Workbench build advice

[Goesbysteve]

Hi,

I’m building an MFT style bench along the lines of Peter Millards portable.

I want to use birch ply for the frame and a ready made MR MDF top. This would be sat in my unheated, uninsulated concrete block garage year round. There is no sign of previous damp in the garage. I’m unsure if I should try to track down birch ply that has been made with water proof glue. I understand that would be desirable to reduce affect of moisture delaminating the ply. However I’ve struggled to find some in my part of mid-Wales. Before I look at further afield or delivery I’d appreciate some advice.

Is it really necessary in a garage if it will never actually be “outdoors” in the weather.
Can I offset the risk with a suitable finish?
Should I look at other ply types? Trouble is I love the look.
I could give up the portable nature and just put MR MDF on the 2x4 frame that the rest of my bench and storage will be build from.

I’d really appreciate more experienced advice.
Many thanks,

Steve

 

[Argus]

Dim cliw, Bach!

I know that when it comes to cold and dampness in this part of the world we make the stuff!

After making some kitchen gear, donkey's ago, I avoid MDF like the pox....

However, on a serious note, why not track down a typical manufacturer of the sheet that you intend using (suppliers will usually be clueless in this regard) and look for a data sheet that will/should detail its technical specifications. you may find the data that you need..... otherwise it opens a route to ask a question directly to someone who knows where it is made...... you may also get some info here, so sit tight.

Good luck.

 

[Austin Branson]

Hello Steve, I’m afraid that I cannot offer much by way of positive advice (my bench I made twenty plus years ago of heavyweight 100mm beech), but I would be very cautious about man-made materials in a concrete building. You will need to be very careful of condensation. Best wishes.

 

[Goesbysteve]

Dim cliw, Bach!

I know that when it comes to cold and dampness in this part of the world we make the stuff!

After making some kitchen gear, donkey's ago, I avoid MDF like the pox....

However, on a serious note, why not track down a typical manufacturer of the sheet that you intend using (suppliers will usually be clueless in this regard) and look for a data sheet that will/should detail its technical specifications. you may find the data that you need..... otherwise it opens a route to ask a question directly to someone who knows where it is made...... you may also get some info here, so sit tight.

Good luck.

I’ve had similar experiences with MDF. The top will be the only MDF as that’s what the commercial MFT tops are made of. They do use Medite MDF MR (Moisture Resistant) and I would use Danish Oil on it.

Diolch yn fawr!

 

[Goesbysteve]

Hello Steve, I’m afraid that I cannot offer much by way of positive advice (my bench I made twenty plus years ago of heavyweight 100mm beech), but I would be very cautious about man-made materials in a concrete building. You will need to be very careful of condensation. Best wishes.

100mm beech sounds beautiful! I guess I could do a combination on the bench top of solid hardwood and the MFT as an insert. My trouble is cost of that kind of material and ability to craft it. But I will do some research.

Thanks Austin.

 

[thetyreman]

you'll know when it's real birch ply because of the price, you want B/BB grade, why could you not use regular MDF and just seal it?

 

[Goesbysteve]

you'll know when it's real birch ply because of the price, you want B/BB grade, why could you not use regular MDF and just seal it?

Absolutely, and the price is through the roof due to obvious current affairs.

Well there is weight and I don’t really want to be cutting MDF myself. All probably something I could deal with.

Im unsure if sealing the ply I’m the same way as mdf would provide same protection.

 

[Jameshow]

Imho I would use regular ply sealed if on a budget or buffalo board if not.

The benefit of birch ply us that it takes a cuts and takes finish well.

Ext Ply will do the job for half the price.

If damp is a real issue then use buffalo board which is used of lorry decks and children's play areas.

 

[Spectric]

The top will be the only MDF as that’s what the commercial MFT tops are made of

You can get them in 18mm Birch ply Birch Ply Replacement Perforated Festool Type MFT /3 - LP Top

but with any brought in top you may be restricted on size. Making your own gives you the freedom in size and hole pattern if you don't want the maximum number of holes.

why could you not use regular MDF and just seal it

The issue is the holes, sealing it might cause problems with how the dogs fit and to fully seal would be a messy job with dozens of round holes.

Valchromat gets some good reviews and @MikeK has used this so will be able to provide better feedback.

I think of the MFT tops as being something that will need to be replaced occasionaly and not a long term item so MR Mdf is ok and using the Parf 2 to drill the holes, but really want a router solution.

 

[Goesbysteve]

You can get them in 18mm Birch ply Birch Ply Replacement Perforated Festool Type MFT /3 - LP Top

but with any brought in top you may be restricted on size. Making your own gives you the freedom in size and hole pattern if you don't want the maximum number of holes.


