Snow Tandem Engine
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Hi all
Got started on the coolant pump. The plans called for using a submersible electric pump in the reservoir, didn't much care for that, so after asking a few questions of Rustkollector (Jeff) decided to go with Jerry Howell's magnetic drive pump. Of course, I can't just follow the plans, so there have been a few modifications already... ;D ;D
I didn't have an appropriate piece of round stock, so soldered a temporary spigot on a chunk of my secret stash of 1/2" plate brass, and then turned the spigot so it would run true
Turned it round, reversed it in the chuck and machined off the spigot in the process of hollowing out the piece, then silver brazed it to a piece of flat stock.. (I've been reading a lot of posts about silver soldering lately, so I greatly reduced the amount of silver solder as compared to my previous practice... seem to have gotten it just right. Thanks to all who have been posting tips on this arcane art!)
(and, if you look closely, just behind the firebrick you can see the first one, stuffed it up drilling the bolt circle....)
in the pickle.... looks like I need to top up the supply
Jerry's plans call for a delrin piece threaded into the brass body to hold the impeller in place. I still don't have a thread-cutting lathe, so left the hole in the pump body un-threaded, will also not thread the delrin insert, and will hold it together with this clamping ring
Next up is the impeller, turned the blank with a shoulder on the bottom to facilitate holding it on the rotary table with a strap of spare ali, off-set it to mill the slots, re-centred and drilled the holes for the magnets, after this re-chucked it in the lathe and turned off the shoulder
and here is the delrin piece ready for parting off. First time I've machined this stuff, boy it sure cuts easily with a nice finish. Nice soft non-cut-causing swarf, too
Made the pulley for the thing, and then added it to the pile of parts that don't fit, so next up will be another one.... and inlet & outlet bits.
Cheers, Joe
Got started on the coolant pump. The plans called for using a submersible electric pump in the reservoir, didn't much care for that, so after asking a few questions of Rustkollector (Jeff) decided to go with Jerry Howell's magnetic drive pump. Of course, I can't just follow the plans, so there have been a few modifications already... ;D ;D
I didn't have an appropriate piece of round stock, so soldered a temporary spigot on a chunk of my secret stash of 1/2" plate brass, and then turned the spigot so it would run true
Turned it round, reversed it in the chuck and machined off the spigot in the process of hollowing out the piece, then silver brazed it to a piece of flat stock.. (I've been reading a lot of posts about silver soldering lately, so I greatly reduced the amount of silver solder as compared to my previous practice... seem to have gotten it just right. Thanks to all who have been posting tips on this arcane art!)
(and, if you look closely, just behind the firebrick you can see the first one, stuffed it up drilling the bolt circle....)
in the pickle.... looks like I need to top up the supply
Jerry's plans call for a delrin piece threaded into the brass body to hold the impeller in place. I still don't have a thread-cutting lathe, so left the hole in the pump body un-threaded, will also not thread the delrin insert, and will hold it together with this clamping ring
Next up is the impeller, turned the blank with a shoulder on the bottom to facilitate holding it on the rotary table with a strap of spare ali, off-set it to mill the slots, re-centred and drilled the holes for the magnets, after this re-chucked it in the lathe and turned off the shoulder
and here is the delrin piece ready for parting off. First time I've machined this stuff, boy it sure cuts easily with a nice finish. Nice soft non-cut-causing swarf, too
Made the pulley for the thing, and then added it to the pile of parts that don't fit, so next up will be another one.... and inlet & outlet bits.
Cheers, Joe
Deanofid said:
Yup. Yer close. Real close. In fact, pretty much right on the mark. :big:
This is one of those "how much of this do I show?" bits, Jerry Howell's plans are still copyright and available for sale....so don't want to go overboard with too much detail, but on the other hand, there are only so many ways to stick an impeller in a housing to move fluids...
Joe.
Dean: Better stop now while you're at 100% :big:
Hopeless: The only info I've seen on that has them being used on a pipe-line. Presumably could have been used anywhere one needed low rpm/high torque for long periods?
Got a bit further with the pump:
Turned the driven pulley that in turn moves the impeller. Looks like a real simple part, huh? This danged thing took me three tries: overbored the hole for the bearings in the first one, the tool grabbed the second one out of the 4-jaw and tossed it across the shop leaving un-recoverable dings, the third one came out OK
Then turned the driving pulley, this one worked out first time :
soldered the inlet and outlet to the pump body
made up a mounting bracket, here it is with the rest of the parts
And here they are stuck together.
