Shopsmith Forums

I got a new to me DC3300 off of Craigslist. it seemed to run and suck fine when I checked it out in the seller's garage. they had been using it with a metal vacuum cleaner S-curve to suspend the pick-up just above the floor and roll it around to clean up the shop.

when I used it for the first time last night, I noticed that it sounded different than the older one that I had but it seemed to be sucking fine as I was cleaning up some dust off a table top. after a minute or 2, there was a bang and rattling sound and then a sharp odor. I now think that odor was melting plastic. the suction dropped to almost nothing.

I cut it off and tried to check it out. when I couldn't find anything, I started digging in. the online pdf of the DC3300 manual does not do a full component breakdown and there is no information for getting to or replacing the impeller. the parts list does not seem to match what is inside this DC. the fan housing is completely different. the switch on the one that I am working on is in a housing with louvers at the base of the motor.

I got as far as removing the top filter bag and the part of Fan Housing that diverts the air flow down into the bottom bag.

all of the blades are there on the impeller and I can turn it by hand. I am not sure how freely it should turn. there are thin slivers/sheets/films of plastic coming out between the back of the impeller and the motor side of the housing. if I plug it in and turn it on, the impeller turns, but I think that it is dragging on something and melting the backside of the impeller. the impeller looks to be nylon.

the dis-assembly procedure is not obvious to take the impeller off. I am guessing that I take out the 4 screws holding the inlet adapter to the fan housing and slide it toward the 3-way inlet. if it slides far enough, then I should be able to take out the screws holding the front and back portions of the fan housing together and remove the front half to get access to the impeller.

does anyone know if that will work?

if so, what do I need to do to get the bolt out of the impeller without breaking it?

any guesses what I am going to find once I get the impeller off?

I did a search here but could not find any threads on replacing the impeller other than someone who had had the impeller bolt break twice.

I tried taking some pictures through the fan housing outlet, but they didn't turn out well.

does the replacement impeller come with instructions?

Ivan

Bob,

thanks.
the pics through the outlet did not work, but the overall pics were okay. here is what mine looks like.
[ATTACH]6943[/ATTACH]

[ATTACH]6944[/ATTACH]

Thats what mine looks like.....caused some discussion in a earlier post.....you've got a very early model.

etc92guy wrote:Thats what mine looks like.....caused some discussion in a earlier post.....you've got a very early model.

thanks for the info and the mention of the earlier thread.
I had forgotten about reading that thread.

FWIW, the DC3300 that came with my first '89 510 has the switch in the "modern" location on the leg. I had naively hoped that the one that I just got was the newer model. the leg location is definitely easier to reach from the front of the machine, but the wiring seems much more exposed there.

Ivan

Iclark
That's what mine looks like also. I think it is easier to get to our impeller with this design. I didn't know they moved the switch. Once you remove that plastic shroud, if I remember correctly, what you need to do next will be obvious. Before I got real excited about tearing into it I would make sure you didn't pick up something for the floor that got wrapped around the impeller or it's shaft. I had a piece of plastic get wrapped and it made a similar situation to the one you describe.

thanks all for your inputs.

Ed, I just saw your reply, but I certainly agree with your sentiment. I fully expected to find something in behind the impeller when I started taking things apart.

I did not find anything beyond a reasonable amount of dust behind the impeller. there was one spot of the fan housing (against the back of the impeller) that had some plastic adhered to it.

here is what the impeller looked like:
front
[ATTACH]6964[/ATTACH]

hub front
[ATTACH]6965[/ATTACH]

rear
[ATTACH]6966[/ATTACH]

sorry about the poor foto quality. they were taken with my pocket X-1. (it seems to have focusing problems unless there are some sharp edges with high contrast near the foto center)

the impeller looks to be nylon with a brass hub inserted from the rear. the hub is keyed to the shaft (Woodruff key?). I am guessing that the sound that I heard was one or more of the cracks opening up and that let the centrifugal force on the blades flex the disk back against the fan housing where friction melted some of the nylon.

I think that I have an impeller spare buried on a shelf (ordered after I got the first DC3300 because it is on the top-17 parts list). I plan to call customer support tomorrow to get another spare on the way and to double check that both versions of the DC3300 take the same replacement impeller. the one in the online catalog looks _very_ different.

any pointers (or gotchas to avoid) would be welcome.

Ivan

Ivan
Have you tried to run the DC without the impeller to insure your problem isn't in the motor assembly?

Actually I didn't think your impeller looked all that bad. But perhaps it was the picture quality. The rub marks on the back side where are they in relation to the largest cracks? If they are about 90 degrees to each other then I would quess your thoughts on the matter are right. The whole impeller disk is flexing back and rubbing something.

Being the cheap guy I am I would try epoxying the cracks shut. Then I would have a great time trying to balance the whole mess but hey I would be playing in the shop instead doing something my wife wanted and that would be a good thing

Ed in Tampa wrote:Ivan
Have you tried to run the DC without the impeller to insure your problem isn't in the motor assembly?

Actually I didn't think your impeller looked all that bad. But perhaps it was the picture quality. The rub marks on the back side where are they in relation to the largest cracks? If they are about 90 degrees to each other then I would quess your thoughts on the matter are right. The whole impeller disk is flexing back and rubbing something.

Being the cheap guy I am I would try epoxying the cracks shut. Then I would have a great time trying to balance the whole mess but hey I would be playing in the shop instead doing something my wife wanted and that would be a good thing

Titebond (I think its Titebond) makes two or three varieties of ca adhesive. The thinner one is designed to migrate into the cracks. Would that work. Maybe this is what Ed was talking about, too. It may be epoxy I am thinking about and now a ca ...or whatever.