Domino Mortise is too narrow

[iamnothim]

Your Feedback will be appreciated.

This is an update from my "Zero Response" thread and it now deals with the actual problem I am experiencing with my DF500.  The mortises that the machine bores are too narrow for a stock domino.  As in a lot too narrow.  I have to trim the dominos with a block plane for it to fit in the mortise  (Without significant hammering).  As, such,I sent my machine in for repair.  I got it back after a couple weeks.  The problem is still there.  They provided a list of parts they replaced but there wasn't a write up of what they did or why my machine does what it does. I called service and Bret couldn't provide much info.  He thought it might be the bit but it happens on all bits.  I mostly use 5mm and it seems to be more sensitive.  I have a second 5mm bit and it does the same thing.

It's been doing this since I purchased the machine two years ago.  I've been putting up with it thinking it might be n normal.  Now I'm building quite a few cabinets and I am tired of shaving every domino.  This can't be right.....and at some point I am sure to slip and plane my finger.

To demonstrate the problem I made a video.  I'd like to see if this is normal.  Keep in mind I am using very soft pine in the video.  There is no way to get a "stock" domino into Oak or plywood without causing a lot of damage. 
Many thanks
Luke
http://vimeo.com/223649741

 

[bdiemer]

I live on the great south bay ,Long Island. All my dominoes are swollen and require minor adaption,with sandpaper. Try a domino right out of the plastic.

 

[iamnothim]

I'm in dry Southern California.  The dominos are very new.
Also, I'd be sanding a long time before they would fit.  Hence the block plane

 

[Distinctive Interiors]

All the domino slots that I have cut in solid timber with my DF500 are a tight fit in their respective holes. I certainly can't push them in or pull them out of their holes without the use of pliers. MDF or particle boards are a bit softer so are less of a tight fit.

I keep all my dominos in a Systainer with a couple of little bags of Silica. This keeps the moisture content down.

I mainly use the 4mm,5mm and 6mm cutters/dominos so I can't vouch for the 8mm or 10mm slots width.

Have you tried a fresh batch of dominos, just to be certain that its not your own dominos themselves that are causing the issue..?

 

[iamnothim]

Thanks for the post.

I too mostly use 5mm.  They are very fresh. They don't hang around long and this has been going on for 2 years.

 

[drax]

Iamnothim, you can determine for definite if it's your machine or the dominos by measuring accurately the width of the slot with callipers or a rule etc then compare with another fog 500 owner the width. I won't have access to mine until next week unfortunately so can't help there.

 

[iamnothim]

The mortises are 17.25mm wide
The Dominos are 18.8mm wide

 

[justaguy]

I think I see the holder for the bit assortment on your bench. Have you tried the other size bits and is the problem consistent with each size?

Sorry I left the edit window open for a while. I now see from later responses that you have tried the other bits.

 

[iamnothim]

It's all good!
Thanks

 

[RobNJ]

Is the domino width including the ridges on the sides?  I always wind up planing or sanding the ridges away -- though never have have to go more than the small ridge.  Also, it's my standard procedure to throw the Dominos in the microwave for 25 seconds.  Even in the bone dry winter (my shop is in a heated basement) a significant amount of water is left in the bowl post microwave.  The dominos fit much more easily post a quick zap.

 

[ear3]

You got me curious so I plunged some 5mm mortises and measure between 18.4-18.5mm on the mortises.  Yours seems to be 1 mm too narrow.

The mortises are 17.25mm wide
The Dominos are 18.8mm wide

 

[iamnothim]

You got me curious so I plunged some 5mm mortises and measure between 18.4-18.5mm on the mortises.  Yours seems to be 1 mm too narrow.

The mortises are 17.25mm wide
The Dominos are 18.8mm wide

Great information !
Thanks

I also tried two different 5mm bits

 

[hopper]

I know this is a band-aid fix but try putting a small shim type washer between the bit and bit holder where it threads on. this would make the bit slightly longer consequently making the mortise wider

 

[iamnothim]

The tool is at UPS on its way to Indiana

 

[ear3]

That's the right move.  I would even flag [member=57769]TylerC[/member] and have him give service a heads up to let them know this is the second time your unit is going in for the same problem, and that you have conferred with other Domino users to establish that it's a genuine issue, and not simply your imagining or misuse.

The tool is at UPS on its way to Indiana

 

[TylerC]

That's the right move.  I would even flag [member=57769]TylerC[/member] and have him give service a heads up to let them know this is the second time your unit is going in for the same problem, and that you have conferred with other Domino users to establish that it's a genuine issue, and not simply your imagining or misuse.

The tool is at UPS on its way to Indiana

Yes. I'll send this thread over to the service team. I'll send it to a few other folks internally. Honestly, I'm a bit beyond my depth on this one.

 

[daveg]

I've always had this problem (since my DF500 was new). The domino size and season don't seem to make much difference. I assumed it was by Festool's design to have a very tight fit for alignment purposes. However, I find it very inconvenient for doing dry fit tests before I glue up. In those situations, I use the block plane on the edges like you or I put the dominos in a drying box (foam insulation with a light bulb for heat).

 

[iamnothim]

I've always had this problem (since my DF500 was new). The domino size and season don't seem to make much difference. I assumed it was by Festool's design to have a very tight fit for alignment purposes. However, I find it very inconvenient for doing dry fit tests before I glue up. In those situations, I use the block plane on the edges like you or I put the dominos in a drying box (foam insulation with a light bulb for heat).

Dave,
It's reassuring that someone else has experienced this problem.  It's very annoying and time consuming. I don't think a production  shop would put up with this.  We shouldn't have to go through these steps either.  It's very dangerous trimming a tiny domino in your fingers on a block plane, yet I've shaved hundreds without giving blood.

My video is with pine.  I should have used oak.  I don't think I could insert a stock domino using a hammer.  I haven't tried for years, I've just plane the dominos as a procedure.  I'll be sure to post the verdict.

Thanks for posting,

Luke

 

[Distinctive Interiors]

I measured my 5mm dominos today. Width was between 19.05mm to 19.12mm. I measured about 20 odd just to get an average size. All measurements were taken with a digital Vernier gauge.
I didn't have time to do a trial slot in some scrap...been busy with designs all day!

 

[iamnothim]

[member=14860]Distinctive Interiors[/member]

That's very wide.
Thanks for thinking about me.