How To: Secondary Stand Alone Fuse Block Install

This will be my first “How To” contribution for Tacoma World, so hopefully it will come to good use or possibly give people other ideas. If anyone wants dimensions I can try and take rough measurements to get you close.

GOAL: Have a secondary fuse-able power source for accessories and other devices without tapping into factory wiring. Also building a tray to hold these components.

SOLUTION = below...

PARTS:
1 - 16”x8” Sheet of Lexan
1 - Scrap Piece of 1/8” Aluminum
1 - Blue Sea Systems ST Blade Fuse Block [PN# 5025 - 6 Circuit]
1 - Blue Sea Systems 187 Series Thermal Circuit Breaker [PN# 7144 - 100A]
AWG 4 Wire
6 - AWG 4 Ring Terminals for 1/4” Stud Size
1 - Bolt that holds on the rear bracket for the engine cover
2 - 8mm-1.25x25mm Bolts
9 - 10-24x3/4” Machine Screws Pan Head
9 - 10-24 Nylon Lock Nuts
11 - No.10 Flat Washers
6 - 5/16” Flat Washers

TOOLS:
Heat Gun
Wire Crimpers
Sharpie
Utility Knife
Hacksaw
Dremel
File
Wrenches





FIRST:
-Figure out where you wish to locate the fuse block and breaker.
-Measure the dimensions of the space.

SECOND:
-If you really want to save yourself some money, time and effort... Mock up the tray using foam core board. I know it sounds a little tedious but it saves you in the long run.
-Make sure you do not cover something you may need to access certain things later on other the truck.
-More work, measuring and designing now means less work and headache later.



THIRD:
-After trimming and getting the foam core mock up as close to the design you want it, flatten the design and transfer the mock up to the Lexan. Mark any areas that need to be completely removed, and mark where the bends need to go.
-Using the utility knife, hacksaw or Dremel; cut off all the large chunks that are not part of the design.

*Notes*
-It is easier to cut as much of the Lexan as you can while the piece is flat because once you bend it, any small mistake and lead to further problems.
-Use the hacksaw to cut the shorter straight edges. The Dremel causes the Lexan to MELT!!!
-Use a utility knife on the longer straight edges, and break the Lexan like you would score a piece of glass and bend to break off the chunk.



FOURTH:
-After removing the large chunks of unnecessary Lexan, you are ready to bend the piece.
-This is the tricky part. You don’t want to get the Lexan too hot or it will bubble, too cold and it won’t bend. Between 20 and 30 seconds on high heat should do the trick. Making sure to move the heat gun back and forth.
-Once bent, trim off any corners or any excess you do not need to slim the tray down.
-File the edges to de-bur them.

*Notes*
-Test on some scrap pieces of Lexan
-Tiny bubbles are okay.
-Anything that is touching the Lexan will melt to it or transfer the color / pattern to the clear Lexan.
-I chose to sand the Lexan with 1500 grit to make mine cloudy so scratches don't show up easily. You could paint it if you like.





FIFTH:
-Once you have the Lexan tray looking and fitting how you want it to, you need to fabricate a bracket to support the end of it.
-Using the scrap aluminum, fabricate a support bracket that will allow you to bolt it to the free spot on the inner wheel well and the edge of the Lexan tray.



SIXTH:
Bolt all the pieces up, bolt the tray and bracket into the truck.





SEVENTH:
- Run the wire.

 

*The circuit breaker is to protect all the accessories wired to the fuse block, also to protect the truck. Don't want too much current draw to start melting things. My father is an electrician so the safety and protection things are inherited.

*Fuse Block and Circuit Breaker are Marine grade components. Weatherproof to weather resistant.

*100A Circuit Breaker performs three tasks. It serves as an on/off switch, 100A Fuse, and circuit protection trips if draw exceeds 100 amps.

*AWG 4 Wire will handle up to ~ 135A. That is the reason I went with it. Remember the shortest route means less resistance and better current flow. If you are drawing the upper limits of the amps, unnecessary bends and excess length are not a good thing.

*I used all stainless steal hardware for rust prevention and longevity.

*Lexan was chosen not only for its inherent strength / durability and weight, but I don't want the chance of any arc or shorting to ground on any of the connections or wires.

 

Very nicely done i am going to be doing this here i have a buddy that wants to do it, and i may be adding a secondary battery. Thanks!!

 

I like it. I need to get this.

 

Nice job man! I never thought about using plexi...Looks pretty similar to mine.

 

Yep pretty similar. I wanted something light and durable. One thing I would note is the reason I used the breaker I did, was because it was weatherproof and combined all the things a couple of your components are accomplishing. I am NOT knocking your design by any means. Just simplifying and compacting. Granted the breaker alone cost me $85.

Ilovetacos - is that in line fuse for your amp / speaker system or is it protecting the fuse block?

*I wouldn't use plexi though, Lexan has a different density. I wouldn't know how plexi would react to the heat gun. I am not saying it can't be done, I just know the stress tests put on Lexan are different.

*There are three types of products out there that people need to be made aware of. Acrylic, Plexi-Glass and Lexan. All behave differently and are made of different compounds.

 

good post... ill be doing something similar soon

 

Nicely Done.

 

Looks like the most common place to mount these guys

 

The amp meter you are seeing in mine is connected to my amplifier. The breaker is the only fused component connected to the fuse block.

Why was your breaker $85?

 

Great job w/ the lexan!

 

Marine grade component manufactured by the same company that produced the fuse block. Weatherproof and sometimes touted as waterproof, it's nice and beefy though.

I think it may be because of the name stamped on it. Honestly it was easier to go with the same company just for making my life easier. I live along the coast so we have a bunch of boat shops and parts stores that carry their stuff.

 

Nice man! Again the install looks good!

My breaker was a $15 cheapy off of eBay.

 

Thanks man. I just hope I left enough room for supercharger components.

Anyone know where or how they relocated the Hood Sensor for the alarm? Going to have to do that for when I install the hood struts.

 

Nice job!

What's the thickness of the Lexan? Appears to be 1/16 inch when compared with the aluminum...

I've a similar set up but use Blue Sea 7102 for the breaker; interrupt rating 3000A@12V w/push button reset instead of 5000A w/lever reset in the 7144, but about half the price, and no problems in 14,000 miles since installing.

 

looks good. But won't everything running off that block be hot all the time, even when the truck is turned off?

 

Yes, running strait from the battery will be hot all the time (this is how I did my aux fuse block, as I wanted to be able to run comms without having truck on).

You could easily throw a 100A mag relay in the mix and trigger it off of your ignition or any switch power to make the whole block switched though, if that’s what you want.

Unfortunately there is no switched power (even the strait ignition wires) that are 100A rated, so you must run a relay.

 

The Lexan is between 1/16" and 1/8". At Home Depot they only had one thinckness, but all different size sheets.

 

What barlows said...

HAM radio, Front and Rear Lightforce Lights, etc. Wanted the ability to run devices without truck being on. I will throw switches in the cab when I run the cables.

You can easily do what barlows talked about, running a relay that clicks with the ignition. You can wire it up how ever you wish.

But my other main concern is when I get any service done on it, I can flip the breaker switch and those devices won't work, and therefore the service techs can't leave crap on.

 

Following Ilovetacos direction (using plexi though):