Blank off or grind off engine/gearbox mounts when powder coating the frame?

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2WheelsUp

2WheelsUp

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I'm sending my frame, swingarm, and bits to the powder coater next week and have blanked off the mounting holes with nuts & bolts per Old Britt's tech note. I'm found the suggested bolts and washers listed in the note are not exact diameters resulting in mis-aligned washers that float around the hole, and I suspect they will either leave depressed leave rings around many of the holes after it's been painted, or worse, result in some of the mounting washers covering the powder if the washer wasn't large enough or mis-aligned in the hole. While I can certainly attempt to center them, my powder coater will need to do the same when he puts them back on after blasting the frame... doubtful he'll be as careful. No idea whether these areas will more or less disappear once I have things back together or look messy. I've considered just painting the engine/gearbox cradle myself, but I'd really like to have it powder coated. Alternatively, I'm thinking about just letting my powder coater tape off the major areas recommended by Old Britts, in fact you can see pretty deep witness marks to guide them, so it'll be clear where to put the tape. I'll leave the other areas uncovered. Once it's done, I'll go over the mounting points and grind off the powder using a Dremel to the exact size of the washers that will be used. Has anyone tried this latter technique?
 
I've never had anything freshly powder-coated.

This may be too much of a bodge for you... I have removed fixings on the frame, which have shown damaged coating where the washers were. I've smoothed the areas flat (wire wool and wet and dry paper), put foam earplugs into the frame hole, masking tape and Motorcycle News and flashed the area only lightly with aerosol Hammerite smooth black, which matched very well, so you couldn't see it.
 
2WheelsUp said:
I'm sending my frame, swingarm, and bits to the powder coater next week and have blanked off the mounting holes with nuts & bolts per Old Britt's tech note. I'm found the suggested bolts and washers listed in the note are not exact diameters resulting in mis-aligned washers that float around the hole, and I suspect they will either leave depressed leave rings around many of the holes after it's been painted, or worse, result in some of the mounting washers covering the powder if the washer wasn't large enough or mis-aligned in the hole. While I can certainly attempt to center them, my powder coater will need to do the same when he puts them back on after blasting the frame... doubtful he'll be as careful. No idea whether these areas will more or less disappear once I have things back together or look messy. I've considered just painting the engine/gearbox cradle myself, but I'd really like to have it powder coated. Alternatively, I'm thinking about just letting my powder coater tape off the major areas recommended by Old Britts, in fact you can see pretty deep witness marks to guide them, so it'll be clear where to put the tape. I'll leave the other areas uncovered. Once it's done, I'll go over the mounting points and grind off the powder using a Dremel to the exact size of the washers that will be used. Has anyone tried this latter technique?
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Washers drive me crazy! Standard are way loose on the bolt. SAE are tighter but not like the old British washers. So, I have 5mm, 7mm. 8mm, and 10mm. The fit #10, 1/4", 5/16" and 3/8" better and have a smaller OD. They are ideal for the cradle masking. That said, I no longer powder coat cradles. They are barely seen and VHT Gloss Rollbar and Chassis paint requires no primer, is heat, gas, and oil tolerant, and is easy to apply.

You will hate grinding - tried it - extremely hard to do! I tried just masking - takes way longer than the Old Britts method. If you do use the Old Britts method you still should paint the raw spots with a paint brush and a small tin of Rustoleam gloss black or similar.
 
Greg, I tried a can of VHT Rollbar and Chassis spray paint, but it had a low gloss finish. Reading your post, I realized I bought the Satin finish, cans aren't labeled, didn't realize they have a Gloss. I'll pick some up later today and try it. Thanks!
 
2WheelsUp said:
Greg, I tried a can of VHT Rollbar and Chassis spray paint, but it had a low gloss finish. Reading your post, I realized I bought the Satin finish, cans aren't labeled, didn't realize they have a Gloss. I'll pick some up later today and try it. Thanks!
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Look at the white patch on the back/side. They are labelled - I wish better - I've made the same mistake. I repainted my rider without taking it apart. Sanded bare/rusted spots, held cardboard behind the area and painted with some overlap. You can't tell where the original and new paint begin and end so it not really glossy, just right in my book.
 
2WheelsUp said:
I'm sending my frame, swingarm, and bits to the powder coater next week and have blanked off the mounting holes with nuts & bolts per Old Britt's tech note. I'm found the suggested bolts and washers listed in the note are not exact diameters resulting in mis-aligned washers that float around the hole, and I suspect they will either leave depressed leave rings around many of the holes after it's been painted, or worse, result in some of the mounting washers covering the powder if the washer wasn't large enough or mis-aligned in the hole. While I can certainly attempt to center them, my powder coater will need to do the same when he puts them back on after blasting the frame... doubtful he'll be as careful. No idea whether these areas will more or less disappear once I have things back together or look messy. I've considered just painting the engine/gearbox cradle myself, but I'd really like to have it powder coated. Alternatively, I'm thinking about just letting my powder coater tape off the major areas recommended by Old Britts, in fact you can see pretty deep witness marks to guide them, so it'll be clear where to put the tape. I'll leave the other areas uncovered. Once it's done, I'll go over the mounting points and grind off the powder using a Dremel to the exact size of the washers that will be used. Has anyone tried this latter technique?
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BTW, mostly the frame doesn't require masking except where the steering bearings are installed. The areas around the battery box are optional for masking IMHO. The swingarm can be a real PITA if the don't mask inside the pivots and the inside edge of the pivots. I like the frame and swing arm powder coated, I power coat the yokes and front ISO mount in-house and I used to powder coat and now paint the cradle in-house.
 
marshg246 said:
Washers drive me crazy! Standard are way loose on the bolt. SAE are tighter but not like the old British washers.
Click to expand...

Greg,
Norton's and the rest of the British automotive industry originally used imperial washers table 3 heavy on most of the fasteners. The Commando also used large area penny washers in a couple of areas (fuel tank and lower shock absorber washers come to mind). If you would like to use aircraft bolts, imperial washers table 3 light's are useful as well.

I got my imperial washers from Namrick for the restoration of my MGA Coupe. After receiving the washers I realized that the MGA's use a lot of penny washers as well, so I will be ordering more soon.

Peter Firkins
 
My last powder coated Norton frame was a few years ago. I wish that I had masked the inside of the transmission mounts. The coating was too thick and needed to be cleaned up on reassembly. (Never again.)
 
Hurumph ,

On the 61 Bonnie , eventually , it steered well . AFTER it LOST all the paint in the JOINTS .

You could consider theres a degree of elastisity , flex , shuffle , with a CONNECTION with a non ferrous interface ! .

Or Paint in the Connections .

So Bare Metal at the engine cradle to motor & gearbox , Its liikly to steer better , as theyre less liable to shuffle under duress .
So youll need spare footrest rubbers . :oops:
 
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PeterJoe said:
Greg,
Norton's and the rest of the British automotive industry originally used imperial washers table 3 heavy on most of the fasteners. The Commando also used large area penny washers in a couple of areas (fuel tank and lower shock absorber washers come to mind). If you would like to use aircraft bolts, imperial washers table 3 light's are useful as well.

I got my imperial washers from Namrick for the restoration of my MGA Coupe. After receiving the washers I realized that the MGA's use a lot of penny washers as well, so I will be ordering more soon.

Peter Firkins
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Thanks for this. I had no idea that they were still available.
 
I used a dremel on my powder coated cradle and frame, then went back and put a thin coat of paint over the ground off places. Had to make a few small sanding/grinding tools. I planned to use nord lock washers, so sized accordingly. I was mostly concerned with the engine mounting locations and where the swing arm attaches. I haven’t started assembling yet, but hope to soon as my motor and trans. just came back recently. If any further sanding looks necessary I’ll just take it as it comes. I looked at the Old Brits article and found that process daunting.
 
2WheelsUp said:
I'm sending my frame, swingarm, and bits to the powder coater next week and have blanked off the mounting holes with nuts & bolts per Old Britt's tech note. I'm found the suggested bolts and washers listed in the note are not exact diameters resulting in mis-aligned washers that float around the hole, and I suspect they will either leave depressed leave rings around many of the holes after it's been painted, or worse, result in some of the mounting washers covering the powder if the washer wasn't large enough or mis-aligned in the hole. While I can certainly attempt to center them, my powder coater will need to do the same when he puts them back on after blasting the frame... doubtful he'll be as careful. No idea whether these areas will more or less disappear once I have things back together or look messy. I've considered just painting the engine/gearbox cradle myself, but I'd really like to have it powder coated. Alternatively, I'm thinking about just letting my powder coater tape off the major areas recommended by Old Britts, in fact you can see pretty deep witness marks to guide them, so it'll be clear where to put the tape. I'll leave the other areas uncovered. Once it's done, I'll go over the mounting points and grind off the powder using a Dremel to the exact size of the washers that will be used. Has anyone tried this latter technique?
Click to expand...
Argon tape is best
 
@jamesp, I didn't necessarily see blocking off the holes/mounts as hard, rather I found you need exact washer sizes to do a good job without leaving powder lines around the fasteners. I bought the exact hardware list Old Britts identified, and it was disappointing. Even after blocking off the mounting points, the powder coater needs to do a good job masking off the other areas that could be more problematic with a Dremel. I think Greg's idea of painting the cradle and powder coating the rest is probably the safest and easiest way to achieve the outcome I'm looking for given I can match the paint reasonably well.

@KiwiShane, the powder coater has a special heat resistant tape they use, no idea on the brand.
 
With old motorcycles, originality is valuable. When you own one, you are only it's custodian. There is not one Japanese motorcycle which is a classic. A Japanese factory production racer is valluable and an RZ350 is worth having. But none of them are anywhere near in the same class as a Commando. On this forum I have been a bit disparaging. I would not own a road Commando, it would be wasted on me. Just love them for what they are - warts and all. Beauty is in the eye of the beholder. I hate Velocettes, but I once saw a Thruxton that I would die for. Whoever owned it was a fanatic.
Restorations can be recognised immediately. I would never buy one.
 
With my Seeley 850, it looks like a race bike which actually existed, however in itself it has no value as a collectible, except for the fact that it performs well. One of my mates complains when I call it a 'shit-heap'. Everything about it is completely unoriginal. But it looks right. If you know what it is, it is a good thing to own. I will never sell it, because I built it for myself. Some artists do that with their paintings - a painting can be for their own edification.
My Seeley is like my step-daughter's dog I adopted - we understand each other. He was also a pit-bull cross.
 
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acotrel said:
.... There is not one Japanese motorcycle which is a classic. A Japanese factory production racer is valluable and an RZ350 is worth having. But none of them are anywhere near in the same class as a Commando. .....
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You might just be showing your age there! :)

Personally, I would happily own an early 70s Honda CB750, for its looks and sound, let alone what it represents as a motorcycling milestone. We're all different.
 
@acotrel, we are very different, which makes life more interesting, but I agree with you on this point, I build them for myself the way I like them. A this point I have five bikes, all of them look and run like new. My goal is to have every bike I've ever owned in my garage ready to ride, thankfully the list isn't large since my checkbook certainly isn't. They are all different and I ride them all, a lot, so I need to have them to be safe at speed, and I don't want breakdowns, particularly in the mountains where I mostly ride. I don't care about them being collectable or valuable as I will never sell them. I find it incredibly satisfying to walk up and ride off on a machine that is as good or better as the day it came from the factory, whatever that takes as can be seen in the 1978 MG LM1 restoration I did last year. If I can make it look, ride, or handle better with better parts, I'll consider it. I've been riding my older bikes more than the newer ones, a trend that I believe will continue with my Norton once it's finished. Cheers!
 
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