Parf guide tolerances not that great?

[narco]

I’m just making my first Parf bench top. It’s in valchromat, and I’ve spent a while making sure it’s flat.

Firstly I noticed that the 3 mm guide doesn’t seem to fit in the Parf guide very tightly, it can wobble a bit.

I made my first row of 10, then a right angle at each end. I noticed that once I had made the 6,8,10 triangle that the Parf guide could be could  be wobbled some fraction of a Millimeter. I tried to hold everything right and drilled 3mm holes. I then put the 10th 3mm holes on each of these columns. Then I put the Parf guide between these two 10th holes and found that they didn’t line up perfectly.

Clamping things doesn’t seem to make a difference.

I tried uploading a video of 3mm guide wiggle, and one of triangle wiggle but I dont think vids are allowed.

So I just uploaded a photo of how much the hole is off by.

Is this normal?

Thanks

 

[mattgam]

Are you sure you are seating the pins fully in the holes? They sort of snap in.  Tolerances are very tight on my set.

 

[narco]

Yes I am.

I’ve been doing hours of investigation and I’ve found a few strange things, but the one that seems to be causing the problem is that the holes in the sticks are slightly too big. The pins and the drill guides don’t fit snugly in them. If I just put one pin in, through a stick and into a drilled 3mm hole, I can push the stick backwards and forwards and hear it hitting the pin on each side. I’m thinking it shouldn’t be moving at all. This is against the bigger part of the pin that is meant to be the same size as the hole.

My two sticks appear to be made out of different metals (I’m not sure if that is normal?). The one that looks more like stainless steel appears to have more play, based on the sound.

The holes at one end of the other stick seem to be messily made as you can see a dark crescent under each one, on both sides of the stick, where it is routed wider than the hole, but I don’t think this is the cause of the problem..

Also, the 10 holes seem to be slightly over 960mm apart, but I don’t think this is the cause of the problem either, as they are both the same, and holes appear to be evenly spaced. I am using a budget metre rule to measure so I could be mistaken here.

 

[narco]

Pic to show the different metals, and the crescents under holes in the top one

 

[Crazyraceguy]

I cannot speak to the MK2 version, because I have the original, but as I understand it, the whole point of the MK2 was that you don't drill "directly" through the rule. I assume that the thought was that over time (and maybe some poor handling) the holes would be worn by the drill bit, causing accuracy issues.
With the MK2, the holes in the rules are larger, to accept the guide bushing, thus insulating the rule from the cutting forces of an errant drill. However, this also introduces another clearance/tolerance point.
All in all, if you follow the directions, checking those opposite points before drilling, an adjustment cn be made.
I find this system, (V1) to be very accurate. My assembly table is 49" x 130" with the grid covering 97" of that length. This goes well beyond what the sticks (rules) can do in one length, yet it is dead-on everywhere. I have tested it, years after the original drilling, with a TSO MTR-X. This triangle can "prove" the squareness of the grid at any point, because the dogs will not fit if there is any discrepancy.
I didn't have the MTR-X at the time of drilling, since it is a relatively new item, but it sure shows the accuracy of both. The MTR-X can absolutely be trusted, because it can be turned over and used on the opposite side. If anything was off and you just randomly "found" a place where it fit, turning it over would expose the flaw immediately.
It's not because of sloppy holes either. If there is anything that people have issues with, it's that the holes are too tight sometimes. Whether it is cheap, fuzzy, MDF or humidity swelling it later, who knows? but loose holes are not the reason for the fit, in my case.
I am just one guy, anecdotal evidence at best, plus I am not even using the exact same system, but it can and does work for a lot of people. 
Here is the square, with 4 dogs in different rows/columns. There would be no reason to use it this way, it is totally locked up, in this position. It was just a test, when I first got it. There is some parallax error to the photo, but it is dead-on. I slid other dogs into the open holes while it was like this.

IIRC, mine is 25 columns and 13 rows, 325 holes.

 

[MikeGE]

Pic to show the different metals, and the crescents under holes in the top one

I think you have bad guide rules and you should return them for a good set.  I have the MK2 version and included a photo of mine that nearly duplicates your photo.  There is no offset between the 6mm holes for the guides and the layout etching on the rules.

My worktop is 1 x 2 meter 19mm Valchromat, with 200 dog holes made with the Parf Guide MK2 system.  As [member=58857]Crazyraceguy[/member] wrote, the holes in my top exceed the limits of the PG system, yet they are accurate as best as I can measure them with the tools I have.

[attachimg=1]

 

[Dermot]

I've experimented with a few different ways of making my own MFT tops, including the mk1 Parf system. The most successful (a long way from perfect) was a plastic jig (30mm collett / 20mm router bit).

However, I've given up, as none were totally successful or accurate.

My local CNC shop cut 3 of them for me for €238 (€79, @ £69, @ $85 each), including VAT, including the sheet of 18mm Moisture Resistant MDF.

All I supplied was the .dxf file and a .pdf file.

If you're even a little bit handy with CAD (FreeCad in my case), you can easily create you're own design.

In this case the corner fillets are 48mm, 24mm and 12mm. The corner chamfer is 48mm @ 45°. Each 20mm hole has a 1mm chamfer.

In your own design you could add a carry handle, screw trough, hose hanger or whatever you want.

If anyone wants the FreeCad File, DXF or step file, let me know your email address via private message and I'll send them to you (or if these file types can be posted, perhaps someone could let me know how (newbie to FOG)).

Good Luck.
[attachimg=1]

 

[Mike Goetzke]

I agree your rules may need replacing. When the MK2 came out many of us had issues with the rules. I actually needed a second replacement set plus I needed to de-burr the hole chamfers so the pins would sit flat. Contact Axminster and they should take car of you.

 

[rmwarren]

I had several components replaced by Axminster due to tolerance issues. Just ping customer service and they'll probably just ship whatever you need. I went thru 3 sets of rules, and 2 sets of pins and the 20mm drill before mine worked reliably.

FWIW, I have a very early V2 set.

RMW

 

[TSO_Products]

I’m just making my first Parf bench top. It’s in valchromat, and I’ve spent a while making sure it’s flat.

Firstly I noticed that the 3 mm guide doesn’t seem to fit in the Parf guide very tightly, it can wobble a bit.

I made my first row of 10, then a right angle at each end. I noticed that once I had made the 6,8,10 triangle that the Parf guide could be could  be wobbled some fraction of a Millimeter. I tried to hold everything right and drilled 3mm holes. I then put the 10th 3mm holes on each of these columns. Then I put the Parf guide between these two 10th holes and found that they didn’t line up perfectly.

Clamping things doesn’t seem to make a difference.

I tried uploading a video of 3mm guide wiggle, and one of triangle wiggle but I don’t think vids are allowed.

So I just uploaded a photo of how much the hole is off by.

Is this normal?

Thanks