CNC'd MFT top, Parf guide or Trend jig?

[Raymien]

Two CNC'd MDF tops from Wrexham are £90 delivered, as the delivery charge is £30. The trend jig is £104 and the Parf guide is a little more at £140. Seems daft spending £90 on two MDF tops, when for only a little more I can make as many tops as I want, in any shape/style I want...

Which would you do and why?

 

[marcros]

For me, it depends a bit on what you want and how often you want it. Being able to make custom sized tops is useless if you don't need to do so. If the Wrexham place does the size you need and you are trade, then it is probably not worth your time to spend an hour making one. If a top lasts you 12 months of regular use it won't owe you a lot.

I am tempted by the parf system. As a hobbiest, my time is not chargeable. I do see it as a system to use a couple of times and then it probably gathers dust. When I need a new top I will decide whether to make or buy. The bigger advantage to me is not so much the custom sizes but the custom material- valcromat, etc. I thought that the parf system was nearer to £200 actually.

 

[Mrs C]

Depends how accurate you want them and how much you trust yourself not to make a mistake. The tops last several years if you look after them.

 

[Rorschach]

How many tops do you need?

Remember you need to factor in material cost and your time to make it.

 

[LBCarpentry]

Exactly the above. Some things it’s just better to outsource. Follow the money. Spend the time working on actual commissioned work.

I’m sure I could keep myself busy all year round having “workshop days” but it’s little good if your not earning the squillah

Louis

 

[DBT85]

I bought one done on a CNC. I'd be tempted to make my own for a random size but I'm not buying the parf system just to make one. A rental option would work but sales would plummet if Axminster offered it. Considering I could draw a pattern and send it to the cnc people and they'd cut it for me its just easy that way.

John Mcrath on youtube just made a full sheet one using the jig and I tihnk it was out by 0.005 degrees.

My bigger quesion is why is it UJK and not UKJ.

 

[PerryGunn]

I used the cncdesign jig to make my MFT top, to my mind it has one big advantage over the Trend jig - it's larger at 2 rows of 11 holes verses 2 rows of 5 holes and, to quote Trend 'When using a jig there will be a cumulative error that cannot be avoided when indexing the jig on existing holes.' so the less you need to have to move the jig, the better.

I'm a hobbyist and I had a couple of reasons for making my own MFT top rather than buying one
- I wanted it slightly larger than a standard MFT and, due to floorspace constraints, build it into a wall-mounted fold down table that incorporated dog & fence storage
- As a learning experience to see if I could...

I thought about trying melamine-faced MDF or plywood for the top but settled on 22mm Medite MR MDF which I sealed with multiple coats of sanding sealer before machining

 

[Sideways]

Tricky.
I've bought a single top with the bundled dogs from Wrexham and thought it good value.
I later bought an original parf guide (£120 ish) and have used it to make various oddball tops from MFT-like in MRMDF with only the holes I wanted, to rows of dog holes down the front edge of my bench and on the Mini bench on bench ...
It doesn't get used that often but the parf jig is accurate and versatile.

 

[Raymien]

I’m a hobbyist too, so time isn’t really an issue with making one, as I’m making the rest of the bench too.
I need dog holes suitable to cut a full sheet lengthways, squarely, so my options are to build my own where I can cut holes anywhere I want, or buy two ‘pre made’ ones and fit them at opposite ends of the bench. I’m leaning towards a jig, as I can then add any parts to the bench over time, but it’s the accuracy that concerns me so I was looking to see what others thought about using a jig.

@marcros The Mark 2 parf jig is £200, but the Mark 1 is £140 at the moment.

 

[Raymien]

I used the cncdesign jig to make my MFT top, to my mind it has one big advantage over the Trend jig - it's larger at 2 rows of 11 holes verses 2 rows of 5 holes and, to quote Trend 'When using a jig there will be a cumulative error that cannot be avoided when indexing the jig on existing holes.' so the less you need to have to move the jig, the better.

I'm a hobbyist and I had a couple of reasons for making my own MFT top rather than buying one
- I wanted it slightly larger than a standard MFT and, due to floorspace constraints, build it into a wall-mounted fold down table that incorporated dog & fence storage
- As a learning experience to see if I could...

I thought about trying melamine-faced MDF or plywood for the top but settled on 22mm Medite MR MDF which I sealed with multiple coats of sanding sealer before machining

How did you find the accuracy of the jig please?

