Getting MFT top made. 96mm vs 100mm & Material

[FranWood]

Morning all.

I'm getting some panels CNC routed from the Sydenhams / Avonply.com for an office desk. I also want to get a MFT top CNC cut so I figured whilst I'm paying for delivery of the other panels I may as well get them to cut and ship a MFT top for me. I've got a couple of questions regarding hole spacing and material....

1) The 'standard' hole spacing for MFT tops seems to be 96mm and I've read some threads about where this figure comes from. My question is, if I'm having one custom made, does it need to be 96mm? I would be much happier if it was 100mm as makes more sense and will be more useable to me but will I be limiting myself if I move away from 96mm? I guess as long as the holes are all perpendicular to each other it doesn't really matter but I was wondering if not using 96mm would limit me in some other way, i.e. MFT accessories etc or another reason?

2) I'm probably going to get a 2440x1220 panel cut. I imagine I would want moisture resistant MDF for a work shop and they have this in 18mm, 22mm, 25mm & 30mm. I'll get prices but I imagine 22mm might be a good option for this size?

They also stock Valchromat Coloured MDF which is supposted to be moisture resistant but I don't know how this compares to their standard MF MDF which I believe is from Medite.

This will be my first MFT so I would welcome any advice or input. Thanks in advance.

 

[Rorschach]

96 vs 100mm makes no difference if you using the MFT as a cutting surface.

I suppose there could be some benefits to the 96mm spacing if you are creating some kind of special jig that relies on the spacing of the holes, but I personally cant think of one right now.

 

[Dr Al]

Morning all.

I'm getting some panels CNC routed from the Sydenhams / Avonply.com for an office desk. I also want to get a MFT top CNC cut so I figured whilst I'm paying for delivery of the other panels I may as well get them to cut and ship a MFT top for me. I've got a couple of questions regarding hole spacing and material....

1) The 'standard' hole spacing for MFT tops seems to be 96mm and I've read some threads about where this figure comes from. My question is, if I'm having one custom made, does it need to be 96mm? I would be much happier if it was 100mm as makes more sense and will be more useable to me but will I be limiting myself if I move away from 96mm? I guess as long as the holes are all perpendicular to each other it doesn't really matter but I was wondering if not using 96mm would limit me in some other way, i.e. MFT accessories etc or another reason?

2) I'm probably going to get a 2440x1220 panel cut. I imagine I would want moisture resistant MDF for a work shop and they have this in 18mm, 22mm, 25mm & 30mm. I'll get prices but I imagine 22mm might be a good option for this size?

They also stock Valchromat Coloured MDF which is supposted to be moisture resistant but I don't know how this compares to their standard MF MDF which I believe is from Medite.

This will be my first MFT so I would welcome any advice or input. Thanks in advance.

The main disadvantage that I can see of using 100 mm will be the inability to use any accessories that use two or more holes, for example the UJK assembly square.

 

[Sideways]

Valchromat is harder, uniform all the way through and more expensive than medite.
It machines well and makes a very nice top but if you plan to cut through into it, I'd save some money and settle for medite.

 

[shed9]

The 96mm standard is just a throw back to post WW2 standards that were agreed relevant to on centre standards of 32mm at the time (based on gear's actually if it's of any interest). That led to other aspects adopting that standard such as door hinges, etc. In other words, 32mm was chosen as a standard and 96mm is merely a multiple of it.

If 100mm makes more sense and is more useable for you then go with it, it may impede some tools that are based on the 32mm spacing but do a little research to see if that's a show stopper for you (see comment above from Dr AI). The important aspect of the holes is the diameter of the holes themselves. You will get more options using 20mm holes essentially.

Also be aware that if you are using this as a cutting surface, it may make more sense to have the surface itself supplied in two separate (possibly cheaper) sections. One large piece to the left, say around 1600x1220 and one smaller piece to the right (or reverse if left handed) of around 740x1220 and then use the middle 100x1220 section as a sacrificial piece to swap out when it gets beyond use. Just place a standard sheet under it all for strength and in the long run it will be cheaper. If that makes sense at all.

MRMDF is the better option and the Valchromat is really dependent on if you want a different colour and your budget. I suspect if they are stocking Valchromat then chances are the MRMDF is probably a known brand like Medite but worth checking and asking their opinion anyhow.

 

[Rorschach]

The main disadvantage that I can see of using 100 mm will be the inability to use any accessories that use two or more holes, for example the UJK assembly square.

Ahh there you go, I wasn't aware of that product. Though personally I am not quite sure of it's usefulness? If you have an MFT and dogs, why do you need a square?

