My new chassis - documented with pics

[jgunn]

The last thread I started, about PVC hilts and decorative fluting, got some nice responses, so when I decided to gut the saber and rebuild the insides to be more neat and durable, I decided to document it as well.

I've seen plenty of posts showing sleds/chassis but I hadn't seen a step-by-step so maybe this will be helpful to someone. This was all done with simple tools; a drill, a bench grinder (you could use a file if you don't have a grinder and you're patient), a hacksaw, a sharpie, needle-nose pliers.

I started by finding some fender washers that were the same diameter or bigger then the inside diameter of the 1 1/4" PVC tubing that I used for the grip section of my hilt. Here's a pic of the washers I found, some 6-32 threaded rod bits, and a piece of PVC I'm using to check the fit.

http://farm5.static.flickr.com/4092/5216482624_c88b471f60.jpg

The washers are just a bit too big - this is good because I want them very snug. So, off to the bench grinder. I'm rotating them slowly as I grind to take off material evenly. Goggles, mask, and cut-resistant gloves here, folks... work safe.

http://farm5.static.flickr.com/4086/5215894645_2ea54de1e5.jpg

Once the washers just slide into the PVC, its time to drill some holes for the chassis rails. I place nuts on the washer and locate them (I did it by eye) where I want the rails to be. Note that the nuts are positioned so that they don't overhang the washers - this is important so they don't stick out and drag against the inside of the PVC. I marked where the holes will be with a sharpie. Stack the washers, drill the holes - this will give you matching holes on both washers.

http://farm5.static.flickr.com/4110/5215894745_84739d3ab4.jpg

Use drill bits intended for metal here. If you try to use the ones you had kicking around for making holes in drywall for hanging picture frames or whatever, you'll be at it all day. A drop of oil on the tip of the bit helps too.

Once you have your holes, you can put the chassis together - on each rail you have a nut, the washer, another nut, and then repeat on the other end. Some thread locker (loctite, whatever) will keep the nuts in place.

http://farm5.static.flickr.com/4083/5215894825_dc18190c95.jpg

Some heat-shrink on the threaded tubing might be good for avoiding shorts, but I don't plan to have exposed circuits so I'm not worried.

So that's all great, but then I figured out that there wasn't enough inside space to cram three single AA holders. I know I was being ambitious, but... well, anyway, I decided to make another chassis using the same steps, but long enough to hold a 4xAA battery box. No biggie, I cut longer pieces of 6-32 threaded rod. They are the length of the battery box, plus two times the stack height of the end hardware. Each combo of nut-washer-nut is 1/4", so the rods are the length of the box plus 1/2".

http://farm5.static.flickr.com/4087/5215894905_9a08128416.jpg

Now its time for some cram-fu. The tolerances for the battery box in the chassis with any sort of holding apparatus (I'm thinking zip-ties) are very tight. Thankfully the inside nuts for the rails grip the box quite snugly, I almost don't need the zip-ties. Here's a shot of the box zip-tied to the rails.

http://farm6.static.flickr.com/5203/5215894979_bc88bfe46f.jpg

And once I get it attached on all 4 corners, I pop the batteries in and test the fit. I've made the mistake before of only doing test-fitting with the holder, not with batteries, and that caused problems since the batteries can extend past the corners of the box. Looks good:

http://farm5.static.flickr.com/4125/5216482190_08da018a2e.jpg

I've wired up an econo-board with a tip42 transistor and a micro-puck driven Cree LED. Using tight runs of wire, I zip-tie the board to the rails on the back of the battery box. The wave sensor is hot-glued. I made a notch in the washer to pass wires through, for the switch, LED, and speaker. The magnet for the crappy speaker that came in the Hasbro saber nestled nicely in the inside washer opening, so I hot-glued it there.

http://farm5.static.flickr.com/4107/5216482336_53e16b1395.jpg

http://farm6.static.flickr.com/5249/5216482422_34f370650a.jpg

I put a D-ring on the pommel end of the chassis to help pull it out since the fit is so snug.

http://farm5.static.flickr.com/4132/5215894469_a90c33e3ac.jpg

That's about it - now the saber guts, aside from the switch and LED, are contained in one unit that is easy to slide in and out for battery changes or repair.

Fun stuff.

[Lord Maul]

Nice job! Isn't it a great feeling when everything fits *just* perfect? Your wiring is nice and clean too. No spaghetti at all. I have to remember the zip-tie trick, I usually just superglue my batteries in place

[RevengeoftheSeth]

Great tut, brudda! Thanks for the quick down and dirty!

[Knighthammer]

Very impressive.

[equinox13]

very very well done! thanks for the great documentation. i know i'll be stealing an idea or two later. ^_^

[DarthPawley]

A great job and a really well presented tutorial.
Well done!

[jgunn]

@equinox: steal away, that's the idea... everyone contributes, and we move the art forward. ;)

@everyone else - thanks for the supportive comments!

