HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Feb 28, 2013, 09:10 PM
AMA 1042906
swimmer's Avatar
United States, KS, Derby
Joined Mar 2008
1,156 Posts
Discussion
Battery Hatch Build....

Converting a GP Slowpoke 40 to electric is my goal as I build the kit. To do this I'll have to fab a battery hatch between the two forward formers. Because the most forward former is shorter than the second I don't see quite how to place the balsa onto the bones. Would the outside pieces go on flush with the bottom of the hatch and then a odd shaped piece made to fill the top? Hope I explained it good enough.
swimmer is online now Find More Posts by swimmer
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 28, 2013, 09:48 PM
Hobby King Hater
Kimber's Avatar
USA
Joined Mar 2005
4,593 Posts
We are going to do one later, will be watching.

You have to get creative....

This is a P-51, the fuselage is similar to the SP. Which will
have a much smaller battery.





I can post a pic of the inside of the hatch if needed??
Kimber is offline Find More Posts by Kimber
Last edited by Kimber; Feb 28, 2013 at 11:13 PM.
Reply With Quote
Old Feb 28, 2013, 10:47 PM
AMA 1042906
swimmer's Avatar
United States, KS, Derby
Joined Mar 2008
1,156 Posts
Thanks. I would like to to see inside.

Is that a Tacon motor?

Allan
swimmer is online now Find More Posts by swimmer
Reply With Quote
Old Feb 28, 2013, 10:59 PM
Hobby King Hater
Kimber's Avatar
USA
Joined Mar 2005
4,593 Posts
Quote:
Originally Posted by swimmer View Post
Thanks. I would like to to see inside.

Is that a Tacon motor?

Allan
Yes, 46 size.







The end pieces are 1/8th ply X 2 laminated. The rails are
spruce.

Not to hog your thread, but here is the finished plane.

Kimber is offline Find More Posts by Kimber
Last edited by Kimber; Feb 28, 2013 at 11:15 PM.
Reply With Quote
Old Mar 01, 2013, 10:58 AM
Visitor from Reality
United States, VA, Arlington
Joined Dec 1996
12,788 Posts
HI Swimmer
Having electrocuted the odd slimer kit over the years, here's a few pointers that may help you.

Real Big One. Start early in the build - before you build the fuselage is ideal. Sitting looking at a nearly complete fuselage wondering how to fit a hatch is Not Very Bright. I'l start by eyeballing where I reckon the battery will need to go to nail the CG, then draw the hatch up onto the plan. You will likely have to come up with new formers for the front and rear of the hatch - if you can use an existing one, you got lucky. Once you have that shape, two are needed - one for the fuselage structure, one for the hatch.

Go search around the Sports and glow to electric conversion forums up the top in the E-power sections. Most low wingers are similar when it comes to fitting a battery hatch.

Hatch framework. Mine are pretty much all the same. Hatch bottom is 1/16" balsa, grain across the fuselage, formers are 1/8" balsa or whatever's handy. THere's one at each end, one or two in the middle, with a top stringer of 1/8" x 1/4". Top is 1/16" balsa sheet rolled over the formers. I usually use a ply tab at the front, two magnets at the back end. Hatches aren't structural, so can be lightly made.

Battery. When you figure out a fore and aft location, usually forwards with LiPos to nail the CG, figure out a battery tray low down in the fuselage and just over the wing in a low winger. I'll put in a short tray at my best guess, extend it forwards or back if necessary.

When you have the woodwork pretty well together, put all the expensive little bits in and assemble the model. Drop the battery in and see how your guesstimation of the CG is doing. Again, much better than looking at a near complete model and wondering how to fix that you can't get at the battery and the CG's way too far back. Yes, covering the model will shift the CG aft a little, but just guess that too.

Good luck with the conversion, it's a cute model.

D
Dereck is offline Find More Posts by Dereck
Reply With Quote
Old Mar 01, 2013, 12:28 PM
AMA 1042906
swimmer's Avatar
United States, KS, Derby
Joined Mar 2008
1,156 Posts
Quote:
Originally Posted by Dereck View Post
HI Swimmer
Having electrocuted the odd slimer kit over the years, here's a few pointers that may help you.

