Cox Engines Forum
You are not logged in! Please login or register.

Logged in members see NO ADVERTISEMENTS!


Cox .020 cylinder tap 25/64-48 Cox_ba12





Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Cox Engine of The Month
January-2022
Mark Boesen's

Twin Needle Thermal Hopper with a Cage Mount.



PAST WINNERS
CEF Traveling Engine

Dick Russ Models
Win This Engine!
Forum Store
CEF Ear Savers
Gallery


Cox .020 cylinder tap 25/64-48 Empty

Cox .020 cylinder tap 25/64-48

Go down

Cox .020 cylinder tap 25/64-48 Empty Cox .020 cylinder tap 25/64-48

Post  Jason_WI Tue May 05, 2020 5:42 pm

Looking to see where one might find one of these odd ball taps. 25/64-48 or referred as 0.390-48 UNS 3A.

Is the Pee Wee crank shaft diameter equal to 4mm or is it slightly bigger?



Jason_WI
Jason_WI
Top Poster
Top Poster

2020 Supporter

2021 Supporter

2022 Supporter

Posts : 3116
Join date : 2011-10-09
Age : 46
Location : Neenah, WI

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  EXModelEngines Tue May 05, 2020 6:44 pm

@Jason_WI wrote:Looking to see where one might find one of these odd ball taps. 25/64-48 or referred as 0.390-48 UNS 3A.

Is the Pee Wee crank shaft diameter equal to 4mm or is it slightly bigger?




I can have one of my tooling shops quote for you, but will likely cost between $50-$60 and that is if we take a few.

PW crank is larger than 4mm
EXModelEngines
EXModelEngines
Platinum Member
Platinum Member

Official Cox Dealer
Posts : 817
Join date : 2011-06-07
Location : Central CT, USA

http://www.exmodelengines.com

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  Jason_WI Tue May 05, 2020 7:01 pm

Matt,

This project probably won't happen so I wouldn't want to have you have extra taps no one else would buy. I have an inquiry into Newman tools in CT about a tap.

Do you happen to know the exact size of the PW crankshaft?

Seems like Cox pulled random numbers out of a hat for crankshaft sizes. I'm sure some engineering calculations went into it and never thought of standard bearing race sizes available at the time.
Jason_WI
Jason_WI
Top Poster
Top Poster

2020 Supporter

2021 Supporter

2022 Supporter

Posts : 3116
Join date : 2011-10-09
Age : 46
Location : Neenah, WI

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  Dave P. Tue May 05, 2020 10:16 pm

Whatcha workin on Jason? Sounds interesting...
Popcorn
Dave P.
Dave P.
Gold Member
Gold Member

2020 Supporter

Posts : 477
Join date : 2017-07-31
Age : 64
Location : Durham, NC

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  Jason_WI Tue May 05, 2020 11:07 pm

Probably a big waste of time. I have my doubts it will work. Don’t want to mention anything just yet.
Jason_WI
Jason_WI
Top Poster
Top Poster

2020 Supporter

2021 Supporter

2022 Supporter

Posts : 3116
Join date : 2011-10-09
Age : 46
Location : Neenah, WI

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  EXModelEngines Wed May 06, 2020 7:25 am

@Jason_WI wrote:Matt,

This project probably won't happen so I wouldn't want to have you have extra taps no one else would buy. I have an inquiry into Newman tools in CT about a tap.

Do you happen to know the exact size of the PW crankshaft?

Seems like Cox pulled random numbers out of a hat for crankshaft sizes. I'm sure some engineering calculations went into it and never thought of standard bearing race sizes available at the time.

Let me look it up and will let you know if I have it.

Newman is a good outfit - very familiar with those guys.
EXModelEngines
EXModelEngines
Platinum Member
Platinum Member

Official Cox Dealer
Posts : 817
Join date : 2011-06-07
Location : Central CT, USA

http://www.exmodelengines.com

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  1/2A Nut Wed May 06, 2020 10:12 am

If your doing what I think you are it will work that carbon can handle the heat, ceramic bearings
should stay put less heat.  Remember Testers had a run of plastic crankcases back in the day.

Small Cox Logo Thumbs Up
1/2A Nut
1/2A Nut
Top Poster
Top Poster

2021 Supporter

Posts : 3149
Join date : 2013-10-20
Age : 58
Location : Brad in Texas

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  Jason_WI Wed May 06, 2020 2:31 pm

Single tap cost is $230. Sad

I don’t think I will move forward with this idea.
Jason_WI
Jason_WI
Top Poster
Top Poster

2020 Supporter

2021 Supporter

2022 Supporter

Posts : 3116
Join date : 2011-10-09
Age : 46
Location : Neenah, WI

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  1/2A Nut Wed May 06, 2020 7:51 pm

I will donate $115 towards a .020 tap!

Small Cox Logo RC Plane Thumbs Up
1/2A Nut
1/2A Nut
Top Poster
Top Poster

2021 Supporter

Posts : 3149
Join date : 2013-10-20
Age : 58
Location : Brad in Texas

Back to top Go down

Cox .020 cylinder tap 25/64-48 Empty Re: Cox .020 cylinder tap 25/64-48

Post  Sponsored content


Sponsored content


Back to top Go down

Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum