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t ingermanson said:
View attachment 113145

A whole lot of effort to replace an oil tank with holes, to then go and drill the new one full of holes. A bit of a leap of faith on my abilities that I hope doesn't come back to bite me.

Everything is roughed up and ready to bond in the spigots , plumbing, and fittings:

View attachment 113146

Weird holes and irregular edges to let the fiberglass and resin grip the fittings. 6061 Aluminum is notoriously difficult to bond, due to its almost immediate oxidation, so there was a bunch of furious sanding and then painting on the resin ASAP. Only the two large spigots are aluminum, the other fittings are stainless, and all threaded holes are blind. Any part that was a fitting for anything that's going to get something threaded in and tightened, had a backing plate that ran up against the adjacent wall so there's a far lesser chance that the fitting will come loose from the tank. Everything was bonded in after being slathered in a resin and cab-o-sil mixture (which is ground fibers) to fill in the gaps of the holes and edges because resin alone is very brittle and weak. A few layers of fiberglass laminated on over the cab-o-sil, and 24 hours of dry time...

I'm contemplating adding a plug to the bottom of the tank in order to more easily drain the tank below the outlet filter. These tanks are a real pain to get in and out, and anything to make life easier seems worthwhile, especially when it's removing the dross oil from the system.

Seems like I should, but it also seems to be tempting fate. What do you think?
Click to expand...
I think, soft durometer rubber mounts are required.

Also, I think fiberglass will be more problematic than aluminum.

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com


JMWO



Viewer Discretion Advised. Or, A Fool and His Money Are Soon Parted.


Putting esthetics ahead of function, all the weld reinforcement has been removed.
Viewer Discretion Advised. Or, A Fool and His Money Are Soon Parted.


The failure is not surprising.
 
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concours said:
I think, soft durometer rubber mounts are required.

Also, I think fiberglass will be more problematic than aluminum.
Click to expand...
I think Dave Degens went from aluminium oil tanks to fiberglass tanks because the aluminium ones were prone to cracking?
 
baz said:
I think Dave Degens went from aluminium oil tanks to fiberglass tanks because the aluminium ones were prone to cracking?
Click to expand...
No knowledge of these particular bike.😞

BUT, I have a half century of experience with vibration, failure, cracking, fabrication.🍻

The good news is, the laws of physics care not what name is on the badge, or any of the lineage.

Just trying to save misery. I do need to remember that for some, this stuff is therapy.

Rubber mounts need not be complex, expensive or store bought. A box corner style bracket with rubber glued in comes to mind for the box shaped tank above.

Then again, I KEPT the bottom stud on the Commando, and modified it to work at it's intended purpose.
A4E19130-6A2C-4583-8770-8AD9570EE0C5.jpeg


Oil tank repairs... let's see 'em

I removed the rear tab, after the second time it cracked. I came up with a two piece rear mount that clamps on to the filler neck. I wanted to include a picture of this, but it just doesn't show up in a photo very well. Take steel tubing about the same size at the filler neck. Cut off a...
www.accessnorton.com www.accessnorton.com





I'll get my coat🤣
 
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concours said:
No knowledge of these particular bike.😞

BUT, I have a half century of experience with vibration, failure, cracking, fabrication.🍻

The good news is, the laws of physics care not what name is on the badge, or any of the lineage.

Just trying to save misery. I do need to remember that for some, this stuff is therapy.

Rubber mounts need not be complex, expensive or store bought. A box corner style bracket with rubber glued in comes to mind for the box shaped tank above.

Then again, I KEPT the bottom stud on the Commando, and modified it to work at it's intended purpose.
View attachment 113153





I'll get my coat🤣
Click to expand...
https://www.oldbikemart.co.uk/dave-...ognised as one of the,and 1970 as a privateer
He's been around a while and still doing it 👍👍
 
concours said:
I think, soft durometer rubber mounts are required.
Click to expand...
Yes. Used those same mounts (even from McMaster) for the old one. The softest durometer ones. Covered the table it sat on with the softest durometer rubber I could find. Still broke. Aluminum just has that fatigue life that fiberglass does not. I'm hoping, anyway.

The mount you've got is more or less what the Manx Elephant's Foot tanks use, but in the opposite direction, with tunnels coming up through the tank, through which studs pass. Sits on a rubber pad and held in place by those studs. Don't tighten them down too much!!!

