OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers New boy saying G'day

G'day,

I am a new boy from God's own country WA Perth.

Have just acquired a Scott Bonnar Model 40 electric and it does not appear to be too shabby for it's age and all parts are present.

I have uploaded some pics (have plenty more) into the pic forum.

My plan is helping my nephew restore it for my brother (his dad) for fathers day.

The cutting surfaces probably haven't been sharpened this century.

The motor requires attention as it barely turns. I am not sure if it is simple (I am an optimist) as new brushes or am I going to have to find a place to rewind it and pay through my eye teeth. Am fairly competent small engine tinkerer but am not electrician but have changed brushes in small power tools and starter motors before.

edit I have managed to get it running by push starting when turning on and runs fine then. The clutch is good and mower moves fast! I think I will clean and redo all electrical connections until where they enter the motor. Apart from doing this I am stumped on what to try next? .

The one part I would love to acquire are at least one new original hand grip but I bet I have Buckly's in getting one of them. If there was enough interest I may be able to have a small run of reproduction handles made but not going to do that for just one grip.

I am on a fixed income and can not afford to go nuts. However, would like to give nephew an appreciation that once upon a time we could make products that lasted, right here in Oz.

Please feel free to tell me that I am dreaming, especially if you can tell me why.

Thanks,

Cam.

Cam's pics < another hyperlink

Insane or Not single choice
	Tell me "I'm Dreamin"
	Piece of cake
	Could be a laugh watching this joker waste time and money
Votes accepted starting: 18/08/12 02:36 PM You must vote before you can view the results of this poll.

G'day Cam!

Welcome to the Forum, Nice Scott-Bonnar! unfortunately I know almost nothing about Reel (cylinder) Mowers... I'd Personally ask DeeJay, He's you're friendly Scott-Bonnar expert, He knows heaps and will be more than happy to help!


Currently, the forum is a little slow but I assure you it perks up in the summer!


Hope you enjoy you're stay

Kori

I don't feel that it's like your dreaming.In-fact I'd like to see it restored as most people restore the petrol engine version.I think it would be great to see an electric one restored.The only thing that I would suggest is that you check the engine and make sure it's all good as if it needed some major repairs could push it past the point of spending more on it than it could be worth.I reckon go for it though.

Hi Cam, and a warm welcome to the OutdoorKing forum.
I will have a go at re-sizing these pics for you as it does make it hard to see your post in the gallery.
I think trying to have this machine restored by Fathers Day (on a limited budget) is a big ask....just looking at the machine, and considering that it is an electric, this is (in my opinion) what would be needed:

(1) The cylinder spun ground and possibly a new bottom blade fitted (depending on its condition now)

(2) The electric motor rewound or repaired....or perhaps replaced if the above is not possible. Just because it will run with a push start does not auger well for a long life or (more importantly).... safe.

(3) Catcher mounts need attention.

(4) I would recommend a complete rewire by a licensed electrician using the latest pvc conduit and electrical fittings ...because of the machines age and condition...Better to be safe than sorry...these things can be lethal.

(5) Definitely replace the rubber grips...the originals you will not find anywhere except on an old machine, as they were discontinued by SB in 1980.

(6) A complete strip, sand blast, prime and repaint.

(7) New replacement set of decals.

(8) Replacement parts for the Model 40 are very hard to come by and no longer made.

With time and money, this machine could be restored, and would be a interesting addition to a collection, but to do it all in under a month nigh on impossible.

Sorry I could not have been more positive, but with an electric, there are no half measures.
Once again Cam,

hi cam ,& welcome to the forum. your electrical problem could be as simple as replacing your start cappacitor. i have bought various electrical powered units from the auction rooms that dont run, ive had a lot of luck with caps , mind you one of my mates is a sparky.caps are cheap if they fix your problem. but dont try any fixes without professional advice/assistance.
lottsa luck johnno.

UPDATE:

On the weekend I established that the motor was not running as it should and believe that I have found the issue (I have heaps of step by step pics too).

As far as I can tell the motor has not lost any of it's magic smoke (you know the stuff, where an electrical device shorts with a whimper or goes pop). Upon investigation it appears that at some time a previous tenant has treated the machine to a bath or decent shower and the inside bottom of the motor housing is quite rusted. As a result of water ingression, one of the centrifugal switch springs corroded through and the switch mechanism cleaned up nicely (no capacitors in single phase motor of this vintage).

