Air Pressure

[tkhudson]

I seem to recall Nick saying something in Sawdust sessions about sawdust accumulation sucking the grease out of the bearings... seems like a long shot, but it sounded good to me

Can anyone tell us they have found accumulations of sawdust inside their headstocks? Since I've never found any, I am wondering why this concern exists.

[billmayo]

I had cut a 4" round hole in the end of the motor pan to allow a longer DC motor with better cooling. When I quit playing with the DC motors, I put a square 4" louvered and screened vent over the hole and used a regular Shopsmith motor. The headstock ran cooler. When I checked after several years of operation, there was no sawdust inside the headstock. It greatly increased the air flow from the vent on the bottom of the motor pan.

The bottom vent in the motor pan will prevent the buildup of any pressure in the headstock but does create a very slight negative pressure that helps suck sawdust through any small opening in the headstock. Output air area is greater than input air areas.

[cv3]

I just did a spring cleaning of the shop that included the SS. I had not really cleaned it for about 6 months and it got a lot of use the 3 months before Christmas. There was very little sawdust in the headstock. That may be because I always use my dust collector.

[vzandt]

I am just finishing the rebuild of an '83 model MK V that was packed with sawdust. Once I emptied the headstock casting, I user a pressure washer to clean out the encrusted sawdust. It can out in chunks that looked like particle board that got wet. The reason I got the machine was the previous owner caught the motor on fire. The sawdust accumulation inside the motor caught fire and destroyed the motor. There doesn't appear to be any extra openings or anything to explain the buildup, but I'll monitor it once I get it back in service.
Scott

[reible]

Hi,

I got a basket case 510 that had a great deal of saw dust collected inside and it was packed in tight. I had to get use a dowel to dislodge it. Some was in areas where I could get to it so I had to drop the pan and remove the motor to clean it up.

I have never seen that problem with my original headstock I got in 1976 but then I keep it cleaned out as part of proper maintenance. I'm guess by the general condition of the machine the previous owner(s) didn't do much of that.

I did find the washer out of the back of the single bearing quill in the sawdust as well as the reason the quill would not lock... yep that washer too. So you might want to see what is in the dust pack before disposal.

Now that I have the machine the saw dust inside is the same as my other machine so I have to guess that it went for years without it getting cleaned out, not that it had an outstanding issue with retaining dust.

Ed

[tkhudson]

I had cut a 4" round hole in the end of the motor pan to allow a longer DC motor with better cooling. When I quit playing with the DC motors, I put a square 4" louvered and screened vent over the hole and used a regular Shopsmith motor. The headstock ran cooler. When I checked after several years of operation, there was no sawdust inside the headstock. It greatly increased the air flow from the vent on the bottom of the motor pan.

The bottom vent in the motor pan will prevent the buildup of any pressure in the headstock but does create a very slight negative pressure that helps suck sawdust through any small opening in the headstock. Output air area is greater than input air areas.

Perhaps a simpler solution to the problem, if one does exist is to place some filter material around bottom vent to clear the air coming in?

[JPG]

Perhaps a simpler solution to the problem, if one does exist is to place some filter material around bottom vent to clear the air coming in?

I think the best use of an air compressor would be to blow out the interior of the headstock periodically. Nick did so with it running through the 'medallion' hole.(Sawdust session #?)

[tkhudson]

I think the best use of an air compressor would be to blow out the interior of the headstock periodically. Nick did so with it running through the 'medallion' hole.(Sawdust session #?)

Probably so, but it was good to hear all of the opinions on the subject.

[robinson46176]

Some of the differences in amount of sawdust and if it is impacted may have more to do with the kind of wood being cut and in some cases how dry it is. Some high rosin pine especially if it is quite fresh can almost become particle board without glue.