I'll be using the same approach as the old tank, but I found some softer rubber to cover the table with. I could also bare some responsibility (duh...) with the rubber o-rings used on the bobbins. Maybe too much pulling down into the table with too thick or small diameter ring. I'll have to do some experimenting.

I know that TAB2 used relatively thin .060" sheet. I'm certainly no expert in aluminum bodywork, but a friend who is, says that that's very thin to use when grinding the seams. Most folks use .080".

Thanks for your input. There's a lot of valuable experience here.
 
Triton Thrasher said:
My 45-year old Unity Equipe fibreglass central oil tank is tough as old boots.
Click to expand...
Yes! I've repaired a handful of those old tanks over the years. It seems they really take a lot of abuse before they die. Most of the time, the fittings are ripped out, but the tank's oil-carrying integrity is still good. They're like 1/4" thick at the thinnest spots. Definitely made to take it.
 
I neglected to show the mold, so here it is:

IMG_3673.jpg


The flaky stuff is the mold release called PVA. This pic was before I rinsed it off. You can see the aluminum strips I added to either side of the seam. Those will be coming out. More trouble than they are worth. I was expecting it to be more difficult than it was to laminate inside, once the halves were together, but it wasn't a biggie.

When I made this mold, I hadn't used this epoxy resin before. I made a couple small parts to see how it acted. Glad I did. I learned that it's got a much longer drying time than polyester resin, and it doesn't chemically bond in the same way by softening the under layer, so it's much more likely to pull up in a tight radiused corner than polyester, known as bridging. The upside is you can laminate all your layers at once, unlike polyester, because there's no heat created that can wreak havoc on the lamination. You can laminate more in one go, but it takes way longer to dry, so it's a give and take. The best part about this epoxy is there's virtually no fumes! Polyester resin is gnarly. It stinks up the outside.

After those couple little projects to get a feel for the epoxy resin, I had to go back into the mold and add that black tinted resin and cab-o-sil to the inside corners to build up the radius to avoid bridging, then had to sand them all smooth. More tail chasing, but the result was good, faster and less work than a new mold.

Here's all the fittings bonded in. I think I might lay in a couple more layers after @Triton Thrasher reminded me how burly those Unity tanks were/are. A bit more work to seal those holes is worth the weight. After the extra layers, I'll lay a fillet of JB Weld around the threaded bosses to make sure they're sealed, particularly the ones below the oil line.

I decided to put the return line at the back corner. I've got an oil filter that sits below the tank, and the routing is pretty onerous. Going to the back cleans up that tight area and allows much more linear room to get the same job done. Also, one less hole below the oil line. I'm putting the return flow restrictor into the hose splitter to the rockers that will sit right below the elbow into the tank. I'm using a run-of-the-mill 1/8" NPT hose fitting. It will be easy to change hose size should the motor ever change.

IMG_3670.jpg


IMG_3668.jpg


No one has piped up about the potential drain plug on the bottom. What do you reckon? Worth the risk? Not sure how I'd do it. It would need to have a permanently mounted hose as to not spew oil over everything below when draining. And with the hose in place, where/how would you add the plug/tap? A ball valve seems way overkill. Maybe just a hose fitting with a bolt into the end? Hmmm...
 
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t ingermanson said:
I neglected to show the mold, so here it is:

View attachment 113170

The flaky stuff is the mold release called PVA. This pic was before I rinsed it off. You can see the aluminum strips I added to either side of the seam. Those will be coming out. More trouble than they are worth. I was expecting it to be more difficult than it was to laminate inside, once the halves were together, but it wasn't a biggie.

When I made this mold, I hadn't used this epoxy resin before. I made a couple small parts to see how it acted. Glad I did. I learned that it's got a much longer drying time than polyester resin, and it doesn't chemically bond in the same way by softening the under layer, so it's much more likely to pull up in a tight radiused corner than polyester, known as bridging. The upside is you can laminate all your layers at once, unlike polyester, because there's no heat created that can wreak havoc on the lamination. You can laminate more in one go, but it takes way longer to dry, so it's a give and take. The best part about this epoxy is there's virtually no fumes! Polyester resin is gnarly. It stinks up the outside.

After those couple little projects to get a feel for the epoxy resin, I had to go back into the mold and add that black tinted resin and cab-o-sil to the inside corners to build up the radius to avoid bridging, then had to sand them all smooth. More tail chasing, but the result was good, faster and less work than a new mold.

Here's all the fittings bonded in. I think I might lay in a couple more layers after @Triton Thrasher reminded me how burly those Unity tanks were/are. A bit more work to seal those holes is worth the weight. After the extra layers, I'll lay a fillet of JB Weld around the threaded bosses to make sure they're sealed, particularly the ones below the oil line.