I have tried all the springs I had access to but none up to the task. I have also had my multimeter across all the windings and no open circuits present or ultra high resistances.

Fortunately, I have been able to find an old wise motor rewinder who is certain that they have the centrifugal switch springs for the motor and if that doesn't resolve it, they have half a dozen equivalent motors if mine is knackered. I could also buy a brand new drop in replacement motor for less than 70 bucks but there is no fun it that.

I would be interested if the sprockets look serviceable?

Bearings are cheap and easy if needed.

Blade set and sharpen was always on the cards and badly needed. Any recommendations for top notch engineer in Perth would be appreciated.

If anyone has a close up of model 40 catcher brackets (as per my pic) would be most grateful as no shortage of toolmakers or sheet metal workers in my life.

I think that by next weekend (not this weekend) it should all be running sweet. I know my brother will appreciate an un-restored machine in preference to a pretty shiny old thing. Kind of like those guys who shoot their classic autos in primer and lightly spray black on them (ugly in my books)

PS would there be any takers for repro handles as I know just the man in SE Asia to do a limited batch run.

Hi Cam, well mate, you seem to have addressed all my issues, and have a sound knowledge of Ohms Law regarding the electrical issues, so all should be good in that respect. If you can repair the motor, that would be a good result.
Re: the spin grind for the cylinder reel, that should set you back around $70.00-$100.00 eastern state prices plus the price of a new knife-blade (if required). You need to remove the reel and soleplate (complete with the knife-blade attached to the engineer) and he will remove the bottom blade and supply the new one with new screws (if necessary).
The cylinder reel bearing should be replaced in any case, as the reel to bedknife adjustment is critical, and due to their age, they would be unserviceable, considering you just went to the expense of a re-grind of the reel and bedknife.
For the regrind; just contact the greenskeeper of your local Bowling Club and ask who they use....they are usually a great bunch of blokes, and will give you good advice.
All the sprockets look in reasonable condition, and should give good service for a good while yet. (New parts not available, in any case)

Finding pics (especially close-ups) of the catcher attachment points is a problem....Model 40's are very rare on this forum..you may care to post your request in the "wanted" forum, and hopefully, one of our members will see it and know of someone who has one, and post some pics.
Depending on price, I think that there would be a few members interested in the repro 'original' rubber grips, myself included.
Best Wishes,

Thanks Deejay,

Funny thing about where I live, 20 years ago there were over a dozen bowling clubs with 5km, now 2 and only one has turf.

Am talking to old friend in Malaysia right now and he asked me if I god buy an "as new" old grip as a base model, otherwise his grandson will probably use CAD/CAM to recreate it in his modern interpretation.

When you use the term engineer are your referring to an engineering workshop or just a competent mower service shop? The few that I have spoken to here in WA all used the term dress the blade and did not really want to go into what machinery they use to do it. Would hate for an apprentice to have a go at it and take too much meat off the cylinder as pics show it looks like enough metal on cylinder for another 50 years is serviced gently.

Speaking with friend I wonder if there would be market for quality new electric cylinder mowers? Hmmm

Cam, the sharpening of the reel is normally done with a special grinding machine set up for the job. It also has a facility built-in for sharpening the bedknife while still attached to the soleplate. In principle the jobs can be done with a toolpost grinder on a lathe, but the setting up would be prohibitively expensive. Hence you need to go to what used to be called an engineering workshop, and it has to be one that specialises in maintenance on reel mowers. Deejay always refers to the tradesman who operates the grinder as an engineer. Perhaps he does the same for locomotive enginemen.

Bear in mind that the troubled electric motor you have is only a half horsepower one, where the engine-driven version of the same mower had 2 horsepower, which was later increased. Also, that original motor was an Australian-made one that was by no means widely admired. Hence I do not expect you will find your Model 40 to be any great shakes as a lawnmower. In summary it looks to be quite restorable but once restored, it may not be able to climb an incline or mow thick grass. If you try, it will presumably burn out. For a collector's piece that need not matter, of course.

Wow, I'm in a critical mood this morning. Oh well, it suits my chosen nickname.

Update Day 4:

Have visited 4 bowling clubs, which still have at least one turf green. They are getting very thin on the ground and only one of those clubs did not have major broad leaf weed issues. I can only guess that they are waiting till slightly warmer weather to poison those nasties.

I also visited more mower shops. Very surprised that reasonable restoration Model 45s start at about $950 retail. I did not come across a single 45 (no matter the price) that was in the league of many members� machines. Did not see one example where handles were re-chromed.

