Routing 20mm dog holes

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Its generally accepted that a CNC'd MFT top is the most accurate,....and those holes are all done with a routering process.
As much as I quite like the idea of the Parf system, I just cant see the cost justification......I mean, in reality, just how many tops are you going to need to produce over a period of time..?
If you plan on using the MFT top as a sacrificial top and cut into it ( as I do), you can double its lifespan by just flipping it over and using the other side.
If you are not going to be using it sacrificially, it will last for years & years.

I have a Festool MFT3 and I've had it since 2016.....it still has its original top and I have yet to need to flip it over.
I also have a 2400mm x 1200mm MFT top that I use a lot for cutting & clamping on....Its more than 4 years old and is also still on its first surface.

I'm sorry, but I just dont see the justification for the Parf Guide system. 🤔
 
Its generally accepted that a CNC'd MFT top is the most accurate,....and those holes are all done with a routering process.
As much as I quite like the idea of the Parf system, I just cant see the cost justification......I mean, in reality, just how many tops are you going to need to produce over a period of time..?

I don't agree that the CNC is the most accurate and Festool does not guarantee the accuracy of their MFT tops. When I was researching designs for my workbench, AtomicRyan (from FOG) sacrificed two full sheets of MDF after failed attempts at CNC shops before he found one that didn't suck.

If you plan on using the MFT top as a sacrificial top and cut into it ( as I do), you can double its lifespan by just flipping it over and using the other side.
If you are not going to be using it sacrificially, it will last for years & years.

I have a Festool MFT3 and I've had it since 2016.....it still has its original top and I have yet to need to flip it over.
I also have a 2400mm x 1200mm MFT top that I use a lot for cutting & clamping on....Its more than 4 years old and is also still on its first surface.

A very important lesson captured for me (time will tell if it becomes a lesson learned), is to use a backer board under the worktop being cut to reduce blowout. I didn't do this. :(

I'm sorry, but I just dont see the justification for the Parf Guide system. 🤔

The best quote I had from a CNC shop within 50KM of my house was €350 to cut 200 holes in my 2x1 meter Valchromat board. The owner of the shop made smaller MFT tops for his customers, but would not guarantee the accuracy of the holes along the entire length of the board. He was confident that the holes would be 20mm ± 0.05mm, but this was not as important to me as accuracy along the X and Y axes. The cost of the Parf II Guide Kit from Axminster was less than the cost of one attempt with the CNC and I am very pleased with the accuracy.
 
Your experience of a CNC business with regard to accuracy & price is completely different to mine Mike....
My 2400 x 1200 MFT top cost me £100 in early 2018, and that included the price of the MRMDF sheet....!
Mine is bang on square and the holes are a really nice snug fit for all my dogs and clamping elements.....I did give him one of my tall Parf dogs to use to gauge the size of the holes I required. There is no slop whatsoever and I've never found the need to use any fixing knobs underneath to hold any of the dogs in place...👍
 
Your experience of a CNC business with regard to accuracy & price is completely different to mine Mike....
My 2400 x 1200 MFT top cost me £100 in early 2018, and that included the price of the MRMDF sheet....!
Mine is bang on square and the holes are a really nice snug fit for all my dogs and clamping elements.....I did give him one of my tall Parf dogs to use to gauge the size of the holes I required. There is no slop whatsoever and I've never found the need to use any fixing knobs underneath to hold any of the dogs in place...👍

You certainly have more resources available to you in the UK, as I have learned with other projects. Privately owned hobbyist workshops are not common in my area, or maybe in all of Germany, so the availability and cost of related services and tools is limited or prohibitively restrictive.

Two of my neighbors were convinced that I was operating an illegal Schreinerei business (furniture and joinery shop) because of the machine and wood deliveries to my house. The concept of anyone actually making their own furniture, fixtures, or furnishings, rather than buying it or contracting with a Schreinerei is alien. :)
 
It must all depend upon the quality of the CNC machine being used, trouble here could be if a company has invested a large sum into such a machine then they will be looking at returns and the best way to get a good return is to do batch work so minimising down time and setup. I have seen this many times, one job that stands out was getting some exhaust header flanges laser cut, it would have only cost slightly more to have twenty cut compared to just the two but why have things you don't need laying around! Looking at these MFT tops it would be easy to get people together to get a batch made but then you have the shipping cost which are not so cheap for bulky items.
 
