Hole placement for MFT style tops

[dlu]

I'm planning to make some MFT style tops for some portable benches. My current plan is for the tops to be the full area of the benches (like the Ron Paulk benches) rather than inset (like a "real" MFT). I'd like to make a set of modular tops out of "super light" MDF so that bench units aren't too heavy and so they can be arrange either along the wall of my small (ish 20' by 20' shop) or grouped in the middle for a cutting/assembly table. The current question is how far in from the edge to place the first row of holes. i'm pondering:

• Is it useful to have a row of holes near the edge (say 32mm or 64mm in)? If they are that close a clamp would hit the structure of the table in the first row if you attempt to set the clamps square to the edge.
• If you do a row close to the edge, is the next row 96mm away or is the close to the edge row "extra?"

[*]At the ends should I attempt to maintain the 96mm grid across the modules (e.g. space the holes 48mm from the sides)?
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Any insight would be greatly appreciated.

 

[glenn storey]

Super light M.D.F.? Good luck with that.

 

[Stone Message]

Hi Douglas

I am in the process of making a set of videos about the Parf Guide System Mark 2 and am showing some ways to do holes at spacings other than the usual 96 mm. There are many advantages in playing around with this as long as accuracy can be maintained.

Should have something in a couple of weeks.

Peter

 

[dlu]

Super light M.D.F.? Good luck with that.

What problems do you anticipate?

 

[Roseland]

Regular MDF will, over time, sag.  AFAIK MFT tops from Festool are HDF, or from Axminster waterproof HDF (Valchromat).

If you want something lighter than HDF I’d use ply.  The surface won’t be as hard, unless you can use phenolic-faced.

Andrew

 

[glenn storey]

I anticipate it being heavy, since I don't think super light M.D.F. exists.

 

[dlu]

I anticipate it being heavy, since I don't think super light M.D.F. exists.

It's about 30% lighter than normal MDF - don't know if "super light" is really how I'd describe it, but that's what the manufacturer says... The tops will be about 25-30 pounds (12-15 kgs).

 

[glenn storey]

I'm not sure about 5/8" M.D.F., but i know that a 4' x 8' sheet of 3/4" weighs 97 lbs. If it was me, I'd use Extira, since it's waterproof, and since I work outside most of the spring, summer and fall.

 

[Stone Message]

Can you get Medite Moisture Resistant MDF in North America? It is a fantastic material as it is lighter than HDF but has hardened outer layers which make it ideal for bench tops. It machines well and the 19 mm thick version is my No. 1 choice for tops being made with the Parf Guide System.

In the UK it is not much more expensive than normal MDF and so one does not need to worry if you damage the top as you can soon make another.

Peter

 

[glenn storey]

Yes, Medite or Medex. It's the same as Extira.

 

[Grev]

Can you get Medite Moisture Resistant MDF in North America? It is a fantastic material as it is lighter than HDF but has hardened outer layers which make it ideal for bench tops. It machines well and the 19 mm thick version is my No. 1 choice for tops being made with the Parf Guide System.

In the UK it is not much more expensive than normal MDF and so one does not need to worry if you damage the top as you can soon make another.

Peter

Yes .. Roseburg Forest Products manufactures it is the US.  Not sure if it's exactly the same as in the UK, but I have both Medix and Medite  on order with my local supplier ... should have it this week.  Price quote for Medix was only about $10 more than Weyerhaeuser MDF (formerly Plum Creek), which is my favorite MDF.

Roseburg MDF

 

[Kodi Crescent]

Hi Douglas

I am in the process of making a set of videos about the Parf Guide System Mark 2 and am showing some ways to do holes at spacings other than the usual 96 mm. There are many advantages in playing around with this as long as accuracy can be maintained.

Should have something in a couple of weeks.

Peter

That's a pretty clever device, Peter.  I hope you make a mint from it.

 

[Stone Message]

Hi Douglas

I am in the process of making a set of videos about the Parf Guide System Mark 2 and am showing some ways to do holes at spacings other than the usual 96 mm. There are many advantages in playing around with this as long as accuracy can be maintained.

Should have something in a couple of weeks.

Peter

That's a pretty clever device, Peter.  I hope you make a mint from it.

Hi Kodi [member=8843]Kodi Crescent[/member]

When I did the deal neither Axminster nor I had any idea how amazing the sales would become and so, no mint, but a lot of pleasure seeing people using something that I have designed. I am told that it is one of the largest selling woodworking tools being manufactured in the UK !

I just wish my Father could have known this - he was a real engineer and just a dash of his skills have rubbed off on me.

Peter

 

[cubevandude]

I'm not sure about 5/8" M.D.F., but i know that a 4' x 8' sheet of 3/4" weighs 97 lbs. If it was me, I'd use Extira, since it's waterproof, and since I work outside most of the spring, summer and fall.

Do you have a source in Canada? I am in Southwestern Ontario.

 

[glenn storey]

I'm not sure about 5/8" M.D.F., but i know that a 4' x 8' sheet of 3/4" weighs 97 lbs. If it was me, I'd use Extira, since it's waterproof, and since I work outside most of the spring, summer and fall.

Do you have a source in Canada? I am in Southwestern Ontario.

Robert Bury. They have a warehouse in Brampton. Also, I think Goodfellow in Campbellville carries it, and if that fails, I know Rona will order it in.