Sand blasting and electro-plating (chrome work) wildly varied in price, example quality and professionalism of proprietors. One valuable nugget of information confirmed by multiple sources was that there is only one way to remove chrome so that any future coasting adheres properly (whether paint or powder coating) is reverse electrolysis. Sand blasting may appear to remove all visible traces of chrome but full bonding cannot be achieved with any trace of previous chrome remaining. Sure it may look good for a while but many claim is that it won�t last anywhere near as long as elctro stripping the substrate before further treatment, even sandblasting .

I find it hard to believe that so many non-related entities would agree. Even one industrial sand blast (who wanted $360 per hour of �nozzle time�) said the same thing.

I have found 2 �engineers� that I would be happy to do business with for spin grinding and static blade sharpening. Surprise, surprise they are both getting on in years and happily showed me their tools of trade. I am confident that both would do a fine job to give this machine, another 50 year of life without destroying all the meat still on cylinder. There is one more who I spoke to and look forward to meeting, that has come highly recommended and has coincidentally just acquired a Model 45 electric for his own collection.

I have settled on an electro plater, who if does a great job, I will be happy to recommend as a potential resource for WA restorers, as he appeared honest and professional with exceptional examples of his craft. These weren�t his show pieces but stuff sitting on shelf awaiting customer collection.

Sand blasting has been sorted too (stiff bickies for my brother/nephew�s father who likes whatever the bloke equivalent of �shabby chic� is, ala primer finished classic autos). Have found and industrial blaster who will blast all I take to them for a carton. Also happy to provide details via PM if they work out OK.

1. I am in need of advice for tomorrow�s progression. Is powder coating really better than painting on a properly cleaned and primed cylinder surface?

2. What colour hammertone do other use for their 40/45 restos, and do you rust treat (ie ranex) after blasting and before you use the hammertone manufacturer recommended primer?

3. I have until now, had great success applying hammertone finishes via brush (even the cheapest ones have done same job if applied within recommended temp range.

4. The repro grips are potentially a goer, providing I can source the best example possible as a prototype. Am even prepared to leave $100 deposit with a sponsor who could let me have it for a while (remember, I am outsourcing manufacturer to SE Asia and things work on rubber-time).

Am estimating that I could provide 50 pairs as this would be minimum break-even point, and at only ~4 times the price the ones at existing retailers, who are selling Malvern Star bike grips as replacements.

5. Would really appreciate a close up pic of an original Model 40 catcher�s lugs.


Dinner time (back after dinner),

Later,

Cam.

PS before my dinner is getting too cold. Mr Grumpy are you certain about hp equivalencies between electric motors and Internal Combustion Engines? As I have trouble maintaining a reasonable walking pace behind the half hp motor, and I am almost six and a half feet tall? Plenty of torque in that poorly thought of and running motor.

Cam, I'll leave all your other issues to Deejay, our Scott Bonnar guru, and only comment on the horsepower point.

Shaft horsepower, whether in relation to an internal combustion engine, an electric motor, or any other source of mechanical power, is a concept invented by James Watt, the steam engine pioneer. He measured the amount of work his pit pony could deliver when hauling an ore car up a slope, decided rather arbitrarily that a pit pony could do half as much work as a full sized horse, and concluded that the power of one horse was 33,000 ft lbs-force per minute. Subsequently a more convenient metric measurement of power was established and named after Watt. It turns out that 748 Watts equals one horsepower. So, your electric motor is rated at 374 Watts of output power. It will consume more electricity than that, due to losses. Note also that electric motors have a power factor that is quite a long way from unity, so multiplying input Volts by Amps will give you a much larger number than the shaft output power of the motor.

To be fair, the manufacturers of mower engines have traditionally used a test procedure for measuring horsepower produced that might be described as sympathetic to their desires for high advertised horsepower numbers. However while this might increase their power ratings by about a third, it does not enable a half horsepower electric motor to compete with a 2 horsepower internal combustion engine.

Your little half-horse motor has the same output as a small bench-type electric drill - a slightly beefier home-use bench drill would be 3/4 hp. Of course industrial drills are more powerful than that.