The issue is the holes, sealing it might cause problems with how the dogs fit and to fully seal would be a messy job with dozens of round holes.

Valchromat gets some good reviews and @MikeK has used this so will be able to provide better feedback.

I think of the MFT tops as being something that will need to be replaced occasionaly and not a long term item so MR Mdf is ok and using the Parf 2 to drill the holes, but really want a router solution.

Ah thanks I hadn’t found the ply version. Hmmmmmm. No no no no MDF makes sense. As you say it’s a long duration consumable.

I’m going the commercial route for simplicity and speed. I’d love to build a traditional English carpenter’s bench. But this is about getting something that enables me to do other work. Plus that many holes I’m going to fluff it up!

I’ve heard of Valchromat but it isn’t worth the cost to me at this point I feel.

Really appreciate the thoughts.

Thanks

 

[Jonm]

But this is about getting something that enables me to do other work.

If you want speed of construction and portability have you thought of buying your MFT top, putting it in a simple frame then setting it on trestles. The toughbuilt ones are 1m wide, the more flimsy plastic Stanley’s are 700 wide. Here is a link to a recent post Working in a small workshop
My dismantle-able bench is in there, uses the plastic Stanley’s and is surprisingly sturdy. Trestles are also useful for other jobs.

 

[Herr Nilsson]

If the garage is completely uninsulated, I think you should consider a mechanical ventilation solution - a suitably sized fan on ‘trickle’. Plus deal with any obvious draughts.

You say there is no previous signs of damp in the garage - are you certain? Have you ever pronged a moisture meter into one of the concrete blocks in winter? Rhetorical question! If there are any draughts (under doors, gaps around windows, key holes etc, then the relative humidity of the garage is likely to be close to the outside RH% with the absorbent concrete walls acting as a moisture buffer.

You mention you have a concern with ply delaminating, however, I believe you will more likely have an issue with dog holes expanding.

Currently you may not have any metal in the garage that is acting as a condensation magnet. Contrast that with the scenario of a 20mm steel dog left in a dog hole over night and you have the perfect conditions to create condensation, as MR MDF is still absorbent but to a lesser degree than standard MDF, imo.

My set up is 100% portable (I.e. no workshop), but I have a cellar room. However, I do not store my UJK mft-style bench in the cellar, as I’m certain it would screw with my worktop. Incidentally, I have a “spare”/annexed room that I’m using while I do work on the rest of the house, which is being renovated. This room has an en suite shower room with mechanical ventilation that is used daily - I swear the line of dog holes nearest the en suite now all have a very tight fit as a result of moisture ingress from the shower despite both rooms being quite well ventilated!

Have now moved the bench to the other side of the room.

..

Just a thought, but if I were going to store an MFT-style worktop in an area prone to moisture I would experiment by coating a few holes in a shellac-based primer (Zinsser B.I.N.?), i.e. a non water-based primer that causes a slight swelling of wood fibres, and see if that effects the fit of the dog holes. Very gentle rim-sand (sic) after. In all cases, I would thoroughly seal the edges of the worktop.

Good luck!

 

[Goesbysteve]

If the garage is completely uninsulated, I think you should consider a mechanical ventilation solution - a suitably sized fan on ‘trickle’. Plus deal with any obvious draughts.

You say there is no previous signs of damp in the garage - are you certain? Have you ever pronged a moisture meter into one of the concrete blocks in winter? Rhetorical question! If there are any draughts (under doors, gaps around windows, key holes etc, then the relative humidity of the garage is likely to be close to the outside RH% with the absorbent concrete walls acting as a moisture buffer.


Just a thought, but if I were going to store an MFT-style worktop in an area prone to moisture I would experiment by coating a few holes in a shellac-based primer (Zinsser B.I.N.?), i.e. a non water-based primer that causes a slight swelling of wood fibres, and see if that effects the fit of the dog holes. Very gentle rim-sand (sic) after. In all cases, I would thoroughly seal the edges of the worktop.

Good luck!

Only from a visual inspection. I’ve not been here long so I can’t tell completely. I have a moisture meter so I can check that out. I’m actually now planning on insulating it with battens 50mm from the wall for condensation barrier and breathable membrane were the wood connects to walls. Insulation between the battens. Ceiling will be done too. Unsure about floor yet. May still need to get vehicle in here.

I hear you on even minor increases in levels can cause things to swell. However I’m not going to get things to be the same as in the house. Actually the house is a 17thC solid stone building and it has its own moisture problems. I bet things wouldn’t be that much different in here.

Appreciate the reply.