It must all depend upon the quality of the CNC machine being used, trouble here could be if a company has invested a large sum into such a machine then they will be looking at returns and the best way to get a good return is to do batch work so minimising down time and setup. I have seen this many times, one job that stands out was getting some exhaust header flanges laser cut, it would have only cost slightly more to have twenty cut compared to just the two but why have things you don't need laying around! Looking at these MFT tops it would be easy to get people together to get a batch made but then you have the shipping cost which are not so cheap for bulky items.

Shipping is indeed a factor here.....I'm lucky I guess, to have someone who runs a CNC business nearby ( about 15 mins away and it's on my way to & from work...)
I have recommended the guy to a couple of members on here and I believe it has always been the price of shipping/transportation that has not made it viable.....Certainly, if it's a large sheet size.

The guy has a 2500mm x 1300mm capacity on his CNC and everything he has made for me has always been spot on...👍👍👍
Admittedly, the large majority of the work he does, is batch work!
 
It must all depend upon the quality of the CNC machine being used, trouble here could be if a company has invested a large sum into such a machine then they will be looking at returns and the best way to get a good return is to do batch work so minimising down time and setup. I have seen this many times, one job that stands out was getting some exhaust header flanges laser cut, it would have only cost slightly more to have twenty cut compared to just the two but why have things you don't need laying around! Looking at these MFT tops it would be easy to get people together to get a batch made but then you have the shipping cost which are not so cheap for bulky items.

When I was designing equipment, I needed two round connector backshells for a special purpose cable I was making for some military equipment. The backshell screws onto the multi-pin connector and provides the strain relief for the cable. The cost for each backshell from the two approved vendors was over $700 each, because I had to pay for the tooling setup. If I ordered 11 backshells, the cost dropped to $16 each and I didn't have to pay the tooling costs. I bought 11 and delivered the unused 9 backshells to the customer, who likely tossed them.
 
When I was designing equipment, I needed two round connector backshells for a special purpose cable
What was wrong with Amphenol, they do an a huge range of mil spec connectors in many ways and current ratings?

Only issue for me in some applications was the size and weight so another great manufacturer was Deutsch.
 
What was wrong with Amphenol, they do an a huge range of mil spec connectors in many ways and current ratings?

Only issue for me in some applications was the size and weight so another great manufacturer was Deutsch.

The 50-conductor EMI/RFI shielded connectors were from Bendix (now part of Amphenol). The compatible backshells specified by the customer were from Glenair or Sunbank.
 
You certainly have more resources available to you in the UK, as I have learned with other projects. Privately owned hobbyist workshops are not common in my area, or maybe in all of Germany, so the availability and cost of related services and tools is limited or prohibitively restrictive.

Two of my neighbors were convinced that I was operating an illegal Schreinerei business (furniture and joinery shop) because of the machine and wood deliveries to my house. The concept of anyone actually making their own furniture, fixtures, or furnishings, rather than buying it or contracting with a Schreinerei is alien. :)
This is also the case in Italy. Italians cannot believe that someone in the UK would build a kit car or a telescope.
 
Italians cannot believe that someone in the UK would build a kit car or a telescope.
But a lot of kit cars were modeled on Italian designs!

Then you have to ask yourself if we have so much ability then why as a country are we in such a mess, this is because those that cannot do just have jobs involving talking and end up in management which we must be the worst in the world for. The british cannot manage as shown by so many companies and sporting things all using foreign managers. One day we will realise that it is the engineers that make a company and not the management.
 
But a lot of kit cars were modeled on Italian designs!

