Re: [ATM] OT: Machinist Question

["Thomas A. Moulton" <tom@moulton.us>]

Thomas,

Yes isn't it always the way.

I think I may need to pass on a calibrated hose length because
I measure out 1/4 LB (not 1/4 Ton :) ) at a time

Also due to other limitations I will likely try 1" hose
and a very short length (maybe 2") to reduce chance of clogging.

I will post pictures when I have a solution.

Tom

> Hi Thomas,
>
> I read Mike's post and thought "well Duh, isn't it always the simple ideas
> that are so hard to think out?, but when you do see it...." all you now
> have
> to do is build a hopper, and calibrate the "hose".
>
> BTW for that I'd look at "large" diameter medical silicone hosing, the
> stuff
> starts at 1/8" and goes up to about the 1" mark, very squishy stuff
> too.....
>
> Can get a bit pricy though, but as long as it isn't exposed to sun light
> it
> should last a long time (like years).
>
> Cheers, Thomas.
>
> -----Original Message-----
> From: atm-bounces@atmlist.net [mailto:atm-bounces@atmlist.net] On Behalf
> Of
> Thomas A. Moulton
> Sent: Wednesday, 14 February 2007 11:12 PM
> To: atm@atmlist.net
> Subject: Re: [ATM] OT: Machinist Question
>
> Mike,
>
> Thanks for the GREAT Ideas!
>
> I'll have to try to scale it down a bit... 6" Is rather large!
>
> But it does get around a LOT of problems!
>
> Tom
>
>> If you are designing a gizmo to dispense grit, try what we do in the
>> foundry industry to handle sand.  A rubber hose, six inches in diameter
>> and a couple feet long.  Nice soft gooey rubber.  Simply actuate your
>> 'knife' valve control, but the 'knife' has a nice big radius on it so it
>> won't cut the rubber.  It pushes the rubber hose against a flat backing
>> plate and seals the hose off. Works great for abrasives and we only
>> changed the hose every two years.....after running two shifts from 0600
>> to 0200.....almost around the clock handling fresh gritty 60mesh sand.
>>
>> We had two of these 'knives', one would open and fill the space down to
>> the lower, closed one.  Then the upper would close, leaving a charge of
>> sand locked between them.  Known weight.  When the muller called for a
>> sand addition, the timers opened the lower valve, then closed it to
>> begin the loading cycle all over.
>>
>> Should work and it is too easy.  Just like a peristaltic pump, so easy
>> we didn't see it for years...  They handle slurry just fine if sized
>> right.  A better slurry pump is the Sandpiper pump.  Costly though, but
>> I found some small ones for ten bucks each at a surplus place. (they
>> were like a thousand bucks new).
>>
>> Most respectfully,
>> Mike Rock
>>
>> Thomas A. Moulton wrote:
>>> What materials are self lubricating?
>>>
>>> I'm looking to make a knife valve and want to have a material slide
>>> between two others sandwiched together.
>>>
>>> I was thinking of using steel, but that may not work.
>>>
>>> I can not lubricate because dry grit will be passing through the valve.
>>>
>>> Tom
>>> _______________________________________________
>>> ATM mailing list http://www.atmlist.net/
>>>
>>>
>> _______________________________________________
>> ATM mailing list http://www.atmlist.net/
>>
>
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
>

_______________________________________________
ATM mailing list http://www.atmlist.net/