Parf MK II pins/dogs too tight

[rmwarren]

Wondering if anyone else has experienced trouble with the 3mm pins and 20mm dogs that are part of the MK II kit being so tight as to be borderline unusable?

As background, I have an early MK II kit (12/18) that I am only just using for the first time. I made one top using 3/4 MDO and the pins were so tight that I had to force them into the 3mm holes and use pliers to remove, but the dogs worked fine. After completing the top I reamed the holes and it work great with all my dogs. I'd reached out to Axminster about the tight 3mm holes, thinking the bit might be undersized, they quickly sent 2 replacements but they were the wrong bit, too short.

Today I started making a new top from 3/4 MDF. Same problem with the pins, even after I started using paste wax in the holes. It's unpleasant but I can manage. When it came time to start using the dogs I was happy since the last time they were much easier than the pins. Today however the 20mm holes are so tight that I couldn't pull them out without lifting the top and applying pressure from below. I was so frustrated I threw in the towel, rare for me.

I can't figure out if it's operator error or something else. Shouldn't be humidity, since no time has passed between boring the holes and the dogs sticking in them. I couldn't find any threads talking about this issue. And to be clear, I expect to have to ream the holes to final diameter to fit the the dogs I use, but I don't think I can finish this top without having to drive the dogs from the kit out after each use. I'm confused as to why they worked last week in MDO but now I'm having a problem in MDF.

Appreciate any thoughts anyone may have.

RMW

 

[TwelvebyTwenty]

Can’t help much other than to say that as a keen woodworker living in the south of England I’m very familiar with Axminster products, including their UJK stuff that is essentially the same as “Parf” products and I’ve had some trouble with QC and manufacturing tolerances with their products. You may not be to blame in my experience. May just be that the MDF with it’s more “furry” and grabby composition compounds the issue where the characteristics of MDO do not.

 

[Mike Goetzke]

I had issues with tight 20mm holes and found UJK now has a reamer that helped somewhat.

 

[Vtshopdog]

Plus one for dogs being way too tight and then getting issue solved by using their reamer.
My 3mm pins were very snug but ok.

Before reaming holes I kept a piece of 1/2” dowel around to pound stuck dogs out from below.  Slows workflow big time.

 

[rmwarren]

As stated, I plan to ream the entire top after finishing it, that's not the issue. The problem is actually finishing the top without having to hammer the locating dogs from the guide jig out of the holes after each use.

I did have issues with the MK II rules when first received from Axminster, they replaced them twice before I got a set that the holes lined up uniformly. It could just be a problem with the early production, as the MK II was just released in late 2018. It's possible that the cutter, as well as the drill bit, are both slightly undersized, or the locating dogs/pins are slightly oversized.

When I contacted them about the pin issue after making the first top, the response was "the type and density of the material you are drilling into will also have an impact on how tight the pins are" and suggested wax might help. My pins are so tight I bruised the palm of my hand by repeatedly pressing them into tight holes, then often needed pliers to remove them.

I'll reach out to them, so far it sounds like no one else has experienced the same issue.

Thanks.

RMW

 

[Crazyraceguy]

The only ones I have ever had issues with were my own fault. If you get glue down the hole, it's a problem. Reaming takes care of it though.
I'm thinking, now that I have a reamer for it, of actually putting some finish on mine. I wish I had the foresight to do it before drilling, but back then I was in a bit of a hurry to get it done.
I just recently discovered that Osmo makes an extra thin variant of their hard wax finish. I thought I might try that, hoping for little/no build-up in the holes?

 

[jacklewis]

I think the Parf guide is meant to be very low tolerance. I haven't had an issue with the dogs, but the pins can be tough to insert and remove in 18mm baltic birch. I got a blister on my thumb when drilling a workbench top.

One issue I had was that I slightly bent one of the pins from using pliers on it, which made it even harder to insert and remove.

 

[rmwarren]

Reached out to Axminster and as typical their service is excellent. They are sending new 3/20mm bits.

When researching this on the FOG prior to posting, in early 2019 Peter P did comment in one thread to the effect Axminster was inspecting all kits prior to sending them out because of issues with tolerances. Makes me believe that could be the issue since mine is 2018 vintage and wasn't tested prior to now.

RMW

Edit: [member=76497]jacklewis[/member] agree that the tolerance needs to be tight, which is why I don't think I can ream the holes before proceeding with the locating dogs. I'll probably try it but I suspect that'll be too loose and introduce too much slop. At this point I probably have nothing to loose, even if the new 20mm bit fixes the problem I can't re-bore the holes I already made so I'll have to start over.