Real Big One. Start early in the build - before you build the fuselage is ideal. Sitting looking at a nearly complete fuselage wondering how to fit a hatch is Not Very Bright. I'l start by eyeballing where I reckon the battery will need to go to nail the CG, then draw the hatch up onto the plan. You will likely have to come up with new formers for the front and rear of the hatch - if you can use an existing one, you got lucky. Once you have that shape, two are needed - one for the fuselage structure, one for the hatch.

Go search around the Sports and glow to electric conversion forums up the top in the E-power sections. Most low wingers are similar when it comes to fitting a battery hatch.

Hatch framework. Mine are pretty much all the same. Hatch bottom is 1/16" balsa, grain across the fuselage, formers are 1/8" balsa or whatever's handy. THere's one at each end, one or two in the middle, with a top stringer of 1/8" x 1/4". Top is 1/16" balsa sheet rolled over the formers. I usually use a ply tab at the front, two magnets at the back end. Hatches aren't structural, so can be lightly made.

Battery. When you figure out a fore and aft location, usually forwards with LiPos to nail the CG, figure out a battery tray low down in the fuselage and just over the wing in a low winger. I'll put in a short tray at my best guess, extend it forwards or back if necessary.

When you have the woodwork pretty well together, put all the expensive little bits in and assemble the model. Drop the battery in and see how your guesstimation of the CG is doing. Again, much better than looking at a near complete model and wondering how to fix that you can't get at the battery and the CG's way too far back. Yes, covering the model will shift the CG aft a little, but just guess that too.

Good luck with the conversion, it's a cute model.
D
I'm just building the fuselage and planning battery placement so I guess that makes me bright? Thanks!

I will be able to use a kit former for the front of the hatch and build a new front former out of a thicker balsa. The hatch former will be directly behind the fabricated former and I will connect the hatch to it. I will have to build another aft former so your suggestions will come in handy. The electrified Slowpoke is notoriously tail heavy so the battery will be mounted as far forward as possible and then still may need additional weight to get the CG to the manufacturers suggestion.

Allan
swimmer is online now Find More Posts by swimmer
Reply With Quote
Old Mar 01, 2013, 01:04 PM
Visitor from Reality
United States, VA, Arlington
Joined Dec 1996
12,788 Posts
HI Allan
I got lucky - not long before my first seriously performing electrocution - a Four Star 40 with 20 nicad cells - I saw one done along similar lines but with lots of things to avoid. It became something of a habit. Also tend to mess with structures that aren't my own design - for one example, I took Sig's new Four Star 20 kit and altered it from a bottom to top battery hatch.

Good that you've noticed the 'Poke's tailheaviness. Might want to look at moving the fuselage servos to ahead of the CG, as your battery is going to be ways up front. Rumour once suggested the Slowpoke design was inspired by Henry Ford's 'Flivver' single seater from the 1920s, and that aircraft was very lacking in nose length of any sort.

D
Dereck is offline Find More Posts by Dereck
Reply With Quote
Old Mar 01, 2013, 09:58 PM
AMA 1042906
swimmer's Avatar
United States, KS, Derby
Joined Mar 2008
1,156 Posts
Progress.....

OK, here is where I'm at on the hatch. It will have to attach like Kimbers with two magnets and locator pins. The hatch slips between the two formers.

Allan
swimmer is online now Find More Posts by swimmer
Last edited by swimmer; Mar 01, 2013 at 10:05 PM.
Reply With Quote
Old Mar 01, 2013, 10:20 PM
Hobby King Hater
Kimber's Avatar
USA
Joined Mar 2005
4,593 Posts
Looking good.
Kimber is offline Find More Posts by Kimber
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question How to make my battery hatch rozza2013 Balsa Builders 7 Feb 05, 2013 04:58 AM
Question How to make my battery hatch rozza2013 Beginner Training Area (Aircraft-Electric) 4 Feb 03, 2013 09:01 AM
Discussion Good Ways to Build Access Hatches/Compartments out of fiberglass and Secure Them? quicky Composites Fabrication 1 Jun 09, 2009 09:01 PM
Build Log Adding a Canopy Hatch to Sheath Nosecone Build Log Neil Stainton Electric Sailplanes 13 May 07, 2007 10:45 PM