domino plywood problems

[blanning]

I'm sure this has been discussed before.  I searched the forum, but didn't find an exact match.  So here goes.

I tried out my domino for the first time tonight.  I tried out cutting three M&T joints on two 3/4" scrap pieces of baltic birch plywood.  Immediately, I noticed problems with chatter.  It was so bad that both the work piece and the domino danced around.  This made one of the dominos not line up since it slipped while making the cut.

I'm sure this won't be a problem with hardwoods because they have uniform density throughout the cut.  So I'm not surprised that plywood is a little more problematic.  I just didn't expect this much trouble with plywood.

I had been holding down both the work piece and the domino with my hands.  Clamping down the work piece will probably improve the situation.  But I think the forces involved would likely make the wood move anyway.  And regardless, the domino machine will still be free to slip from side to side.

Some of the cuts looks good, but others looked downright terrible.  I think by setting the domino to make mortises wider than the tenons, it could help the situation.  But what I'd really like is a smoother cut that's easier to make.

Does anyone have a technique for this that could make the mortises easier to cut?  I'm planning to put some cabinets together with this.  And I can't see how cutting mortises in the face of a board will be really possible like this.

I'm using the bit that came with it at the moment.  But I have other sizes.

brian

 

[MattrYYC]

I don't think you should be having concerns about the ability of the domino to work on ply. I've only had mine for a few months but have built boxes out of 5/8 and 3/4 along with drawers out of 1/2 without any problems. I think clamping the workpiece down is 100% essential, I don't know how you could operate the domino while holding the workpiece. I usually have my left hand on the front handle, and use my right hand to do the plunge while I slowly count out a 'one, one thousand, two, one thousand' up to 4 in my head to make sure I don't do the plunge too fast in the material. I have noticed that sometimes the machine will not 'seat' flat and will drop if I don't take the time to ensure that the fence is properly flat, I eventually found that didn't happen the more I've used it, but sometimes I will pull it back and re-press it against the material before I start my plunge in the material.

You are using dust extraction I assume?

 

[NiteWalkerGR]

Use dust collection of you aren't.
I've had no problems with using it with any kind of plywood, baltic birch included,  or hardwoods including purpleheart. Clamping the workpiece down is a necessity. I use one of kreg's automaxx bench klamps holding it down. Works great.

 

[shed9]

I wouldn't worry, what you want to do is achievable -  just practise some more.

As others have said, clamping, plunge speed and extraction are key. Also what Domino is it? I found I had chatter with my first use with the 500 however the 700 was spot on from the get go.

 

[Birdhunter]

The physics of the Domino's cutting action, side to side, mandates strongly anchoring the work piece. I use strong downward pressure on the fence handle and a little pressure on the barrel. This is especially true when cutting into end grain. I have used my Dominos to join Baltic birch often with no problems. Shouldn't be a problem with the right technique.

The Seneca accessories, Domiplate or Domishim, really help with 3/4" and 1/2" plywood.

 

[wow]

Seneca Wood working links for those who might not know about them:

Domiplate:

http://www.senecawoodworking.com/products/domiplate-for-1-2-and-3-4-ply

Domishims:

http://www.senecawoodworking.com/products/domi-shims-for-domino-xl-df-700

 

[NiteWalkerGR]

+1 on the domiplate.
It's a great accessory.

And about the kreg automaxx bench klamps, I drilled 3/8" holes in my bench top  on a 4" grid and use a woodpecker multi knob and hex bolt to secure the clamp in place. The same can be done with an mft. I got the idea from eric's video on the automaxx clamps.

 

[gtriderr]

I would clamp down your workpiece and make sure you are at full speed before starting to cut mortice and hold speed steady until you have completed cutting.

I have used dominos in plywood and hardly ever use that wider settings.  

 

[Erich]

I absolutely agree with these guys.  Your workpiece needs to be clamped down.  The Domino 500 is definitely a two handed tool, one up forward on the fence handle and the second at the rear of the handle at the plug it connection.

