# DIY jackplate build



## Smackdaddy53

I wouldn’t paint it. 
Post pics!


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## Gervais

Aluminum worked great and it ended up being 20% cheaper than trying to get scraps cut at a local fabricator.






























1/4” bevels cut on either side to fit the shape of the U channel and well as edges cleaned up with a 45 degree cut


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## Gervais

3” long slots marked and ready to cut







I bolted a small piece of angel to my router as a more accurate guide and used clamps as stops on the jig so I didn’t over cut. I plugged the router less than 1/16” at a time. The 1/2 bit was pushing my 2.5hp router but it worked.














I’m using 1/2” OD x 3/8” ID bushings so I can replace them and it may help it slide a little smoother.














All cleaned up.


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## Gervais

Smackdaddy53 said:


> I wouldn’t paint it.
> Post pics!


The aluminum came with some paint on it. Probably an end piece marked.


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## Gervais

U channel roughed up and holes drilled for the backing plate slots. I regular old wood blade on a skill saw cuts it like butter. I did mess up on my first cut so ended up a little short on material if you are wondering about the shape of the cuts on the bottom.


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## Gervais

Bushings cut to height. They are actually Bronze if I said brass earlier. I’ll post links of everything purchased and a total cost at the end.







Lots of sanding and polishing. I used my palm sander and went: 120g, 220g, 400g, flipped a used sanding pad and pasted some buffing compound on it, finished with a hand polish and aluminum treatment.


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## Gervais

I went with a 3” of adjustment. On the top of the plate there is 1 1/2” from the top to the slot and on the bottom of the plate 1”. This way I could always flip the plate and have another 1/2” to play with if needed.


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## Gervais

For a little extra security I made a motor clamp bracket out of 3/4” starboard. Drilled and tapped 1/4x20 threads in the plate and it came looking nice.





















jackplate is almost done. If you haven’t guessed, I worked on it last week and I’m just getting around to posting. Planning to mount it today and run it in the near future.


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## Smackdaddy53

Looking great!


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## Gervais

Just because I haven’t spent enough time on it... ha. I added some $5 amazon stainless rulers and center punched some marked on either side. I used two part epoxy so hopefully they will stay on. I figured when adjusting it might make things easier getting it level(if that’s an issue) and I’ll have some real numbers to go by in testing.


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## JET4

very nice


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## krash

Gotta love DIY initiative... Nice Job especially using basic hand tools.


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## WhiteDog70810

Nice. I wish I had known that wood working bits would handle aluminum when I made mine.

Nate


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## Guest

Very nice! Clean work brother!


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## flyclimber

OP this is pretty slick!



WhiteDog70810 said:


> Nice. I wish I had known that wood working bits would handle aluminum when I made mine.
> Nate


Be careful... They can but it's not the most ideal. Different cutting geometries on the bits.


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## Gervais

flyclimber said:


> OP this is pretty slick!
> 
> 
> Be careful... They can but it's not the most ideal. Different cutting geometries on the bits.


I had to play with the speed a little, used W40 as a lubricant to keep the aluminum from sticking to the tool, and did shallow slow cuts at a time (1/16” at most). Definitely wore all of my safety gear and had a vac hooked to the router. Still got aluminum all over my shop.


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## Gervais

I had some help mounting it up yesterday. Everything went smoothly.


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## Gervais

Unfortunately I have some bad news... it’s a little embarrassing but I didn’t achieve the results I was looking for, the biggest ones being; eliminate porpoising without having to run negative trim, slightly more speed from getting the cavitation plate above the water, and slightly higher rpms to get my motor more in the power zone(running low 5k loaded with current prop. That being said, the jackplate worked as designed and looked really good in the water. 

So, I’m going to think on it for a minute but there is a very good chance I will be taking it off and running my motor how it was de before. I could just lower it down but I don’t want the setback if it’s not needed. I could also(by design) take the u channel off and use the slot holes in the backing plate to mount that directly to the transom and can adjust the height like that wi only 5/16” additional setback. Sadly it might be going up for sale if I don’t have a use for it in the near future. My boat is limited with its hull design and I didn’t achieve any higher numbers with the jack plate. It runs 29mph with two people as it was.


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## Smackdaddy53

I wouldn’t give up on it that easily, tweak on it until you get it right, it could be the prop. Do you mind elaborating on exactly what it’s doing and not doing?


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## Gervais

Smackdaddy53 said:


> I wouldn’t give up on it that easily, tweak on it until you get it right, it could be the prop. Do you mind elaborating on exactly what it’s doing and not doing?


I’m sure the prop is not helping. I’m going to stop by the prop shop and talk to them and see what they say. Right now I’m running a 13p aluminum. A 12 was too high and the 13 is a hair low. It usually runs round 5200-5300rpm and 29mph with two guys, and gear minus my TM and battery. My prop shop is pretty good so they will let me try some props if I pay for one up front. Once I set the motor high enough to not have any spray I got a lot of cavitation in turns, some while planing, no noticeable top speed increase, a lot of prop slippage where my rpms were at 5600-6000, motor started pulling to the left pretty hard, still had to trim some negative trim to avoid porpoising, and my hole shot suffered greatly. The right prop will help greatly but might have to add a cavitation plate and the money adds up quickly.


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## Smackdaddy53

Once you start raising a motor and adding backspacing you will definitely not gain much with the same prop. It will most likely need less pitch and a little cup and possibly smaller diameter if you go stainless. Cupping a prop will aid in holding water in turns and also hole shot. Once you get the correct prop you should be fine.


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## LowHydrogen

Super nice work!!


