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(02-27-2017, 10:53 AM)rwe2156 Wrote: I generally discourage the use of MDF for workbench tops unless you have them throughly waterproofed. Inevitably water borne fluids will come in contact, which is catastrophic for MDF. However, my assembly bench is of MDF and aware of this fact, I scrape, sand and dowse it in BLO 2-3 X/year.
MDF is a great material for flatness and density. I think 2-3 layers of 3/4" MDF covered with a layer of hardwood ply or masonite hardboard can make an excellent benchop. A big problem is it does not stand up well if using bench hooks or dog holes (which in all practicality eliminates its use if so desired).
Good points, all. Question: Many years ago I built the Traditional European workbench featured in Woodsmith #50. Have used it a ton over the years. I'm thinking of building another bench that is more utilitarian in nature with a larger work surface but also with a face vise and an end vise, with a larger surface that will be used also for assembly. I already have the face vise squirrelled away but was thinking of using the round brass dogs on the end vise, like those sold at Lee Valley rather than the rectangular ones on my WW workbench. I plan on using the two layers of MDF with Masonite on top of that - would this hold up over time using the round dogs?
Thanks,
Doug
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(02-27-2017, 10:53 AM)rwe2156 Wrote: MDF is a great material for flatness and density. I think 2-3 layers of 3/4" MDF covered with a layer of hardwood ply or masonite hardboard can make an excellent benchop. A big problem is it does not stand up well if using bench hooks or dog holes (which in all practicality eliminates its use if so desired).
Is the top on this bench a good solution to the problem?
http://www.thewoodwhisperer.com/viewer-p...bly-table/#!
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(02-27-2017, 10:53 AM)rwe2156 Wrote: I generally discourage the use of MDF for workbench tops unless you have them throughly waterproofed. Inevitably water borne fluids will come in contact, which is catastrophic for MDF. However, my assembly bench is of MDF and aware of this fact, I scrape, sand and dowse it in BLO 2-3 X/year.
MDF is a great material for flatness and density. I think 2-3 layers of 3/4" MDF covered with a layer of hardwood ply or masonite hardboard can make an excellent benchop. A big problem is it does not stand up well if using bench hooks or dog holes (which in all practicality eliminates its use if so desired).
I've made many a bench with an MDF top, and they end up getting sold before I can do any damage to them, but I know of 3 that are all more than 25 years old, and still used regularly. The trick to making them spill proof is nothing more than a few coats of sprayed on latex house paint, or better yet some Kilz, with a sprayed topcoat of MS/Poly mix. Spills might discolor, depending on what they are but never penetrate, and that is the problem. Moisture laying on MDF will absorb, and cause it to swell. That part being taken care of, I challenge you to find a flatter top. Plus most of mine are run over by the swiss cheeser, so they end up being similar to a MFT table, only done in 3/4" diameter. Run a large diameter round over bit into the holes, just a little bit to get rid of an edge that can curl up using dogs, clamps, and such. Saying MDF won't work will get a lot of Festool folks angry at you.
Swiss Cheeser is a 2x12 with a 3/4" edge piece. If you can't figure out how to use it I can't write that many words
To do overlaps use a few 3/4" dogs down through the last row, and keep moving. It gives you a 1 1/2" deep starter for a drill bit, so your holes should stay nice and straight. 3 or 4 layers of ply/MDF make a nice thick top, plenty enough to be able to use hold downs. Vise here or there, and you are getting busy.
Worst thing they can do is cook ya and eat ya
GW
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(02-27-2017, 11:13 AM)Tapper Wrote: I plan on using the two layers of MDF with Masonite on top of that - would this hold up over time using the round dogs?
Thanks,
Doug For dogs ok, but a bench hook will eventually wobble out the hole.
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(02-27-2017, 01:28 PM)Lynden Wrote: Is the top on this bench a good solution to the problem?
http://www.thewoodwhisperer.com/viewer-p...bly-table/#!
Looks ok. If you notice, the dog holes are in hardwood strips.
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(02-28-2017, 10:37 AM)rwe2156 Wrote: For dogs ok, but a bench hook will eventually wobble out the hole.
If you use 3 layers with 1 or 2 of them just some CDX plywood, the ply won't wallow out like the MDF can with a bench hook. The ply will lay [plenty flat, it just doens't have a flatness for the top the MDF brings to it.
So you would want from the bottom up Ply, Ply, MDF. Or MDF, Ply, MDF. Being as the CDX is a lot cheaper to buy, I'd go 2 CDX, 1 MDF.
Worst thing they can do is cook ya and eat ya
GW
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