I decided to put the return line at the back corner. I've got an oil filter that sits below the tank, and the routing is pretty onerous. Going to the back cleans up that tight area and allows much more linear room to get the same job done. Also, one less hole below the oil line. I'm putting the return flow restrictor into the hose splitter to the rockers that will sit right below the elbow into the tank. I'm using a run-of-the-mill 1/8" NPT hose fitting. It will be easy to change hose size should the motor ever change.

View attachment 113171

View attachment 113172

No one has piped up about the potential drain plug on the bottom. What do you reckon? Worth the risk? Not sure how I'd do it. It would need to have a permanently mounted hose as to not spew oil over everything below when draining. And with the hose in place, where/how would you add the plug/tap? A ball valve seems way overkill. Maybe just a hose fitting with a bolt into the end? Hmmm...
Click to expand...
I would not add one. Not really needed and added risk of failure .
 
t ingermanson said:
I neglected to show the mold, so here it is:

View attachment 113170

The flaky stuff is the mold release called PVA. This pic was before I rinsed it off. You can see the aluminum strips I added to either side of the seam. Those will be coming out. More trouble than they are worth. I was expecting it to be more difficult than it was to laminate inside, once the halves were together, but it wasn't a biggie.

When I made this mold, I hadn't used this epoxy resin before. I made a couple small parts to see how it acted. Glad I did. I learned that it's got a much longer drying time than polyester resin, and it doesn't chemically bond in the same way by softening the under layer, so it's much more likely to pull up in a tight radiused corner than polyester, known as bridging. The upside is you can laminate all your layers at once, unlike polyester, because there's no heat created that can wreak havoc on the lamination. You can laminate more in one go, but it takes way longer to dry, so it's a give and take. The best part about this epoxy is there's virtually no fumes! Polyester resin is gnarly. It stinks up the outside.

After those couple little projects to get a feel for the epoxy resin, I had to go back into the mold and add that black tinted resin and cab-o-sil to the inside corners to build up the radius to avoid bridging, then had to sand them all smooth. More tail chasing, but the result was good, faster and less work than a new mold.

Here's all the fittings bonded in. I think I might lay in a couple more layers after @Triton Thrasher reminded me how burly those Unity tanks were/are. A bit more work to seal those holes is worth the weight. After the extra layers, I'll lay a fillet of JB Weld around the threaded bosses to make sure they're sealed, particularly the ones below the oil line.

I decided to put the return line at the back corner. I've got an oil filter that sits below the tank, and the routing is pretty onerous. Going to the back cleans up that tight area and allows much more linear room to get the same job done. Also, one less hole below the oil line. I'm putting the return flow restrictor into the hose splitter to the rockers that will sit right below the elbow into the tank. I'm using a run-of-the-mill 1/8" NPT hose fitting. It will be easy to change hose size should the motor ever change.

View attachment 113171

View attachment 113172

No one has piped up about the potential drain plug on the bottom. What do you reckon? Worth the risk? Not sure how I'd do it. It would need to have a permanently mounted hose as to not spew oil over everything below when draining. And with the hose in place, where/how would you add the plug/tap? A ball valve seems way overkill. Maybe just a hose fitting with a bolt into the end? Hmmm...
Click to expand...
Looks great!
 
t ingermanson said:
I neglected to show the mold, so here it is:

View attachment 113170

The flaky stuff is the mold release called PVA. This pic was before I rinsed it off. You can see the aluminum strips I added to either side of the seam. Those will be coming out. More trouble than they are worth. I was expecting it to be more difficult than it was to laminate inside, once the halves were together, but it wasn't a biggie.

When I made this mold, I hadn't used this epoxy resin before. I made a couple small parts to see how it acted. Glad I did. I learned that it's got a much longer drying time than polyester resin, and it doesn't chemically bond in the same way by softening the under layer, so it's much more likely to pull up in a tight radiused corner than polyester, known as bridging. The upside is you can laminate all your layers at once, unlike polyester, because there's no heat created that can wreak havoc on the lamination. You can laminate more in one go, but it takes way longer to dry, so it's a give and take. The best part about this epoxy is there's virtually no fumes! Polyester resin is gnarly. It stinks up the outside.

After those couple little projects to get a feel for the epoxy resin, I had to go back into the mold and add that black tinted resin and cab-o-sil to the inside corners to build up the radius to avoid bridging, then had to sand them all smooth. More tail chasing, but the result was good, faster and less work than a new mold.

