Drilling Holes in Transom level?

[Panthrosan]

I've been reworking and fixing up my 12Ft Sears Gamefisher Jon boat and today I hit a snag. I had my new transom cut out and the two 1/2 inch plywood pieces glued together and when I clamped it back into the boat to drill the holes before sealing up the wood and I really thought that I had drilled the holes even and level but when I went to test fit the 1/4x20 bolts to attach the transom every hole it seemed was canted off at a different angle and as a result I have to scrap the transom and start over again. Any pointers on how to get the transom drilled straight? I was thinking of putting the new one I'm gonna cut up and clamp it as before but instead of drilling I will use my pencil and center punch to mark the middle of each hole and then take the transom off and use the drill press to drill the holes completely straight and level. I figure that with the holes on the plywood straight and level once I clamp it back to the boat, the 90 degree hole should match up with the angle of the aluminum back of the boat and the bolt will pull the transom and aluminum back together even and straight as well. Thoughts or suggestions?

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[marshman]

well...motor boat transoms are angled back a certain set of degrees...cant remember off the top of my head.. wanna say like 12 or 15 degrees...i dont feel like googling it...lol

anyway...i usually just stick the new transom in and clamp it or something along that line and then just drill through the existing holes...you gotta keep the drill perpendicular to the work surface, so youll be kind of drilling in an upwards direction....

OR...


you can put the back of the boat on blocks with the front on the ground or just jack the trailer tongue all the way down, or block the back up, or whatever combination will work until the transom is straight up and down(plumb), and then just keep your drill straight(level)and drill through the existing holes.......


but yes, if you predrilled the holes on a work bench, they wont work... rough lesson to learn...

 

[marshman]

i just reread your post...i had missed the last sentence or 2... you cant predrill the holes straight through the wood (perpendicular)with a drill press...the holes have to be drilled on the angle of the transom...

 

[Panthrosan]

Yeah, the woodworker in me couldn't help but keep the drill level to the ground using the built in level instead of angling it up to match the cant of the rear of the boat. I might just do the lifting the boat up until the rear is at a 90 degree angle with a level on the outside and then use the level on my drill to get the correct angle.

 

[marshman]

haha...im not a wood worker...i hate wood in fact...im a metal worker...i love the fact that if i screw up i can just weld it back and start over...cant do that with wood!!


im pretty sure i remember screwing them holes in a transom up before...

good luck...

im actually doing a transom now...got it all cleaned and cut to fit, done for the night....ill be drilling holes tomorrow...

 

[Ranchero50]

Drill halfway from each side, the second drilling op will find the first hole and you can chase into it. Not real elegant but it usually works out.

 

[BigTerp]

What I did with may transom was install it with the top two bolts so it fits nice and snug. Then just simply drill through the existing holes in the transom and through your new transom wood.

 

[marshman]

BigTerp » 25 Jul 2013, 13:27[/url]"]What I did with may transom was install it with the top two bolts so it fits nice and snug. Then just simply drill through the existing holes in the transom and through your new transom wood.

thats what i do...i clamp it, then drill the first 2 holes, bolt them 2 good and tight, then drill the rest...

 

[surfman]

You can use a small square, just hold the square with one hand at or near the point that you want to drill. Put the drill bit at the spot you are going to drill then eyeball the angle of the drill until it matches the angle of the square and start drilling. Look at the drill from the top (left right approach) and then from the side (up down angle approach) this should get you at the right angle. +/-. 

 

[bassboy1]

you cant predrill the holes straight through the wood (perpendicular)with a drill press.

Yes you can. You want the holes perpendicular to the transom, so if the transom wood is removed and sitting on a drill press, it will be about as perfect as you can get. Once it's reinstalled on the sloped transom, the holes will be exactly as they are supposed to be.

 

[marshman]

bassboy1 » 26 Jul 2013, 08:51[/url]"]

you cant predrill the holes straight through the wood (perpendicular)with a drill press.

Yes you can. You want the holes perpendicular to the transom, so if the transom wood is removed and sitting on a drill press, it will be about as perfect as you can get. Once it's reinstalled on the sloped transom, the holes will be exactly as they are supposed to be.

i stand corrected... sorry...my brain passed gas i guess... #-o #-o

 

[lckstckn2smknbrls]

I took a piece of 2x4 drilled a hole thru it on the drill press then you take the piece of 2x4 put your drill bit thru it and line it up with the hole on the transom skin.