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Morris

Morris

Yoda
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This actually relates to my Midget, but I am going to keep how it relates to my Midget a secret for right now...

So I am working with aluminum bar stock, and the target "thickness" for the part I am making is 5/8". Would there be a significant difference in structural strength if I combined a 3/8" and 1/4" piece as opposed to a using a single 5/8" piece?
 
There would be a significant difference. The only way it might work is if it could br furnace brazed to insure a bond across the entire mating surfaces. I am sure Home Depot or McMaster Carr can supply you with the correct thickness material.
 
If is a small part, why not loss wax the part and melt the aluminum and cast it? Just an idea, have made fencing handles that way.

Here is the loss wax process:
https://www.pbase.com/mjcall/gallery/casting
This shows jewelry making but it works for aluminum too.

But I would have to agree, a solid 5/8" would be more structurally sound.

Hope this helps
Ɛan
 
You gave us insufficient information to know the effect of laminating the assembly. Generally the answer would be "two pieces are weaker" but that must be tempered with whether the parts are loaded in tension, torsion, or loaded in flexure like a beam. If in doubt, as stated above, there are lots of places from which you can buy a single solid piece of aluminium.
 
So Morris what are you trying to make? Curious minds want to know?
 
I made front bracket hinges for my Bugeye Bonnet from 3 pieces of aluminum plate rather than from a single 1/4" plate. I ended up 3/8" thick and bonded all together with JB Weld. Works so far. Roughed out plate, bonded together, clamped, and then finish work performed on bonded piece. Now I had some 1/8" aluminum scrap in the shop, if I'd had 1/4" I might have made from a single piece. Exta washers under there and bonnet does not know the difference.
 
It looks like the single solid piece of aluminum is the way to go. I figured as much, but I wanted to check with the experts. Using two pieces would make the "machining" a little easier and make for a slightly prettier installation.

And what it is: I made a bolt-on front tube shock mount kit. However, there is a small amount of flex in the top mount. I am working through the most economic means of improving the top mount.

I didn't want to mention this before because I did not want to spark ye olde tube vs. lever shock debate before I got the good info from the brilliant minds.
 
Well, they glue Lotus, Aston Martin, and other chassis including Fighter jests, together so if you find the right adhesive etc., you're probably o.k.
 
/bcforum/images/%%GRAEMLIN_URL%%/lol.gif
Cars & aircraft made of 'frozen snot'!!! /bcforum/images/%%GRAEMLIN_URL%%/smirk.gif

PANEL BOND adhesive!
 
I have a 400lb mill/drill press and metal lathe, if you provide dimensions I might be able to make what you seek.
Ɛan
 
/bcforum/images/%%GRAEMLIN_URL%%/shocked.gif

Dan! You're my new BESTEST FRIEND!!! /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
My kids do that when they want somthing /bcforum/images/%%GRAEMLIN_URL%%/nonono.gif
LOL
 
I can pretty easily make what I need...

but is it okay if I hit you up for another project?
 
Sure what is it?
Ɛan
 
He's got plans for an independent space shuttle... /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
Morris, make sure you use the proper grade of aluminum. I'd suggest 7075T-651.
It's not weldable, but it's very strong and machines beautifully.
Jeff
 
Morris:

Jeff's recommendation is better but 6061 is decent, may be easier to find and it may be acceptable for your use. Both of these material are generically referred to as "aircraft aluminum".

Here's ASM data on both.

https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MA7075T6

https://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MA6061T6

I am guessing that you have seen the page with my tube shock mod. My upper shock mounts are 1/4" thick extruded AL of unknown material (but probably 6061). They have worked fine but came loose at (bumpy) Lime Rock once. I have since added a larger steel-plate backing pad (1/8") on the backside of the chassis mount area. I also glued the shock mount in place with PL200 construction adhesive to reduce "creeping" (I use this stuff in many areas of my car). I used two 1/4"-28 bolts (Grade 5) to attach the shock mounts to the car.
So far, works good with 100+ racing hours on it.
Minor issue in my design is clearance from caliper to shock at full-lock. I'm careful when parking and other slow speed turns...not a problem at normal race speeds.

https://npmccabe.tripod.com/spritetubeshock.htm
 
Ah, other widdlers on the forum, cool, I have a Bridgeport mill, and a Rockwell 14x60 lathe, I like widdling myself /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
I own a complete professional aerospace/semi-con machine shop. Send me a sketch and maybe I can help?
https://www.pgage.com
 
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