rough cost estimate for machining

[4U2QUIK]

An impact gun may not work in that system because of the slack. And if you really wanted to torque on those you would need something to support the whole machine or else it would just pop off when you try to torque the lugs. You would need like a leg, or a jack under it, if the lugs were tough. Its a cool design and all, but do you really have to get it built? It seems a bit impractical

not likely, my biggest concern is the materials being used. Aluminum is perfect for the housing and cover plate, but I'm very certain that you are going to have issues with the 1045 steel parts when using a impact gun. I'd use someting more like etd150 or stressproof (4340ht?). The repeated impact is going to be a much greater stress than the 400lbs or so that you'll need to properly tighten the lugs. the shear and tensile strenght on the books looks good for 1045, but you can't forget about elasticity of materials, or the lack thereof.

 

[teamslow]

not likely, my biggest concern is the materials being used. Aluminum is perfect for the housing and cover plate, but I'm very certain that you are going to have issues with the 1045 steel parts when using a impact gun. I'd use someting more like etd150 or stressproof (4340ht?). The repeated impact is going to be a much greater stress than the 400lbs or so that you'll need to properly tighten the lugs. the shear and tensile strenght on the books looks good for 1045, but you can't forget about elasticity of materials, or the lack thereof.

thanks for the information. everything seemed fine when i ran the analysis except for the input shaft. the input shaft was failing, but i thought i was just constraining it wrong. How much more expense would the material be for etd150? is Etd150 an alloy or is it a process used to stressprof a material? Thanks again

 

[teamslow]

4U2QUIK

what would you reccomend to be a good interference tolerance between the housing and the bearings and the shafts and the bearings? I want the bearings to be press fitted onto the housing and the shafts press fitted on the bearings.


Thanks,
Marc

 

[JASONA70]

WTF did you get that price from?
Try closer to 300-500$
Just the body is going to cost that much because You need to purchase 9" round aluminum which is special order, and you have t0 buy 1 foot minumum. That's right around 200$ right there.

I was thinking of my machine shop class. I usually fabricate my own designs and with a huge discount in the price of material (educational purposes). I'm sure if you were to get this mass produced you wouldn't be asking on an off topic section. You should ask the machine shop class to see if they could help you with this project. You would have to try the advanced machine shop though, the only thing the beginning machine shop kids know how to use is a drill press and the machining lath... :sarcasm: If you are not in a machine shop class, you should sign up for one! its an awesome experience to see your creations come to life.

Post up some of the project specification sheets, like the material for each part and etc. etc. I'm sure I can get some pricing for you.

 

[4U2QUIK]

I'VE BEEN A MACHINIST FOR THE LAST 12 YEARS!
I'm the inspector, and I do job cost estimation at a very successfull machine shop.

 

[adampecush]

...and the factor of safety for each part was all well above 1.

I'd think the minimum should be no less than 2 for something like this where relatively large forces are being applied....

 

[4U2QUIK]

thanks for the information. everything seemed fine when i ran the analysis except for the input shaft. the input shaft was failing, but i thought i was just constraining it wrong. How much more expense would the material be for etd150? is Etd150 an alloy or is it a process used to stressprof a material? Thanks again

it's not that much more, you're probably looking at a 20-40$ difference.

4U2QUIK

what would you reccomend to be a good interference tolerance between the housing and the bearings and the shafts and the bearings? I want the bearings to be press fitted onto the housing and the shafts press fitted on the bearings.


Thanks,
Marc

-.0002 to -.0007 is a nice interfereance fit.

I'd think the minimum should be no less than 2 for something like this where relatively large forces are being applied....

stress analasis programs don't always tell you the whole story, so I would only use it for reference.