Overhaulin a 60/80 Ovalmaster

[the german]

Hi guys

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Keep you updated !

Thxs

Alex

 

[MarkDanielsSr]

That was designed and built as a 40 boat. The 60/80 boat is 42" long. It will work, I have run 80 and even a 90 in that hull. It will take more driving and less wide open throttle. A good friend, now gone, Scot McGuffin from Baytown Texas made a similar boat called the Witchcraft, we in New Orleans had easily ten of them set up with 65 and 80 motors. Scot came oveer for a Mono Invitational and beat everyone in open class with his 40 Witch, laughing at dinner that evening stated he had made the boat for a 40 motor and it was the best choice. Just some old information. If you want I can send you pictures of the 60/80 and the 90 Oval Master boats, there is no mistaking them, the 45 is the only one with that deck. Mark

 

[David Bryant]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

 

[the german]

That was designed and built as a 40 boat. The 60/80 boat is 42" long. It will work, I have run 80 and even a 90 in that hull. It will take more driving and less wide open throttle. A good friend, now gone, Scot McGuffin from Baytown Texas made a similar boat called the Witchcraft, we in New Orleans had easily ten of them set up with 65 and 80 motors. Scot came oveer for a Mono Invitational and beat everyone in open class with his 40 Witch, laughing at dinner that evening stated he had made the boat for a 40 motor and it was the best choice. Just some old information. If you want I can send you pictures of the 60/80 and the 90 Oval Master boats, there is no mistaking them, the 45 is the only one with that deck. Mark

That would be awesome Mark if you can send or post old pics !

Appreciated

Alex

 

[the german]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

Thxs Dave for all the informations.The motor is a 80 Rossi drum valve for sure ( I know they used the 61 case also for the 80 motors) and the hull is 37.5"long.

I was thinking about to machine my own T-bar to support the shaft and a light aluminum tray for the tank bolt to the rails.

The old flex shaft is 3/16 12"long but i was thinking a 1/4 flex shaft is a little stronger and not as easy to break.

Btw any suggestions about the tank size ( 16 oz or more ?)The turn fin what i have looks the same as in your pic but i didn't thought about a skeg under the motor.

Alex

 

[SayMikey]

Jim Irwin had the molds. I borrowed it and built one. I gave it to a friend and he put a gas motor in it. Good running boat

 

[David Bryant]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

The motor is a 80 Rossi drum valve for sure ( I know they used the 61 case also for the 80 motors) and the hull is 37.5"long.

I was thinking about to machine my own T-bar to support the shaft and a light aluminum tray for the tank bolt to the rails.

The old flex shaft is 3/16 12"long but i was thinking a 1/4 flex shaft is a little stronger and not as easy to break.

Btw any suggestions about the tank size ( 16 oz or more ?)The turn fin what i have looks the same as in your pic but i didn't thought about a skeg under the motor.

Alex

Yeah, 37.5in OAL is definitely moreso suited for a "40" class mono (or .45ci/7.5cc engine displacement). While the Rossi R80RV drum-valve will work well, .45 displacement will provide a more "balanced" combination, as Mike mentioned above. Better overall handling, and good speed.

I believe I'm using twin 8 ounce Sullivan slant tanks, side-by-side. I have plywood plate (1/8in thick) laminated to floor (along with plywood cross-brace) forward of engine as tank "platform". But I guess an aluminum plate will do the same thing. Same for aluminum shaft-log support. I prefer laminating plywood bulkhead(s). I probably would re-do the shaft-log, using new brass tubing, re-aligning/setting strut position and all the main drive-line (that's just me

)

3/16 X 12in flex-shaft is fine (for the prop sizes used with the Rossi R80RV, but 1/4 is better.

I've had more stable performance using, both, a center mounted turn-fin in-conjunction with a transom mounted spin-fin.

 

[the german]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

The motor is a 80 Rossi drum valve for sure ( I know they used the 61 case also for the 80 motors) and the hull is 37.5"long.

I was thinking about to machine my own T-bar to support the shaft and a light aluminum tray for the tank bolt to the rails.

The old flex shaft is 3/16 12"long but i was thinking a 1/4 flex shaft is a little stronger and not as easy to break.

Btw any suggestions about the tank size ( 16 oz or more ?)The turn fin what i have looks the same as in your pic but i didn't thought about a skeg under the motor.

Alex

Yeah, 37.5in OAL is definitely moreso suited for a "40" class mono (or .45ci/7.5cc engine displacement). While the Rossi R80RV drum-valve will work well, .45 displacement will provide a more "balanced" combination, as Mike mentioned above. Better overall handling, and good speed.

I believe I'm using twin 8 ounce Sullivan slant tanks, side-by-side. I have plywood plate (1/8in thick) laminated to floor (along with plywood cross-brace) forward of engine as tank "platform". But I guess an aluminum plate will do the same thing. Same for aluminum shaft-log support. I prefer laminating plywood bulkhead(s). I probably would re-do the shaft-log, using new brass tubing, re-aligning/setting strut position and all the main drive-line (that's just me

)

3/16 X 12in flex-shaft is fine (for the prop sizes used with the Rossi R80RV, but 1/4 is better.