 

[shed9]

Ahh there you go, I wasn't aware of that product. Though personally I am not quite sure of it's usefulness? If you have an MFT and dogs, why do you need a square?

In reality that UJK tool is just a CNC'd piece of Valchromat, the OP could always get one cut with 100mm adjusted spacing at the same time.

 

[Dr Al]

Ahh there you go, I wasn't aware of that product. Though personally I am not quite sure of it's usefulness? If you have an MFT and dogs, why do you need a square?

I'm not sure that you do, it was just the first example I could think of having seen them in the catalogue.

 

[Rorschach]

I'm not sure that you do, it was just the first example I could think of having seen them in the catalogue.

Sorry that was a rhetorical question not aimed at you.

 

[Spectric]

If you have an MFT and dogs, why do you need a square?

Very good question, something I am pondering with. In both cases you still need the track but with a fence and flagstops on an MFT you can setup for repetative cuts whereas with the square you need to mark each cut. But now the Mk11 Benchdogs square can be fitted with a parallel guide stop so this clears this argument. I suppose with a square you will not be cutting into the MFT top, and it is more portable. Both can allow you to use the edge for routing, perhaps the MFT in it's current guise is showing it's age.

I don't use an MFT but do have some boards that I can lay on my workbench when needed, they have 20mm holes strategically placed for location and alignment of work pieces, with routed dovetail groves for microjig clamps and accessories. I do have the Benchdog fence just for the flagstops.

I used the Parf guide for drilling the 20mm holes and found that you get a much tighter fitting dog when the hole has been drilled with the guide clamped firmly down, easy to do with holes round the edge but not in the middle, but with the dovetail groves and microjig clamps it was possible to ensure the guide was always clamped even though I only have a limited number of holes in the centre region.

So for me I may go down the Mk11 Benchdogs square route but I do not think that any method stands out above the others and it is what someone prefers or has got used to. The one thing that is apparent is that whatever you decide to use there will be something different coming along to tempt you to spend some cash.

 

[Rorschach]

Very good question, something I am pondering with. In both cases you still need the track but with a fence and flagstops on an MFT you can setup for repetative cuts whereas with the square you need to mark each cut. But now the Mk11 Benchdogs square can be fitted with a parallel guide stop so this clears this argument. I suppose with a square you will not be cutting into the MFT top, and it is more portable. Both can allow you to use the edge for routing, perhaps the MFT in it's current guise is showing it's age.

I don't use an MFT but do have some boards that I can lay on my workbench when needed, they have 20mm holes strategically placed for location and alignment of work pieces, with routed dovetail groves for microjig clamps and accessories. I do have the Benchdog fence just for the flagstops.

I used the Parf guide for drilling the 20mm holes and found that you get a much tighter fitting dog when the hole has been drilled with the guide clamped firmly down, easy to do with holes round the edge but not in the middle, but with the dovetail groves and microjig clamps it was possible to ensure the guide was always clamped even though I only have a limited number of holes in the centre region.

So for me I may go down the Mk11 Benchdogs square route but I do not think that any method stands out above the others and it is what someone prefers or has got used to. The one thing that is apparent is that whatever you decide to use there will be something different coming along to tempt you to spend some cash.

I don't have an MFT at the moment but I do have a homemade "holey" bench. There is a grid of hole that I use dogs and clamps in but they are not accurate enough to be called an MFT. Basically it allows me to clamp stock for working on and cutting but I cut using measured and marked lines for the track saw. It works well enough for my uses at the moment.

I considered getting an MFT top and making a bench but never got round to it. With things like the benchdogs square becoming more affordable and functional I am now thinking that even if I do have a job that requires a lot of cutting I probably don't need an MFT style top at all if I had the square.
I have no difficulties getting a straight edge and then cutting a parallel edge to that just using my track and a tape measure, so I don't need an MFT there, the only job I do struggle with is getting a square edge and I think a rail square would solve that problem in a reasonably priced and very portable way.

