Advice needed on trimming benchtop edges

[Jeff Dege]

I'm just getting started in woodworking, and I'm building a workbench. I'm constructing the top out of two layers of 3/4" MDF and a 1-1/2" edge-glued oak countertop from Ikea. The top was a couple of inches wider than I needed, so I'm using some strips sawed from it to edge the MDF. The two layers of MDF are glued, and the oak edging strips are glued to the MDF. I plan on screwing the countertop to the MDF without glue.

Both the completed MDF panels and the countertop are a bit oversize. I left 1/8" to 1/4" on each side. I need to take off this last bit to match the top to the base, and to match the two parts of the top to each other. The question is, how?

I can see four possibilities:

1. Screw the two layers together and run them through a jointer.

2. Screw the two layers together and go at them with a belt sander.

3. Screw the two layers together and and go at them with a hand plane.

4. Use 1-1/2" straight bit in a router and a straight edge to trim the MDF layer, then screw the layers together and use a 1-1/2" flush-trim bit to trim the countertop to match.

Problems:

1. I don't have a jointer, and even if I did, I wouldn't have a jointer that came close to having a bed that could handle this.

2. I do have a belt sander, and a random orbit palm sander, and I'm pretty sure I could make this work, if I don't rush things and use too aggressive a grit.

3. The only plane I have right now is a block plane, and I'd need a jack plane, at least. I could probably finish it off with the sanding blocks and/or the random orbit sander.

4. The only 1-1/2" router bits I've seen used a 1/2" chuck, and the only router I have has a 1/4" chuck.

Questions:

Will option #3 or #4 do a better job than option #2?

I'm sure that option #4 would be fastest, but I'm not sure I can justify the expense of buying another router when the router I have has been able to do all I've asked for it up until now. OTOH, my current router doesn't look all that well suited for use in a router table.

At this point, I'm trying to decide whether to buy a jack plane, whether to buy one of those new routers with the top-side height adjustment, and 1/2" collet capability, or whether to just bite the bullet, pull out my goggles, ear plugs, and dust mask, and finish it off with the belt sander.

Suggestions?

[John Morrison60]

Jeff

If you are taking the time now to create such a sturdy bench, I would suggest that you will use it increasingly as time goes on.

The best tool to do the edge cleanup is a router.
Use a straight bit with a bearing.
It will do it far better than any of the other methods you listed.

You will find yourself in need of a router with a 1/2 inch collet.
I suggest that now is the time to get one.
WoodCraft has the 2.25 hp Freud router on sale for $100.
That would make short work of this task, and serve you well in the future.

Good Luck
John

[Jeff Dege]

You will find yourself in need of a router with a 1/2 inch collet.
I suggest that now is the time to get one.
WoodCraft has the 2.25 hp Freud router on sale for $100.
That would make short work of this task, and serve you well in the future.
:mad:That's exactly the kind of router I was considering if I were to buy a second router. And it's on sale.

And I was trying to convince myself that I didn't need to spend the money ... :(

[Neil Bosdet]

Jeff

If you are taking the time now to create such a sturdy bench, I would suggest that you will use it increasingly as time goes on.

The best tool to do the edge cleanup is a router.
Use a straight bit with a bearing.
It will do it far better than any of the other methods you listed.

You will find yourself in need of a router with a 1/2 inch collet.
I suggest that now is the time to get one.
WoodCraft has the 2.25 hp Freud router on sale for $100.
That would make short work of this task, and serve you well in the future.

Good Luck
John

I agree with John. It's what came to mind for your situation.

[Jeff Dege]

The best tool to do the edge cleanup is a router.
Use a straight bit with a bearing.
Any ideas on how to do this?

The longest cutting length I can find in a router bit is 2", and that won't handle the two layers together. Right now, I'm thinking using a top-bearing straight bit with a straight edge, to cleanup one layer, then screw the two layers together and then use a bottom-bearing straight edge to match the two layers.

Is there a simpler way to do this?

[Greg Hines, MD]

Generally, these kinds of problems are best solved with a pair of bits, a flush trim bit and a pattern bit. You will also need a straight edge to guide the router, the bit, or both. A piece of 3/4" MDF or plywood would be fine, or a straight 2x4. Use the Pattern bit first, and cut the top flush with your straight edge as deep as you can.

