crank work

[Gary Lauer]

I am rebuilding a older novarossi and want to know if ramping the crank works. If so what do you use to put the ramp in a crank?

 

[Ray Sametz]

https://www.intlwaters.com/threads/putty-ramp-in-crank-of-intake.23876/

 

[steve wood]

spend your time on transfer and exhaust timing,crank timing, and head clearance and head volume.this is where the big gains are. then work on your props

 

[Jim Allen]

The ramps shown in these photos are used in Nelson .45 long stroke pylon racing engines. The machined phenolic base pieces are glued in place with JB weld after roughing the inside surface of the crankshaft. Roughing of the gluing area is done with a dremel tool & a round nose carbide bit. After the phenolic piece is glued in place, a thin coating of JB weld is applied to the top surface of the phenolic piece. A small toaster oven is used to heat the crankshaft first. The heated crankshaft gives the JB weld a faster curing time & causes the JB weld to flow out smoothly. Cotton swabs are used to get the JB weld into the small crankshaft area & on top of the preglued phenolic piece. Some practice will be required to get the proper technique. If done properly, the ramps will remain in place over the life of the crankshaft. Engines with ramped cranks pipe up much more easily & showed a RPM increase of 300 to 400 RPM's on the high end. These engines operate in the 29,000 to 32,000 RPM range.

Jim Allen

 

[dwilfong]

liquid Devcon works killer.
https://www.staples.com/DEVCON-5-Mi...OUFIPPmPX4a3RbMIThS19DI1tu7GtIwAaAtv_EALw_wcBJust set the crank on a block to get the right angle and put some in. It will self level and never come out.
Like Jim stated rough it up some with a dremel bit first.
I use it to fill rod holes and holes from digging to much out in my cases....................LOL
Easy to mix and easy to use it is a no brainier.

 

[Jim Allen]

David,

There is a better epoxy that we are testing made by Hysol. It appears the JB weld has changed their formula slightly. I'll get the full information when I return to work.

JA

 

[shoboat]

Jim,

Is that the Ultrabond HS-1CC
Looks like a great product

 

[dwilfong]

Devcon makes many different Epoxy mixes.
It is not cheep if you buy the lb containers.
Go to there web sight and check it out. Devcon Products
The liquid self leveling is great for this kind of work.
I use the aluminum base stuff in my Mercury V6 2.5 to fill in spots to stuff the case.
Also use the regular to patch holes in the block from rods looking for a way out......LOL

 

[Jim Allen]

Jim,

Is that the Ultrabond HS-1CC
Looks like a great product

No answer yet. We decided to use the machined phenolic piece once we determined what slope the ramp needed in order to be effective.

JA

 

[Jim Allen]

Mark,

HYSOL Locktite # 237095, MSC # 00611517, or Scotch-Weld DP-100 3M, MSC#65861601 work well. One important key is the pre-machined phenolic base piece.

Jim Allen

 

[Gary Lauer]

thank's for the information, time I get to work.

 

[MikeReed]

No answer yet. We decided to use the machined phenolic piece once we determined what slope the ramp needed in order to be effective.

JA

Hello Jim,
I can't determine from the picture but what Phenolic are you using? I don't use a lot of it but assume its the fiberglass based stuff? I've only used the brownish paper based stuff and its not near as fun to machine as I thought it would be.

Mike

 

[Jim Allen]

Hi Mike,

Mike we use only linen based phenolics. Be aware there are many different grades. Select a finer linen based grade if possible. They all work & will absorb the resin if heated slightly because the phenolic is porous,

Jim Allen