Still have to test it moving some fluid, and then mount it on the base of the engine.
Cheers, Joe
Hopeless: The only info I've seen on that has them being used on a pipe-line. Presumably could have been used anywhere one needed low rpm/high torque for long periods?
Got a bit further with the pump:
Turned the driven pulley that in turn moves the impeller. Looks like a real simple part, huh? This danged thing took me three tries: overbored the hole for the bearings in the first one, the tool grabbed the second one out of the 4-jaw and tossed it across the shop leaving un-recoverable dings, the third one came out OK
Then turned the driving pulley, this one worked out first time :
soldered the inlet and outlet to the pump body
made up a mounting bracket, here it is with the rest of the parts
And here they are stuck together.
Still have to test it moving some fluid, and then mount it on the base of the engine.
Cheers, Joe
Dean: You're still riding at 100% :bow:
Sam: going with the entirely basic empirical "spin it and see if it moves some fluid" type of testing... I've SEEN pump curves on paper, and cheerfully admit that the generation of such an animal is beyond my ken. (And the interpretation thereof as well ??? )
Joe
Sam: going with the entirely basic empirical "spin it and see if it moves some fluid" type of testing... I've SEEN pump curves on paper, and cheerfully admit that the generation of such an animal is beyond my ken. (And the interpretation thereof as well ??? )
Joe
Chicken, Dean? Rof}
Jeff: the pulley is called out as brass or aluminum, as it has a matching array of magnets countersunk in the inside rim to work with the magnets in the impeller. The whole point here to avoid the need for a through shaft with the ensuing sealing problems.
Cheers, Joe
Jeff: the pulley is called out as brass or aluminum, as it has a matching array of magnets countersunk in the inside rim to work with the magnets in the impeller. The whole point here to avoid the need for a through shaft with the ensuing sealing problems.
Cheers, Joe
Dean: it's smoke and mirrors. Never forget the smoke....
Got the bench test done on the pump, we have circulation! Here's a very short video thereof...
Here it is stuck in place
And with the flywheel in place. The clearance was dictated by the belt I had on hand.. sometimes ya gits lucky!
the other side
not much left now...
Joe
Got the bench test done on the pump, we have circulation! Here's a very short video thereof...
Here it is stuck in place
And with the flywheel in place. The clearance was dictated by the belt I had on hand.. sometimes ya gits lucky!
the other side
not much left now...
Joe
Joe,
Your magnetic drive pump is very nice.
For your pump test, see how high the water can be pumped.
The difference in elevation between the suctions liquid level and the height of the discharge liquid will give you the feet of head. 2.31 ft of water head is equal to 1 psi.
You can also measure the volume by pumping from or to a graduated cylinder to determine GPM (gallons per minute) or litres per fortnight. :big:
Regards,
SAM
Your magnetic drive pump is very nice.
For your pump test, see how high the water can be pumped.
The difference in elevation between the suctions liquid level and the height of the discharge liquid will give you the feet of head. 2.31 ft of water head is equal to 1 psi.
You can also measure the volume by pumping from or to a graduated cylinder to determine GPM (gallons per minute) or litres per fortnight. :big:
Regards,
SAM
Sam
Thanks for that! I had no idea how to quantify the output. Now, of course, I'll have to try that out....
In the video it was running with a 2" drive pulley at 500 rpm. When I increased the speed to a nominal 880 rpm, the output stream was going markedly further with greater pressure... now I can put some numbers on that... thanks again, much appreciated.
This sort of input is why I like this place Thm:
Cheers, Joe
Thanks for that! I had no idea how to quantify the output. Now, of course, I'll have to try that out....
In the video it was running with a 2" drive pulley at 500 rpm. When I increased the speed to a nominal 880 rpm, the output stream was going markedly further with greater pressure... now I can put some numbers on that... thanks again, much appreciated.
This sort of input is why I like this place Thm:
Cheers, Joe
Thanks, Richard.
Needed to tie down the coil next to the pump, so made up a clamp on a foot that screws down on the wooden base
and here's things no longer flopping around
Things are likely to slow down a little bit, as I'm on vacation as of tomorrow evening, and will be in and out of town for the next two weeks. Shop time will happen, just a little intermittently.
Cheers, Joe
Needed to tie down the coil next to the pump, so made up a clamp on a foot that screws down on the wooden base
and here's things no longer flopping around
Things are likely to slow down a little bit, as I'm on vacation as of tomorrow evening, and will be in and out of town for the next two weeks. Shop time will happen, just a little intermittently.
Cheers, Joe
