On my second week and only about 10 jobs in on using the new Blast to post process our parts and there is an issue we are having with what looks like the padding inside the tumbler rubbing off onto the parts. If you rub a clean glove over the material you can see what I am talking about.
It does not appear to be glass bead as this is the recommended grit and has only been run a few times. It is a “tacky” residue and when on the part almost feels like you rubbed a “tack cloth” onto the part… if any of you are wood workers you’d know what I am talking about.
I am almost certain it is the actual material rubbing off of the tumbler insert.
I am still trying to get on a rhythm with this new Blast workflow and while it does shave a good bit of time off the post processing… I am finding that I have to go back and run each part by hand under the manual position in the cabinet to clean off this residue before or after dying the parts.
If I try to run the parts after dying you can see better how bad it is on every edge that comes into contact with the tumbler padding
Although it looks like they been tumbled “in the ocean on the beach”…and all worn out… all that white residue will blast off when done manually… leaving the parts looking like new again…
To me…there is an issue with whatever the material is made out of for the tumbler padding is coming off onto the parts and wandering if a more fiber like material, like HVAC padding would do better…instead of this rubber like insert being used…
Anyone else experiencing this?
Cabinet is built well and again, it is shaving some time off the post processing but I am now having to come back and hand blast the parts off one by one which is adding a process that I did not have to ever do before using it…
That is odd, I’ve never experienced this issue. It does look similar to the glass bead breakdown problem, but it seems impossible for that to be the case. That definitely should not be occurring after only ~10 jobs. Not to mention it isn’t happening when blasting manually. I didn’t feel any “tack” with my glass residue issue, so I think you’re correct in ruling that out.
If you wanted to further verify that it is the tumbler lining causing the issue, you could try and use a part cage around a test piece or install a liner as you mentioned. Since a new basket liner is $350, I hope you’re provided a replacement or are able to find a cheaper solution.
Cage test would not show anything as this residue is definitely rubbing off of the liner/padding in the tumble and not from the blast media. Any edge that brushes on the liner is getting that residue on it from the liner. I honestly think running “no padding” would give me a better result on a slow tumble over this padding that appears to be breaking down… I use similar fiber padding as filtering for our Cerakote spray booth and that I would think would be better versus a rubber like material…
I’ve been putting heavy use on a Blast unit purchased in May. Running glass media up until last month when the Polisher came out. Never had any issues with the basket liner breaking down or causing residue to appear, so maybe you got a defective liner, or they made a change to the material.
It was great during its initial few uses but definitely no longer “white glove” on the parts. I reached out to Formlabs Support so we will see what they say.
Currently talking this through with Support but in the end the tumbler liner is clinging with fine SLS powder from what it seems. I ran multiple cycles without any parts in hopes to remove or clean the padded liner but that did not do much. The best I was able to do was to use about a dozen latex gloves as rags to wipe the inside of tumbler to try to remove the bulk of it…but it’s endless.
I have not even hit any of my maintenance windows but the filters are clean and I have cleaned them multiple times while running the Blast with no parts while cleaning out the entire hopper and replacing it with new glass bead.
In the end…wiping the tumbler down with the latex gloves at least knocked the issue down a bit but the parts are definitely not “White Glove” out of the tumbler…or maybe they are as this residue is white…but it is definitely not “Black Glove” haha
The Blast is well worth the purchase though as it does cut time down greatly but I will still have to do a quick manual pass of each part to remove this residue.
I was experiencing this for the first 3 months of acquiring the Blast.
I just assumed it was glass media breakdown and lowered my blast pressure to 25PSI, leaving the rinse pressure at 40, this helped to remove any residue on my parts.
My assumption was based on how this residue appears on the door seal.
Your observations that this is only happening with the tumbler are great. I use manual mode mostly due to the size and shape most of my prints.
From I have read in this thread and based on my experience with lowering the blast pressure, I would suggest that the glass media is damaging the lining over time.
Funny you suggest “lowering the blast pressure”… as the Formlabs support rep suggested “upping the blast pressure”…and resorting to yet again just sending new parts…in this case another tumbler liner…that obviously won’t remedy this issue.
Lowering the blast pressure makes more sense to me though as you suggested…as this is obviously super fine SLS n glass bead impregnating the liner at higher psi.
At this point my suggestion to Formlabs would be to sell their equipment through local dealers that can handle the support calls in a more “personal” manner…versus playing round n round with free parts hoping we figure it all out on our own…
As these support calls get more drawn out you get a different rep every week and it’s like starting from scratch explaining the issue to them…
The difference is that I have not contacted support for most of my issues with the Blast.
I am not surprised that Formlabs told you to “up the blast pressure”.
I have often questioned their suggestions.
The other reasons to not use higher pressure is a higher risk of damaging the part and using up the precious air tank capacity.
If you end up trying the lower pressure solution, I’d be curious to hear how it changes your experience. If it improves like it did for me.
You are right in that dealing with Formlabs leads to a drawn out solution.
We got our FUSE 1 from a dealer, the support was not much better, Many responses were slower because the dealer had to ask Formlabs anyway.
Received a new tumbler liner to install and upon removing the old one… I can see why it was pointless trying to wipe off the white residue inside… as it was piled on thick between the liner and tumbler.
This is the inside of the liner with all that white residue packed in between it and the tumbler itself… this is why whipping it was “endless”…it just kept leaking out onto the parts.
That’s just from 2 weeks of mild usage with glass bead… hence why I was unable to pull the parts straight from the tumbler to the dye tank without manually running them each under the nozzle otherwise they would be coated in that stuff.
I had a job come in that would be a good use of the polisher upgrade so I ordered and just installed that with the brand new liner.
Now… my only wish would be to get a second full tumbler and liner… to keep this one clean for polishing and the second for switching to glass for some parts with tight tolerances where I see the polishing media will get jammed into…
With the liner itself costing $350… I am wandering how much Formlabs would want for a full tumbler?
This would be easy to do as the tumbler just lifts right out and can be swapped pretty easily…
But yea… that is the “white residue” that I had going on…
Why not invest in a vibratory tumbler or a professional blast chamber? I doubt you’d be having these issues and the prices are actually cheaper. All you’re doing is paying that “Formlabs Tax” for an inferior yet pretty product.
Because I already have an industrial Blast cabinet that I’d like to dedicate to Garnett and blasting metal parts…and I have a Formlabs Blast…which does a better job at containing, filtering and sifting SLS powder from parts… why would I buy a third cabinet rather than just swap tumbler baskets…
Also, I am actually pretty impressed with the polishing upgrade so far on the Blast…looking great so far.
Vibratory tumbling won’t get internal of the complex parts that make SLS worthwhile over our CNC parts…
