I have several aluminium chassis top plates for amplifier projects where I've drilled holes in the wrong place and want to fill them up to give an aluminium finish and disguise the hole. Ideally I just want a tube of something that looks kind of silver so I don't have the bother of mixing epoxy. These are just 3mm or 4mm holes. No strength required. Like equivalent of plastic wood, but with a metal finish.
So what cheap and easy products can I use? I'm in UK so should be available here - e.g. well-known brands should be widely available.
I found some CTI sealant in a silver colour - something like that?
https://www.ebay.co.uk/itm/29511895...KPoBJ9kIizYOQpCtGrZtv2RViW5R|tkp:BFBMyoCi6-Ng
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So what cheap and easy products can I use? I'm in UK so should be available here - e.g. well-known brands should be widely available.
I found some CTI sealant in a silver colour - something like that?
https://www.ebay.co.uk/itm/29511895...KPoBJ9kIizYOQpCtGrZtv2RViW5R|tkp:BFBMyoCi6-Ng
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Maybe use the Harbor Freight aluminum brazing rods to fill the holes and then plane it down - will involve using a torch, though. Something similar should be available in the UK.
I understand your problem -I have been there, more or less-, but I don't think you will find an exact matching product for the base aluminum.
There are aluminum-filled resins around, but they cannot match the true, solid model.
You could try to make your own filler for that purpose by mixing an excessive amount of aluminum powder with a binder, epoxy, acrylic or polyester, but the mechanical integrity will be compromised (not a problem for you, normally), the look will not be right (it will have a "sandy" look), and aluminum powder can react violently with some oxidisers, like resin catalysts.
IMHO, the best you can achieve is to fill the holes with the best compound you can find or brew yourself, and disguise the end result with a finish including sanding, covering with a light disguise like diluted paint.
Arranging the layout can also help: if you manage to hide the offending holes beneath the wide skirt of of a control knob, it could help a lot
There are aluminum-filled resins around, but they cannot match the true, solid model.
You could try to make your own filler for that purpose by mixing an excessive amount of aluminum powder with a binder, epoxy, acrylic or polyester, but the mechanical integrity will be compromised (not a problem for you, normally), the look will not be right (it will have a "sandy" look), and aluminum powder can react violently with some oxidisers, like resin catalysts.
IMHO, the best you can achieve is to fill the holes with the best compound you can find or brew yourself, and disguise the end result with a finish including sanding, covering with a light disguise like diluted paint.
Arranging the layout can also help: if you manage to hide the offending holes beneath the wide skirt of of a control knob, it could help a lot
Perhaps this? https://www.ebay.co.uk/itm/22347756...7779&msclkid=4d7b2fe9ce811a03d9214cf39e94c7fa
Haven't tried it so, as Elvee says, can't comment on the set colour.
Haven't tried it so, as Elvee says, can't comment on the set colour.
It's sort of an "art" to design something original, and as Andy is in such a field, careful pre-planning is the key to perfection.
This requires making templates, careful measuring, taking into account components, etc, not a huge undertaking.
However some bypass these procedures as being too tedious and time-consuming.
Thus... mistakes happen.
If I slopped up a chassis, and insist on perfection and appearance, I'd simply get another one and start again.
And I am a perfectionist in that way.
This requires making templates, careful measuring, taking into account components, etc, not a huge undertaking.
However some bypass these procedures as being too tedious and time-consuming.
Thus... mistakes happen.
If I slopped up a chassis, and insist on perfection and appearance, I'd simply get another one and start again.
And I am a perfectionist in that way.
That looks promising. I thought I'd fill the holes and then brush the aluminium. Since they're small holes they shouldn't be too obvious. Better than leaving holes anyway.
Completely agree about cleverly putting stuff on top of holes - capacitor holders and heat sinks are the most obvious. You can also get grey plastic circular inserts for various size holes.
I'm talking about experimental chassis that get used a few times. I have so much of this stuff, it's valuable just in terms of the aluminium in it. Not something I want to bin if I can save it!
