My new to me Dewalt MBF RAS

[pprobus]

Yesterday, I bought this beautiful little MBF for $75.  

Every point of movement was very hard to move, but some WD-40 freed all of them and everything moves beautifully smoothly now.  I still have to pull the motor carriage out and clean the bearings, but I think they are fine, too, just dirty.  All the knobs are there.  The only things missing are the rip rod and blades wrenches.  It looks the original main table on it, too.  Built from 1955 - 1959, IIRC, that suggests to me it never saw much use in those approx. 65 years.  

Ok, now for the motor.  It runs fine but has a strange sound when stopping.  It doesn't sound like a bearing, and the shaft is firm with no play.  It sounds more like something rubbing.  The bearings have never been replaced, so it's clearly time, but changing them is not the easiest job what with having to carefully pull the fan off.  Regardless, I'd like your opinion on what might be making that sound.  Thanks.  

Link to:  Video

John

If you're not already a member, this forum is the DeWalt RAS knowledge base (hopefully the link works):
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I can't help on the sound. I, too, have an MBF that I need to tear the motor apart to replace the bearings. I just got my 7790 in running shape so that can happen, once I get a couple of other projects off my list.

If you are looking for wrenches, be aware that the size of wrench needed to span the flats machined onto the motor's shaft is 14mm. I know it's kind of odd for a USA made machine from the '50's but that's a fact. I bought a Ryobi router wrench back in the mid 2000's before I knew about Parker bicycle wrenches which are what's recommended on the forum.

Paul

[jteneyck]

If you're not already a member, this forum is the DeWalt RAS knowledge base (hopefully the link works):
https://secure.delphiforums.com/n/login/...t%3d1&sl=y

I can't help on the sound. I, too, have an MBF that I need to tear the motor apart to replace the bearings. I just got my 7790 in running shape so that can happen, once I get a couple of other projects off my list.

If you are looking for wrenches, be aware that the size of wrench needed to span the flats machined onto the motor's shaft is 14mm. I know it's kind of odd for a USA made machine from the '50's but that's a fact. I bought a Ryobi router wrench back in the mid 2000's before I knew about Parker bicycle wrenches which are what's recommended on the forum.

Paul

Parks bicycle; yes, that's where I got a 14 mm wrench something like 30 years ago for my GWI.  And I just bought another (off Amazon) for the MBF.  Curiously, my 925 has no flats machined on the arbor for a wrench.  You change the blade by putting block of wood between the blade and table, and that's in the Mr. Sawdust book, IIRC.  Works just fine.  

I'm going to put an Oshlun 8-1/2" 60 tooth blade on it.  60 tooth is what Mr. Sawdust recommends, and it works great on my 925.  FWIW, that Oshlun blade costs something like $40 and cuts every bit as well as a blade costing much more.  They are a true bargain, at least at size.  The only 9" blade I've found for those saws is from Forrest and the price is far more than I'm willing to pay.  

John

[fredhargis]

John, i think of you look at the end of the arbor on the 925 you'll find it's machined to tale an allen wrench. Mine was, as is my current 1030K.

[pprobus]

John, i think of you look at the end of the arbor on the 925 you'll find it's machined to tale an allen wrench. Mine was, as is my current 1030K.

I wondered about this after reading his response. My 7790 has this, too.

[pprobus]

Parks bicycle; yes, that's where I got a 14 mm wrench something like 30 years ago for my GWI.  And I just bought another (off Amazon) for the MBF.  Curiously, my 925 has no flats machined on the arbor for a wrench.  You change the blade by putting block of wood between the blade and table, and that's in the Mr. Sawdust book, IIRC.  Works just fine.  

I'm going to put an Oshlun 8-1/2" 60 tooth blade on it.  60 tooth is what Mr. Sawdust recommends, and it works great on my 925.  FWIW, that Oshlun blade costs something like $40 and cuts every bit as well as a blade costing much more.  They are a true bargain, at least at size.  The only 9" blade I've found for those saws is from Forrest and the price is far more than I'm willing to pay.  

John

(Insert Thumbs Up emoji here).

For my MBF, I'm using the 8" LU83 blade. The 7790, I have the closest equivalent to the 10" LU83 Freud and the closest to the recommended 10" Forrest WWI blades that CMT makes, but the Forrest blade equivalent is full kerf (all other specs are the same). So far, the 7790 is OK with it. I got both blades when Woodcraft had black friday deals on both (back to back years) and have been holding on to them for a few years until I got the 7790 back together and up and running.

[jteneyck]

John, i think of you look at the end of the arbor on the 925 you'll find it's machined to tale an allen wrench. Mine was, as is my current 1030K.

Good grief, Fred, you are absolutely right.  I suspect I knew that when I first got the saw, but since forgot.  At least that's my story.  The good news is the piece of wood to jamb the blade works just fine, too.  

John

[Tapper]

Discovered on my GA today, the "mysterious" Allen wrench hole in the end of my arbor. Also discovered that if you don't put a wrench in that hole and hold it fast, even with a block of wood under the blade, the arbor will turn when tightening the arbor nut. Who knew?

Doug

[fredhargis]

I think (but do not know fir sure) that convention (the Allen wrench thing) was introduced with the square arm design (925, 103K, and newer) saws. There must have been a reason to eliminate the wrnch flats on the arbor though I have no idea what it might have been.

[jteneyck]

Discovered on my GA today, the "mysterious" Allen wrench hole in the end of my arbor. Also discovered that if you don't put a wrench in that hole and hold it fast, even with a block of wood under the blade, the arbor will turn when tightening the arbor nut. Who knew?

Doug

Put the block on the back side when tightening.  Not under the blade, but where the blade and table meet, as if the saw were about to cut it.  It works on my 925.  Of course, the hex wrench is a sure bet.  

John

[Tapper]

Put the block on the back side when tightening.  Not under the blade, but where the blade and table meet, as if the saw were about to cut it.  It works on my 925.  Of course, the hex wrench is a sure bet.  

John

Yep, did that. Arbor still spins.

Doug