Reel-type mowers are more efficient and therefore use less power than rotary mowers, excluding the power used in propelling the heavy reel mower up slopes. Generally, 18-19" rotary mowers have from 3 to 5.5 hp, with the more modern ones closer to the top of that range. Small home-use reel mowers up to 17" made from say, 1970 onward usually have from 2 to 3.5 hp, but I can't recall a 2 hp one made later than the mid-1970s. Deejay will be much better informed than I am on that subject. (The archetype of 2 hp reel mowers was the fairly early SB45 that used the Briggs 60102 engine).

If your electric SB45 is cutting well-maintained grass on level ground, half a horsepower should be sufficient. If you hit some strongly-growing summer kikuyu, or head up a slope, I think the outcome would be rather different. However as long as it does the job for you, that old Crompton-Parkinson has the virtue of being the original motor SB fitted to your old, collectible mower.

I'd be very keen to grab a couple of pairs of grips if you do end up going a head.

I don't think my current grips are in great condition...well not better than the ones in your photos. I will however double check.

Dan

UPDATE

Friday had most of the parts where they needed to be, waiting for the yay or nay from the motor re-winder and was in the process of buying all new bearings when I got a call from the re-winder. It was unfortunately a nay (my multimeter work was apparently not as thorough as theirs )and their inventory of vintage 56 Frame motors were all three phase. I could buy new single phase 1hp Frame 56 for just over $300 at mates rates (Mr Grumpy, took your power rating into consideration) and haven't found cheaper especially for Aussie built with 2 year warranty.

I was ready to part the beast out, to contribute towards the cost of a more restorable Model 45.

Saturday morning was heading out and overnight the fairy motor godmother left a Frame 56 half hp motor (complete with switch gear) on front verandah.

Too bad that I had collected my bits and pieces from the blaster, electro plater, and powder coater on Friday arvo. Just glad didn't hand over the extortionate amount for the double row ball bearing that the last place I was at managed to force to bits and pieces and were not able to re-assemble (pretty damned cheesed off about that as no other bearing place tried to break bearing).

So, Saturday morning the plater, powder coater and blaster were closed. I had to make do with what was available to me and crack on with the resto.

I managed to source some Dark Green Hammerite Hammertone paint, that I have used with great success in the UK and SE Asia within the last 2 years. I also bought a flap disc for the tiny grinder I had access too. Less than spectacular results were achieved with application of this paint by brush (unlike UK and Asia), not sure if starting from bare metal surfaces or more likely that I over stirred the paint prior to application. Used exactly the same product on my front door and security grill in Malaysia and many people asked where I got the metal door from? The model 40's deck, side plates and front roller guides are a disgrace (although stripped, washed with detergent, water and then wiped down with wax& grease remover). There is only a patch of about 3 square inches that look hammertone. I am pretty certain I over stirred it.

Could take back to industrial blaster but might be more than a bit unfair considering paint wont have cured fully and likely to make mess for them.

One trick (shortcut) I discovered from Mr Google was that water on aluminum foil really does clean up the most rusted chrome. The chrome bits will all be back for plating after fathers day but I am blown away with the results as one of the bars was more surface rust than chrome. It is now shiny (enough) again and I haven't even touched it with a metal polish for protection. Perhaps this is good enough for a mower stored under cover once polished for protection.

Re-taped the baring surfaces and gonna drop all parts off to blaster tomorrow but will give them fair warning that paint isn't hard yet and leave it upto them if the want to take risk of contaminating their media with unset Dark Green Hammerite.

All new nuts and bolts have been sourced. Said to the guy at fastner place that I was one of "those customers" who came in with a very small order but a large variety of parts and that would be PIA to pick from shelf. They were very good about, it.

More updates and photos available but things I must do.

Night,

Cam.

Having an Australian-made motor does not seem to me to be a functional advantage, but is very much worthwhile in collector-value terms if it is similar to the original motor. (My opinion on Australian-made electric motors, when they were made, is that they were a bit worse than the other electric motors made in those days, which by and large were woeful.)

I suggest you stay away from the merchant who ruined your double-row self-aligning bearing in future. Remember, that has to be a self-aligning bearing: a deep groove ballrace whether single or double row is useless for the purpose. The later, Rover-built 45s did use single row self-aligning bearings, and these were more or less successful.

Would these grips have been standard across the whole SB range eg Diplomat 430?

Hi Kempe, I have just checked the Scott Bonnar product range of 1974-75 and they have the original grips mentioned here....
However by 1976 when the Diplomat 430 and 590 were rolled out, these rubber grips had disappeared and had
been replaced by round ones, right across the whole range, without any SB logo.