RAMBo Fuse Hack

[addisonElliott]

Hello,
So I just recently finished building my printer and while I was calibrating the fan wires up top shorted out and blew my F3 fuse. This is the small surface mount one that power the whole board, so now my printer wont turn on.

I ordered 10 peices from eBay, however it is going to take 10 or so days to get here because they are coming from China. They were pretty cheap.

Until then, I do not want to sit around with a dead printer, so here is a little guide to hack a fuse that will fit into the compartment.

What you will need:
Broken fuse from the holder
5A or 10A Fuse. This can be glass tube or the automotive blade type. 10A is a bit higher than what it should have, but I don't believe they make 5A automotive fuses. This can be bought at a hardware store.
A fuse holder that fits your fuse you bought. This can be bought at a hardware store as well.
Soldering equipment

Note: In my case, I did not have a fuse holder handy, so I soldered wires directly to my fuse.

Take your fuse holder and strip about 1/4" of wire off of each end.

Then bend the wire at a 90degree turn.

Wiring bent at 90 degree angle

Go ahead and heat up your soldering iron. Once it is heated up, tin the ends of the fuse holder. For those of your who don't know what that means, it means put a thin layer of solder over each end.

Wiring tinned

The broken fuse has text on one side of it. This is the top, so orient the fuse so that the top is facing up. With this orientation, you want to put the fuse in a vise so that it is aligned with the top of the vise. This prevents solder from getting on the sides of the fuse and preventing it from plugging in again.

Broken fuse placed in the vise

Once it is in the vise, take your soldering iron and put a bit of solder on there. You want a little bit of a glob. With one hand grab a wire from the fuse holder and place it directly on top of the metal portion of the fuse(left or right side, it doesnt matter). With the other hand, grab your soldering iron and press it on the wire(with the glob of solder on the iron touching the wire). It should very quickly melt the solder and flow to the fuse. Do a stress test to make sure it is pretty strong and that it is not a cold solder joint.

Wiring soldered to the broken fuse.

Repeat for the other wire.

Quick Test: Plug in a fuse to the fuse holder, turn your multimeter to ohms and press the leads directly against the broken fuse. It should read close to 0 ohms now. This means everything is soldered correctly.

If you took the fuse out of the vise, go ahead and put it back in. Now layer some liquid tape over the metal so that it does not short against anything. Try not to get any on the sides or on the body of the broken fuse because it will not fit back into the holder.

Now plug in the broken fuse and get the wiring out of the way. You're done.

Finished product! Right above the LCD adapter is where I have the fuse plugged in.

This is meant to be a temporary fix. If you are wanting to use this long term, then you might as well solder a fuse holder directly onto metal prongs on the RAMBo and use that. The purpose of soldering to the broken fuse is so that you can place a new fuse in once you get some.

[McSlappy]

Here's one I prepared earlier.

[img]http://i.imgur.com/Kvt5Pfr.png[/img]

Same situation as you - didn't want to wait a couple of weeks to play!

[Eaglezsoar]

Good ideas from the both of you. Saves you being down while the fuses are being sent.
When I had to order them, I ordered (10) of the 5Amp nano fuses and (10) of 10Amp nano fuses.

[miglo]

Wish I saw this post earlier. My 10 pack from digi-key finally came today

[joseph]

Or you can buy the fuse at Mouser (http://www.mouser.com" onclick="window.open(this.href);return false;), part # 576-0448005.MR. Takes a few days depending on shipping.

[addisonElliott]

Or you can buy the fuse at Mouser (http://www.mouser.com" onclick="window.open(this.href);return false;), part # 576-0448005.MR. Takes a few days depending on shipping.

Say I buy a 10-pack from mouser, that's $0.928 * 10 = $9.28. But there is an additional $7.99 in shipping which puts it up to $17.27 at the minimum. Yes if I were to buy many other things then this isn't that bad of a deal, but the fact is I rarely buy from mouser because of the cost always being more than if I were to buy it on eBay.

I bought a 10pack of these fuses for $4.99, with free shipping on eBay. It took about a week to receive them.

I'd say that waiting a bit longer for it is worth $12 for me. Also, 1-2days can still be a long time for someone who wants to print now.