A few things I thought of after I posted...

1) in some of the pics, you can see one of the AA batteries looks like its made from wood (like the 3rd to last pic). That was a dummy battery I made from a wooden dowel with a drywall screw through the middle. I only wanted 4.5v out of the pack but the 2x2 arrangement of batteries made sense for my layout, so that was the easy compromise.

2) You can see in the last pic that the nut holding the D-ring on is barely gripping, that's because I didn't think to add it till long after I had cut the threaded rod. I may replace just that one rod which won't be hard since that rail runs over the battery box and nothing is attached to it.

3) I'll add some pics of the chassis in an actual saber soon, I realized after the fact that my shot showing the final fit at the end looks a bit like my saber is a used sewer pipe. :/

Aaaaaanyway, carry on.

-J

[dgdve]

That is nearly exactly what I do for my chambers, I really like to use a 4 post system and switch to 3 posts at the battery compartment.. another thing to note is that you can cover the 6-32 coarse threaded (all thread) with brass 3/16 o.d x0.014 tubing... makes it have that real finished look and then your chassis is "display ready" also I use 1.25 nylon washers instead of flats because they have different thickness's and you can fill spaces by using the really thick ones (I mean thick they make them up to 1/4"..thats thick) or thin ones if you need them to be slim, then you can paint them if you like. ONLY thing is dont over tighten the nylon washers as they will warp and misalign IF your using thin ones.. aside from that your tut is A++

[RevengeoftheSeth]

1) in some of the pics, you can see one of the AA batteries looks like its made from wood (like the 3rd to last pic). That was a dummy battery I made from a wooden dowel with a drywall screw through the middle. I only wanted 4.5v out of the pack but the 2x2 arrangement of batteries made sense for my layout, so that was the easy compromise.



I do the same thing for dummy batteries! Dowel rod with two flat metal thumb tacks.

[dgdve]

I'm sry but I keep saying to myself... is that a chassis.. in a Pvc...
(I need to see the emperor immediatly...) the force is strong in this one... great great job, I'm watching you

[jgunn]

LOL. I'd better hide out in a swamp on a remote moon so I can practice my sabersmithing skills out of the reach of the Emperor.

[jedimastergarcia87]

I love your new chassis. I was wanting to build one just like that but to hold just a sngle crystal for an MHS saber. How can I go about doing that? Thanks.

[jgunn]

Well, that's a pretty open-ended question... my post was intended to give people steps to build a basic chassis that you could turn into whatever you wanted; in my case, I sized it for a 4xAA battery box and some electronics. You could to the same to suit whatever you need to hold.

I could try to be more specific if you could provide a sketch or some sort of design, maybe. If I were just going to do a crystal chamber only, I would build my chassis about the same as the one above, but long enough to hold my crystal plus the hardware to hold the crystal in place.

I would try to find some fender washers of the right diameter for the MHS parts (I haven't used any MHS so I don't know the inside diameter offhand) but that didn't have as big of a hole in the middle since that's where you will want to put your crystal supports. The big holes worked out well for me in case I wanted to do routing of wires through there.

You could use some knurled brass nuts for the crystal supports(Home Depot, miscellaneous hardware, and sometimes in the lamp department) like these:

http://www.amazon.com/8-32-Knurled-Nut-15-pieces/dp/B003QZP7Y0

I'd just hot-glue a superbright LED on the bottom of the nut under the crystal and it should light up nice and bright. :)

-Jgunn

[Knighthammer]

I've wired up an econo-board with a tip42 transistor and a micro-puck driven Cree LED.

so how did you wire that one up - I would assume tip42 to positive of the micro-puck. Better then going with a resistor? aren't most of the micropucks LOW amperage? To low for 3w LEDs?

[Crystal Chambers]

Nice and clean package there...zip ties are great! I have seen them used before but a great idea and reminder.

Instead of a battery dummy you can also solder a wire across and use the space for a li-ion PCB or power extender.

[jgunn]

so how did you wire that one up - I would assume tip42 to positive of the micro-puck. Better then going with a resistor? aren't most of the micropucks LOW amperage? To low for 3w LEDs?

When I originally started making the PVC sabers, I was following the lead of Jay-Gon; his original article about PVC sabers described using the micro-puck so he could get away with 2 AA or AAA batteries. That's how I started, too. When I decided to add the sound boards, I wanted to preserve the puck because they are usually more efficient than straight resistors. So I followed the general tip42 wiring diagram posted elsewhere on this site, but the switched load on the transistor is a 4.5v connection to the battery back driving the micro-puck, driving the LED. I think micropucks max out at 500ma, so probably too low for most people. In theory you could do the same with a basic puck, the theory is the same - econo board driving a transistor to switch a higher-power circuit for the LED.

(I'm driving mine a little hard at 4.5v, not recommended but seems fine)

Hope that helps,
J