Prop mods
 

After a poor response on the UK forum let's try here......Winter is here in Sweden, rescue boat out of the water and boat stripped down [:o] so time to look forward to next year.
I bought some ABC props earlier in the year to try on my Sigma from Dave. So far, just balanced and sharpened, they have been a disappointment compared to the Propshop and Octura but these have been self modded with the help of the good information found here, [link=http://rcboat.com/prop.htm]props[/link] and here [link=http://www.rcprops.com/]more props[/link]
Mod info about what works for the Propshop and Octura props is out there but not so much on the ABCs.
So, who out there is using the ABC props (specifically 3014, 2914 and 2716, all 2-blade) and what basic mods are you using and why?

Please don't refer me to the usual places to buy, I am more interested in a baseline from which to try myself.

RE: Prop mods
 

Hi Buddy,:)
What exactly do you want to accomplish with the prop mods?

The basic mod I like to do to most of mine is a Barr Cut. Size depends on application. Usually 3 - 4mm rounded is a good start. I'll help unload it & stay on pipe a little better in the turns while reducing a small amount of lift. A simple way to do this is to take a round file & start cutting. I prefere to clamp it in my mill & work it more accurately. Personally I avoid the Dremel for this application as its messy.

Another mod I like for the Prathers & Octuras is to remove the tounge (very leading edge). Round this area out nicely & get rid of the adrupt point on the entry. The ABC's don't have this as you can tell by comparison. This lets the boat accelerate much better & improves the top end on most all my rigs.

There's a few other tips & tricks but as stated first off, it depends on what you want the prop to do.

Jamie

RE: Prop mods
 

For mono mods I'd remove some leading edge and taper out. One thing to keep in mind when trying the ABC's they have a 10 degree rake so you will need to loosen the boat up to get a fair compaison, dial in the boat to the prop.

Jim has some new props out for monos and more comming soon, I can't seem to keep the new ones in stock.

I like the ABCs!

RE: Prop mods
 

Jamie the last one sounds interesting can you go into some more detail ie diagram or are there any links you can post to show how to do these mods cheers mate.

RE: Prop mods
 

Zac, that is getting right to the crux of my problem, the boat was too tight on the water and the adjustments I made were obviously not enough. The mods you mention, do you have a pic or a sketch to show how much you are removing and where? ABC's propchart shows a last update of 2004 [:o]
Jamie, I need to get the bow up and get the prop to rev out. I seem to remember reading that the barr cut was not recommended for the ABC range.

For anyone reading who wants to brush up on the terms being used (like me) try here, [link=http://sites.mercurymarine.com/portal/page?_pageid=126,48572,126_49291:126_49299&_dad=po rtal&_schema=PORTAL]Mercury[/link]

RE: Prop mods
 

Mart, here is a quick example.

The prop on the left is a stock X472 & the one on the right is one I've worked. Notice how the entry portion of the blade (tounge) is removed. This is robs a lot of speed on most boats. However, it seems to hook up much better if you run a clutch.

Having said that, the most noticable difference was on my old SuperG'. The Prather 275 that came on it was only sharp & balance... nothing more. Ran good & hooked up like a mad man from a dead stop.

Did this mod (tounge removal) and it cavitated just a tad, but produced better top end. Also, the prop on the right has been thinned. I mean THINNED down good. Its not paper, but its very noticable when comparing and RAZOR sharp.

Dasboata (chris), Shoboat (mark sholund) and a few others have been kind enough to share some of the black art with me through the years and I give them ALL the credit. I'm no expert, just a student.

Jamie

RE: Prop mods
 

Ian, you've got too much lift. A good back cut will work wonders for you. I'd mark off 1mm from the hub and file down trying to profile each blade. Run it & see how it does. Try another .5mm & run again. After about 2mm you'll see a difference. :)

Same prop, just showing an example of a back cut on the left blade.

RE: Prop mods
 

I'll get a sketch to remove tounge but Jamie hit it on the head. I'll remove 1/4" of tounge from the hub and have it tapered out by 85% of the edge towards the tip. I really don't like reducing diameter but remove just enough tounge to allow it to slip (not noticibly though) untill it gets up and going then it still has the pitch. If you have a big hull, full blade area props are good for "hole shots" as they have more bite.

Don't be afraid to give the drive/strut some positive angle. Set up may be different but I have seen some big increases in speed afterwards.

RE: Prop mods
 

Zac, I've got a box full of ABC props in various sizes that I've yet to run. (Mainly due to time limitations on the water).

What can you reccommend in the ABC's for a mono such as the Team Pro & a mid mod Zen? A nice starting point is good.

RE: Prop mods
 

Team Pro?

RE: Prop mods
 

I have modded the Octuras exactly as you say Jamie, both tongue (funny I always called them ears 'cos they are out there flapping:D) removal and back cutting Octuras and Propshops, works a treat. As you say they cavitate a bit but when they hook up...... speeeeeedd.
Zac I don't have the ABCs in front of me but that seems a lot to take from the leading edge, sure they are big blades. I can see this is going to take guts..........