I've had more stable performance using, both, a center mounted turn-fin in-conjunction with a transom mounted spin-fin.

Thxs again David for all the info's

Do you have a pic or any measurements for the small center mounted turn fin ?

Alex

 

[David Ashcroft]

Hey Mark I not sure what that hull is but I got a witchcraft I will post pic

 

[dr gary turner]

Mike, do you still have the mold?

 

[David Ashcroft]

I cant load the Pic but if you look in my gallery pics you will see the yellow Withcraft..

gallery 5625 1094 10969 - Monohulls - Gallery - Intlwaters Community Forum.html

 

[David Ashcroft]

Hello the German run 1/4 flex shaft with a 3/16" stub shaft because the props you will need to use will be 3/16" shaft depending on if you using a 67 or 80 props will be for example x460 x462 x465 etc...Use a main tank around 20oz and a hopper tank around 2 or 4oz..enjoy

 

[David Bryant]

Hey Mark I not sure what that hull is but I got a witchcraft I will post pic

I cant load the Pic but if you look in my gallery pics you will see the yellow Withcraft..

Nice. Looks very similiar to Youngblood mono design

 

[David Ashcroft]

Thanks David.. it is very similar to a youngblood mono however it has a sharp keel and no ride pad.

This hull was sold as a witchcraft..here where I am from.

 

[David Bryant]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

The motor is a 80 Rossi drum valve for sure ( I know they used the 61 case also for the 80 motors) and the hull is 37.5"long.

I was thinking about to machine my own T-bar to support the shaft and a light aluminum tray for the tank bolt to the rails.

The old flex shaft is 3/16 12"long but i was thinking a 1/4 flex shaft is a little stronger and not as easy to break.

Btw any suggestions about the tank size ( 16 oz or more ?)The turn fin what i have looks the same as in your pic but i didn't thought about a skeg under the motor.

Alex

Yeah, 37.5in OAL is definitely moreso suited for a "40" class mono (or .45ci/7.5cc engine displacement). While the Rossi R80RV drum-valve will work well, .45 displacement will provide a more "balanced" combination, as Mike mentioned above. Better overall handling, and good speed.

I believe I'm using twin 8 ounce Sullivan slant tanks, side-by-side. I have plywood plate (1/8in thick) laminated to floor (along with plywood cross-brace) forward of engine as tank "platform". But I guess an aluminum plate will do the same thing. Same for aluminum shaft-log support. I prefer laminating plywood bulkhead(s). I probably would re-do the shaft-log, using new brass tubing, re-aligning/setting strut position and all the main drive-line (that's just me

)

3/16 X 12in flex-shaft is fine (for the prop sizes used with the Rossi R80RV, but 1/4 is better.

I've had more stable performance using, both, a center mounted turn-fin in-conjunction with a transom mounted spin-fin.

Thxs again David for all the info's

Do you have a pic or any measurements for the small center mounted turn fin ?

Here are a few shots of my Steve Muck, Spartan Streaker mono. OAL is 39in.

I've been re-working the inside radio-box rails, there is noticeable sanding dust. Otherwise you can see internal layout of floor structures (bulkheads, etc.,...).

Also you can see drive-line arrangement: stuffing-box, shaft-log, strut, turn-fin, and rear transom hardware.

PS: I will go back and get turn-fin measurement

 

[the german]

Last week i started to overhaul an 60/80 Ovalmaster Mono .

I'm open for any suggestions ( propsize ,3/16 or 1/4 flex shaft, propheights etc.)

Nice mono hull. Can you actually measure and confirm OAL length?

Also would be nice to see image of hull bottom surface.

Nicely constructed radio box. Definitely seal thoroughly with epoxy and finish with fuel-proof paint.

I would fabricate 1/4in plywood bulkhead (across engine rails) and epoxy/fiberglass forward of radio-box to provide structural support for shaft-log.

Fabricate 1/8in plywood floor-plate and bulkhead for fuel tank(s) forward of engine mount area.

Make sure to thoroughly sand fiberglass floor before laminating parts.

Rossi R65RV or R80RV drum-valve engine, which size? Should work great with this hull.

Both, .187in (3/16in) or .250in (1/4in), diameter flex-shaft function well for this application (length of flex-shaft).

I run a Rossi R65RV drum-valve in a 40in Muck spartan hull.

I'm using a Prather strut assembly (pictured below) set at 3/4in to 7/8in depth sub-surface. A Prather shaft-log (No. 8041- thick-wall brass tubing bends nice and strong).

A Prather, or equivalent, 3/16in dia X 12in length flex-shaft. Octura X450 to X452 prop. An extremely fast set-up set-up.

You can use a SpeedMaster rudder assy, or equivalent.

I use a right-side (starboard) transom mounted spin-fin. Also use a conventional center mounted turn-fin with front-edge approx at CG (under engine).

The motor is a 80 Rossi drum valve for sure ( I know they used the 61 case also for the 80 motors) and the hull is 37.5"long.