 

[Spectric]

It sounds like you are thinking along the same lines as myself, the rail square will give you a square edge and when you watch the videos on the so called five cut test the results are very good. Even though my 20mm holes are accurate and give true 90° corners I am finding it more useful just to stop work moving in conjunction with the microjig clamps. I got the Benchdog fence and flagstops not for cutting with a tracksaw but trying to get accurate hole locations with my Domino 700 that can be really hit and miss unless you use the sloppy setting which I just cannot accept. I am looking at corded tracksaws at the moment and for me the Makita SP6000 looks like the all round best option, I will not consider Festool as I think having got a Domino it shows their quality is comparable to Bosch & makita but no better and the Maefell is a better option but just overpriced in my opinion for what I need.

https://www.best10rated.co.uk/best-...MI7oiHzs3u7wIVj9rVCh0F8wXGEAAYASAAEgLtq_D_BwE

 

[petermillard]

The Benchdogs rail square is tapped to accept ‘MFT dogs’ on 96mm centres, so you can lock the square onto an MFT top instead of using rail dogs or tall bench dogs for the rail to bear against. That’s something that couldn’t be used if the OP went for 100mm spacing. Note that you could also get hit for an additional layout charge if you switch to 100mm centres - deviation away from the ‘standard’ and all that.

FWIW I always route a sacrificial strip into MFT tops on the cut line, as it can be easily replaced and extends the life of the top considerably. I’ve shown the process in many videos; there’s a playlist with all MFT- related vids here, just FYI - http://bit.ly/MFT-related

HTH P

 

[Spectric]

Hi Peter

Yes been looking at many of your videos on rail squares and the FC domino alignment jigs, its the next best thing to being able to actually handle the products.

 

[FranWood]

Thanks for the replies all, much appreciated.

So it sounds like there are a few accessories that would benefit require 96mm centers. What I guess I really should be asking, myself more than anyone, is apart from being a lovely nice round number, what benefit would 100mm spacing give me over 96mm spacing?

My inexperience with MFTs is going to show here but I guess the dogs are not really used as a 'reference for length', more so they're used just to keep things perpendicular/square? i.e if I wanted to cut a piece 100mm longer than the last piece, I wouldn't have my part pushed up against a set of dogs and then shift the dogs back a set, and in fact you don't push up 'horizontally' against a dogs at all. For a length stop/adjustment I would use a bench dogs fence and stop?

Saying that, if you did have your holes on a 100mm spacing, you could move the benchdogs fence say 5 dog holes along and you could then use the bench dogs fence/scale with a 500mm offset.

I'm not too bothered if I can't use every accessory that requires 96mm dogs. I do have a 3D printer and I have access to a few 5 axis metal cutting machines at the office so things can always be modified or made from scratch if needs be.

If 100mm makes more sense and is more useable for you then go with it, it may impede some tools that are based on the 32mm spacing but do a little research to see if that's a show stopper for you (see comment above from Dr AI). The important aspect of the holes is the diameter of the holes themselves. You will get more options using 20mm holes essentially.

Also be aware that if you are using this as a cutting surface, it may make more sense to have the surface itself supplied in two separate (possibly cheaper) sections. One large piece to the left, say around 1600x1220 and one smaller piece to the right (or reverse if left handed) of around 740x1220 and then use the middle 100x1220 section as a sacrificial piece to swap out when it gets beyond use. Just place a standard sheet under it all for strength and in the long run it will be cheaper. If that makes sense at all.

Thank you. It sounds like 20mm is the way to go for hole diameter. The board definitely needs a sacrificial part to it. I was thinking of having a trench/recess in the sheet to put a replaceable sacrificial piece in. .

FWIW I always route a sacrificial strip into MFT tops on the cut line, as it can be easily replaced and extends the life of the top considerably. I’ve shown the process in many videos; there’s a playlist with all MFT- related vids here, just FYI - http://bit.ly/MFT-related

HTH P

Thanks Peter. Thanks for all of the videos too. I've watched most if not all of your MFT videos over the last few months and they've been a great help!

I was thinking I would prefer a recess in the board as opposed to separate pieces as this would ensure that all of the CNC routed holes would be machined together and save needing to align them later on.

So far I'm thinking of something like this for the top alone:

The holes pitch is 100mm and the holes either side of the recess are 200mm apart to keep the overall pitch. The recess is 100mm wide and 13mm deep (currently modelled on a 22mm sheet). I thought I could then use 12mm sacrificial material. I went for a 13mm deep recess as 12mm material isn't always 12mm and this would allow me to shim the recess depending on the material used.

I've just moved house and I'm setting up a workshop. For a start, I'm thinking of just building a basic frame for the MFT top like the one in [this] video from John McGrath to get me started.

Is there any thing I'm missing at this point or is there anything I should think about adding etc before I get this quoted?

 

[Rorschach]

The only benefit I can think of (at the moment) to 100mm hole spacings is that you could use the dog holes as stops for 100mm spacings which might have some benefit when creating metric cabinets which often come in 100mm size increments. Whether in practise that would have any use though I couldn't say.

I think Keith at Rag n Bone Brown made his MFT top with 100mm spacings, worth a message on facebook maybe?