 

[Ollie78]

I get birch ply ones from a guy on ebay, they are great ( about £50 ).
I tried a jig, the type with holes where you use dogs and a router with a guide bush. I wouldn't do it again. The guide bush must be very precisely the right size and perfectly concentric for it to work well. I wasted my first top trying to get the setup perfect. It eventually worked but not worth the hassle.
Peter Parfitt's guide setup looks superior and more useful for different sized tops and things.
As mentioned it takes time to do your own and you still need to buy the materials.
For me 50 quid every 6 months is fine and no hassle.

Ollie

 

[pe2dave]

I’m a hobbyist too, so time isn’t really an issue with making one, as I’m making the rest of the bench too.
I need dog holes suitable to cut a full sheet lengthways, squarely,

How often will you need to work with two MFT's? Takes up a lot of space?

 

[Ollie78]

For cutting a full sheets I normally just put a couple of battens on the floor and use a track saw. You can be accurate if careful.
Maybe you need parallel guides ?

Ollie

 

[MikeK]

Two CNC'd MDF tops from Wrexham are £90 delivered, as the delivery charge is £30. The trend jig is £104 and the Parf guide is a little more at £140. Seems daft spending £90 on two MDF tops, when for only a little more I can make as many tops as I want, in any shape/style I want...

Which would you do and why?

After a bit of research, my choice was easy. I could not find a combination of pre-made table tops that suited me, so I bought the Parf Guide Mk2 and made my own table. I wouldn't bother with the original Parf guide, and would use the Mk2.

After talking to several shops within 50 kilometers of me that had a CNC table, only one had a table large enough for the 1x2 meter top that I wanted and he wanted €350 to cut the holes. Unfortunately, he would not guarantee the accuracy of the holes or grid pattern over the 2-meter length. The owner was upfront with me and was familiar with the MFT tops. He explained his CNC machine used a small router bit to make the 20mm holes instead of a 20mm cutter. For small tables, similar to the Festool MFT/3, there aren't any problems, but over longer distances, errors can creep in because of the gantry of his machine. I didn't want to risk a full sheet of Valchromat on a table top that might not be accurate.

I am a hobbyist and do not make any money from my projects; therefore, I do not factor my time into any of my tool and jig fabrication...it is part of the journey for me. For those interested, it took me about three hours to cut 200 holes using the Parf Mk2, and this was the first time I have ever done a project like this.

As a special tool, the Parf Guide Mk2 is a one-trick pony and has no other uses once the top is made. However, it was less expensive than paying for questionable machining, is easy to use, is accurate, and is easy to store until needed for the next bench top.

 

[PerryGunn]

How did you find the accuracy of the jig please?

Very good, it's come out accurate enough for anything I'm likely to need - dogs in the holes line up perfectly in both directions with a straight edge and the rows/columns are nice and square according to the largest square I have (600 x 300). At some point, if I'm bored, I might try the 5 cut test to see just how square it is.

A few observations on the process...

Use dust extraction.

I spent time fine-tuning the hole size using aluminium tape on the guide bush and making test cuts on scrap MDF. Some tape is supplied with the jig but I used a thinner tape that I already had
https://www.amazon.co.uk/gp/product/B07M7DBCF5
It may be a peculiarity of my router (Trend T11) but, initially, I was finding that the holes tapered slightly towards the bottom - not much but enough that a test hole that was a snug fit inserted from the top required a lot of effort to insert from the bottom. I eventually worked out that this was due to the tiny amount of play in the plunge bars and if I routed the holes with the router plunged all the way down and used the lock lever, it removed the play and the hole sizes were identical top & bottom.

When routing the holes you have to be careful about spoil getting caught between the guide bush and the side of the jig hole as this will deflect the bush (it's only a small amount but when you're tuning a hole size to ~0.1mm, it makes a difference). I adopted a technique of
- plunging in the centre of the hole
- small circular motion to enlarge the hole a bit
- raising the router bit all the way up
- tilting the router back/forward to allow the dust extraction to remove the spoil that was still in the jig hole
- plunge router bit back through the hole to full plunge depth
- lock the plunge lever
- 3-4 circular motions of guide bush around jig hole
That sounds like a faff but it takes longer to explain it than it does to do and, after the first few, it's just routine.

Before moving the jig, check every hole with a dog just in case... I had 4-5 that I had to make another pass on, possibly because a bit of spoil had not been sucked away

Each time you move the jig wipe any accumulated dust from the guide bush

The jig comes with two alignment 'pins' that locate it to the previously routed holes, but it has 3 alignment holes that can be used (left/right/centre) so I used the two supplied pins in the left/right holes and a short dog in the centre hole as an additional alignment pin

I made sure that I clamped the jig in each new position rather than just relying on the alignment pins to hold it in place.

