Hi everyone, I'm looking to replace and upgrade some rubber (or foam?) under toroidal transformers in some amps. It's not something I've done before, and I'm struggling to know what the best stuff is to get and where to get it from (in the UK). Any pointers?
I'd like to buy decent-quality stuff, but the likes of sorbothane is far too expensive. 2mm would be ideal.
Thanks.
I'd like to buy decent-quality stuff, but the likes of sorbothane is far too expensive. 2mm would be ideal.
Thanks.
RS and farnell have these , in various diameters, specifically for the job.
If you want thicker, it's ok to double up, on both sides
I'll find you a link to start you off
Mounting Kits | RS Components
Please, please when you tighten up, just tighten it just enough to stop the TX moving, I usually try turning as I tighten to see if it's just right, as soon as I can't rotate it , it's the right tightness.
If you want thicker, it's ok to double up, on both sides
I'll find you a link to start you off
Mounting Kits | RS Components
Please, please when you tighten up, just tighten it just enough to stop the TX moving, I usually try turning as I tighten to see if it's just right, as soon as I can't rotate it , it's the right tightness.
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If you need something THICK for a 20 or 30 pound toroid, use acoustic damping foam. Has a little more give than mouse pad rubber (which is what you want if it’s heavy), but 1/4” or more thick so it can handle a little bit of tightening and a few G’s of shock. Usually used in car audio installs, so it can handle the heat.
Why not get sheet and cut it to size?
Solid Neoprene Rubber Gasket Sheet 130mm x 130mm x 3mm thick | eBay
Solid Neoprene Rubber Gasket Sheet 130mm x 130mm x 3mm thick | eBay
Funny, I tighten mine with an impact driver. I can carry my tube amps by the transformers
I used to make it "snug" but I found they would be loose after 6 months of bass.
I'm cheap, so I would just cut a washer using the polythene lid for a coffee can. The material has enough give to make an effective washer between a toroidal transformer and chassis, and the price is definitely right. Tin snips to cut the outer radius, and a hollow punch to make the center hole.
That is one way.
I fear the semi elastic material used to seal coffee cans is too thin, and sometimes only glorified cardboard.
I would use that technique to cut actual rubber, say 3 to 5 mm thick.
In most medium-large cities you can find a "rubber shop" which among 1000 other things, sells ruber sheets,or Hobby/Crafts shops which sell sheets of spongy but firm EVA rubber for peanuts.
Or maybe you (or your friendly mechanic) have around an old car rubber mat.
I've even seen draught sealing rubber and auto tyre tubes used for similar purposes. Tyres are tubeless now of course, but sometimes you find the odd useable "inner tube" at storage shed and garage clearances. The link is to just one possible UK supplier of materials for reference. There are dozens of them but you need to be aware that transformers can get hot in overload conditions and it's better to be safe than sorry with thermoplastic type rubbers which may melt at similar temperatures. Neoprene Rubber Sheet in Black | Provincial Rubber
Bosh. That's a toy. Here's a semi-pro typewriter. And it is on a "pad", but it appears to be cut from a door-mat. In the day they made rubber pads for the purpose.
Attachments
I think his question was ironic...
I have 2 electronic daisy wheel units too, Brother also.
All work.
That appears to be a really old Royal, some of them had the ribbon spools at the sides, later they went next to the type basket. The tab bar appeared later. Well preserved.
I have seen those thick pads, a substitute later was coir mattress foam.
Most typewriters have gone for scrap, I got mine for $4 at the flea market here.
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As for the transformer part, as JMF said, there are shops selling rubber items, sheets, belts, O Rings, coupling parts, and a myriad of seals and so on.
Just have them cut a piece, and make the ring.
And crafts / tailor material / shoe parts shops also would have high density EVA foam.
You can get gasket packing sheets too, even expanded Teflon sheets (expensive!)...
No need to approach a transformer maker.
Just have them cut a piece, and make the ring.
And crafts / tailor material / shoe parts shops also would have high density EVA foam.
You can get gasket packing sheets too, even expanded Teflon sheets (expensive!)...
No need to approach a transformer maker.
Probably.
That said, a disk, hand cut out of a generic rubber sheet will cost, say, $1 and be available on the same day.
A very similar original part, molded with manufacturer´s brand and/or some catalog number, shown in a service manual or parts catalog, inside its own transparent bag with Factory logo and ordered from Factory or Representative can cost .... what? .... 8 bucks? .... 16???? .... 32????? ..... whatever Manufacturer or reseller fancies that day.
Don´t start me on possible delays, or even manufacturer even answering mails for such a puny order.
Just thinking aloud, of course.
That said, a disk, hand cut out of a generic rubber sheet will cost, say, $1 and be available on the same day.
A very similar original part, molded with manufacturer´s brand and/or some catalog number, shown in a service manual or parts catalog, inside its own transparent bag with Factory logo and ordered from Factory or Representative can cost .... what? .... 8 bucks? .... 16???? .... 32????? ..... whatever Manufacturer or reseller fancies that day.
Don´t start me on possible delays, or even manufacturer even answering mails for such a puny order.
Just thinking aloud, of course.
Here the sheets are like rolls of fabric, different thicknesses, width, with or without a cloth layer, Neoprene, Natural, Viton.
Sold by weight (!).
So I can ask a 6in long strip from a 1 foot roll, and pay per kilo.
Then cut the ring myself, or ask a cobbler to do it...
Another issue is that many companies have gone out of business, more so during the pandemic.
Better to do as much as you can yourself.
Sold by weight (!).
So I can ask a 6in long strip from a 1 foot roll, and pay per kilo.
Then cut the ring myself, or ask a cobbler to do it...
Another issue is that many companies have gone out of business, more so during the pandemic.
Better to do as much as you can yourself.
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