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## flyclimber

Gervais said:


> I’m sure the prop is not helping. I’m going to stop by the prop shop and talk to them and see what they say. Right now I’m running a 13p aluminum. A 12 was too high and the 13 is a hair low. It usually runs round 5200-5300rpm and 29mph with two guys, and gear minus my TM and battery. My prop shop is pretty good so they will let me try some props if I pay for one up front. Once I set the motor high enough to not have any spray I got a lot of cavitation in turns, some while planing, no noticeable top speed increase, a lot of prop slippage where my rpms were at 5600-6000, motor started pulling to the left pretty hard, still had to trim some negative trim to avoid porpoising, and my hole shot suffered greatly. The right prop will help greatly but might have to add a cavitation plate and the money adds up quickly.


Was the 12 you tried stainless?


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## Gervais

flyclimber said:


> Was the 12 you tried stainless?


Just aluminum.


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## Gervais

Smackdaddy53 said:


> Once you start raising a motor and adding backspacing you will definitely not gain much with the same prop. It will most likely need less pitch and a little cup and possibly smaller diameter if you go stainless. Cupping a prop will aid in holding water in turns and also hole shot. Once you get the correct prop you should be fine.


Thanks,
I’ll give some stainless props a try before I give up on it.


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## Smackdaddy53

Stainless will drop RPM with the same pitch/diameter as aluminum because stainless blades do not flex as much as aluminum and are more dense. Cupping will aid in maintaining the prop grip on water so it doesn’t blow out especially in turns. The reason you are fighting the rotation of the prop more is covered in a recent thread where a guy is fighting a 25hp after raising it up. A compression plate will help this if not totally cancel it out.


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## Gervais

Smackdaddy53 said:


> Stainless will drop RPM with the same pitch/diameter as aluminum because stainless blades do not flex as much as aluminum and are more dense. Cupping will aid in maintaining the prop grip on water so it doesn’t blow out especially in turns. The reason you are fighting the rotation of the prop more is covered in a recent thread where a guy is fighting a 25hp after raising it up. A compression plate will help this if not totally cancel it out.


I didn’t try it because my prop was blowing out so much but the sink skew is almost true with the motor and was perfectly balanced almost to where I was at the height I wanted so I might be able to get away with just that adjustment. Again, I’m really just tinkering for the fun of it. I don’t need to run in 10” of water where I fish, I just like to go fast.


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## Smackdaddy53

I cut my anode fin off, they are worthless once you run them up higher.


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## No Bait / Lures Only

I had same engine on glades x n 4" jackplate n 12" pitch turbo hot shot, power tech sra 3 12" is prop I used. Turning 5850 rpm @ 33 gps raised up to 19" on 16" transom.


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## Gervais

No Bait / Lures Only said:


> I had same engine on glades x n 4" jackplate n 12" pitch turbo hot shot, power tech sra 3 12" is prop I used. Turning 5850 rpm @ 33 gps raised up to 19" on 16" transom.


Nice, that was a manual or electric JP?


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## No Bait / Lures Only

Gervais said:


> Nice, that was a manual or electric JP?


Was a Vance manual jackplate, PT sra 3 prop is best of three that I tested. Hot shot turbo did 35 but ran 6500 rev limiter n cavitation deluxe


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## Gervais

We’ll see what she can do!? Hope to get it in the water this week


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## Smackdaddy53

Not much cup but not sure how smaller outboards handle cupping. I know they are very pitch sensitive. Looks nice and chiny!


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## Gervais

Smackdaddy53 said:


> Not much cup but not sure how smaller outboards handle cupping. I know they are very pitch sensitive. Looks nice and chiny!


I went down a pitch from my from my aluminum prop to a 12. I see how it holds and what its Turning stock before getting more cup added. It does have a little lip on the trailing edge built into it vs the aluminum one.


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## Gervais

I’ve got an update. First, off thanks for all the help. I was feeling discouraged but things are looking up. The new prop is much, much better. Top speed is about the same or maybe just a touch faster (almost saw 31mph) but hole shot is definitely better and it is grabbing well. It won’t break loose in turns at WOT until I straighten out but a blip in the throttle fixes that. I thing I have the jack plate dialed in within a 1/4” or so. It has performed really well and now that I have a system, adjusting on the water takes just a few minutes. I am going to make the change from bronze bushings to SS based on some advice from a member on bronze and aluminum not getting along too well. Just got the SS in to make some today. Also, going to stop by the prop shop and consult them to see if a little cup may help or not.


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## DuckNut

Gervais said:


> View attachment 78770
> View attachment 78772
> View attachment 78774
> View attachment 78776
> I had some help mounting it up yesterday. Everything went smoothly.


In the last pic it shows the motor not bolted. Get it bolted, that plastic spacer is slippery.


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## Gervais

DuckNut said:


> In the last pic it shows the motor not bolted. Get it bolted, that plastic spacer is slippery.


Thanks, I'm planning on it now that its staying where it is. I only have one hole on either side of that motor. Also, I recessed where the clamps are roughly 1/4", so if it were to move its would only be a small amount. Those clamps bight into starboard a little as well.


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## noeettica

What's up with the sticker on the motor ? 

What do they charge for it ?


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## Gervais

noeettica said:


> What's up with the sticker on the motor ?
> 
> What do they charge for it ?


That’s SC DNR registration sticker. Charge for the power tech? I didn’t get a great deal on it. I think it was around $240


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## noeettica

I was referring to the fees for the DNR do they charge for both boat and motor ?

Do they charge by the horsepower ?


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## Gervais

noeettica said:


> I was referring to the fees for the DNR do they charge for both boat and motor ?
> 
> Do they charge by the horsepower ?


It’s just a registration fee. I think it’s all the same for any boat or motor. Not 100% sure on that.


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