DB01, do I NEED hex screws?

[GTodd 1344]

Hey gang, I just bought a Durga my son is going to build.  Since it’s inception I’ve heard about the cheese screws and hard plastic.  Do I need hex screws? Can I use aw grease to help the screws?

[Misterp180 257]

Following this to see if you get some sound advice! I have one on the way also 😎

[Alexei 547]

if you are going to change from tapping to M3 thread screws on a new kit, i would highly recommend getting the Tamiya M3 machine thread cutting tool. it has made things much easier for me when i installed M3 machine crews on my FF-03 and TT-02S. but has to be used on new plastic parts, wont work good with plastics that have had tapping screws installed.

[GTodd 1344]

2 hours ago, Alexei said:

if you are going to change from tapping to M3 thread screws on a new kit, i would highly recommend getting the Tamiya M3 machine thread cutting tool. it has made things much easier for me when i installed M3 machine crews on my FF-03 and TT-02S. but has to be used on new plastic parts, wont work good with plastics that have had tapping screws installed.

That’s the issue all the screws on the DB01 are M3. I’ll just give it a wirl and see what happens!

[sosidge 624]

Use a JIS screwdriver.

[Jonathon Gillham 4605]

I just built one and used the kit screws, and the Tamiya JIS (I assume since its Tamiya branded) screwdriver and it was generally fine, but some screws going into the harder plastics were a mission. I didn't tap any holes first.

My son simply couldn't have done it, hes only 9 but built the vast majority of a Fire Dragon recently with only guidance rather than me doing everything for him or 'starting it'. In saying that, I don't think he could have done it with hex screws either.

Hex screws would have made life a lot easier on a relatively small amount of the screws. I will probably replace them if it gets worked on a lot, it was bought as a casual runner which spends most of its time on the shelf so it probably won't matter to me. If i was racing it then I would replace them, which isn't something that would bother me on the TA07 as none of those screws are that hard to screw in (they are hex anyway, but just for conparison).

[speedy_w_beans 4272]

The kit JIS screws are fine if you use a good screwdriver (JIS tip or equivalent).  The small suspension blocks are made of very stiff plastic and benefit from running a thread-forming tap through them first.  Otherwise the rest of car can be built just fine with the kit screws.

[jonboy1 2943]

100% buy an M3 tap. They are only a few £ and will save you a lot of grief. As mentioned previously, the plastic in this chassis is very hard, you can get the screws to cut into them, but the chances are you will damage the heads of the screws doing it, trust me, I know! The big disadvantage of not tapping the threads first is that every time you insert or remove the screw you are going to be fighting the plastic, so it will always be a struggle. The reason being that with a tap, you cut out the plastic in a thread form, so it is always going to be a perfect size and fit. When you just go straight in with a screw you are pushing the plastic into the thread form, but not actually removing any material. So it is constantly under pressure against the screw, wanting to go back to it's original shape of a straight hole. So as soon as you remove the screw, the plastic goes ever so slightly back to it's original shape, meaning it will be tight screwing it back in again.

Definitely get a JIS screwdriver (although why anyone who has a Tamiya but doesn't have the blue Tamiya tool set 74085 is beyond me.) There are 2 reasons for this: 1, the obvious one, the driver fits the screw head properly so you are less likely to damage it, and 2, the shaft of the screwdriver is correct. Often overlooked by anyone who has never built an ORV chassis is the fact that sometimes the screws are deep in a hole, so if your screwdriver shaft is ever so slightly too big it will be almost impossible to get to the head properly. This is the same with the DB-01 chassis. Where the drive belt covers and upper halves of the gear cases mount to the chassis some of the screws are sunk down, and it's very easy to find you are grinding away at the edges of the holes rather than the head of the screw. If you pre-thread the holes this becomes a lot more obvious if this is happening as you aren't using as much force to get the screw in.

[alvinlwh 5891]

If you are getting a JIS screwdriver, get the old version as the new version (V2) is more or less a standard Philips and will cam out. 

 

[Gabranth 216]

I'm also building Durga as well, hand-tapping some screw holes and they ended up fine. I said some because there are few that I neglected, but I haven't got any incident so far, on those holes I didn't tap I just tried being careful and taking my time. A tiny bit of grease helps too.

[GTodd 1344]

Thanks guys!

[GTodd 1344]

I ordered a tap and a jis driver set.  I’m impatient and so is my little dude. We just started the build. First (2) steps done with no issues! Diffs drying.  Will see if the tap and jis were needed. Fun build so far!