I used a trim router with a 45deg chamfer bit to chamfer the holes slightly - I don't know if there's an 'ideal' size for the chamfer but I used the test holes to get something that looked OK to me

 

[Raymien]

All these replies are genuinely appreciated. Thank you.

I'm still torn. It sounds like the Mark 2 Parf guide is the most accurate, and so therefore seems the most sensible one to buy. I've got a decent router (Triton MOF001) but the whole concentric/guide bush issues sound like a headache, and the last thing I want is an inaccurate set of dog holes. It's just the darned price of the Mark 2 that's so off putting - £200 plus the cost of material is steep. I guess buying, using and then selling on is always an option, as like some have said, if I use decent material and look after it, it's likely I won't need to replace it for a long time.

I want a large bench around 2.6m x 1.4m. My workshop is a double garage so I've plenty of room, and I'm currently using a bench thats the size of a full sheet of 18mm hardwood ply. My original plan was to inset pre-CNC'd MFT tops at opposite ends of the bench. Giving me the option of running a 3m rail from a dog inserted in each MFT top. However it's now occurring to me that I will have to align those tops perfectly, otherwise at a distance of ~2.4m it'll be easy to go out of straight/square.

For cutting a full sheets I normally just put a couple of battens on the floor and use a track saw. You can be accurate if careful.
Maybe you need parallel guides ?

Ollie

The only problem with this I thought, was that I'm relying on the factory edges of the sheet being square. I was thinking I'd need a a long set of dog holes in order to give me a long straight square cut I could rely upon.

Am I just overcomplicating it, and I should just stick one CNC MFT top at one end of the bench and see how I go?

 

[pe2dave]

I want a large bench around 2.6m x 1.4m. My workshop is a double garage so I've plenty of room, and I'm currently using a bench thats the size of a full sheet of 18mm hardwood ply.

Understood. But do you need that bench to be an MFT? Or is that a 'nice to have'?
A pragmatic view. Build your large bench, then have the MFT for when you need to use
the tracksaw?That way, the MFT could be a smaller, commercial ply / mdf item?
Just a suggestion.

 

[sammy.se]

Hi,

As someone who has just built a medium sized MFT, and used a jig to route out the holes, I wouldn't even bother with a non-CNC'd work top in future.
Especially for a larger bench.

This is because the tiniest inaccuracy amplifies and compounds after the length of the table.

A 0.04mm inaccuracy results in 2mm errors along your length.

You have to have perfectly calibrated tools: router, template, cutter, etc.

And after all that work, it might turn out inaccurate.

That's my personal recent experience.

You are welcome to try/borrow my CNC jig for the cost of postage if you'd like.

 

[sammy.se]

I see you are in Norwich.
There is a similar threads on here, where someone mentioned an Essex based CNC manufacturer who makes custom mft tops

 

[Raymien]

Understood. But do you need that bench to be an MFT? Or is that a 'nice to have'?
A pragmatic view. Build your large bench, then have the MFT for when you need to use
the tracksaw?That way, the MFT could be a smaller, commercial ply / mdf item?
Just a suggestion.

I design and build furniture, mostly radiator covers. Everything is broken down from a full sheet of MDF. Mostly buy cut list involves pieces in the region of 900mm x 80-160mm, so manageable on a 1102 x 718mm CNC'd MFT top. However sometimes I'll need to make the top of a radiator cover for example thats 1600mm x 220mm wide. In these circumstances I need to cut from the long side of a full sheet and I want to do this squarely, and accurately. I could just continue to use my square and rule to mark it out and cut it, but I was thinking if I'm building a new bench from scratch, why not accommodate all my needs?

Hi,

As someone who has just built a medium sized MFT, and used a jig to route out the holes, I wouldn't even bother with a non-CNC'd work top in future.
Especially for a larger bench.

This is because the tiniest inaccuracy amplifies and compounds after the length of the table.

A 0.04mm inaccuracy results in 2mm errors along your length.

You have to have perfectly calibrated tools: router, template, cutter, etc.

And after all that work, it might turn out inaccurate.

That's my personal recent experience.

You are welcome to try/borrow my CNC jig for the cost of postage if you'd like.

That's very kind of you to offer, and I may take you up on it. I just need to figure out whether I need a full length of holes or not first.

I see you are in Norwich.
There is a similar threads on here, where someone mentioned an Essex based CNC manufacturer who makes custom mft tops

Thanks, I'll have a look for that post.