My Senior design project - a "Swamp Thing" tracked vehicle clone

[The Fred]

Aircraft aluminum then insulate the inside. Better yet thin stainless welded to your frame, permanently, a metal skin would rigid up the cab and be safer.

Texture 111 and Elmer's glue? Just kidding but that's the road you are headed down.

You've come this far do the thing justice. Your workmanship is wonderful.

 

[aczlan]

Double-sided tape won't go it. Why not do something like pop-rivets?

They make tape that will work, IIRC, 3M calls it VHB tape. I would probably use pop rivets though.

Aaron Z

 

[Garauld]

3M VHB was the tape I was thinking of. I did plan to insulate the cab I probably would use pop rivets if I end up using abs. I welded in some X-braces yesterday onto the rear wall.

 

[ArlyA]

Having lots of experience with abs and hdpe, you need to compensate for the large differences of its expansion rates of those materials and steel, or whatever you attach it to. ABS and HPDE rates are high, that is they expand or contract much, with varying temps. I limited the size of each section while attaching it to steel to 2ft which may be a bit to large, plus drill very larger holes in the plastic, to allow its movement, etc, etc, etc. I've not used tape, but can not image how it could be used in these conditions.

 

[PILOON]

Not if I can help it. I plan to use glue or double-sided mounting tape for plastic siding and plug welds for metal.

May I suggest----

Urathane caulking, which has all the characteristics of automotive windshield adhesive.
And at a very affordable cost, comes in regular caulking gun tube size.

One brand I have used is Flextra.

I have 'glued' patches on tin roofs and it takes a pry bar to separate them.

Since plexiglass and steel will expand at different rates this kind of adhesive will be ideal,

 

[Fallon]

They make tape that will work, IIRC, 3M calls it VHB tape. I would probably use pop rivets though.

Aaron Z

I was about to say that. Its plenty strong to keep solar pannels mounted to the roof hurdling down the road at 75mph. This isnt cheap double sided sticky tape from as n office supply store.

 

[Garauld]

After contacting my local steel distributor, I think I am probably going to use 18 ga (.047") steel sheet on the cab exterior. I can get a 4x8 sheet for about $60. I'll probably plug weld it in place. That should be rugged enough ya think?

 

[ArlyA]

Any material with have its pluses and drawbacks and I'll try list "some" of both below. That is steel and plastic, (HDPE and ABS and these two plastics are pretty different from each other)

Steel might rattle against your frame, has poor to no insulation capability and no sound absorption. I am worred that steel might make your cab into a horn. Pluses is it excepts paint well and you can tack weld it on.

ABS or HDPE. Does have heat and sound insulation capabilities. Easy to cut a hole in it later that you'll inevatilbty need to do. Lighter in weight and easy to drill into or cut during its construction. ABS can readily be glued, but HDPE can not. Either you can heat and form it, although I'm not all that good at it! Negatives are, neither material ABS or HDPE like to be painted but you can do that.

What I'm I forgetting??!!??!!

After contacting my local steel distributor, I think I am probably going to use 18 ga (.047") steel sheet on the cab exterior. I can get a 4x8 sheet for about $60. I'll probably plug weld it in place. That should be rugged enough ya think?

 

[Garauld]

I will probably use VHB tape to bond HPL (Formica) to the inside walls. HPL expands about 2x the amount steel does per °F. ABS is about 6x.

 

[airbiscuit]

Why inside walls?

 

[Garauld]

Why inside walls?

It has to look good! I was going to add 1" insulation for when I add the heater system and the inner walls are to protect it..

 

[ArlyA]

Personally, I'd be cut sections of ABS to fit portions of the cab. Before attaching them, glue some cab foam to the entire pieces back side which will be on the cabs inside. This would add both sound and temp insulation then pop riveting it on would make for easy repairs later. Cab insulation is basically closed cell foam and readily available and is a very nice material to work with. I've got lots of it laying around here and love using the stuff. I believe Formica is a sound resonator.

 

[airbiscuit]

Personally, I'd be cut sections of ABS to fit portions of the cab. Before attaching them, glue some cab foam to the entire pieces back side which will be on the cabs inside. This would add both sound and temp insulation then pop riveting it on would make for easy repairs later. Cab insulation is basically closed cell foam and readily available and is a very nice material to work with. I've got lots of it laying around here and love using the stuff. I believe Formica is a sound resonator.

Foam insulation on the inside would be more quiet, would be softer to slam your head against, and a smooth exterior would shed water better than all those exposed frame members.

 

[MossRoad]

I'd put styrofoam-type panels inside the doors and fiberglass gel coat it. Warm and quiet.

 

[Garauld]

I am thinking using 1" rigid foam board insulation spray glued to the outside sheet steel panels. Instead of the HPL, I could attach a layer of thin headliner fabric spray glued onto the foam and framing members. That would probably quench the sound levels.

 

[PILOON]

I have a bit of experience with sound deadening from my aviation background.

There are different levels of sound and different causes.
Any large metal panel will 'resonate' and also it will 'drum'
One commercial material readily available and cheap as well is self adhesive roofing membrane, stick that on the inside and results will be awesome. (even a large X on the panel area will be helpful)
In the engine area, firewall, a high density foam material will be best to deaden that engine noise. Lead is also a great sound blocker.
Surprisingly carpeting is also great for many ranges of sound.
AS to insulation (LOL, not isolation) most foam boards do very well, even as little as 1/2 or 3/4 inch.

On my CUT I did most as I described and never wear hearing protection plus I can tune in my favorite FM station to enjoy nice music at reasonable volume settings.

In my case I never welded my panels but drilled and used self tapping screws since I did not want to grind and feather those weld joints.
I also used galvanized sheet stock for paneling as that never rusts.
I also injected some oil inside of the tubing framework so as to not have corrosion happen. (again an aircraft technique)
Going on close to 20 years and no rust anywhere and still completely water tight (and, LOL, quiet.)

Nice project, keep us posted!

 

[Garauld]

I wonder if vinyl fabric would reflect much noise or deaden sound somewhat if installed on the inside cab walls. It is rather inexpensive and would be easy to install. I don't expect much engine noise in the cab - the engine is located in a separate compartment at the rear. I would expect the most noise to come from the diff under the cab floor. There will be a rubbery floor mat covering the floor plates (12 ga - .108" sheet).

 

[PILOON]

I wonder if vinyl fabric would reflect much noise or deaden sound somewhat if installed on the inside cab walls. It is rather inexpensive and would be easy to install. I don't expect much engine noise in the cab - the engine is located in a separate compartment at the rear. I would expect the most noise to come from the diff under the cab floor. There will be a rubbery floor mat covering the floor plates (12 ga - .108" sheet).

If U add some felt padding under the vinyl it probably would work.
Even some padding like they sell for under laminated flooring would be good.

On its own the vinyl won't do much good.

 

[Garauld]

Not much exciting stuff to report but here goes: I finished the wiper design and welded in the bracket for the repurposed GM Blazer rear wiper motor. I had to extend the stock wiper arm by 1-1/2" to make it work per the attached image. I also welded in a bunch more cab frame members and started hanging sheet metal skins on the cargo and cab framing. I also finished up the design of a moon-roof I will be adding. The pop-up latch came from a mid-80s Toyota 4-Runner pickup. I designed some custom hinges which I will have 3D printed by a buddy of mine.

 

[Garauld]

I've been adding sheet metal to the cab and cargo frames. I hope to spray some primer and paint this weekend on the tub, cargo subframe and cab undersides.