Then you can flip the top, and use your flush trim bit to clean up the other side, now that you have a smooth reference from the other bit.

Depending on your budget, a spiral bit will do a better job, though a straight bit will do fine too. Take light passes.

I would definitely upgrade your router. Keep it for quick and dirty work, but you will need a much larger router if you ever intend to use it in a table.

Doc

[Jeff Dege]

Use the Pattern bit first, and cut the top flush with your straight edge as deep as you can.

Then you can flip the top, and use your flush trim bit to clean up the other side, now that you have a smooth reference from the other bit.
If I had a 3" thick piece to work, I can see how that might be the only solution. But since I have two 1-1/2" pieces, might it be easier to do the first cut on one layer, prior to joining them? The second cut would have to be done after joining them, of course, but combined the two layers weigh about 150 pounds, and flipping them more times than is necessary is something I'd like to avoid.

Another thing I'm considering. A pattern bit has a bearing at the top that rides along the pattern - in this case a straight edge. A flush trim bit has a bearing at the bottom that rides against the side of the work piece. In my situation, is there any reason why I could not clamp the straight edge to the bottom of one of my layers, and to use the flush trim bit for both passes? This wouldn't be possible on a 3" thick piece, but on a 1-1/2" thick piece it seems like it would work.

[Greg Hines, MD]

If I had a 3" thick piece to work, I can see how that might be the only solution. But since I have two 1-1/2" pieces, might it be easier to do the first cut on one layer, prior to joining them? The second cut would have to be done after joining them, of course, but combined the two layers weigh about 150 pounds, and flipping them more times than is necessary is something I'd like to avoid.

Another thing I'm considering. A pattern bit has a bearing at the top that rides along the pattern - in this case a straight edge. A flush trim bit has a bearing at the bottom that rides against the side of the work piece. In my situation, is there any reason why I could not clamp the straight edge to the bottom of one of my layers, and to use the flush trim bit for both passes? This wouldn't be possible on a 3" thick piece, but on a 1-1/2" thick piece it seems like it would work.

Well, doing that would make them both straight, but not make them identical to each other. If you goal is to make a monolithic piece, it would be best to true them at the same time.

If it is the flipping part that you are concerned about, true up the bottom two layers first, with your straight edge. Then, after you have screwed them together, true up the top with a flush trim bit from the top surface.

Doc

[chris beserra]

You could clamp a straight edge on the MDF layers, cut it with the circular saw, attach the oak top and do the same, then sand out any blade marks.

Quicker and cheaper.

[Jeff Dege]

Well, doing that would make them both straight, but not make them identical to each other. If you goal is to make a monolithic piece, it would be best to true them at the same time.
I must not be explaining myself well.

The suggestion was to use join the two layers, then to a top-bearing straight bit with a straight edge to straighten one layer, then to flip it and use a bottom-bearing straight edge to match the other layer to the first.

My proposed alternative is to use a bottom-bearing straight bit with a straight edge to straighten one layer, prior to joining the two, then to join the two and to use a bottom-bearing straight bit to match the other layer to the first.

The final pass would be after joining the two layers, and would - from what I can see - make them identical to each other.

[Greg Hines, MD]

I must not be explaining myself well.

The suggestion was to use join the two layers, then to a top-bearing straight bit with a straight edge to straighten one layer, then to flip it and use a bottom-bearing straight edge to match the other layer to the first.

My proposed alternative is to use a bottom-bearing straight bit with a straight edge to straighten one layer, prior to joining the two, then to join the two and to use a bottom-bearing straight bit to match the other layer to the first.

The final pass would be after joining the two layers, and would - from what I can see - make them identical to each other.

Yes, that is how I would do it. The placement of the straight edge is dependent on your bit. I have a pattern bit that I like to use for this, and it has the bearing on the top, so that is where I would put my straight edge.

Doc

[Chris Padilla]

I would go the circular saw route myself. I would cut it just a hair proud and handplane it or handsand it the rest of the way or use the router.

[Jeff Dege]

I would go the circular saw route myself. I would cut it just a hair proud and handplane it or handsand it the rest of the way or use the router.
Plane, sand, or use the router - yep. Those were the three options I started with.

Anyone know where I can get one of those Doctor Evil laser beams? That might work :D