Difficulty in raising the blade

[wizeguy4]

Hello all,

I have a BT3000 and up until just recently, it has worked out great, but recently, I have been having a very difficult time raising the blade. Lowering it is still simple but raising it get to the point of needing 2 hands to turn the crank. Anyone have any ideas? Sounds like a lift assembly issue but not sure. I just want to get this corrected.

Thanks

[Sawatzky]

If it is a BT3000, you might want to check the shims on the motor mount. They have been known to slip and/or fall out. If they have fallen out, there are plenty of articles here that explain how to fix that. You also may want to make sure the lift mechanism is well lubed with a silicon free lubricant.

[leehljp]

1. It is possible that the riving knife is rubbing fairly tight against the back of the throat plate. This happens sometimes.

2. The shims on a 3000 slip out, bend or break; Replace.

3. Sometimes the threads in the lift strip out. Helicoil inserts are the only answer other than buying a new housing or from someone parting out a BT.

[mschrank]

Not saying for sure that it's the shims, but sounds like it. Here's a couple of links to help:

http://www.bt3central.com/showthread.php?t=27266&highlight=shim

http://www2.gol.com/users/nhavens/htmlfile/shims1-e.html

[steve_b]

Other than what everyone else has said - take the covers off and look at the the bevel gear and shafts that raise the blade - the vertical shaft has a thrust washer at the bottom that takes all the vertical load - make sure it is lubricated also the threads are clean.

Let us know what you find..


S

[wizeguy4]

oh boy - well I might as well get this out there - I have owned this saw since new 6 yers ago and I can tell you the most maintence it has gotten was unpacking and putting it together. So I am sure I am going to find many things need some cleaning.

I know it is not the riving knife cause I dont have one. Well I do but it is still in the box (at least it was).

Where do I buy new shims? cause even if this is not the problem, I think I will replace them anyway. I also have gone through the article section here for maintenence and I might as well do a bunch of other things while I have it all open.

[mschrank]

Where do I buy new shims? cause even if this is not the problem, I think I will replace them anyway. I also have gone through the article section here for maintenence and I might as well do a bunch of other things while I have it all open.

http://www.m-and-d.com/ryobi_tools.html

[kmk]

1. It is possible that the riving knife is rubbing fairly tight against the back of the throat plate. This happens sometimes.

This happens to me all the time and tired of it. If I didn't notice it, they simply lodge themselves into plastic throat plate. I hold them and then raise the blades.

[LCHIEN]

From my BT3 FAQ:

I'm having trouble with raising the blade...
I’m hearing a clicking noise when I raise the blade
What is this shim problem I’ve heard so much about?
Don’t force it! In order from least to worst possible problem:

The clicking noise is normal. This is the spring as it rotates on the keeper pin. Behind the adjustment handle. You can bend in the ends of the wire with a needle nose pliers so it will not catch on the edge of the spring.

It’s very frequently the case that in reattaching the riving knife/splitter assembly, the two bolts have enough play that the riving knife leans backwards. When the blade is lowered, at some point the back of the riving knife touches the edge of the opening and drags, making it hard to lower the blade. Usually no damage done except to pride.

Your saw needs cleaning; internally the dust has gotten to the point where the gears and elevation mechanism are jammed. Also lubricate the vertical screw thread shaft along its length with a dry-lube (so it won't attract and hold sawdust), making sure to lube the point where it engages the motor assembly.

Occasionally you will have the dreaded shim problem (a BT3000/Sears 22811 quirk, this has been fixed in BT3100s). The shims are thin metal plates that ride between the motor holder and the saw frame when traveling vertically. They are normally held in place with the motor housing but can be deformed and fall out when the lubrication is not adequate. If you find some small metal plate below your saw body then the shim(s) have likely fallen out and will need to be replaced as they are the anti-wear mechanism. Vertical movement will become difficult. The shims are inexpensive but the labor can be a few hours. Keep your saw lubricated in this area with a dry lubricant. Johnson’s paste wax is good for this. A February, 2005 survey on BT3Central indicated that 70% of BT3 owners never had the problem but that 30% had some problem with shims.

The BT3100 does not have the shim problem because the shims, though used, have a mechanical retainer. You can convert the BT3000 to the BT3100 shim system. The conversion is simple if you will have the saw apart to replace the belts and the cost is negligible
Parts List:
#969600001 Flat shim [BT3000/BT3100}$.90 ea, 2 needed
#0181010314 Spring shim {BT3100} $.86 ea, 2 needed
#0181010110 Guide holder {BT3100} $15.07 ea, 1 needed
#662329001 Dvive belt {BT3000/BT3100} $13.49 ea, 2 needed
The parts are available from:
www.ordertree.com
www.billious.com