RE: Prop mods
 

Ear's.... LOL
It takes a lot of nerve to cut up a good prop doesn't it. [X(]

Yeah Zac, WHH team pro. Same as the superG' running surface.

RE: Prop mods
 

Hi Ian, I had a few 3 & 4 bladed props from ABC and never bothered to work them. They are without doubt the worst props I have ever clapped eyes on. I'm sorry but compared to other props I have used they were terrible, bad castings, blow holes, lumps missing from leading edges etc. I don't work my props, my pitman Stewart does them but we both agreed they were not worth spending time on. Maybe I am missing something or I just got a bad batch but not impressed!

RE: Prop mods
 

Funny you should say that, the 2716 I have seems to be drilled off centre BUT it balances out and when I spin it the blades seem to make a centred circle around the shaft.....

Ex Marine Jamie, guess I'll find it somewhere:D:D

Thanks for the input so far[sm=thumbup.gif]

RE: Prop mods
 

Jamie... a ABC MW3 may work well on that boat. My mono ran in the high 40's low 50's with a stock 260, 57mph with mod 260 (with a stock S/B MW3).

It may like the ABC 2714/3 chopper prop as well. Only one way to find out...

RE: Prop mods
 

Ian,
The ABCs do have allot of blade area, it helps grab but IF they prop is a bit too heavy then I'd remove some tongue (a little at a time) until it is where I am happy with it. I remove tounge on mono props and do barr cuts and tongue work on hydros. My riggers love the ABC 2816/2 (mid 70s in heat trim) If you barr cut you should heat treat!!!! Or this could happen[link=http://www.americanrcboats.com/driftwood/vids/warlock.wmv]video[/link]

Listen to the RPM come up in the corner with out the barr cut it is a flat tone around the course.

Sorry for stealing your pic Jamie :eek:
http://www.americanrcboats.com/images/misc/Ql33812.jpg


Madmodel,
Some of the early props were difficult for Jim to do and did require some (and sometimes more like allot) or work to get them right. The ABCs have been getting better over the past 5 years and the newest ones are the nicest "raw" props I have ever seen, thin blades and numbers that are easily read. The 3 + 4 blade chopper props are bad to the bone for hole shots and handling.

RE: Prop mods
 

Jamie,
There are many ways to go:

2714/2
2814/2
2714/3 chopper
2714/4 chopper
2614/3 cleaver (new)
MW3

Many ways to achieve similar results but the choppers handle unbelievable not the fastest prop but impressive.

RE: Prop mods
 

the 2714/4 definetely has some good acceleration... but thats about it (from what i found with it). I tried it on my mono with mod 260 and got speeds in the low 50's. We put it on a Y6 with a QD that runs probably low 60's with a 472 and it ran had no speed to it at all with the chopper.


But it sure seems to work well on the Lazer and XXX's.

RE: Prop mods
 

you didn't say what engine you are running

RE: Prop mods
 

After trying a number of props on my mono the ABC 3014 in stock form, just balanced and sharpened, is the fastest. The 2716 with no mods was just about equal in speed but bogged in the corners. Doug

RE: Prop mods
 

GOOD POST~!

RE: Prop mods
 

Or actually it should say... GOOD THREAD~! :D

RE: Prop mods
 

My take on this is its not so much the prop mods as boat setup. Many of the prop numbers being talked about here are too big for me and might produce a good terminal speed after a 100 metres on some choppy water but for racing are a waste of time. They will run if I lift the strut a lot but then the boat handling is ugly. I like to run high rpm on my monos and a modded 7016/2 gives the best top speed on the GPS but a stock 7015/3 gives me the best laptimes by far, good acceleration out of the corners and good speed but the setup on the strut is completely different. To get the revs on the 7015/3 compared to the 7016/2 I have to lift the strut about 3mm or so and give it a touch of down angle (negative?). I don't use tabs but if the boat leans to the right I tilt the bottom of the rudder out to the right by a tiny amount (looking from the back of the boat)and that levels it up.

RE: Prop mods
 

Dave, with my stupid first setup on the Team Pro (WHH), I ran the DeepVee header & the long Hanson pipe. The best prop for it seemed to be the 7015-3 as well. Though its only playing I still liked the way the prop handled.

Here's a pic of it.

.

RE: Prop mods
 

Thanks guys for sharing your tips im going to try some of these out on my prather 280 prop :D,as allways theres different opinions on what works but i see that as constructive. I ve learnt a lot allready just from reading this thread and hope to learn a few more secrets thanks Jamie,Zac and cumon Dave i know you have more secrets too :D,liked the tip about angling the rudder a bit ill remember that one .Hey Jamie i must be stupid too cos im running a deep vee header on a hanson pipe:eek: ;).Keep the info coming guys this is the best thread in a long time.
ps Jamie that props not shiny enough :D