Saw Base "Flattness" and Kickback

[Sourwould]

First a little background.

In August I bought a second hand TS55 on ebay that ended up having a bent base and was missing some parts. While waiting for the return on that to go through, I bought a Makita track saw. I ended up getting a straight refund on the Festool, so I decided to keep the Makita and try and get some stuff done while waiting for the parts for the Festool to arrive.

I finally got some time to build something (for me) today and broke out the Makita. First plunge and the saw kicks back hard and cuts into the track. The saw kicks back on nearly every cut I try and make. Sketchy!

I'm not a homegamer or a novice. I work as a carpenter and use a skilsaw 5 days a week or more. Many of the cuts I make are less than ideal, made with a dull blade or in awkward positions on ladders. I haven't had kickback I couldn't control since my first year on the job. So I feel pretty comfortable ruling out my technique. Granted, this is my first track saw. My boss has the Makita and I've used it trimming doors or sopping wet PT decking or even in Pecan without much fuss.

What I noticed about the Makita I have is that the saw rocks corner to corner on the track about an 1/8", like the base is twisted. I feel pretty good ruling out the track as the case of the problem because there's so much rock. I feel like that amount of twist in the track would be obvious if I sighted it. I have not tried to rig up twist sticks on the base to check it, but did try in on a freshly jointed piece of wood and it rocked like on the track. Is this the cause of my kickback woes?

So I got curious and decided to check the replacement base I ordered for the TS55 on the track and see if it sat well. It rocks too, About a 1/16" and on opposite corners as the Makita. Should I worry about this?

Frustrating!

 

[deepcreek]

If they both rock, I would check the rail for flatness.  Make sure it's not twisted.  That could be your problem.

 

[peter halle]

If you are used to using a Skilsaw and making plunges with that and then trying to make plunges with the track saw the same way you probably will have kickback.  If you are trying to make a plunge cut with the Festools for instance there is a plastic anti kickback block that you install on the rail.  If you are cutting material down to size it is best to have the saw fully plunged before the blade enters the work piece.

I hope you don't take this the wrong way.  The track saws are just different.

Peter

 

[Sourwould]

Peter, no offense taken!

[unsure] I believe this may have been some user error....

I'm really used to doing things a certain way and didn't really bother trying to find out if I needed to do things differently with a new tool. Its weird that I've never had any kickback from my boss's makita.

Would the saw be less inclined to kick back with a courser blade (such as a 28 tooth "universal")?

I'm still less than happy with the wobbly bases. I checked the Makita with a straight edge and it's got a big high spot on the bottom of the base. So it's getting chucked back to the retailer. Most of my tools are older Makitas. I've been really disappointed with the QC on the last few new Makita tools I've bought.

Oddly, the Festool replacement base only wobbles on the lower half of my rail. Hard to say what the issue is, base or rail. The rail has so many different planes on it that it seems impossible to check it across its width or for twist. I would think that the saw would press the rail more or less flat as it traveled along it.

 

[ILT]

Just for giggles and grins, take a look at this short utube video (3 minutes 47 seconds). Yes, it's about the "twisted" Bosch track saw base, but there may be a solution for you too. 

 

[RKA]

If you think about where you're pivoting the saw in a plunge, the direction of the blade travel and where the meat of the cutting is happening you'll realize why the track saws are different when you plunge. 

With a traditional sidewinder you pivot in the front of the base plate.  As you feed the saw down, you are doing most of your cutting on the back side of the blade which is spinning down into the material.  You hand is directly above applying downward pressure to complete the plunge.  It's a reasonably controlled cut. 

With a tracksaw, the pivot is in the back of the base plate.  You lean the saw head forward, you are doing most of your cutting on the front side of the blade which is spinning up from below.  As the blade grabs it wants to pull the head down (while you are also applying downward pressure).  The only thing counteracting this is the force of the spring on the saw head, which is negligible.  Similar to a climb cut, you lose control.  So the saw head gets sucked down instantly and pushed back as the head travel bottoms out.  While it's a good substitute for your morning coffee, I don't recommend it.

As to your baseplate issue, I'm not familiar with the Makita, but I would hazard a guess that the kickbacks may have tweaked the base plate?  Try a new one and check it for flat on a truly flat surface before using it.  Then put on the rail and check that.  Don't plunge unless you have the plastic stop block Peter talked about.  Drop the saw head fully while on the track, then feed the blade into the wood.

I doubt the rail is your issue, unless it's visibly bent, which you would see sighting down the rail.  Even if it had a little twist (so little you could not see it by eye), it should lie flat on a piece of plywood. 

Checking your bevel mechanism as suggested above is a good one.  It's possible something has bound up and created some tension (or a good knock during shipping).  Loosen up the bevel knobs, move the saw out to 45 and back just to check for anything obviously causing tension, lock it back at 90 and check the base plate again.

 

[Sanderxpander]

With a track saw plunge, the bottom part of the blade, where the teeth are moving forwards, are what is hitting the wood first. Unless you move the saw forward while plunging, which you should obviously never do.

Holding the saw still while plunging, I've never once had the feeling it was "pulling down".

 

[RKA]

Correct, if you use that stop block Peter recommended with the tracksaw, it will allow for a controlled plunge.

 

[Sourwould]

I've ordered a couple of the stop blocks in case I need to do any plunge cutting. I plan to use my little Makita router on the track as well, and I figure they'll come in handy for that anyway. Now I wish I'd bought the 75" track for crosscutting plywood. I think it'd be nice to have that extra track to start and stop the saw on. When I was framing houses full time, I really got into the habit of starting all my cuts with a half plunge (not sure if this makes sense). Easy way to do really fast square cuts for me. I was probably setting my saw on the track too far forward without thinking.

As for the Makita base plate, I combed over the bottom with a straight edge. It's not so much a twist as a very high spot in the middle of the base on the motor side. The effect is the same, a rocking saw. The paint on the high spot is even dulled from running across the track.

I've finally got all the parts to set up my TS55, so that's the route I'm going to go. Festool is expensive but at least they don't expect me to act as their QC. My boss's Makita saw is great, but he also got a bowed track with it. It's too hit and miss, especially when there's no brick and mortar in my town to bring the stuff back to.