Brodhead Pietenpol Association

Original Posted By: Tim Willis

Original Posted By: "Phillips, Jack"
I have been around tools all my life but just recently learned of a tool that I think needs to be shared with the group. If everyone already knows about them I appologize for wasting your time. I built my lower motor mount brackets ( the ones that bolt to the fuselage) several years ago out of 14 gauge steel as called for in the plans but extended the tabs 1/4" to make room for firewall insulation etc. Drilled them and the fuselage and bolted them on. The long thin extended tabs bothered me because they looked too flimsy do do the job of supporting my extended motor mount. So I made a new set of brakets out of 13 gauge 4130. the problem I had now was, I have new blanks that need to be drilled PRECISELY to line up with the holes which were already drilled in the wood fuselage. I scratched my head for quite a while because I figured if I ran a drill bit through the wood to mark the steel the flutes of the drill bit would wollow out the holes in the wood. A center punch wouldnt fit in the small hole and even if it did it wouldn't necessarily be exactly in the center. So I made a centerpunch out of 3/16" hardened steel rod ( an old #1 phillips screwdriver) carefully clamped one half of the new bracket to the fuselage. slid the punch into the hole in the wood from the fuselage side and tapped it with a hammer. Removed the bracket and viola a centerpunch mark EXACTLY in the middle of the hole. I drilled it, pinned it to the fuselage with a bolt and did the rest the same way. After doing all the holes that way they all lined up perfectly. It worked so good I drew one up to do the 5/16" motor mount to bracket bolt holes. I took it to my machinist friend this morning and asked him to make me one out of a 5/16" grade 8 bolt. He said why make one when I have a whole set of them!!!! They are called TRANSFER PUNCHES. they look like a steel rod with a tiny little point on one end and his set has about 15 different sizes in it. I was shocked...I thought it was my great idea. I know I can't be the only one who has fought with this type of alignment problem. I had no idea that there was a tool out there designed specifically for this type of job. Like I said, If I'm the only one that didn't know about this simple but amazingly acurate tool I apologize, but they work great for any steel piece that you have to redo and I have a pile of them. Hope it helps someone out there...... Ed Grentzer________________________________________________________________________________Subject: RE: Pietenpol-List: TRANSFER PUNCHESDate: Mon, 19 Sep 2005 15:25:50 -0400