If you are going to paint the surface use JB Weld two part epoxy. It is stronger than the aluminum! You can tape a small piece of wax paper below the hole and place it on a flat surface to act as a dam to hold the epoxy as it cures in a few hours. Cleanly smooth the patch and try not to have a lot of overlap. It dries harder than steel! Sand it flush and remove the wax paper from underneath and paint it. It will be there forever, maybe longer. You can saw, drill, sand, and paint the stuff.
I thought about that, but I want something silver close to aluminium in colour. I'm not going to paint it.
why not make even more holes and disguise them as cooling perforation?
ok, maybe that was not entirely serious ... 😉
ok, maybe that was not entirely serious ... 😉
Or just install a bolt in there that does nothing. Zero work.
You were gonna put a bolt there anyway, so what's the big deal?
You were gonna put a bolt there anyway, so what's the big deal?
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In a tweak on this approach, countersink the holes and use flat head screws. Very small amount of work.
Yes, if it's under a part that would conflict with the screw head. Otherwise, still too much work.
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How about running a screw through the back and cutting off what is sticking out on the side you want to polish up.
OR
Tap all the holes to the same size, deburr the holes on the side facing out. Use long screws and red Loctite or JB weld.
Run your screws, studs, or whatever you use and let them dry at least 24 hours.
Tape off the studs on both sides around the holes. Cut the screws flush on both sided with a fine Dremel cutoff wheel.
Remove the tape and polish the plugged holes via polishing wheels and jewelers polishing compounds.
OR
The whole piece with rubbing compound.
You'll be hard pressed to see anything.
Cost? A hand full of screws for 2-5 euro. Loctite? Superglue? Cutoff wheels?
You should see me work on my own teeth or tooth I should say. I fumbled it 31 times before I got it right.
Practice makes perfect.
Regards
OR
Tap all the holes to the same size, deburr the holes on the side facing out. Use long screws and red Loctite or JB weld.
Run your screws, studs, or whatever you use and let them dry at least 24 hours.
Tape off the studs on both sides around the holes. Cut the screws flush on both sided with a fine Dremel cutoff wheel.
Remove the tape and polish the plugged holes via polishing wheels and jewelers polishing compounds.
OR
The whole piece with rubbing compound.
You'll be hard pressed to see anything.
Cost? A hand full of screws for 2-5 euro. Loctite? Superglue? Cutoff wheels?
You should see me work on my own teeth or tooth I should say. I fumbled it 31 times before I got it right.
Practice makes perfect.
Regards
Another alternative would be just to park a screw of appropriate diameter in the hole with a nut on the other side. No one needs to know that the screw is just an "oops" rather than for some legitimate purpose.
I just get my buddy to weld the hole closed and sand it out. It worked just fine.
I have also filled with epoxy, sanded and painted to holes.
I go for the no holes look in my projects and fill all the holes with epoxy even with stainless screws in them from the other side.
Make sure you clean the hole with a strong solvent cleaner like laquour thinner before you use any thing other than aluminum welding.
I hope this helps
I have also filled with epoxy, sanded and painted to holes.
I go for the no holes look in my projects and fill all the holes with epoxy even with stainless screws in them from the other side.
Make sure you clean the hole with a strong solvent cleaner like laquour thinner before you use any thing other than aluminum welding.
I hope this helps
Use rivets, or filled epoxy, we have a local brand called Metaset, with iron powder or aluminum powder filling.
Used a lot to repair castings, strong enough to be machined, and tapped.
JB Weld sounds similar.
There are companies like Belzona who make ceramic filled epoxy compounds as well, interesting stuff.
Personally, I would countersink, and use rivets, those are easy to obtain here, and leave the heads alone, if really needed.
It is sweating hot here at 8 am today, need ventilation, so why not let the air circulate?
Used a lot to repair castings, strong enough to be machined, and tapped.
JB Weld sounds similar.
There are companies like Belzona who make ceramic filled epoxy compounds as well, interesting stuff.
Personally, I would countersink, and use rivets, those are easy to obtain here, and leave the heads alone, if really needed.
It is sweating hot here at 8 am today, need ventilation, so why not let the air circulate?