I was ready to get rid of my Domino 500 because of alignment issues.  I called Festool USA for help.  The application specialist for the domino called me back and spent the better part of an hour with me on the phone helping me to understand what I was doing wrong.  Specifically how to best hold the tool and plunge smoothly and at the right rate of speed.

 

[blanning]

Thanks everyone for the responses. 

Executive summary:  I'm using a CT36.  I'll try to plunge slower.  I'll try clamping the workpiece down.

I should provide some background.  I left the US about 2.5 years ago.  Shortly before leaving I replaced some of my tools with other tools that I thought would be better suited to the environment here.  Part of that was switching many of my tools to festool.  Everything has been mostly in storage since I arrived.  I'm currently working on a mobile cabinet that goes under the table saw.  It's sort of a practice project before do a small kitchen cabinet project.

So today was my first use of the domino after buying it two and a half years ago.  [eek]  I had to go back and look at the internet to remember how to assemble the fence for the mft/3.  Some things are still hidden in a box somewhere, like the clamps.  But I was able to use the TS55 and mft/3 to cut down a huge sheet of baltic birch into perfect dimensions.  I've also been impressed with the dust deputy thingy on top of the vac.  So things are going well.

I believe I have a 500.  It's not the XL.

Do you guys make sort of a channel for the 500 to fit in?  Like maybe clamping boards on each side to stop the side to side movement?

How does the domiplate account for varying plywood thicknesses?

Any tricks to keep the domino aligned and planted when plunging into the middle of a large plywood piece?

Do you all trust only dominos for attaching shelves to vertical pieces?  Ordinarily, I'd use a dado for this.  but if the dominos are strong enough, they would be a great time saver.

brian

 

[Birdhunter]

Look at the 2 Dominos on the Festool web site to see which one you have if you are not sure.

Watch all of Halfinchshy's YouTube Domino videos before you turn on the machine again. He has a video on the Seneca  Domiplate and Domishim. He also has a video on cutting mortises in mid panel as you would for shelves.

You do not need any fixtures to use the Domino in any operation I've encountered. You do need to learn how to hold the machine. You do need to understand when to use the narrow setting and when to use the wide settings.

The Seneca accessories accommodate 1/2" and 3/4" plywood.

Again, watch the videos!

By the way, I hunt Perdiz in Uruguay and it is a beautiful country.

 

[roblg3]

just left training in indiana.  3/4 plywood needs to be off the table because your forward fence will not contact the face of the plywood . The face of the domino where the cutter plunges from is taller than the plywood.  measure it and see. 

 

[Roseland]

I'm a relative newcomer to the Domino - I only got mine in April - but for what it's worth here are my tips:

Clamp the workpiece securely, making sure the bottom of the Domino doesn't touch your bench.

Make sure the face of the domino (where the cutter emerges from) is snug up against the workpiece, press down firmly on the fence, start the Domino, let it get up to speed and plunge slowly.  I find it easiest to push it with my hip, whilst holding the back of the barrel.

Oh, and get a Domiplate.  It makes a world of difference to ease of use, accuracy and repeatability.  Use it whenever you can.

You'll soon wonder how you managed without the Domino.

Andrew

 

[hopper]

As mentioned once before,  make sure you are at full speed.

 

[Michael Kellough]

The difficulty you are experiencing in securing the Domino/work while mortising is not normal.
Even mortising Baltic birch, which is much tougher than the usual plywood, you should be able to hold both machine and work securely enough by hand. Unless the workpiece is very small.

Occasionally the carbide tip of the cutter breaks off the shaft on the 5mm cutter. (never heard of it happening on a larger cutter)
If your first mortises where good and subsequent mortises are bad I'd check the cutter.

 

[Peteman]

Make sure your bit is not broken.

 

[Sparktrician]

As others have mentioned, get your workpiece clamped down and off the edge of your workbench.  Listen to the motor as you plunge the Domino,  You should use a plunge rate that does not materially change the sound of the motor's speed.  Also, hold the Domino by the Plug-It connector rather than by the barrel of the motor.  Holding it further back allows you to get a straighter plunge into the material.  Take your time until you get the feel for it. 

 

[blanning]

Thanks for all the suggestions.  I'll try it tomorrow.

brian