recall.

I'll try to post this evening.

Apologies, I was speed reading at work and missed the fact you had a parts book and Operation manual. Also I hid my book so well, that I have yet to find it. The one I purchased with color flow charts is here, and mentions in the description if you scroll down:

Brown & Sharpe No. 5 Surface Grinder Manual Parts & Ops | eBay

This parts book is slightly different from yours if you notice the part numbers:
Brown & Sharpe Mfg. Co. - Publication Reprints - No. 5 Surface Grinding Machine - Repair Parts | VintageMachinery.org

The pdf:
http://vintagemachinery.org/pubs/2185/5791.pdf

Operation and Maintenance:
Brown & Sharpe Mfg. Co. - Publication Reprints - No. 5 Surface Grinding Machine - Manual | VintageMachinery.org

The pdf:
http://vintagemachinery.org/pubs/2185/5790.pdf

Last page of O & M book, shows basic drawing:



This is actually quite simple. Remember old style engine oil filter canisters for old diesel engines ? The filter was sandwiched between two flat washers, and a spring to keep the washers sandwiched snug to filter.

Same principle here. Two flat washers clamp top and bottom of filter. The pipe you mention, and have circled in red is actually a hollow bolt. Parts assembled in this order: bolt, spring, flat washer with spring centering feature, filter, flat washer, main canister, and last the nut goes on the bottom outside of canister.

Oil drops on top and sides of filter. Leaks to center of filter. Then oil drains out the bottom of hollow bolt. I altered your pick with two orange arrows to show flow:



Edit: The bottom flat washer either clamps the bottom of filter, or goes between canister and nut. But the top spring and washer definitely clamp filter to hold to canister.

This should show the parts assembly direction a little better:

IMO, if you have space for it, better to just add a modern spin-on filter. Here are the two parts that I used, which cost in total about $20. The filter is intended for hydraulic oil and has a 30 bar burst pressure.

KRAFTSTOFFFILTER DIESELFILTER VORFILTER OL fur DIESELPUMPEN KRAFTSTOFFPUMPEN HEIZOLPUMPEN UMFULLPUMPEN zum SUPER-PREIS (Gehause ohne Filtereinsatz/Halterung fur DIESELFILTER/Filterkopfteil) : Amazon.de: Auto & Motorrad

Amazon.com: WIX Filters - 51413 Heavy Duty Spin-On Hydraulic Filter, Pack of 1 : Automotive

[EDIT]

Here is a nice page showing some of the standard parts available for this, and the prices (which are very reasonable).

Rucklauffilter - Hytec Hydraulik Onlineshop

The page is in German but I think the parts and prices are pretty universal.

[second edit]

They have a similar page in English, but with different organisation and poor translations, for example "1.7 bar cracking pressure" means "1.7 bar opening pressure"

Hydraulic Filters: Return Line Filter at your Hytec Hydraulik Onlineshop