One thing I have found when working with MDF (or any problem wood) is I use the fine screw as a Drill bit then pull it out and put the course in.
And I also screw the fine thread as a drill bit in reverse (if I'm having problems) to punch a hole before I start screwing normally. This gives me about 50% better results than If I had not in very hard woods.
Well I have used the Kreg and I have never had a problem with splitting but have to say I have never used it on PDF.I have used it on Walnut that was very old like 35 yeas and very dry. You would think it would split when it was only 3/4 , I tried it in a scrap piece and used a screw to long and went out the other side and it did not split.
I have found the Kreg to be a great tool , When in doubt be sure to try it on a scrap piece first always.
My experience with Kreg is not nearly as extensive as some others, but have used to products for at least 7 years.
I have experimented using the screws on many typed of wood, and all sorts of applications. In some applications I have rebored the pilot hole with a smalled diameter bit into the receiving piece. Have to be careful not to extend the bottom of the larger diameter hole closser than 1/8' to the end of the pocket hole or there will not be enough material to mahe a good tight joint - the screw will pull through.
I have used the bit without the jig to make straight flush holes to attach materials, too, and cut dowels to plug the remaining hole.
Do not use much MDF or OSB, but will be aware of potential problems if I do.
Just thinking about your problem I had sent some thing before and just thought about some thing else that could be the reason I have never had a problem is I do use the clamps that Kreg has to offer and that your project could be slipping causing the screw to get to close to the edge and splitting . Just a thought
LOL, I have had some strange results when the boards were not clamped properly.
Remove the screw, re-drill or plug the hole in the receiving piece, and clamp PROPERLY, then try again.
Frustrating, but some of these hard lessons are great - you don't forget them.
I mostly use MDF around the shop making jigs and the like. A friend gave me a bunch a couple of years ago because he tried to use it in a project and was unhappy with the results partly just because it weighs so much it was hard to work with for large pieces. I'm working through that supply slowly. Since I got it free it is hard to beat the cost. Of course MDF is very popular as a base for inexpensive commercial furniture with veneered finish, as well as some furniture which is not so inexpensive. I like it for jigs because it doesn't warp and it is easy to machine to a close tolerance which can make it a big time saver.
In this case I needed to make a cabinet for a new shop tool and I said what the heck, clear out some of that MDF and try out the new Kreg toy on a cosmetically unimportant project. My own idiot contribution was to ignore my previous experience screwing anything into MDF. MDF is both dense and brittle which makes it very screw unfriendly. I know that. Why I thought a Kreg was going to fix that, even with the magic screws, I'll never know. Normally I use biscuits for MDF with occasional doweling when I think the joint will take a lot of stress.
On the other hand it would have been more user friendly of Kreg to mention in the documentation that screw unfriendly materials might not be a good match without taking extra care and perhaps discussing what care that might need to be taken.
Earl Zei said:
After reading quite a few of the posts here, I'm ready to throw in my 2 cents.........I've been using Kreg (jigs and screws) for about 18 years. We build about a set of cabinets per week and in all my personal time using Kreg I think I've had LITERALLY a dozen splits occur. Almost all of them were because I had the screw way too close to the end of the piece of wood. That's working with oak, cherry, and maple mostly- a bit of hickory and walnut- and thinking about it as I type this I'll bet most of the splits were in the hickory. I have had guys that worked for me complain that they were getting splits, and I never quite figured out what they were doing wrong. I try to show them how I do things, and I get pretty good results, but with this function and with staining and finishing and just in general it seems like there are a few ways that work- but somebody can come up with a whole LOT of ways to screw things up! One of my favorite sayings has always been " No matter how much you try and idiot-proof something somebody is always coming up with a better idiot!" Please don't take offense to this- I find new ways to mess up constantly but I pretty much solve most problems by FIRST assuming there is "operator error" and trying something different. I figure since we have used probably in the neighborhood of 3-4 hundred THOUSAND kreg screws over the years (no exageration) - I think they can stand by their advertising and I sure in no way feel like there is ANY kind of deception. I did experiment with some MDF and wasn't having any luck, but for what we build we find MDF to be such and inferior product that I didn't spend very much time trying to figure it out. Since you are having this happen so much I would suggest sending a few pieces where you've had the proble to Kreg- they have always been helpful when I've called over there for advise. It's been quite a while since I've needed to talk with them but their tech guys helped me out at least 4 or 5 times over the years. You could just cut off the last few inches with the joint and screws and pop them in the mail in a box- I'll bet they'll be able to figure out what is happening. Good luck
Hi there... I am BRAND NEW to all of this. I have the small, 2 pocket hole, version of the kreg jig. I was reading your specific advice here regarding using a nickel, and I just can't seem to visualize what you are doing. Could you explain more, or maybe post a picture?
Do you have the instructions about where to put the stop collar on the drill bit?
What waa said was to move the collar a nickles width toward the working end of the bit. That will leave more wood in the piece with the hole before the screw enters the receiving piece.
Vanessa, I'm the author of that post. I started using the kreg jig at the start of it introduction on to the market, having one of the first jigs sold which was the K2 model. At that time there was no build in guages and or other devices for setting the debth collar on the drill bit. To make it easy and simple the use of a american coin the nickel was the best method I could find to set the debth collar. I had two reasons for this as it kept the drill bit from hitting the base on the jig but also prevented the bit from exiting the hole on the piece that you were going to attach the drilled piece to. The exiting of the screw left a small dimple at the exit and was a protrussion that prevented a tight connection of the wood. I have mulltiple jigs now and still use this method as an assurance to proper setting of the bit. I have about 20 years building cabinets and custom wood work as a profession and this method of setting the bit has never failed me . Ref to photo. If you do not have the type with a base on it similiar to the one below it will not apply and you will have to refer to the instruction sheet that came with the jig. hope this answers your question.
Thank you SO much. Great picture. And I can use any and all helpful tips, so I am most appreciative!
Jay Boutwell said:
Vanessa, I'm the author of that post. I started using the kreg jig at the start of it introduction on to the market, having one of the first jigs sold which was the K2 model. At that time there was no build in guages and or other devices for setting the debth collar on the drill bit. To make it easy and simple the use of a american coin the nickel was the best method I could find to set the debth collar. I had two reasons for this as it kept the drill bit from hitting the base on the jig but also prevented the bit from exiting the hole on the piece that you were going to attach the drilled piece to. The exiting of the screw left a small dimple at the exit and was a protrussion that prevented a tight connection of the wood. I have mulltiple jigs now and still use this method as an assurance to proper setting of the bit. I have about 20 years building cabinets and custom wood work as a profession and this method of setting the bit has never failed me . Ref to photo.