Then you have to ask yourself if we have so much ability then why as a country are we in such a mess, this is because those that cannot do just have jobs involving talking and end up in management which we must be the worst in the world for. The british cannot manage as shown by so many companies and sporting things all using foreign managers. One day we will realise that it is the engineers that make a company and not the management.
Take the Lancia Stratos, an iconic Italian rally car. The 2 companies producing affordable kits are both English. When you need parts where do you look, despite the parts being from other Italian cars, the UK.
 
On a slight aside, Ive just seen a little bit of a channel 5 program called the Gadget Show,,,sadly pretty inane stuff but what caught my eye was that as part of the studio set they are using tall pegboard which to my unntrained eye looks like an MFT top,,is there a commercially available board available which is in fact MFT?
Steve.
 
What accuracy and precision are you people wanting? Seems like something very basic is getting over complicated
 
What was wrong with Amphenol, they do an a huge range of mil spec connectors in many ways and current ratings?

Only issue for me in some applications was the size and weight so another great manufacturer was Deutsch.
Amphenol make what people have already asked for, if you’re doing something new even their catalogue is missing what you need
 
Straight away i didnt like the look of the CNC pro jig. It might have been the quickest, but that alloy wrap looks too flimsy, and i can see it catching the edge of the jig and getting ripped or somehow messed up. Plus i dont really see the need for 'adjusting' the holes. That maybe reflects more on their design being sloppy than with the other 2.
Having used the CNCpro jig, the tape is used to fine-tune the hole size - this isn't because their jig isn't accurate and you probably wouldn't need the tape if your guide bush and cutter were exactly 30mm/12.7mm respectively.

The the aluminium tape plus a few test holes let you decide how loose/tight a fit you want for your dogs. I had no problems with tape 'catching the edge of the jig and getting ripped or somehow messed up', in fact it ended up so smoothly moulded to the guide bush that I had difficulty locating the end of the tape to remove it.
 
Having used the CNCpro jig, the tape is used to fine-tune the hole size - this isn't because their jig isn't accurate and you probably wouldn't need the tape if your guide bush and cutter were exactly 30mm/12.7mm respectively.

The the aluminium tape plus a few test holes let you decide how loose/tight a fit you want for your dogs. I had no problems with tape 'catching the edge of the jig and getting ripped or somehow messed up', in fact it ended up so smoothly moulded to the guide bush that I had difficulty locating the end of the tape to remove it.
Yes, the CNCPro jig with a standard 30mm bush and 12.7mm bit makes a 20.2mm dog hole - that’s the Festool MFT standard hole size. There’s a long back story to this and I wrote a blog post covering the details on the member website, but short version, Festool never intended the MFT to be used with dogs - it was a table for crosscutting and clamping - and to this day Festool have never made or supply Benchdogs.

For whatever reason Festool chose 20.2 mm as their dog hole size, and that was that. Fast forward a few years and the world discovered Benchdogs in an MFT, CNC machines become more readily available, and everyone gave a collective shrug and settled on a 20mm hole for MFT-alike benchtops and Benchdogs, while Festool sticks to ‘their’ standard.

So the CNCPro jig makes a 20.2mm hole as delivered, but lets you reduce that by adding strips of tape; I found a single turn of tape was enough to make a decent fit with regular benchdogs - and the reference dogs supplied with the jig - whereas two turns made the fit too tight. I had real issues removing the tape, so there’s no chance of it coming adrift in use.

The Trend jig uses this tape approach as well, but it’s only to adjust the fit of the bush in the jig, it doesn’t affect the hole size.

Aside from the MFT hole size back story, all,of the above is explained in the vid that was posted further up the thread. And yes, as mentioned in a previous thread, I am working on my own 10MW MFT jig that aims to resolve the slight niggles I found with each of the three I used in that video.

HTH P
 
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Having 20.2mm holes may be strange but then 96mm hole centres, I suppose 96 / 3 gives 32mm whereas with 100mm centres you would be down to 33.3 re-occuring and we do have the 32mm euro cabinet process. Must be some logic somewhere :confused:

Looking forward to Petes new 10 minute video and his jig concept, might well put the cat amongst the pigeons and giving things a shakeup is always good.
 

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