 

[Spectric]

what benefit would 100mm spacing give me over 96mm spacing

Nothing at all, if I were setting the spacing it would have been 100mm, nice round figure but going with 96mm like it or not is going with the flow and seems to have been set as the standard. It will also mean that when you hit an issue and find a solution that uses these benchdogs you know you will be compatable and future proof. Upto recently it would have made no odds to myself, I only used 96mm because that is what the Parf system delivers but now with the Benchdogs rail square that locates in two holes at 96mm centres maybe I have got a reason. It has to be said that 100mm must be more logical than 96mm because my dovetail slots for the microjig clamps have been routed on 100mm centres in the locations I used them.

 

[ian33a]

If you can have 96mm, I would go for it above 100. OK, with 100, the maths is easier but you may encounter issues with attaching some guides and fences. That said, the Benchdogs fence has adjustable dog positions (The UJK one, I think, is fixed at 96mm increments) and dogs to fit rail guides for saws can be placed wherever you wish. As Peter said, the Benchdogs rail square is tapped for 96 so, if you ever wish to attach one, you wont be able to lock the dogs into the table. You can have dogs which butt against the edge of the bench but you loose registration against the MFT grid if this is, for any reason, fractionally un-parallel with the MFT insert(s).

I'm in the process of building an assembly bench at the moment. In my unit I will have dual MFT (96mm) grids and plan to drill them using the Parf II system. I'm also using black Valchromat for the MFT's and have Medite for shelving underneath. FWIW, I think the Valchromat looks really nice and a lot less utilitarian than the Medite. Not that the Medite looks bad. I plan to use MFT protectors wherever possible as well as B collars as I want to protect the top of the bench. I have the luxury of it as a DIY bench and don't rely upon it for business use. Were it used all day everyday, I can see the MFT getting chewed quite easily and the Valchromat becomes a bit extravagant in that situation.

Which every way you go, I would advocate moisture resistant MDF. The stuff is horrible enough to deal with at the best of times and, if damp it's even worse.

BTW: if you go down the black Valchromat route and decide to cut any of it yourself, use a proper mask and decent dust extraction. While no different to normal MDF, often being coloured, you get to see everywhere that the clouds of it end up. My workshop ended up looking like the aftermath of a volcanic disaster ... and I was careful with it too!

 

[MikeK]

Is there any thing I'm missing at this point or is there anything I should think about adding etc before I get this quoted?

As others wrote, the choice of 96mm or 100mm depends on what you plan on using with the worksurface. If you are going to use the hole grid as an alignment pattern for bench dogs and rails, it doesn't make any difference. I used the UJK Parf Guide to make the holes in my top, so it has a 96mm pattern. However, so far I would have been just as happy with a 100mm pattern.

When selecting the thickness of the top, consider what kind of clamps you will be using. If you use the Festool or Bessey clamps that fit through the holes and clamp the work piece to the surface, a thick top might not allow the clamp to pass through the table without chamfering the bottom of the holes. I don't have any problems with the 19mm top, but I have a small worktable in my garage that is about 22mm thick that won't work with the clamps because they can't make the bend through the holes. I haven't been bothered to chamfer the holes because it is small enough that I can use F-clamps along the edges to hold the work piece.

Give some consideration to the width of the table and how many times you might be reaching across the 1.2 meter width. My MFT-style workbench is one meter wide and two meters long. I have not needed the full width for any projects yet and normally put the fence near the middle of the table when cutting with the tracksaw. The width is perfect for the FS 1400/2 guide rail and gives me plenty of overlap should I ever need to cut a one-meter width.

Think about the dimension and location of the cross support beams for the top will be so they don't interfere with the dog holes. Here is an image of my workbench without the top. The workbench is also my assembly table and I am not gentle with it. I didn't want to risk breaking the 19mm Valchromat top, so I put four 40x40mm cross beams along the length of the table.

Here is an image of the unfinished top with the sacrificial HDPE strip. The strip runs along a row of holes and the track saw guide rail is slightly off center. This allows me to rotate the strip 180 degrees when it becomes too chewed up from the saw. I have five spare strips, so I should be good for a few years.

 

[Padster]

I used The PARF MKII to make my MFT and have been exceptionally happy with it. I have rails for my Bosch plunge saw and can make great cross cuts, was going to put a sacrificial strip in, but have found I don't need it as I have bought a number of accessories from Benchdogs including the 3mm protectors, these come with a sort of silicon top you can add making them 6mm I place these under my workpiece and ensure the depth guide is set accordingly and so far no issues and still a smooth complete work top!