Sometimes the threaded elevation rod engages a nut and the nut is worn/stripped. You will need to enlarge the hole and thread a new helicoil (a stainless steel threaded insert) into the hole to repair the thread. See these elevation rebuild instructions by JohnG.
[posted by "Knuckles" Brian] I went the HeliCoil route. Thanks to Ed's instructions in the Article section, it wasn't too difficult. It's not something I'd want to do every day. I searched about a dozen auto parts, hardware, and machine shops in this area, and I had no luck finding the 9/16"-12 Helicoil (or clone) kit. I ended up ordering one from a website called Cartools.com. It cost something like $50, shipping included. Wouldn't you know, though, after I bought it I stopped in a local discount tool place that I hadn't noticed previously; they had a clone (Permacoil) kit for $15.
The next problem was finding a 19/32" drill bit to drill out the lug that the threaded rod goes through. …
Probably the most tedious (and potentially disastrous) step of the repair was drilling out the hole prior to tapping it. I figured that I only had one shot to drill the hole on the same axis, and I wouldn't know how well I did until "the reckoning" of trying to put it together. I used a 1/2" drill bit to help get the bit centered, and find the axis. I didn't measure the angle, but it wasn't exactly 90º to the table. I had to shim it with some laminated air and a few mosquito wings.
Once I got the hole drilled and tapped, the insert went in nice and easy, and I epoxied it in place. I made sure to keep screwing the insert tool in and out so that any epoxy that squeezed into the inside threads was "threaded" in.
I learned something during assembly that's important to the instructions. Install the threaded rod and bevel gears before tightening the screws that attach the motor housing and the guide holder. …
So, long story longer. . . . I was successful at installing the Helicoil insert. I've noticed that there is considerably less "play" in the mechanism, even less than when it was brand new. It's firmer and requires more effort to turn the handle, but not "won't raise/lower right" firm. It still feels like the Play-Skool handle is going to snap. Even though Ryobi Tech Support knows about the issue with the "soft" threads, I'm still going to send a note expressing my opinion that they should "toughen" that part up.

Factoid: the blade raising mechanism has a 12 TPI thread – it takes 12 turns to raise the blade one inch, or .0833" per crank turn. On my saw you can crank it exactly 12 turns one way then exactly 12 turns back and it will come back to about +/-.005" of where you started.

[wizeguy4]

ok so I decided to start taking things apart last night. and I got out my trusty camera. I cleaned out my table saw before taking these pics to avoid embarrassement

this is all that was in there

only the rear shims were present, the front shims (that from what I have read are a right angled peice of SS, were not there at all.

Here are teh shims after removal. They are actually in good shape and are not flattened at the top and bottom at all. However, for such a small cost and I have to wait to buy the fronts ones anyway, I am goign to order both the fron and a new rear set


I take it this is a shot of the nut that sometimes needs to be drilled out and then insert a helicoil? Mine is in decent shape still and I swung the motor out and placed my hand under it for support and turned the up and down crank and the motor went up and down with very little effor ton the crank, like is should be.


now here is another question about the picture below - there was a thick metal washer for lack of kowing what else to call it that was just sitting on the arbor. It was 2 peices a thicker and thinner one. Is this the way this should be or is it supposed to be one peice that has broken? And what is it called so if I need to order it I dont sound dumb 2 times These peices are also located in picture number 2 above. They are right above the shims.


So all in all, it seems my problem is due to the front shims not being present. a nice easy fix

[leehljp]

The two pieces on the arbor that you are asking about - they are spacers. You take them off in increments when you use dado blades of varying thickness. You don't need to replace them other than if you just want an extra set - in case you lose them.

[wizeguy4]

well , that certainly makes sense. I guess I have not thought that cause I use my table saw for just cutting up wood or to square up multiple peices. I have just gotten used to using my router for making dadoes.

But I have ordered the shims and I needed to have a minimum order or else have to pay 4 bucks just for having a small order so I ordered the plastic endcaps for the rails and I was still short a few bucks and so I figured, what the heck, might as well just get new brushes while I am in there. I do nto kwo the conditions, but new brushes cant hurt and rather than feel like I am just pissing away money on a short order charge, might as well get soemthing. My belts look fine and I really did not want to spend another 40 bucks for them

[mschrank]

No front shims at all..? Yes I suppose that would make raising the blade tricky. Glad you found the problem wizeguy

This happens to me all the time and tired of it. If I didn't notice it, they simply lodge themselves into plastic throat plate. I hold them and then raise the blades.

I think you mean the pawls, not the riving knife? I had the same problem...some here have recommended filing the points down a bit, but I'm too lazy for that. I simply covered them with electrical tape. It keeps 'em from digging into the throat plate when lowering the blade and scratching your stock when ripping, but they still bite in the case of kick back (DAMHIKT).

[wizeguy4]

that is right no front shims. And now that I think of it, this problem has been going on since I moved into this house about 17 months ago. I am thinking somehow in the trip of in carrying the saw downstairs, that something must have went a bit wrong and somehow they came out.

But at least I got a new hang on the net, I suppose

[wizeguy4]

UPDATE:

I receive my pack of shims yesterday. So I replace the shims yesterday and also the motor brushes and lubed everything up (including that threaded rod that makes the motor go up and down and I am happy to say I practically have a brand new saw again. The raise and lower movement is so fluid and smooth now. It works great! I had to go look around for scrap wood to chop up