Mft/3 Deep Cut Repair

[Curt Putnam]

Lost focus while cutting 6/4 material and slipped in some 3/4 ply.  Nicked the aluminum and did not go quite all the way through the table mdf.  I'm thinking liquid epoxy to start followed by epoxy putty.  Worried about how to get it down into the saw kerf.

What is the best way to repair?  How do you avoid doing it again?

Thanks for your help

 

[jeffinsgf]

Search the forum for the countless ways to make a new top. By the time you try to epoxy the thing back together, foul a couple of dog holes clean up the epoxy you got all over the shop and sand down the lump of epoxy to be flat with the table, you could have a new top cut and installed.

 

[Birdhunter]

I crammed two part wood filler into the kerf. Sanded it smooth after it set really hard. The wood filler has to be kneaded to get it mixed up before use. Good stuff.

 

[Knight Woodworks]

I cut through the top on my MFT the day I got it, many years ago. Left it as is, serves to remind me to check the depth of cut. Hasn't been a problem.

If you want to fix yours, I recommend cutting a strip of wood the thickness of the saw kerf. Glue it in place, plane or sand it flush.

Good luck,

John

 

[Michael Kellough]

I crammed two part wood filler into the kerf. Sanded it smooth after it set really hard. The wood filler has to be kneaded to get it mixed up before use. Good stuff.

That’s what I’d use. That’s what I used (in the color grey) when I cut a curving groove through a guide rail during an unplanned kickback.

 

[sancho57]

I use wood bondo

 

[SoonerFan]

Like [member=10147]jobsworth[/member] I used bondo.  It was easy, fast and has held well for a year or more.

I use wood bondo

 

[Cheese]

A 3rd vote for a wood filler strip. It provides positive structural reinforcement to the cut and the glue becomes a stronger bond than the wood. Thus all elements become one.

Unfortunately Bondo, while easy to use, provides little structural support. Think of what Bondo was initially meant to do...a 2-part catalytic plastic surfacing patch to be used in cars to repair dents. It wasn't meant to be used as a structural reinforcement material, simply as a bandage that would be covered with paint.

The caveat to this issue is if the saw cut is only 1/4” or less in depth, then I’d also go for the Bondo because structural fidelity hasn’t been compromised.

 

[Kanuka]

Mix CA glue into baby powder, smear it in, sand flush. Or just ignore it since that's the entire point of a sacrificial table top.

 

[Birdhunter]

When I used two-part wood filler, my cut was about 3/8" deep so the wood filler provided all the structural reinforcement I needed. It the cut had been deeper, I would have used the wood (probably hard maple) glued-in strip sanded flush. A shallow cut doesn't give a glued-in strip much anchorage.

The MFT tops tend to sag over time. It there is a meaningful gap (cut) in the top, I believe the sag tendency would be reinforced.

 

[Curt Putnam]

Thank you all.  inasmuch as the cut is ~ 3/4", I'm going to fill with some 1/8" ply I happen to have.

I wish to thank you all for the time and effort you put into your responses.

 

[Curt Putnam]

Didn't have any 1/8" ply, it was 6 mm BB.  Did not know if either my Grizzly bandsaw or I could do it, but the perfect slice off some poplar to fit the kerf in 2 tries.  It is glued in and the glue is drying - just need to plane it down.  Thanks again to all you folks who helped out.

 

[Bob D.]

This might be an excuse to install a sacrificial insert in your MFT top. Add a reinforcing strip to the underside of maybe a couple of aluminum angle, one supporting each side of the strip. It will impact clamping in that one narrow area, but is that really going to hurt you?

 

[Curt Putnam]

This might be an excuse to install a sacrificial insert in your MFT top. Add a reinforcing strip to the underside of maybe a couple of aluminum angle, one supporting each side of the strip. It will impact clamping in that one narrow area, but is that really going to hurt you?

Sounds like a good idea,  I'll have to think about it.  The whole table needs reinforcement.

 

[ILT]

I have the same problem.

This Peter Millard video might give you a little insight into installing a sacrificial strip. I think I'm going to give it a try on my carved up MFT.