I was thinking about to machine my own T-bar to support the shaft and a light aluminum tray for the tank bolt to the rails.

The old flex shaft is 3/16 12"long but i was thinking a 1/4 flex shaft is a little stronger and not as easy to break.

Btw any suggestions about the tank size ( 16 oz or more ?)The turn fin what i have looks the same as in your pic but i didn't thought about a skeg under the motor.

Alex

Yeah, 37.5in OAL is definitely moreso suited for a "40" class mono (or .45ci/7.5cc engine displacement). While the Rossi R80RV drum-valve will work well, .45 displacement will provide a more "balanced" combination, as Mike mentioned above. Better overall handling, and good speed.

I believe I'm using twin 8 ounce Sullivan slant tanks, side-by-side. I have plywood plate (1/8in thick) laminated to floor (along with plywood cross-brace) forward of engine as tank "platform". But I guess an aluminum plate will do the same thing. Same for aluminum shaft-log support. I prefer laminating plywood bulkhead(s). I probably would re-do the shaft-log, using new brass tubing, re-aligning/setting strut position and all the main drive-line (that's just me

)

3/16 X 12in flex-shaft is fine (for the prop sizes used with the Rossi R80RV, but 1/4 is better.

I've had more stable performance using, both, a center mounted turn-fin in-conjunction with a transom mounted spin-fin.

Thxs again David for all the info's

Do you have a pic or any measurements for the small center mounted turn fin ?

Here are a few shots of my Steve Muck, Spartan Streaker mono. OAL is 39in.

I've been re-working the inside radio-box rails, there is noticeable sanding dust. Otherwise you can see internal layout of floor structures (bulkheads, etc.,...).

Also you can see drive-line arrangement: stuffing-box, shaft-log, strut, turn-fin, and rear transom hardware.

PS: I will go back and get turn-fin measurement

Nice boat Brian and thank you !!!

Alex

 

[SayMikey]

Mike, do you still have the mold?

No But it should be at his house. And his daughter wants all that stuff gone. Dave Roach might be able to come up wth it

 

[MarkDanielsSr]

Hey Doc,

You know Don was a friend of mine for a long time. Several years before the big hurricane down here I bought the molds, the name, and the existing stock for Oval Master boats from him and have had them in my possession ever since. Unlike that turkey in Florida who sold me a set of molds and also sold sets to several other people for the Hitech line of hulls, Don was a stand up guy and only sold to one person, me. I have his originals for the 20 boat, the 40 boat, the 60/80 boat and the 90 boat which we have run gas in at 45" long. Some sizes were sold to me with two sets of molds and I have made other sets, all remain in my possession since the original sale. Beware of more modified splash hulls out there. FYI, the 40 boat is 37.5 inches long, the 60/80 boat is 42 inches long and the 90 boat is 45 inches long. I have played with some other hulls to come up with a larger gas boat but have not marketed them as Oval Master hulls yet, still tweaking. Hopefully now mostly retired, I can again travel and race on a more regular basis. I have purchased a building here in Bay Saint Louis just for hot rods and model boats.

If you need anything, let me know. I can also make you Hitech Thunderboats, Sport Hydros, Crackerboxes, Crackerboxes with the inset transom, 20 to gas sized tunnel hulls, and several deep vees but I do not know the lineage of them as the guy from Hitech seemed to be a real piece of work and sold multiple sets to multiple people. I do not think the papers allowing me to market and use the Hitech name from him are worth anything and I have not sold one of the boats for the same reason.

Sorry for the long post but any Oval Master molds out there did not come from Don or myself. Chris Herzog inquired about buying the 42 and 45 inch molds from me shortly before he sold Hurricane boats as he and his dad were instrumental in the design of the two larger hulls. Talk soon, Mark

 

[MarkDanielsSr]

Little more info, David the yellow deck boat sure looks nice but is not a Witchcraft from Houston (Baytown) Texas. I will try to get the promised pictures posted tomorrow evening. The Witchcraft called for the small skeg under the motor, leading edge not sharpened, when we were all running sub surface drive. The purpose was to break up the water in front of the prop. I tried 40 and 65 motors without it and it did work. We lost the small mid skeg as surface drive gained favor and the boats from the family of hulls like Muck and Youngblood appeared and got faster. Those hulls also gave birth to the large spin fin on the inside rear as the larger surface drive props gave the mono hulls hell in the turns. We added them to the other hulls, Witchcraft and Wardcraft as they were converted to surface drive also. Once set up as surface drive the small mid ship skeg was not necessary. The yellow decked boat pictured from David sure looks like the Muck/Youngblood style of hull. Scott's Witchcraft hulls were only offered in two sizes, 20 size and the bigger boat at 38 inches long. Monday or Tuesday I will get pictures of both posted here.

 

[the german]

Hey Mark

So i guess i have a original one from Don Wagner.

There is a stamp (A/S) on the transom of my hull and as far i know Carl Cisneros purchased the hull back in the 90' when the Avenger/Spider riggers where popular in Germany.

Alex