Shopsmith Forums

Just found an old post of yours from July 2010 that included these pictures of the 610 jigsaw air blower balls and springs(!)

I understand how the air blower works now, but on my machine one of the holes has a black rubber plug in it & the other is empty, with no balls or springs. Not sure if my saw was just built differently (it's serial number puts it in the 1960 - 1961 range) or is missing something courtesy of the previous owner, but can't figure out why one of the holes is plugged.

Do you know of anyone who could part this assembly out to me?
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Those are the nylon balls. I'll try and unpack mine this weekend if I get some time to mic them for size. I remember checking them and they were close to 6mm (plastic bb size) or at least very close. Those springs don't have to be very strong, a ball point pen spring might work or you could make your own with music wire.

Yep - it looks like there is also an aluminum collar ball seat on the top of the outlet hole (the hole closest to the air tube connection). There is also probably a ball seat on the bottom of the inlet hole not visible in the picture. I'm guessing the ball positions are reversed on the inlet/outlet holes (inlet ball on bottom with spring above / outlet ball on top with spring below) for the check valves to work correctly. The inlet hole is the one that has the black rubber plug in it on my machine. My guess is that early versions of the 610 jigsaw blower had balls & springs but users complained when they clogged quickly so the manufacturer just removed them in later models, plugged the inlet hole, & settled for air going both directions instead of pumping air in the inlet hole & out the outlet hole using the nifty check valve setup that some clever Magna design engineer came up with.

I am wondering if you could just use an aquarium in-line check valve.
In the later version that lacks the "balls" is it possible there is a check valve is built into, 3243 fitting-air, instead.

Alright. The little nylon ball measured .248" and 6.31mm. the spring is just a bit smaller to help hold the ball captive while it bounces in the little chamber. A 6mm airsoft bb measured .232" and 5.9mm. It is smaller by .016", however, I think it'd make a good substitute.
I did a quick manual pump check and I didn't notice it failing to work. As a side note, the pump has a build in safety and pressure relief hidden in plain sight. The keyway cut out in the first picture above helps to prevent too much air building up in the case of a clogged exhaust port and also helps in drawing air in above the intake. I'm working on building a test fixture to measure these findings and to see if there are improvements to be made or if a good cleaning is all it takes.

I'll get to posting those soon as free time is available

Wow - that's an elegant, simple solution! I didn't know about aquarium pump check valves, but see a clear plastic one on line for only $5. This has the added benefit of making the clog point visible & easy to clean/replace. I'll have to get one ordered. Thanks!

BTW, what do you mean by "3243 fitting-air"?

rpd wrote: Mon Jan 10, 2022 2:28 am I am wondering if you could just use an aquarium in-line check valve.
In the later version that lacks the "balls" is it possible there is a check valve is built into, 3243 fitting-air, instead.

Looks like there are multiple solutions to this problem - thanks!

ShoptimusPrime wrote: Mon Jan 10, 2022 7:14 pm Alright. The little nylon ball measured .248" and 6.31mm. the spring is just a bit smaller to help hold the ball captive while it bounces in the little chamber. A 6mm airsoft bb measured .232" and 5.9mm. It is smaller by .016", however, I think it'd make a good substitute.
I did a quick manual pump check and I didn't notice it failing to work. As a side note, the pump has a build in safety and pressure relief hidden in plain sight. The keyway cut out in the first picture above helps to prevent too much air building up in the case of a clogged exhaust port and also helps in drawing air in above the intake. I'm working on building a test fixture to measure these findings and to see if there are improvements to be made or if a good cleaning is all it takes.

Matanuska wrote: Tue Jan 11, 2022 11:51 am Wow - that's an elegant, simple solution! I didn't know about aquarium pump check valves, but see a clear plastic one on line for only $5. This has the added benefit of making the clog point visible & easy to clean/replace. I'll have to get one ordered. Thanks!

BTW, what do you mean by "3243 fitting-air"?

rpd wrote: Mon Jan 10, 2022 2:28 am I am wondering if you could just use an aquarium in-line check valve.
In the later version that lacks the "balls" is it possible there is a check valve is built into, 3243 fitting-air, instead.

"3243 - fitting-air" is the reference for the part in the exploded parts diagram/list in the manual

http://vintagemachinery.org/pubs/detail.aspx?id=10571

I'm in the process of refurbing a Magna jigsaw. The puffer assembly contains no springs or balls at all, otherwise it looks like the picture above (with no aluminum ring to hold the ball in place). I guess I'll just have to do without!
I suspect you guys are right, they just stopped putting the check valve in due to clogging problems - or possibly to save $0.04 per jigsaw....

The downside, of course, is that every time the spring retracts pulling the blade up, you're actually sucking dust from the table back into the upper assembly.
Maybe I'll just add an aquarium pump, like I did for my scroll saw.

Plug the puffer hole.