Pee Wee Mounting Question

I had tried a #2 screw but it seemed to tight, I will give it another try. The 200,000 .020 is in reference to the engine I won by being the one to make the 200,000 post.

here is the table of sizes i've been collecting, looks #2

Mounting screws coarse wood
#2 x 1/2
2mm x 13mm long

.010 prop - 2-56 x 5/8”
.010 backplate screw - 2-56 x 1/4” filister head

.020 prop - 3-48 x 3/4”
.020 backplate screw - 2-56 x 1/4” filister head
.020 glow 25/64-48 tap

.049 prop - 5-40 x 1”
.049 stud - 5-40 x .8”
.049 backplate screw - 2-56 x 1/2” round head
.049 short tank - 2-56 x 3/4” fillister head
.049 long tank - 2-56 x 1” fillister head
.049 glow - 17/32-40 tap

Very helpful! Copied,printed and put up on my workshop wall.

oh my, i should have put naughty words in it, so they stayed up on the wall and made ya laugh more

Any luck with the #2?

yes and no. The yes part is I tried some #2 servo mount screws from RTL but the head hangs up on the seam between the fuel tank and the back plate. Rater than forcing it I ordered some #2 socket head screws that look to have a smaller diameter head. Shold be in early next week.

Phil,
Be careful...you are talking about the plastic horseshoe backplate...right?

I'll dig out my plastic horseshoe backplate tomorrow and check. It may be different than the tank backplate. That horseshoe backplate is custom created by Jason_WI. That whole bundle of goodies is quite a haul!

706Jim: https://www.coxengineforum.com/t15451-200000-posts

These were the screws that shipped with the CEF backplates in 2019. Looks like they doubled in price since I last ordered them.

https://www.amazon.com/gp/product/B00Z3XEHJ4/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

A #2 socket head should fit there as well. The head needs to be small to fit in the recess in the backplate.

I didn't think the 200k engine would have been flown so I didn't include any mounting screws.

[quote=


706Jim: https://www.coxengineforum.com/t15451-200000-posts[/quote]

Thanks. This slipped past me; hadn't seen it

Damn that is expensive Look 12- cheaper > https://www.microfasteners.com/sts0210-2-x-5-8-socket-head-sheet-metal-screws.html and socket head better !

I bought a bunch of #2 and #4 socket head servo mounting screws at Toledo a few years ago. #4 are obviously too large so I tried the #2 screws to how they fit one of my Pee Wee engines.

Turns out that there are three variations of #2 socket head screws. The oldest ones don't have either a washer or built in washer like the latest versions have. These fit fine without marking up the tank.

If you have the second style (Socket head screw with a washer) these will also work if you remove the washer.

The last type with the built in washer (usually sold as servo mounting screws) won't fit without the washer scratching up the tank body.

There are two other fasteners that can be used as well. #2 button head screws will work and look really slick. You just have to remember to thread the holes with a regular screw before installing them as the hex is miniscule and strips easily if you attempt to thread them into plywood.

Finally #2-56 machine screws and nuts also work well, but the extra work to fit the nuts is really not required for such a low powered engine.

So how's that for a long winded answer to a simple question?