Heavy contact or not?

I could get myself into all sorts of trouble trying to answer your questions  but this may be of interest

https://www.dropbox.com/s/wq30i6g9cuphvnn/TORO%20reel%20mower%20theory…

Very informative, I think I'll need two reads!
 

thanks Angus,

Will

I have had a lifetime in the Garden Machinery Industry since 1963, Supplying Professional Turf Equipment exclusively from 1973 & my last position was as UK & USA/Canada Territory Manager for one of the top British manufacturers of Cylinder Mower Sharpening Systems.   www.bernhard,co,uk    Express Dual.  

I also worked for a top 36 hole Golf Club before I retired completely, sharpening their 100+ cutting units regularly & playing members noticed the difference on the course too.

In the USA we regularly sharpened & set up Golf Greens mowers with Zero Contact for Demonstrations, Seminars & for Major Professional Golf Tournaments. Always with Zero Contact (2 Thou clearance). Yes I was one of the guys that helped make the pretty stripes on your TV screens & worked with some major Golf Course Maintenance teams for their big events. It is amazing how much difference a sharp, clean cutting mower makes to a lawn's appearance & health.

Practically however, on our older domestic lawnmowers a very light contact cutting set-up, is probably the best that you can achieve unless you re-sharpen about every month or so. When you set your hand mower to run contact, you will notice that it will take a lot more effort to push it, because the cylinder is acting as a brake, rubbing the B/blade. The same can be said for your engine on the powered mower. So setting it for Zero or Minimal contact is a good idea, assuming it will still cut grass.

With the Suffolk Punch & Ransomes Marquis type mowers, they have a centrifugal clutch, so running a little light contact will help the mower stand still when idling & slow the machine down for the turns. When these machines were made 40 to 50 years ago the sharpening was all done on less accurate lathe type grinding equipment & often the B/blade ends were packed with shims to get them to cut evenly. So a light contact was normal & would still be acceptable today.

Back lapping is almost a waste of time because all you are going to do is bed the Cylinder & B/blade faces together making it so that running contact is your only option.

"MY TOP TIP", is to get a good engineers file & pass it across the front "vertical" face of the B/blade, introducing a light burr (sharp edge). on the top face. This is a cheap & easy way to keep a domestic cylinder mower on cut, providing you have a reasonably sharp cylinder.

I am not going into Relief grinding as that is for heavy Professional Machinery, it is an American practice & not relevant to our older UK built domestic lawnmowers. "I could teach you how to do it but would probably have to shoot you afterwards", or myself.

Just a little bit of advice from an "Proper Expert" sharpening guy ???  Peter Hampton

I mostly agree with all of that, but backlapping does have its uses, however it is much overused. I personally never thought much about relief grinding, it wasn't really needed on the type of cylinders I ground, Toro GM SPA units for instance. It only had its place on old towed gangs and only when they were 'low' in the tooth.

You might have seen the results of  some of my work when the open was held on the north west courses and the company I worked for held the Toro franchise. At that time I used to know the Bernhards rep fairly well, but, for the life in me, I cannot remember his name, Colin ??, I seem to remember that he went of to the USA as well.

I used Duals & Anglemasters for most of my working life, but have also used BSL's and Jupiter's as well, in fact I have the dubious honour of telling Eric Hunter his Jupiter was a good cylinder grinder, but an awful bottom blade grinder, by the time I had setup and ground one Toro SPA bottom blade in the Jupiter, I could have ground all three in the Anglemaster and that was before the automatic traverse was available.

If I say the name 'Theo', do you know who he is ?

Bob, the lifetime engineer who looked after our local golf course equipment always told us that on better machines (Ransomes Hahn LTD 500 for instance, three 12 blade cylinders with hydrostatic power and lift) the blades didn't need to touch each other at all, he said that all they needed to do was "crease" the grass and the centrifugal action of the cylinder acting as a fan would expel the grass, this was in 1980/81. I often still wonder if blades do touch does friction produce heat and slightly expand both bottom blade and cylinder eventually? Or perhaps so much grass passing through has a cooling effect?

I often still wonder if blades do touch does friction produce heat and slightly expand both bottom blade and cylinder eventually? Or perhaps so much grass passing through has a cooling effect?

Those  who have used old wheel driven trailed gangs will know all about that. If starting early with dew on the grass, set them on the tight side to get a clean cut but when things started to dry out , first tea break or staybit time in Marsh language, slacken them off. Fail to do so and the cylinders might lock up with the wheels doing the same and leaving furrows in the turf.

[quote]on better machines (Ransomes Hahn LTD 500 for instance,[/quote]

Would this be the machine that got touted about the country, laughed at, then got painted green and had Ransome decals affixed and then got touted around the country again, this time to "isn't that great" ?

The Hahn was rubbish, all electric clutches, belts, flexible drives and a hydrostatic drive system similar to a Wolseley Clearway. It is my opinion, this is when Ransome's started going downhill.

In the 1970s The Ransomes Hahn was a joke but Ransomes seemed to sell it well, mainly because they were well supported with Dealers. It was built in America but never sold over there.  At that time I was demonstrating & selling Jacobsen Mk1s (with the funny little wheels) & then Mk2 Greens Kings. against The Hahn & Toro. The Hahn had flexible drives (like Tarpen) to the cutting units, (2 units being dragged & 1 unit being pushed along), so the unit being pushed had to be set slightly higher (1 old penny) to equal up the 3 cuts. The difference could still be seen though. I was covering the south of England at the time & we often had to demo against the Toro & the Hahn in front of a committee. (I had also sold Toro around Surrey in1969, before they had a triple).

I used to try & get into a golf club a week before a committee demo, train & let the greenkeepers use my Jacobsen cutting all the greens, then on demo day he would be happy to drive my Jacobsen on the demo, but would not use the others. It sold a few machines for me, funny when the Golf Club Chairman was drinking with Ransome reps in the bar & came out to ask me to come back next week with a new machine, LOL.

I have several of the earlier 2 wheeled Ransomes Overgreens triple mowers in my collection. 1935 to 1959 (3 different models) all using Ransomes 16 inch Certes hand mowers pulled like gangs. They are fun machines to use & could also be used with a 30 inch Gang mower & Sisis or Pattisson Aeration attachments, I have those too. So Triple unit mowing on golf greens was not a new idea in the1970s at all.

Zero contact is still the best way to set any cylinder mower, if you can do it, in my opinion, but if you have no other option then use a good file on the front edge of the B/blade after back lapping. Think, if you are  back lapping for more than 10 minutes, it really needs a proper sharpen. "Being cheap is not always saving money".    I know nothing I have only been doing it for 55 years. Peter Hampton

In its defence I can only say that I used ours three days a week to cut the greens in the cutting season and no doubt due to Bob's diligence it did do a good job, at least we never had any complaints! I thoroughly enjoyed using it and I actually used to sing whilst mowing, something you don't often hear nowadays, I thought the noise was drowning me out, but the head greenkeeper did ask me about why! Happy days.

The Hahn had flexible drives (like Tarpen) to the cutting units, (2 units being dragged & 1 unit being pushed along), so 

Spiral wound and handed. Fit the wrong one and it would be an expensive unravel.

Some interesting discussion here re cylinder/blade settings, along the lines of setting the cut with a two thou clearance I was once shown a very simple method of achieving a clearance cut by using two strips of printer paper placed together. The idea being to cut the top paper cleanly and to fold the second against the bottom blade. Ray.