Parf guide mk2 - what am I doing wrong?

[BradyS]

Evening!

I finally got to my long awaited part of drilling the workbench top with the Parf guide mk2 system. Although I followed the instructions from Peter's videos, plus the manual, plus I was well documented in the matter, things went sideways. It seems I can't get one 20mm tight hole.

My top is 24mm not 18, made of Valchromat instead of mdf. I first drilled with a Dewalt DCD996, then I tried something less powerful which is a 12V Bosch. These are the only two drivers I've got. There is some movement in the Parf guide jig, the orange part. It wobbles left-right if I'm not extra careful. I suppose it's due to the weight of the drill in conjunction with the vac hose and air suction. Not sure though, it might as well be the operator.

Any advice would be welcomed, I've worked very hard for this and don't want to ruin it.

Thank you,
Brad

 

[BradyS]

I forgot to add that I measured the thicknesses. I also drilled another piece of mdf to check. All holes show 20.20 mm, while the dogs are 19.97-19.98. The Parf guide 20mm cutter shows over 20mm in diameter in one place. Unfortunately, I can't take a photo and also hold the calipers at the same time to show it.

Can this be?

 

[Spectric]

First have you noticed that the boring bit for the 20mm holes has a central spike that cannot drill a hole, it is for location into the 3mm holes you drill first so if these are not all the way through life becomes hardwork.

Next is drilling the 20mm holes, you cannot just drill in one go as the bit clogs and you need a " woodpecker motion " as Mr Parfitt calls it where you drill and pull back and drill then repeat until through. Extraction can also help.

Now loose holes, I clamp the drill guide as it can rock but others don't and get good holes, also try and get behind the drill and not to far one side as that can tilt as you drill.

 

[BradyS]

First have you noticed that the boring bit for the 20mm holes has a central spike that cannot drill a hole, it is for location into the 3mm holes you drill first so if these are not all the way through life becomes hardwork.

Next is drilling the 20mm holes, you cannot just drill in one go as the bit clogs and you need a " woodpecker motion " as Mr Parfitt calls it where you drill and pull back and drill then repeat until through. Extraction can also help.

Now loose holes, I clamp the drill guide as it can rock but others don't and get good holes, also try and get behind the drill and not to far one side as that can tilt as you drill.

Thanks, I already paid attention and learned Mr Parfitt's instructions like the Bible. Unfortunately, it would seem that I drew the short straw and the Parf cutter I have is bigger than 20mm. I drilled other holes in mdf to check and they all end up with diameters from 20.15 to 20.20.

I have a 20mm Famag Bormax 2.0 cutter which is designed for mft holes, I drilled a hole in Valchromat as a comparison, and you can see the results in the photo below. The fit was so tight/snug that I could lift the Valchromat piece by holding the dog alone. Like it should be. The only problem with the Famag cutter is that it doesn't have the pilot spike as you call it. Nevertheless, I'll try to use that instead, see if it works. I don't really have much of a choice. I wonder if anybody else encountered this issue.

 

[MikeK]

I noticed in the first video you posted that you don't have a pin or dog on the right side of the orange drill guide. I can't remember if this is in the instructions, but the drill guide must be captured on both sides of the drill guide bushing by either a pin or a dog. This requires some thought to the sequence of 20mm holes drilling.

When drilling my worktop, I had to flip the drill guide around and use the other bushing for some rows, as this was the only way I could have it captured at both ends. I didn't clamp the drill guide, but was very careful when I drilled the 20mm holes, as I am sure you were. I used a heavy Bosch 18V drill and kept the handle in line with the drill guide to minimize any sideways rocking.

I have two of the UJK 20mm cutters, and both of them measured 19.98mm from spur to spur. I measured a few of the holes in my worktop, and they are 19.98 to 20.0 mm in diameter.

Check your email before you use the Famag cutter.

 

[Spectric]

it would seem that I drew the short straw and the Parf cutter I have is bigger than 20mm.

If the cutter is oversized then contact Axminster and get a replacement but do not use any other cutter as it is not going to fit the guide and might cause damage.

If you get issues with locating the guide at both ends because you have a 3mm hole over a 20mm hole then I found these very handy

https://www.axminstertools.com/ujk-parf-3mm-aluminium-revision-dogs-3-107359

 

[MikeK]

If the cutter is oversized then contact Axminster and get a replacement but do not use any other cutter as it is not going to fit the guide and might cause damage.

If you get issues with locating the guide at both ends because you have a 3mm hole over a 20mm hole then I found these very handy

https://www.axminstertools.com/ujk-parf-3mm-aluminium-revision-dogs-3-107359

Those look like a good idea, but Brad lives in Romania, which is part of the EU. Shipping from a UK vendor (except Wood Workers Workshop) is full of financial surprises. Fortunately, Dictum has the same item for €21, but the shipping to Romania is another €35.

 

[Keith Cocker]

I’ve done 3 surfaces now using the Axminster kit. Seems that your two problems are not clamping the orange guide fully and not using the kit drill bit.

 

[paulrbarnard]

I use the same Dewalt drill and don’t clamp, just hold in place by hand, and I’ve not had this problem. I’ve done two tops so far and both came out perfectly.
I can only think you have a duff cutter.

 

[BradyS]

Good morning and thank you all for the quick replies.

If the cutter is oversized then contact Axminster and get a replacement

I bought my set from Dictum in Germany, not from Axminster directly. They are Axi partners, not sure if I should contact them or Axi for conformity/quality issues. As Mike says, shipping is pretty expensive but in such circumstances shipping should be free. I also have solutions to receive a replacement in the UK directly and arrange personal delivery fromt here. First I need to find out how this works.

I found these very handy

I already have the revision dogs, but I appreciate you reminding me of them. That video was for reference only, I've got the same play in all holes even if I use 3 dogs instead of 2 (I have several). It's the holes.

Seems that your two problems are not clamping the orange guide fully and not using the kit drill bit

I did clamp the orange guide along the table edge with Bessey parallel clamps to be sure I have the best grip possible to me. And I only used the kit drill bit and parts, I wouldn't risk going sideways. I can't clamp it further, in the mddle of the table. Plus, that should be the role of the dogs.

I can only think you have a duff cutter

Unfortunately, everything points out in that direction. This morning I took the cutter off and tried both the Parf cutter and the Famag one, side by side, by hand and by using a drill stand, with both of my drilling machines. In all of my attempts, the holes drilled with the Parf cutter came out loose, 20.10 to 20.20mm in diameter. There is a point on the Parf cutter where the measurement from spur to spur shows 20.05mm. The rest probably is user error. I don't have the best digital calipers also but my verniers show the same, a hair over 20. Plus, the reality of the loose holes is undeniable.

 

[BradyS]

I’ve done 3 surfaces now using the Axminster kit. Seems that your two problems are not clamping the orange guide fully and not using the kit drill bit.

This is the setup I used for drilling the holes on edges. It won't budge, take my word for it.

 

[HamsterJam]

I used the same system and got good tight dog holes in 18mm MDF.
I later added a couple of extra holes but this time cut corners (I know) and didn’t clamp the guide. Those two holes are looser.

 

[Spectric]

I would approach the company you purchased from, Dictum in this case as they are the seller and get a new bit, I cannot see how they can charge postage for a replacement item they sold you in the first place.

If the guide is clamped and you still get a loose hole then it can only really be an oversized cutter so down to the seller.

 

[BradyS]

Thank you. I contacted them, see what happens.