Shopsmith Forums

Regarding the puffer: Does the tube separate from the lower aluminum part(s). Do they get plugged up? There appears to be a check valve on the bottom to allow air entry, but is there another valve internal?

TIA

After PMing Bill Mayo and learning he had several of them, I decided to get more aggressive re disassembly. I got the impression from his reply that he had never taken one apart before, but did say he had not had any that worked well(inadequate air 'puffing').

After first an unsuccessful attempt to unscrew them apart, I tried driving them apart. This was also unsuccessful, but did reveal how it was secured. There are two dowel pins(steel) passing through the walls of the steel tube and driven into holes in the aluminum part. I drove these pins INTO the open center of the aluminum part thus allowing removal of the dowels. Those dowels were invisible prior to moving them slightly by the driving off attempt. An undesirable result of trying to drive them off was to create a small burr at the edge of the holes in the tube(where it pushed against the dowel during driving attempt). Those burrs scored the aluminum part when parting them.

So my initial questions have been answered. There are indeed two valves in the lower parts(an intake and an output ball check valve). The intake valve is visible looking up towards the bottom. The output valve is hidden, but the spring is visible through the output port threaded hole.

I believe after the gasket is replaced and the valve parts cleaned up that it may work satisfactorily again(assuming the damage done is not critical).

Pix follow:

[ATTACH]9723[/ATTACH] [ATTACH]9724[/ATTACH]

I have reached these 'conclusions'.

1) The gasket becomes leakey and reduces the air flow.

2) Since it is sop to occasionally oil the pump piston by adding oil from the top, deposits of oil are left in the lower assembly and unfiltered air enters from the intake port, a buildup of crud occurs around the valve balls/seats. If inactive this hardens to that stuff we all know only too well. Stickey valves reduce the air flow.

3) Inactivity causes the piston(leather) to dry up and shrink. Leather conditioner seems to restore pliability.

The deed is done(for better or worse?). The attempt to drive it apart without first removing the dowel pins(who knew they were there?) caused the holes in the tube/lower assembly to slightly enlarge. After reassembling it (with a new replacement gasket), the assembly was loose.

To compensate for the hole(s) slop, I trimmed the old gasket to a ring (washer) shape and slipped it over the projection of the lower assembly that is inserted into the tube. This took up the added slop.

[ATTACH]9739[/ATTACH]

I placed a drop of thin CA on each dowel pin to prevent them drifting in/out(time will tell!).

FWIW the puffer does not move a lot of air. When checking for flow at the tube, not much is apparent. When that flow is concentrated through the nozzle behind the blade, it does blow the sawdust out of the way!

While we are on the subject of jig saws, The pix below illustrates how I make a crankcase gasket. I only punch 5 holes in the gasket. 4 for the mounting screws, and ONE for the bleeder/breather. This places oil on only one side of the gasket(the crankcase side). The cover side will not have any oil(unless the saw is tilted upside down and the oil leaks through the bleeder hole). Thus only one gap to leak through!

[ATTACH]9740[/ATTACH]

Thanks for the info on photos. This will be good information when I tear into mine!

Somehow this is very timely. Since I just purchased a new unused unit and had trouble with the table adjustment knob i decided to take the whole Jigsaw apart to see how it works and these pics help tremendously. It looks like the lo Lower Assembly has never had oil so I'm off to see if I can find some 10 weight oil.

putttn wrote:Somehow this is very timely. Since I just purchased a new unused unit and had trouble with the table adjustment knob i decided to take the whole Jigsaw apart to see how it works and these pics help tremendously. It looks like the lo Lower Assembly has never had oil so I'm off to see if I can find some 10 weight oil.

Look for air compressor crankcase oil.