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View Full Version : Hobby machinist job quote needed...



Greg Parent
08-15-2005, 11:08 AM
Hello all,

I have a small machining job I need done and was wondering if anyone in Canada (hopefully near Ottawa, Ontario) would be interested in taking this on. I am approaching this forum hoping I can get a home shop hobbyist interested in making a few bucks from his hobby, as I cannot afford commercial machine shop prices. There is no big rush and I will supply the materials for the job.

I need six donut shaped pieces made from half-inch thick 6061-T6 aluminium plates.

I don’t know if the shape of the stock will cause trouble but I am trying to use what I have and due to financial constraints cannot buy round stock for this project.

The rough specifications for the 6 pieces are as follows:

Thickness = 0.5 inches
Outside diameter = approximately 3.0 inches
Inside diameter = approximately 2.5 inches

There is some variation in the OD and ID of the six pieces but the 3 inch OD and 2.5 inch ID should give you a ballpark figure for what size of machine is needed to handle the work.

Three of the pieces require a series of shallow grooves to be cut on the surface of the inside diameter. The grooves can be concentric or spiral whatever is easier.

If you are interested please e-mail me at grparent@hotmail.com and I will send you the detailed specifications…we can then decide on the rest of the deal.

Thanks for looking…

Greg

snowman
08-15-2005, 12:03 PM
greg,

If you dont want to put the actual final dimensions of the bores, that's fine...but you should put what type of tolerances you want to get. (on the thickness and the diameters)

Good Luck...I'm sure someone here will help for a little extra beer money. http://bbs.homeshopmachinist.net//smile.gif

-Jacob

DR
08-15-2005, 12:29 PM
greg,

I'm sure you'll find someone to do the work.

A suggestion for future projects, especially those in commercial shops, is to not insist on supplying the material. In your current situation it sounds like it might be more trouble (in terms of time, which equals dollars) to use your existing material than to buy round bar.

In my shop I refuse (or charge a whole bunch) to use customer material unless it's clearly marked as to alloy, etc. In the case of aluminum it usually is marked. The worst of the "unknown" metal is stainless bar, which customers frequently will pick up at the scrap yard hoping to save a few bucks. Whatever saving they might realize is sometimes eaten up when it turns out to be very nasty material to machine.

Evan
08-15-2005, 12:43 PM
Greg,

3" heavy wall aluminum tubing with a 0.250" wall is a standard tubing size. If you can work with that it will save a pile of time (and money).

Greg Parent
08-15-2005, 12:47 PM
Good ideas/points Snowman and DR.

The thickness is set by the material thickness I will supply...it is half inch and not a critical value. No machining of this dimension is required.

The final ID and OD are not known yet but will be around the specs I stated. I will give the final values to the interested party as soon as I can. I am missing a critical component that dictates the final dimensions and have to wait until it arrives before I can measure it and determine the remaining values.

As for tolerances, +/- 0.005 should be OK.

Unfortunately I must use what I have or forgo the project. This is why I went the home shop hobbiest route instead of the commercial shop. I figure a no rush, low key project that makes a guy or gal a few bucks is a perfect way to keep my costs as low as possible. The material supplied is 6061-T6 aluminium plate that should machine very easily. The only issue might be its shape. I have some pieces that are rectangular and some that are square. I guess whoever decides to takle the job can figure out an interesting way to make the project a success.

Thanks for your ideas and comments.

Keep em coming.

Greg.

Mcgyver
08-15-2005, 01:13 PM
<font face="Verdana, Arial" size="2">Unfortunately I must use what I have or forgo the project. [/B]</font>

Why, a piece of 3" AL, 1/2 foot long is $25cdn?


<font face="Verdana, Arial" size="2">This is why I went the home shop hobbiest route instead of the commercial shop. I figure a no rush, low key project that makes a guy or gal a few bucks is a perfect way to keep my costs as low as possible.
[/B]</font>


How many few bucks are we talking about? if $25 breaks the bank.....made me think my time is worth more to me that you saving a few $$$ by using the material you have on hand.

my advice is to network and find someone local who will do this because you're a great friend of a friend or it has some philanthropic value, etc. Donating time is one thing, I've worked for free for friends, kids school projects, etc, but wouldn't "hire" out my liesure time for a silly rate

Also, consider giving a hint as to what’s for. It will help people understand what’s required and who knows, maybe you find someone who shares that interest and would like to help out.



[This message has been edited by Mcgyver (edited 08-15-2005).]

Mcgyver
08-15-2005, 01:16 PM
sorry...duplicate

[This message has been edited by Mcgyver (edited 08-15-2005).]

G.A. Ewen
08-15-2005, 02:12 PM
Mcgyver,

Where can this be obtained? " a piece of 3" AL, 1/2 foot long is $25cdn"

Evan
08-15-2005, 02:24 PM
Online metals show 3" OD by .25" wall 6061 T6 tubing at $17.15 per foot. 3" bar stock is $33.55 per foot USD.

Mcgyver
08-15-2005, 02:25 PM
<font face="Verdana, Arial" size="2">Originally posted by G.A. Ewen:
Mcgyver,

Where can this be obtained? " a piece of 3" AL, 1/2 foot long is $25cdn"</font>

being a slow afternoon, and not wanting to step on a cow flap, actually phoned before making that statement. MetalSupermarkets, Concord store. don't have the number anyomore, but its a google away

G.A. Ewen
08-15-2005, 05:09 PM
Evan and Mcgyver,

Thanks for the info. Looks like the local metal supplier has been pulling one over on me.

Paul Alciatore
08-16-2005, 11:24 AM
Local metal suppliers want to sell full lengths. They will cut but there is a charge. Like lumberyards. Go to one and look around. You will see 3', 6', 10', even 18/20' lengths. They may have cuts but that will be kept to a minimum. Special alloys may come smaller but will be more expensive. They aren't hoseing you, it's just the way they do business.

Most shops will have scraps that they can provide for reasonable prices. It was likely paid for in the original job and they are glad to get something for it. They are going to cut (machine it) it anyway so no extra work there. So they are better able to save you money. And they will know what the alloy is so the machining costs can be more easily estimated.

If you are going to machine it yourself, then junkyard scraps may be an option. But, if you are having a part made then I would specify an alloy or alloys that will work and let them supply it.

Oh, and there are on-line suppliers that cater to small shops. They will cut to size. But you may still get a better deal at a local shop.

http://www.asapsource.com/public/index.asp

http://www.metalexpress.net

http://www.metalsupermarkets.com/

http://www.onlinemetals.com/

Paul A.