Here's all the fittings bonded in. I think I might lay in a couple more layers after @Triton Thrasher reminded me how burly those Unity tanks were/are. A bit more work to seal those holes is worth the weight. After the extra layers, I'll lay a fillet of JB Weld around the threaded bosses to make sure they're sealed, particularly the ones below the oil line.

I decided to put the return line at the back corner. I've got an oil filter that sits below the tank, and the routing is pretty onerous. Going to the back cleans up that tight area and allows much more linear room to get the same job done. Also, one less hole below the oil line. I'm putting the return flow restrictor into the hose splitter to the rockers that will sit right below the elbow into the tank. I'm using a run-of-the-mill 1/8" NPT hose fitting. It will be easy to change hose size should the motor ever change.

View attachment 113171

View attachment 113172

No one has piped up about the potential drain plug on the bottom. What do you reckon? Worth the risk? Not sure how I'd do it. It would need to have a permanently mounted hose as to not spew oil over everything below when draining. And with the hose in place, where/how would you add the plug/tap? A ball valve seems way overkill. Maybe just a hose fitting with a bolt into the end? Hmmm...
Click to expand...
How about using an electric oil drain pump? They seem to be commonly available now.
 
Got a couple steps further on the tank.

Viewer Discretion Advised. Or, A Fool and His Money Are Soon Parted.


Built up a bit more of a flange around the return boss. I'll have to make a change to that portion of the mold for next time, so it's all done at once, rather than left to this point. With the additional flange, there's more overlap in the laminate, so less of a chance to leak.

Viewer Discretion Advised. Or, A Fool and His Money Are Soon Parted.


Gooped on a fillet of JB Weld around each of the blind bosses to make sure they're sealed. You have to cut a hole through the fabric to get the boss through, so there's a chance a pinhole might go all the way through. Probably not, but it sure would be a bummer if one of them leaked and I had to open it up again.

Viewer Discretion Advised. Or, A Fool and His Money Are Soon Parted.


All sealed up. Hopefully for good.

Taped it shut, and a healthy amount of cab-o-sil pushed into what minimal gap there was between the clamshell and the back/bottom panel, and laminated a layer of fabric tape over what wasn't blue taped. Once this dries, I'll peel the painter's tape and do the same to those spots and laminate 3-4 more layers of fabric over the back/bottom panel and a few additional over the corners. I made the the plug so it would have a pretty large radius on the back and bottom panel, so the final layers could be sanded down and the final radius would work out to about what the rest of the tank has. We'll see how well that plan works out. I'm about 50/50 for foresight on this project.

All the bosses are just below the surface of the fiberglass, so everything but the spigots for the feed filter and Monza cap can be removed and the surfaces can be block sanded more easily for nice flat faces.

Actually starting to look like a tank!
 
t ingermanson said:
Got a couple steps further on the tank.

View attachment 113291

Built up a bit more of a flange around the return boss. I'll have to make a change to that portion of the mold for next time, so it's all done at once, rather than left to this point. With the additional flange, there's more overlap in the laminate, so less of a chance to leak.

View attachment 113292

Gooped on a fillet of JB Weld around each of the blind bosses to make sure they're sealed. You have to cut a hole through the fabric to get the boss through, so there's a chance a pinhole might go all the way through. Probably not, but it sure would be a bummer if one of them leaked and I had to open it up again.

View attachment 113293

All sealed up. Hopefully for good.

Taped it shut, and a healthy amount of cab-o-sil pushed into what minimal gap there was between the clamshell and the back/bottom panel, and laminated a layer of fabric tape over what wasn't blue taped. Once this dries, I'll peel the painter's tape and do the same to those spots and laminate 3-4 more layers of fabric over the back/bottom panel and a few additional over the corners. I made the the plug so it would have a pretty large radius on the back and bottom panel, so the final layers could be sanded down and the final radius would work out to about what the rest of the tank has. We'll see how well that plan works out. I'm about 50/50 for foresight on this project.

All the bosses are just below the surface of the fiberglass, so everything but the spigots for the feed filter and Monza cap can be removed and the surfaces can be block sanded more easily for nice flat faces.

Actually starting to look like a tank!
Click to expand...
I'm really interested in this
I've never worked a bit of glass fibre in my life
I'm pretty sure if attempted this I'd have a bit of glass fibre oil tank glued to my hand for the rest of my days!
 
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