Should I run away from these fuses?

Discussion in 'Amp Central Station' started by Milspec, Feb 22, 2020.

  1. Milspec

    Milspec Friend of Leo's Silver Supporter

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    fuses 040.jpg fuses 039.jpg

    I needed some 4 amp fuses for my '79 Twin this past week and nobody local carried them. I went everywhere from the hardware stores, home improvement centers, and even a place that restored old arcade games, but all that I could find were 1,2,3, and 5 amp slo-blo / delay fuses. I even had one shop tell me that there was no such animal as a 4 amp...clearly wrong.

    Anyway, so I had to go online and found several retailers offerring slo-blo fuses in all amp ratings. Ended up with a deal for a large box containing a dozen containers of 4 amp, 250v, 1-1/4, 1/4 slo-blo fuses. All seemed well and I was set for life.

    The problem is the fuse appears different than any delay fuses that I have used before. The end caps do say 4 amp, 250v, slo-blo, but the inner coil looks quite a bit...well, cheap and dangerous.

    Instead of the coiled wired all the way from cap to cap, there is a blob of solder halfway between the caps. I am no electronics guru, but that doesn't look like that would be all that accurrate nor safe to use. Would it actually fail at the right rating or not...seems like solder would be unpredictable.


    Are these actually some fake tubes made off-shore or are the just another design? More importantly, are they safe to use to protect my transformer?
     
  2. trxx

    trxx Tele-Holic

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    Pretty sure my mid 70's twin has the same style fuse, transitioning from a coil to a straight wire around halfway through.
     
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  3. Andy B

    Andy B Friend of Leo's Silver Supporter

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    I’ve got boxes of fuses from my Father’s stash that look just like that. They are fone to use. The internal construction determines how slow they are to open.
     
  4. Guitarteach

    Guitarteach Poster Extraordinaire

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    I have a few like that in my Boogie maintenance stash.
     
  5. Milspec

    Milspec Friend of Leo's Silver Supporter

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    Sounds like I might be okay then...was pretty worried about it. The last thing I want to do is damage something by cheaping out on the fuse.
     
  6. muchxs

    muchxs Doctor of Teleocity

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    Speaking of milspec… crack open just about any tube military communications gear built since WWII, those are the fuses you'll see. Either Buss or Littelfuse.

    Probably the same fuses that put a man on the moon.
     
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  7. Milspec

    Milspec Friend of Leo's Silver Supporter

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    The brand or this design? You know about this stuff far more than I, but this is the first time I have seen a slo-blo without the continuous coiled filament.
     
  8. muchxs

    muchxs Doctor of Teleocity

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    Both.
     
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  9. Gunny

    Gunny Tele-Holic

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    I've handled countless sizes and amperages of slo-blow fuses in my working life. 30 yrs in nuclear plant maintenance and my lengthy hobby of amp modifying, building and repairing. There's nothing to worry about with the fuse you have shown us here.
     
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  10. Milspec

    Milspec Friend of Leo's Silver Supporter

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    Thank you sir, I worked in the nuclear world for 12 years myself and now how picky the standards are so if you feel confident, so do I.
     
  11. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    No, I would run from this fuse ............trust me on this one


    Smoke_bomb_with_burning_fuse.jpg
     
  12. vanr

    vanr Tele-Afflicted

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    I recently had to hunt down some 2 Amp Slo Blo fuses. The new ones looked much different than the one that blew (which was probably 20 years old). I chalked this up to newer manufacturing techniques. They work fine.
     
  13. corliss1

    corliss1 Friend of Leo's Platinum Supporter

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    Looks like a fuse to me.
     
  14. LightningPhil

    LightningPhil Tele-Meister

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    To put it in Yogi speak:

    If it looks like a fuse, tastes like a fuse and kabooms like a fuse, then it must be a fuse.

    They won’t become more conductive with age. Go ahead and use them. If they kaboom a bit too often, wrap a bit of foil around it before inserting. No, wait, don’t do that last bit.
     
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